Novel blend compositions containing trivalent doped cerium oxide and silver zinc zeolite for biological pollutant removal

Abstract

The present disclosure relates to novel blend compositions for biological contaminant removal, containing a particulate oxide composition and a silver-zinc zeolite. The particulate oxide composition is a mixed oxide of at least cerium and a trivalent dopant. These blend compositions can be used as antimicrobial / antibacterial / antiviral agents. Accordingly, the present disclosure also relates to the use of these blend compositions for biological contaminant removal. The blend compositions have applications for removing bacteria, viruses, protozoa (e.g., amoeba), fungi (e.g., mold), algae, yeast, and the like. In particular, these blend compositions can be used in methods for contact-treating fluids, including liquids or air, and solid surfaces.

Description

[Technical Field]

[0001] Related Applications This application is being filed as a PCT international application on January 11, 2024, and claims priority to and benefit of U.S. Provisional Application No. 63 / 479,518, filed January 11, 2023, the disclosure of which is incorporated herein by reference in its entirety.

[0002] The present disclosure relates to novel blend compositions for biological contaminant removal containing trivalent-doped cerium oxide (CeO) particulate compositions and silver-zinc zeolite. These blend compositions can be used as antimicrobial / antibacterial / antiviral agents. Accordingly, the present disclosure also relates to the use of these blend compositions for biological contaminant removal. The blend compositions have applications for removing bacteria, viruses, protozoa (e.g., amoeba), fungi (e.g., mold), algae, yeast, and the like. In particular, these compositions can be used in methods for contact-treating fluids, including liquids or air, and solid surfaces. [Background technology]

[0003] Introduction Various techniques have been used to remove biological contaminants from air and aqueous systems. Examples of other techniques for removing biological contaminants include adsorption onto high-surface-area materials such as alumina, filters with pore sizes smaller than the biological contaminants, and the use of highly oxidizing materials such as chlorine and bromine. Certain metals have also found use because they exhibit the oligodynamic effect, which is the metal's biocidal effect. Metals known to exhibit the oligodynamic effect include Al, Sb, As, Ba, Si, B, Cu, Au, Pb, Hg, Ni, Ag, Th, Sn, and Zn. Incorporating these into technologies for air or aqueous system treatment remains a challenge due to significant concerns about toxicity to human and animal life and costs. In particular, silver is widely used in medical and consumer products due to its antimicrobial activity, which is broad-spectrum. Despite many beneficial innovations in the use of silver as an antimicrobial agent, its use can have negative environmental impacts and potentially toxic effects on keratinocytes and fibroblasts. At the very least, silver is known to cause skin irritation, and efforts have been made to minimize its use.

[0004] There remains a need for effective and inexpensive antimicrobial materials for removing bacteria, viruses and other microbial contaminants from fluids, including air, water, and other aqueous systems. Summary of the Invention

[0005] The present disclosure generally relates to novel blend compositions containing a particulate oxide composition and a silver-zinc zeolite, and the use of these blend compositions for removing biological contaminants, wherein the particulate oxide composition in the blend composition is a trivalent-doped cerium oxide, i.e., a mixed oxide of at least cerium and a trivalent dopant.

[0006] Disclosed herein is a blend composition for biological contaminant removal. The blend composition comprises less than about 50 wt. % to about 1 wt. % silver-zinc zeolite and greater than about 50 wt. % to about 99 wt. % particulate oxide composition. The particulate oxide composition in the blend composition comprises cerium oxide; a trivalent dopant selected from the group consisting of yttrium (Y), lanthanum (La), neodymium (Nd), praseodymium (Pr), and mixtures thereof; and optionally, an additional metal oxide selected from the group consisting of aluminum (Al), titanium (Ti), zirconium (Zr), hafnium (Hf), and mixtures thereof, wherein the cerium oxide is present in an amount greater than the trivalent dopant, and the average ratio of the trivalent dopant to Ce from about 0 nm to about 3.5 nm from the surface of the particulate oxide composition is greater than the ratio of the trivalent dopant to Ce from about 15 nm from the surface of the particulate oxide composition.

[0007] In certain embodiments, the average ratio of trivalent dopant to Ce from about 0 nm to about 3.5 nm from the surface of the particulate composition is about 10% to about 250% greater than the ratio of trivalent dopant to Ce from about 15 nm from the surface of the particulate oxide composition. In other embodiments, the average ratio of trivalent dopant to Ce from about 0 nm to about 3.5 nm from the surface of the particulate oxide composition is about 15% to about 250% greater than the ratio of trivalent dopant to Ce from about 15 nm from the surface of the particulate oxide composition.

[0008] In certain embodiments of the particulate oxide composition, the particulate oxide comprises cerium oxide in an amount of about 99.9 wt.% to about 20 wt.% based on the total weight of the particulate oxide composition; a trivalent dopant in an amount of about 0.1 wt.% to about 50 wt.% based on the total weight of the particulate oxide composition; and an additional metal oxide in an amount of about 70 wt.% to about 0 wt.% based on the total weight of the particulate oxide composition. Specifically, about 0 wt.% additional metal oxide is present.

[0009] The blended composition has biological contaminant removal properties and thus finds application for removing bacteria or viruses from fluids, including air and water, and / or surfaces. Biological contaminants to be removed include bacteria, viruses, protozoa (e.g., amoebas), fungi (e.g., molds or fungi), and the like. The blended composition can reduce the amount of silver-zinc zeolite while retaining this activity, and the blended composition exhibits better activity than either the silver-zinc zeolite or the particulate oxide composition alone. Thus, the blended composition exhibits unexpected synergy for removing / reducing biological contaminants.

[0010] Also disclosed herein are support compositions, including support materials and blend compositions, that have biological decontamination properties and thus find use in removing bacteria or viruses from fluids, including air and water, and / or surfaces.

[0011] The support compositions disclosed herein for removing biological contaminants include a support material comprising an organic polymer, cotton, glass fiber, or a mixture thereof, and a blend composition described herein, in which the blend composition for removing biological contaminants is deposited on or within the support material.

[0012] In certain embodiments, the support composition comprises from about 0.5 to about 80 weight percent of the blend composition, based on the total weight of the support composition.

[0013] The support composition, including the support material and blend composition, can be in a rigid or elastic form, and the support composition can be made into an article for removing biological contaminants, such as a filter, a fixed bed filter system, a plastic or glass bottle or container, a plastic or glass touch surface, etc.

[0014] In one embodiment, a plastic article is disclosed. The plastic article comprises (i) an organic polymer selected from the group consisting of polyethylene, polyvinyl chloride, nylon, polypropylene, polyester, polyurethane, polyamide, polyolefin, polycarbonate, copolymers thereof, and mixtures thereof, and (ii) a support composition for removing biological contaminants, the support composition comprising the blend composition described herein, wherein the blend composition is deposited on or within the organic polymer. The plastic article comprises about 50 to about 100 weight percent of the support composition for removing biological contaminants, based on the total weight of the plastic article. The plastic article may be a filter, a fixed-bed filter system, a plastic bottle or container, a plastic touch surface, a plastic doorknob or handle cover, a plastic elevator button cover, or the like.

[0015] The blend composition itself, the support composition, and the article can be used in methods for removing biological contaminants, including bacteria, viruses, protozoa (e.g., amoebas), fungi (e.g., molds or fungi), and the like.

[0016] In one embodiment, a method for removing biological contaminants includes (i) providing a blend composition described herein; (ii) contacting the blend composition with a biological contaminant selected from the group consisting of bacteria, viruses, fungi, protozoa (e.g., amoebas), and mixtures thereof; and (iii) removing at least about 90% of the biological contaminant by contact with the blend composition. In some embodiments, the blend composition is contained within a filter material or plastic.

[0017] In certain embodiments, the method treats an aqueous stream and the biological contaminants are in the aqueous stream. In other embodiments, the method treats a gaseous stream and the biological contaminants are in the gaseous stream. In still other embodiments, the contacting is by touching the solid to the composition, thus treating a solid surface by touching. In some of these embodiments, the contacting is by touching the solid to an article comprising the particulate oxide composition.

[0018] In certain embodiments treating fluids (e.g., gaseous or aqueous streams), the method may further include setting a target concentration of a biological contaminant. In these embodiments, the biological contaminant may be identified and a target concentration of the biological contaminant may be set. The method may further include monitoring the treated stream for the biological contaminant. The monitoring may be by sampling or may be continuous.

[0019] In certain embodiments, these methods are for removing biological contaminants from a fluid, and the methods are for treating the fluid. In these embodiments, the fluid may be a gaseous or aqueous stream. The methods include (i) providing a blend composition as described herein; (ii) contacting the blend composition with a fluid (e.g., a gaseous or aqueous stream) containing a biological contaminant selected from the group consisting of bacteria, viruses, fungi (e.g., molds), protozoa (e.g., amoebas), and mixtures thereof; and (iii) removing the biological contaminant from the fluid (e.g., a gaseous or aqueous stream) by contact with the blend composition. The biological contaminant may be removed in an amount of 90% or greater. If the fluid is a liquid, the blend composition may be used by itself, or the method may further include filtering the fluid / liquid.

[0020] In certain embodiments, these methods are for removing biological contaminants from a fluid using a support composition. In these embodiments, the fluid may be a gaseous or aqueous stream. The method includes (i) providing (a) a support material comprising an organic polymer, cotton, glass fiber, or a mixture thereof, and (b) a support composition comprising a blend composition described herein; (ii) contacting a fluid containing biological contaminants selected from the group consisting of bacteria, viruses, fungi (e.g., molds), protozoa (e.g., amoebas), and mixtures thereof, with the support composition; and (iii) removing the biological contaminants from the fluid by contact with the support composition. The biological contaminants may be removed in an amount of 90% or greater.

[0021] These methods of treating fluids or gaseous or aqueous streams using the blend composition itself or the support composition may further include the step of setting a target concentration of a biological contaminant. In these methods, the biological contaminant of interest is identified and then a target concentration of the biological contaminant is set. The method may further include the step of monitoring the biological contaminant in the treated stream. Monitoring may be by sampling or may be continuous.

[0022] In methods for treating aqueous streams, the blended composition may be used by itself by slurrying it with the aqueous stream. These methods involving slurrying may further include a filtering step.

[0023] In certain embodiments, a method includes the steps of: (i) providing (a) a support material comprising an organic polymer, cotton, glass fiber, or a mixture thereof, and (b) a support composition comprising a blend composition described herein; (ii) establishing a target concentration of a biological contaminant; (iii) contacting a gaseous or aqueous stream containing the biological contaminant with the support composition, and removing the biological contaminant by contact with the support composition to provide a treated stream; and (iv) monitoring the treated stream for the biological contaminant, wherein the biological contaminant is selected from the group consisting of bacteria, viruses, fungi (e.g., molds), protozoa (e.g., amoebas), and mixtures thereof. The target concentration can be set at a certain amount of contaminant (e.g., viruses, bacteria, protozoa / amoebas, or fungi) or can be set at a detection limit. Monitoring can be performed by sampling or can be continuous. [Brief explanation of the drawings]

[0024] [Figure 1] 1 is an SEM image of the composition of Example 1 with a scale bar of 200 nm.

[0025] [Figure 2] 1 is an SEM image of the composition of Example 1 with a scale bar of 2 μm.

[0026] [Figure 3] 1 is a TEM image of the composition of Example 1 with a scale bar of 10 nm. The light field image is on the left and the dark field image is on the right.

[0027] [Figure 4] 1 is a TEM image of the composition of Example 1 with a scale bar of 20 nm. The light field image is on the left and the dark field image is on the right.

[0028] [Figure 5A] Temperature programmed desorption of CO2 for the composition of Example 1.

[0029] [Figure 5B] Temperature programmed desorption of CO2 for the composition of Example 2.

[0030] [Figure 5C] Temperature programmed desorption of CO2 for the composition of Example 3.

[0031] [Figure 6] Temperature programmed desorption of H2 for the compositions of Examples 1, 2 and 3.

[0032] [Figure 7] 1 is a graph of zeta potential versus pH for the compositions of Examples 1, 2, and 3.

[0033] [Figure 8] 1 is a graph showing the ratio of LaO+ / CeO+ versus depth for the composition of Example 1 and the composition of Example 2.

[0034] [Figure 9] 1 is a graph showing the ratio of PrO+ / CeO+ versus depth for the compositions of Examples 4 and 5.

[0035] [Figure 10] 1 is an SEM image of the composition of Example 2 with a scale bar of 200 nm.

[0036] [Figure 11] 1 is an SEM image of the composition of Example 2 with a scale bar of 20 nm.

[0037] [Figure 12A] 12B is a light-field TEM image of the composition of Example 2 with a scale bar of 200 nm. The box indicates the zoomed area of ​​FIG. 12B.

[0038] [Figure 12B] 12C is a light-field TEM image of the composition of Example 2 with a scale bar of 20 nm. The box indicates the zoomed area of ​​FIG. 12C.

[0039] [Figure 12C] 1 is a light field TEM image of the composition of Example 2 with a scale bar of 5 nm.

[0040] [Figure 12D] 1 is a dark field TEM image of the composition of Example 2 with a scale bar of 5 nm.

[0041] [Figure 13] 1 is a graph showing the log reduction of MRSA for series Example 1, Examples 7A-D (blends of Examples 1 and 6), and Example 6 (silver zinc zeolite), compared to series Example 3 (CeO), Examples 8B-C (blends of Examples 3 and 6), and Example 6 (silver zinc zeolite). DETAILED DESCRIPTION OF THE INVENTION

[0042] The present disclosure generally relates to blend compositions containing silver-zinc zeolite and particulate oxide compositions containing trivalent-doped CeO. The disclosure also relates to the use of these blend compositions for removing biological contaminants, including bacteria, viruses, and other microbial contaminants, by contact. Thus, these blend compositions are capable of removing biological contaminants from air and aqueous liquid streams, and in particular, are capable of removing bacteria and viruses from air and water, regardless of whether the microorganisms are present in high or very low concentrations. These blend compositions perform better than silver-zinc zeolite alone, allowing for reduced use of silver-zinc zeolite while maintaining effectiveness in removing biological contaminants. These blend compositions also perform better than particulate oxide compositions alone.

[0043] Before the compositions, articles, and methods are disclosed and described in detail, it is to be understood that the disclosure is not limited to the specific structures, process steps, or materials disclosed herein but extends to equivalents thereof as recognized by those skilled in the art. It is also to be understood that the terminology used herein is used only for the purpose of describing particular embodiments and is not intended to be limiting. It should be noted that, as used herein, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, a reference to a "trivalent dopant" should not be construed as limiting a quantity or source, a reference to a "step" may include multiple steps, a reference to the "product" or "product" of a reaction or process should not be construed as all of the products of the reaction / process, and a reference to "processing" may include a reference to one or more of such process steps. Thus, a processing step may include multiple or repeated processing of similar materials / streams to produce a specified process product.

[0044] The singular forms of biological contaminants also include plural referents. For example, "amoeba" and "virus" include references to "amoebae" and "viruses," respectively.

[0045] Numerical values ​​marked with "about" or "approximately" include typical experimental variance. As used herein, the terms "about" and "approximately" are used interchangeably and refer to within a statistically significant range of values, such as a stated weight percentage, surface area, concentration range, time frame, distance, molecular weight, temperature, or pH. Such ranges may be within an order of magnitude, typically within 10%, and even more typically within 5%, of the stated value or range. Sometimes, such ranges may be within the experimental error typical of the standard method used to measure and / or determine a given value or range. The allowable variation encompassed by the term "about" depends on the particular system under study and can be readily understood by one of ordinary skill in the art. Whenever a range is recited within this application, at least every integer within that range is contemplated as an embodiment of the invention.

[0046] The disclosed blend compositions have activity in removing biological contaminants. These blend compositions contain a trivalent-doped CeO2 particulate composition and a silver-zinc zeolite. The trivalent-doped CeO2 particulate composition is also referred to as a particulate oxide composition, and these terms are used interchangeably herein. The particulate oxide composition is comprised of a mixed oxide of Ce and a trivalent dopant.

[0047] The blend compositions disclosed herein can be used as slurries or in support compositions and / or articles intended to remove biological contaminants, including bacteria, viruses, fungi, protozoa (e.g., amoeba), yeast, and mixtures thereof.

[0048] The blend composition disclosed herein is for biological contaminant removal and includes (a) less than about 50 wt. % to about 1 wt. % silver-zinc zeolite, and (b) greater than about 50 wt. % to about 99 wt. % particulate oxide composition. The particulate oxide composition includes cerium oxide; a trivalent dopant (as oxide) selected from the group consisting of yttrium (Y), lanthanum (La), neodymium (Nd), praseodymium (Pr), and mixtures thereof; and optionally an additional metal oxide selected from the group consisting of aluminum (Al), titanium (Ti), zirconium (Zr), hafnium (Hf), and mixtures thereof. In the particulate oxide, the cerium oxide is present in an amount greater than the trivalent dopant, and the average ratio of trivalent dopant to Ce from about 0 nm to about 3.5 nm from the surface of the particulate oxide composition is greater than the average ratio of trivalent dopant to Ce from about 15 nm from the surface of the particulate oxide composition.

[0049] In an embodiment of the particulate oxide composition, it comprises cerium oxide in an amount of about 99.9 wt. % to about 20 wt. % based on the total weight of the particulate oxide composition; a trivalent dopant in an amount of about 0.1 wt. % to about 50 wt. % based on the total weight of the particulate oxide composition; and an additional metal oxide in an amount of about 70 wt. % to about 0 wt. % based on the total weight of the particulate oxide composition.

[0050] The blend compositions disclosed herein comprise from about 50 wt% to about 1 wt% of the silver-zinc zeolite and from about 50 wt% to about 99 wt% of the particulate oxide composition. In certain embodiments, the blend compositions comprise from about 35 wt% to about 5 wt% of the silver-zinc zeolite and from about 65 wt% to about 95 wt% of the particulate oxide composition. In certain embodiments, the blend compositions comprise from about 25 wt% to about 10 wt% of the silver-zinc zeolite and from about 75 wt% to about 90 wt% of the particulate oxide composition.

[0051] In the blend composition, silver-zinc zeolite (Ze-Ag-Zn: CAS No. 130328-20-0) is a Linde type A (LTA) zeolite framework surface-modified with silver and zinc ions, which has applications such as antibacterial coatings. LTA zeolite is a crystalline aluminosilicate with a well-defined three-dimensional framework that is surface-modified with both silver and zinc ions. Ag + The content may be about 0.4% by weight to about 6% by weight, and Zn 2+ The content can be about 1% to about 16% by weight.

[0052] In the blend compositions, the particulate oxide compositions are primarily composed of mixed oxides of Ce and the trivalent dopant, and these particulate oxide compositions are also referred to herein as trivalent-doped CeO compositions or trivalent-doped CeO particulate compositions.

[0053] Thus, the trivalent-doped CeO particulate composition is a mixed oxide of Ce and a trivalent dopant, wherein the trivalent dopant is selected from the group consisting of yttrium (Y), lanthanum (La), neodymium (Nd), praseodymium (Pr), and mixtures thereof.

[0054] In certain embodiments, the particulate oxide composition also contains an amount of an additional metal oxide selected from the group consisting of aluminum (Al), titanium (Ti), zirconium (Zr), hafnium (Hf), and mixtures thereof.

[0055] The blend compositions disclosed herein perform better than silver-zinc zeolite alone, allowing for reduced use of silver-zinc zeolite while maintaining effectiveness in biological contaminant removal. The blend compositions disclosed herein also perform better than the particulate oxide composition alone.

[0056] In the blend composition, the trivalent doped CeO composition or particulate oxide composition comprises cerium oxide, one or more trivalent dopants (as oxides), and optionally one or more additional metal oxides. Thus, the particulate oxide composition comprises a trivalent dopant (as oxide) selected from the group consisting of cerium oxide, yttrium (Y), lanthanum (La), neodymium (Nd), praseodymium (Pr), and mixtures thereof, optionally one or more additional metal oxides other than cerium oxide and the trivalent dopant, and / or trace amounts of impurities.

[0057] The additional metal oxide in the particulate oxide composition may be selected from the group consisting of aluminum, titanium, zirconium, hafnium, and mixtures thereof. In certain embodiments, the particulate oxide composition contains about 0 additional metal oxides. In other embodiments, the particulate oxide composition contains an additional metal oxide.

[0058] The particulate oxide composition exhibits activity in removing / reducing biological contaminants and is used in a blended composition that also contains silver-zinc zeolite. When the two components are used together, the blended composition can reduce the amount of silver-zinc zeolite while maintaining activity, and the blended composition tends to exhibit better activity than either the silver-zinc zeolite or the particulate oxide composition alone. Thus, the blended composition exhibits unexpected synergy for removing / reducing biological contaminants.

[0059] The cerium in the cerium oxide in the particulate oxide composition is Ce(IV). The trivalent rare earth dopant may be selected from the group consisting of yttrium (Y), lanthanum (La), neodymium (Nd), praseodymium (Pr), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), cerium (Ce), and mixtures thereof. In certain embodiments, the trivalent dopant is yttrium (Y), lanthanum (La), neodymium (Nd), praseodymium (Pr), and mixtures thereof, and in certain embodiments, the trivalent dopant is Nd, La, or a mixture thereof. In other embodiments, the trivalent dopant is La. In further embodiments, the trivalent dopant is Pr. As described, the trivalent dopant is present in the particulate composition as an oxide such that the particulate oxide composition comprises a mixed oxide of at least cerium and the trivalent dopant.

[0060] The trivalent dopant is present in a minor amount compared to the cerium oxide, and therefore the particulate oxide composition contains more cerium oxide (also present as the oxide) than the trivalent dopant.

[0061] The particulate oxide composition may also optionally contain additional metal oxides other than cerium oxide and trivalent dopants, which may be selected from the group consisting of aluminum (Al), titanium (Ti), zirconium (Zr), hafnium (Hf), and mixtures thereof.

[0062] Thus, the particulate oxide composition is a mixed oxide composition (i.e., a mixture of oxides of at least cerium and a trivalent dopant). The composition is also identified herein as a trivalent-doped cerium oxide, and when so identified, it is a mixed cerium trivalent dopant oxide, although this description does not exclude additional metal oxides, unless the composition is identified as containing about 0 additional metal oxides other than cerium and the trivalent dopant.

[0063] In certain embodiments of the particulate oxide composition, the trivalent dopant is La and the particulate oxide composition contains about 0 additional metal oxides. In these embodiments, the particulate oxide composition is a mixed cerium-lanthanum oxide (or La-doped cerium oxide).

[0064] The particulate oxide composition includes the trivalent dopant (as oxide) in an amount of from about 0.1 wt. % to about 50 wt. % based on the total weight of the particulate oxide composition. As noted above, the trivalent dopant is present in a minor amount relative to the cerium oxide. In certain embodiments, the particulate oxide composition contains the trivalent dopant in an amount of from about 0.5 wt. % to about 40 wt. %, or from about 1 wt. % to about 40 wt. %, based on the total weight of the particulate oxide composition. In certain embodiments, the particulate oxide composition contains the trivalent dopant in an amount of from about 2 wt. % to about 35 wt. %, or from about 2 wt. % to about 30 wt. %, based on the total weight of the particulate oxide composition. In further embodiments, the particulate oxide composition contains the trivalent dopant in an amount of from about 2 wt. % to about 25 wt. %, or from about 5 wt. % to about 20 wt. % based on the total weight of the particulate oxide composition. In certain of these embodiments, the particulate oxide composition contains the trivalent dopant in an amount of about 15 wt. % based on the total weight of the particulate oxide composition. The trivalent dopant is present in the particulate composition as its oxide, and these weight percentages are based on the trivalent dopant as its oxide. In certain of the above embodiments, the trivalent dopant is lanthanum, and the particulate oxide composition is lanthanum-doped cerium oxide (i.e., a mixed oxide of cerium and lanthanum).

[0065] In embodiments where the particulate oxide composition contains cerium oxide, one or more trivalent dopants, and approximately zero additional metal oxides, the amount of cerium oxide corresponds to and varies with the amount of trivalent dopant such that the total amount of trivalent dopant and cerium oxide (as oxide) is approximately 100% of the particulate composition. In certain of these embodiments containing approximately zero additional metal oxides, the trivalent dopant is lanthanum, and the particulate oxide composition is lanthanum-doped cerium oxide.

[0066] In the particulate oxide composition, cerium oxide is present in an amount greater than the trivalent dopant. The particulate oxide compositions disclosed herein generally include cerium oxide in an amount of from about 99.9 wt. % to about 20 wt. % based on the total weight of the particulate oxide composition. In certain embodiments, the particulate oxide composition contains cerium oxide in an amount of from about 99.9 wt. % to about 50 wt. In certain embodiments, the particulate oxide composition contains cerium oxide in an amount of from about 99.5 wt. % to about 25 wt. % or from about 99 wt. % to about 30 wt. In certain embodiments, the particulate oxide composition contains cerium oxide in an amount of from about 98 wt. % to about 65 wt. % or from about 98 wt. % to about 70 wt. % based on the total weight of the particulate oxide composition. In further embodiments, the particulate oxide composition contains cerium oxide in an amount of about 98% to about 75% by weight, or about 95% to about 80% by weight, based on the total weight of the particulate oxide composition. In certain of these embodiments, the particulate oxide composition contains cerium oxide in an amount of about 85% by weight, based on the total weight of the particulate oxide composition. The amount of cerium oxide varies with and corresponds to the amount of trivalent dopant and any additional metal oxide, such that the total amount is about 100% of the particulate composition.

[0067] In certain embodiments, the particulate oxide composition contains about 0 wt. % additional metal oxide. In these embodiments, the particulate oxide composition contains cerium oxide in an amount that provides about 100% of the particulate composition based on the weight percent of the trivalent dopant. For example, in embodiments containing about 0.1 wt. % to about 50 wt. % trivalent dopant based on the total weight of the particulate oxide composition, the composition contains cerium oxide in an amount of about 99.9 wt. % to about 50 wt. In embodiments containing about 1 wt. % to about 40 wt. % trivalent dopant based on the total weight of the particulate oxide composition, the composition contains cerium oxide in an amount of about 99 wt. % to about 60 wt. In embodiments containing about 2 wt. % to about 30 wt. % trivalent dopant based on the total weight of the particulate oxide composition, the composition contains cerium oxide in an amount of about 98 wt. % to about 70 wt. %.

[0068] As disclosed herein, the particulate oxide compositions may optionally contain additional metal oxides other than cerium oxide and trivalent dopants. These additional metal oxides may be selected from the group consisting of aluminum (Al), titanium (Ti), zirconium (Zr), hafnium (Hf), and mixtures thereof. The particulate oxide compositions disclosed herein generally include the additional metal oxide in an amount of from about 70 wt. % to about 0 wt. %, based on the total weight of the particulate oxide composition.

[0069] In certain embodiments, the particulate oxide comprises cerium oxide in an amount of about 99.9 wt. % to about 20 wt. % based on the total weight of the particulate oxide composition; a trivalent dopant in an amount of about 0.1 wt. % to about 50 wt. % based on the total weight of the particulate oxide composition; and an additional metal oxide in an amount of about 70 wt. % to about 0 wt. % based on the total weight of the particulate oxide composition. In the particulate oxide composition, the cerium oxide is present in an amount greater than the trivalent dopant.

[0070] When additional metal oxides are present, the particulate oxide composition generally contains the additional metal oxides in an amount of about 70 wt. % to about 0.1 wt. %, based on the total weight of the particulate oxide composition. In certain embodiments, the particulate oxide composition contains the additional metal oxides in an amount of about 50 wt. % to about 0.1 wt. %, or about 30 wt. % to about 0.1 wt. %, based on the total weight of the particulate oxide composition. In certain embodiments, the particulate oxide composition contains these additional metal oxides in an amount of about 10 wt. % to about 0.1 wt. %, based on the total weight of the particulate oxide composition. In other embodiments, the particulate oxide composition contains about 0 wt. % additional metal oxide. The amount of additional metal oxide varies with and corresponds to the amount of trivalent dopant and cerium oxide, such that the total amount is about 100% of the particulate composition.

[0071] In one embodiment, the particulate oxide composition comprises a trivalent dopant in an amount of about 2% to about 25% by weight, based on the total weight of the particulate oxide; cerium oxide in an amount of about 20% to about 30% by weight; and an additional metal oxide in an amount of about 45% to about 78% by weight. In the particulate oxide composition, the cerium oxide is present in an amount greater than the trivalent dopant, and the amounts of the components are varied so that the total amount is about 100% of the particulate composition.

[0072] In an alternative embodiment, the particulate oxide composition comprises a trivalent dopant in an amount of about 2% to about 25% by weight, based on the total weight of the particulate oxide; cerium oxide in an amount of about 45% to about 78% by weight; and an additional metal oxide in an amount of about 20% to about 30% by weight. In the particulate oxide composition, the cerium oxide is present in an amount greater than the trivalent dopant, and the amounts of the components are varied so that the total amounts are about 100% of the particulate composition.

[0073] The particulate oxide composition may optionally further contain trace amounts of impurities. These impurities are typically present in amounts of about 1 wt. % or less (up to about 0, or up to undetectable amounts) based on the total weight of the particulate oxide composition. These impurities include residual solvents, salts, other metals, and the like. These other metals include those commonly found in water, such as magnesium, iron, calcium, silicon, sodium, and the like. Amounts of these impurities (from about 1 wt. % to about 0, or up to undetectable amounts) may be present in any of the above and below embodiments of the particulate oxide composition. If present and detectable, any impurity is generally present in an amount of about 100 ppm or less.

[0074] The particulate oxide compositions disclosed herein have a unique depth profile for the distribution of cerium oxide and trivalent dopant. This unique depth profile means that the ratio of trivalent dopant to Ce is higher near the surface of the particulate oxide composition compared to deeper within the particulate oxide composition. Without wishing to be bound by any theory, the unique depth profile of the particulate oxide composition provides unique structural (i.e., physical) and electrochemical properties that, when used in the blend compositions disclosed herein, provide improved activity for removing biological contaminants.

[0075] With respect to depth profiles, those skilled in the art recognize that these particulate oxide compositions have a surface, which is referred to as approximately 0 nm. Those skilled in the art understand how to measure Ce and trivalent dopants from this surface (i.e., 0 nm) to depths (measured in nm) within the particulate oxide composition, and from this measurement can calculate the ratio of trivalent dopant to Ce at different depths and the average ratio of trivalent dopant to Ce.

[0076] The specific depth profile of the particulate oxide composition is characterized such that the average ratio of trivalent dopant to Ce from about 0 nm (i.e., the surface) to about 3.5 nm from the surface of the particulate oxide composition is greater than the ratio of trivalent dopant to Ce from about 15 nm from the surface of the particulate oxide composition. Measurements of Ce and trivalent dopant are taken at specific intervals from 0 nm (i.e., the surface) to about 3.5 nm and then averaged. Measurements of Ce and trivalent dopant are also taken from about 15 nm from the surface of the particulate composition. Figure 8 shows the LaO versus depth profile. + / CeO + 1 is a graph of the ratio of the specific depth profile for one example of a particulate oxide composition used in a blend composition.

[0077] The depth profile of the distribution of cerium oxide and trivalent dopants is measured by time-of-flight (ToF) secondary ion mass spectrometry (SIMS) depth profilometry, as described in Noel, C. et al., ToF-SIMS Depth Profiling of Organic Delta Layers with Low-Energy Cesium Ions: Depth Resolution Assessment, Journal of the American Society for Mass Spectrometry, Vol. 30 (2019) pp. 1537-1544 (the entire contents of which are incorporated by reference). As will be understood by those skilled in the art, a square cross-section of a particle of sample material is selected and analyzed by ToF-SIMS, analyzing at a depth of 0 nm (i.e., the surface). ToF-SIMS works by bombarding a target material with an ion beam, which causes sputtering of the material. Sputtering is the phenomenon of tiny particles being ejected from the surface of a solid material. The ejected particles are then mass analyzed in a mass spectrometer. The ion source for ToF-SIMS analysis in this disclosure is a cesium ion source operating at 2 keV with a target current of 130 nA, with a sputtering size of 500 μm 2 and the analysis area is 200 μm 2The sputtering time was 60 seconds, followed by two frame analysis. The selected square cross section was then etched with an ion beam to remove surface atoms. In this disclosure, the primary ion beam was a bismuth liquid metal ion gun operating at 30 keV with a pulsed target current of approximately 0.6 pA, and the sputtering size was 250 μm. 2 and the analysis area is 100 μm 2 The etching time was 2 frames, followed by 50 frames of sputtering, and 20,000 seconds of sputtering time. The etching time correlates with the etching depth, allowing for depth control. In this disclosure, the sputtering depth was calibrated to 1 nm / s. The exposed surface was then reanalyzed by ToF-SIMS to obtain an analysis at the new depth. The particulate composition can be analyzed at any nm increment, such as about 0.2 nm, about 0.5 nm, about 1 nm, etc. This process is repeated until the desired depth is obtained. The observed mass spectrometry data is then correlated with the depth at which it was collected. In this disclosure, it is important to determine the ratio of trivalent dopant to Ce, and therefore this is the data reported.

[0078] In one embodiment, the particulate oxide composition of the blend composition comprises cerium oxide; a trivalent dopant (as oxide) selected from the group consisting of yttrium (Y), lanthanum (La), neodymium (Nd), praseodymium (Pr), and mixtures thereof; and optionally an additional metal oxide selected from the group consisting of aluminum (Al), titanium (Ti), zirconium (Zr), hafnium (Hf), and mixtures thereof, wherein the cerium oxide is present in an amount greater than the trivalent dopant, and the average ratio of trivalent dopant to Ce from about 0 nm to about 3.5 nm from the surface of the particulate oxide composition is greater than the ratio of trivalent dopant to Ce from about 15 nm from the surface of the particulate oxide composition. In one embodiment of this particulate oxide composition, the composition comprises from about 0.1 wt% to about 50 wt% of the trivalent dopant. In a particular embodiment, the composition further comprises from about 99.9 wt% to about 50 wt% of cerium oxide, based on the total weight of the particulate oxide composition.

[0079] Another embodiment disclosed herein is a particulate oxide composition comprising cerium oxide and a trivalent dopant selected from the group consisting of yttrium (Y), lanthanum (La), neodymium (Nd), praseodymium (Pr), and mixtures thereof, and optionally an additional metal oxide selected from the group consisting of aluminum (Al), titanium (Ti), zirconium (Zr), hafnium (Hf), and mixtures thereof, wherein the cerium oxide is present in an amount greater than the trivalent dopant, and the average ratio of trivalent dopant to Ce from about 0 nm to about 3.5 nm from the surface of the particulate oxide composition is greater than the ratio of trivalent dopant to Ce from about 15 nm from the surface of the particulate oxide composition, and the composition comprises from about 2 wt% to about 30 wt% of the trivalent dopant. In one embodiment of this particulate oxide composition, the composition comprises cerium oxide in an amount of from about 98 wt% to about 70 wt%, based on the total weight of the particulate oxide composition.

[0080] It can be understood that a particulate oxide composition containing trivalent doped CeO2 having the described depth profile can have any of the above-mentioned amounts of trivalent dopant, cerium oxide, and any additional metal oxide.

[0081] In certain embodiments, the particulate oxide composition contains cerium oxide and a trivalent dopant, with trace to no (i.e., about 0) additional metal oxides, and only 1% to no (i.e., 0 or undetectable) impurities. If present and detectable, any impurities are generally present in amounts of about 100 ppm or less.

[0082] In certain embodiments, the particulate oxide composition has an average ratio of trivalent dopant to Ce from about 0 nm to about 3.5 nm from the surface of the particulate oxide composition that is about 10% to about 250% greater than the ratio of trivalent dopant to Ce from about 15 nm from the surface of the particulate oxide composition. In other embodiments, the particulate oxide composition has an average ratio of trivalent dopant to Ce from about 0 nm to about 3.5 nm from the surface of the particulate oxide composition that is about 15% to about 250% greater than the ratio of trivalent dopant to Ce from about 15 nm from the surface of the particulate oxide composition. As noted above, it is understood that the surface of the particulate oxide composition is defined as the region from the surface of the particulate oxide composition.

[0083] It can be understood that a particulate oxide composition containing trivalent doped CeO2 having the depth profile described above can also have the above amounts of trivalent dopant, cerium oxide, and any additional metal oxide, as well as any of the additional properties described below.

[0084] Particulate oxide compositions containing trivalent-doped CeO2 with unique depth profiles can also exhibit unique physical properties, including both physisorption and chemisorption of CO2 (see Figures 5A, 5B, and 5C). Physisorption, also known as physical adsorption, is a weak association, e.g., via van der Waals. Chemisorption, also known as chemical adsorption, occurs when adsorbed materials are held together by chemical bonds, which is much stronger than physisorption. The physisorption and chemisorption properties are unique features of particulate compositions containing trivalent-doped CeO2 with the depth profiles described above. Because the adsorbent is CO2 (an acid), the chemisorption properties indicate that the material is more basic, which may provide improved activity for removing biological contaminants. This physisorption and chemisorption property can be combined with any of the depth profiles described above, as well as any of the amounts of trivalent dopant, cerium oxide, and any additional metal oxides described above, as well as additional properties described below.

[0085] Particulate oxide compositions with unique depth profiles are also more easily reduced than compositions produced by prior art methods, and therefore are more oxidizing. Figure 6 shows graphs of temperature-programmed hydrogen reduction of materials from Examples 1, 2, and 3. Example 1 has a large, sharp peak at low temperatures. This peak indicates that this novel particulate oxide composition is more easily reduced compared to the compositions of Examples 2 or 3. Therefore, particulate oxide compositions with unique depth profiles may be more oxidizing and therefore more effective at removing / reducing biological contaminants. The graph for Example 2 has essentially the same shape as Example 1, but is shifted to higher temperatures, indicating that the material requires more energy to react with hydrogen and is therefore less oxidizing than Example 1. The graph for Example 3, which is undoped cerium oxide, shows two broad, but not very high, hydrogen reduction peaks. This indicates that there are two types of reduction that can occur with this material, with the higher temperature being much more difficult to achieve. Without wishing to be bound by any theory, it is believed that the unique depth profile of the particulate oxide composition, such that a higher ratio of trivalent dopant to Ce exists on and near the surface of the particulate material, may result in this change in hydrogen reduction temperature and increased oxidation properties. Furthermore, the increased oxidation properties of the particulate oxide composition with the unique depth profile can provide improved activity for removing biological contaminants. This property can also be combined with any of the depth profiles, physical properties, and any of the amounts of trivalent dopant, cerium oxide, and any additional metal oxides described above, as well as additional properties described below.

[0086] Particulate oxide compositions containing trivalent-doped CeO2 and having the unique depth profiles disclosed herein can further exhibit higher basicity, as indicated by their isoelectric point and zeta potential (see FIG. 7). In certain embodiments, the particulate oxide compositions described herein have an isoelectric point at a pH of about 8 to about 9. In further embodiments, the particulate oxide compositions described herein have a zeta potential of about 20 to about 40 mV at a pH of about 7. Having a higher isoelectric point indicates that the material is more basic and may provide improved activity for removing biological contaminants. This property can also be combined with any of the depth profiles, physical properties, and any of the above amounts of trivalent dopant, cerium oxide, and any additional metal oxide, as well as the additional properties described below.

[0087] Particulate oxide compositions including trivalent doped CeO2 can also have a surface area that assists in providing biological contaminant removal properties.

[0088] As described herein, surface area is the apparent surface area of ​​a composition determined using a Micromeritics ASAP 2000 system and nitrogen at approximately 77 Kelvin. The procedure outlined in ASTM International Test Method D 3663-03 (Reapproved 2008) was used, with one significant exception. It is well known that "BET surface area" determinations are impossible for materials containing microporous structures. Recognizing that surface area is an approximation, the reported values ​​are labeled "apparent surface area" values ​​rather than "BET surface area" values. Following generally accepted procedures, the application of the BET equation for determining apparent surface area was limited to a pressure range where the term na(lP / Po) increases continuously with P / Po. Samples were degassed under nitrogen at approximately 300°C for approximately two hours.

[0089] The particulate oxide composition containing trivalent doped CeO2 is approximately 70 m 2 / g~about 300m 2 / g. Without wishing to be bound by any theory, it is believed that surface area can influence and improve the removal of biological contaminants from gaseous or aqueous streams or by contact with solid surfaces.

[0090] It can be understood that a particulate oxide composition having this surface area, in combination with any one or more of the depth profile and other above-described properties, and any of the above-described amounts of trivalent dopant, cerium oxide, and optional additional metal oxide, can have an average pore volume as set forth below.

[0091] The particulate oxide composition is typically about 0.01 cm 3 / g ~ approx. 1.5cm 3 / g of average (mean, median, and mode) pore volume (as determined by N2 adsorption). Without wishing to be bound by any theory, it is believed that the average pore volume can influence and improve the removal of biological contaminants from aqueous or gaseous streams.

[0092] It can be understood that the particulate oxide composition can have the above-mentioned average pore volume in combination with any one or more of the above-mentioned surface area, depth profile, and other above-mentioned properties, and any of the above-mentioned amounts of trivalent dopant, cerium oxide, and any additional metal oxide.

[0093] Particulate oxide compositions containing cerium oxide and one or more trivalent dopants can effectively remove biological contaminants, and when used in blended compositions with silver-zinc zeolite, can even more effectively remove biological contaminants. The blended compositions can remove approximately 90% or more of the biological contaminants. In certain embodiments, the blended compositions can remove approximately 99% or more of the biological contaminants.

[0094] The blend compositions disclosed herein perform better than silver-zinc zeolite alone, allowing for reduced usage of silver-zinc zeolite while maintaining effectiveness in biological contaminant removal.

[0095] When the two components are used together, the blended composition can reduce the amount of silver-zinc zeolite while retaining activity, and the blended composition tends to exhibit better activity than either the silver-zinc zeolite or the particulate oxide composition alone. Thus, the blended composition exhibits unexpected synergy for removing / reducing biological contaminants.

[0096] The novel blend composition contains a silver-zinc zeolite and a particulate oxide composition (both described above). The blend composition comprises the silver-zinc zeolite in an amount of from about 1 wt. % to less than about 50 wt. %, based on the total weight of the blend composition, and the particulate oxide composition in an amount of from about 50 wt. % to about 99 wt. %, based on the total weight of the blend composition. In certain embodiments, the blend composition comprises from about 10 wt. % to about 25 wt. % of the silver-zinc zeolite and from about 75 wt. % to about 90 wt. % of the particulate oxide composition.

[0097] In the blend composition, the silver zinc zeolite is present in a minor amount relative to the particulate oxide composition. The particulate oxide composition in the blend composition includes all of the particulate oxide composition embodiments described above. In particular, the particulate oxide composition in the blend composition is one having a unique depth profile as described herein.

[0098] The blended composition can be slurried with an aqueous stream containing biological contaminants to effectively remove the biological contaminants. In some embodiments, slurrying the blended composition with the aqueous stream removes at least about 90% of the biological contaminants. In other embodiments, the slurrying removes at least 95%, or more preferably 99% or 99%+ of the biological contaminants.

[0099] The blend compositions described herein can also be incorporated into support compositions and / or articles for removing biological contaminants, as described below.

[0100] Support compositions and articles Also disclosed herein are support compositions for removing biological contaminants, including a support material and a blend composition containing a silver-zinc zeolite and a trivalent-doped CeO particulate composition. The support compositions include a support material and a blend composition containing a silver-zinc zeolite and a particulate oxide composition containing cerium oxide doped with a trivalent dopant selected from the group consisting of yttrium (Y), lanthanum (La), neodymium (Nd), praseodymium (Pr), and mixtures thereof, and optionally an additional metal oxide selected from the group consisting of aluminum (Al), titanium (Ti), zirconium (Zr), hafnium (Hf), and mixtures thereof, wherein the cerium oxide is present in an amount greater than the trivalent dopant.

[0101] As described, the particulate oxide composition includes a particulate oxide composition comprising cerium oxide, one or more trivalent dopants (as oxides), and optionally additional metal oxides other than the cerium oxide and the trivalent dopants, and / or trace amounts of impurities. In certain embodiments, the particulate oxide composition contains about 0 additional metal oxides. The particulate oxide composition has a unique depth profile, in which the cerium oxide is present in an amount greater than the trivalent dopant, and the average ratio of trivalent dopant to Ce from about 0 nm to about 3.5 nm from the surface of the particulate oxide composition is greater than the ratio of trivalent dopant to Ce from about 15 nm from the surface of the particulate oxide composition. The particulate oxide composition of the blend composition in the support composition includes all of the above-described embodiments of the particulate oxide composition.

[0102] The support composition for removing biological contaminants also includes a support material, which includes an organic polymer, cotton, fiberglass, or a mixture thereof.

[0103] The organic polymer may be a homopolymer or copolymer of organic monomers. The organic polymer may be a silicone or polysiloxane (i.e., a polymer composed of siloxane (—R2Si—O—SiR2—), where R is an organic group). The organic polymer may also be a thermosetting polymer, such as a thermoplastic elastomer. In certain embodiments, the organic polymer is selected from the group consisting of polyethylene, polycarbonate, polyvinyl chloride, nylon, polypropylene, polyester, polyurethane, polyamide, polyolefin, copolymers thereof, and mixtures thereof. In certain embodiments, the organic polymer is silicone.

[0104] In the support compositions disclosed herein, the blend composition is deposited on or within a support material.

[0105] In one embodiment of the support composition, the particulate oxide composition of the blend composition comprises cerium oxide in an amount of about 99.9 wt % to about 20 wt %, based on the total weight of the particulate oxide composition; a trivalent dopant (as the oxide) in an amount of about 0.1 wt % to about 50 wt %, based on the total weight of the particulate oxide composition; and an additional metal oxide in an amount of about 70 wt % to about 0 wt %, based on the total weight of the particulate oxide composition.

[0106] In another embodiment of this support composition, the particulate oxide composition of the blend composition comprises from about 0.1 wt % to about 50 wt % trivalent dopant and from about 99.9 wt % to about 50 wt % cerium oxide, based on the total weight of the particulate oxide composition.

[0107] In yet another embodiment of this support composition, the particulate oxide composition of the blend composition comprises cerium oxide in an amount of about 20 wt % to about 30 wt %, based on the total weight of the particulate oxide composition; a trivalent dopant in an amount of about 2 wt % to about 25 wt %, based on the total weight of the particulate oxide composition; and an additional metal oxide in an amount of about 45 wt % to about 78 wt %, based on the total weight of the particulate oxide composition.

[0108] In a further embodiment of this support composition, the particulate oxide composition of the blend composition comprises cerium oxide in an amount of about 45 wt % to about 78 wt %, based on the total weight of the particulate oxide composition; a trivalent dopant in an amount of about 2 wt % to about 25 wt %, based on the total weight of the particulate oxide composition; and an additional metal oxide in an amount of about 20 wt % to about 30 wt %, based on the total weight of the particulate oxide composition.

[0109] It will be understood that in these support compositions, the blended composition can have any of the above-mentioned amounts of particulate oxide composition and silver zinc zeolite.

[0110] These support compositions include a support material comprising an organic polymer, cotton, glass fiber, or a mixture thereof, and a blend composition containing silver-zinc zeolite and a particulate oxide composition having a unique depth profile. As described, the particulate oxide composition is a mixed oxide composition (i.e., a mixture of oxides of cerium, a trivalent dopant, and optionally additional metal oxides).

[0111] In these support compositions, a blend composition containing silver-zinc zeolite and a particulate oxide composition (i.e., trivalent-doped cerium oxide having a unique depth profile) is deposited on or within a support material, and the particulate oxide composition of the support composition includes all of the above-described embodiments, including all of the properties and any of the above-described amounts of trivalent dopant, cerium oxide, and any additional metal oxide.

[0112] In all embodiments, the support composition contains from about 0.5 to about 80 wt. % of the blend composition, based on the total weight of the support composition. In certain embodiments, the support composition contains from about 0.5 to about 50 wt. % of the blend composition, based on the total weight of the support composition. In other embodiments, the support composition contains from about 0.5 to about 25 wt. % of the blend composition, based on the total weight of the support composition. In still other embodiments, the support composition contains from about 0.5 to about 10 wt. % of the blend composition, based on the total weight of the support composition. In further embodiments, the support composition contains from about 0.5 to about 5 wt. % of the blend composition, based on the total weight of the support composition. It is understood that in these support compositions, the blend composition can have any of the above-described amounts of the particulate oxide composition and the silver-zinc zeolite.

[0113] The support composition, including the support material and the blend composition, can be in a rigid or elastic form. The support composition can form an article for removing biological contaminants, such as a filter or plastic (e.g., a plastic container). The article can be in a rigid or elastic form.

[0114] When the support composition forms an article, the article contains from about 50 to about 100 weight percent of the support composition containing the support material and the blend composition, based on the total weight of the article. In certain embodiments, the article contains from about 75 to about 95 weight percent of the support composition containing the support material and the blend composition, based on the total weight of the article.

[0115] When the blend composition and substrate are formed into a flexible or rigid article, the article may also include binders, sand, gravel, glass wool, metal or plastic containers, and the like.

[0116] In some embodiments, the support material may be an organic polymer. In certain of these embodiments, the trivalent dopant of the particulate oxide composition is Pr, La, or a mixture thereof. When the support composition using an organic polymer as the support material forms an article, the article may be a plastic article. In these embodiments, the organic polymer may be selected from the group consisting of polyethylene, polyvinyl chloride (PVC), nylon, polypropylene, polyester, polyurethane, polyamide, polyolefin, polycarbonate, copolymers thereof, and mixtures thereof. In certain embodiments, the organic polymer is polyethylene, polycarbonate, or a mixture thereof. If plastic, the article may be in the form of a filter, bottle, container, or plastic cover for a high-touch service. The filter may be a fixed bed. The bottle or container may be for liquids. High-touch surfaces include escalator or staircase handrail covers, elevator button covers, doors, door handles or knobs or covers therefor, public transportation covers, touchpads for electronic transactions, etc.

[0117] In some embodiments, the support material may be cotton. In certain of these embodiments, the trivalent dopant of the particulate oxide composition is Pr, La, or a mixture thereof. When this support composition using cotton as the support material is formed into an article, the article may be a filter or a fabric.

[0118] In some embodiments, the support material may be glass fiber. In certain of these embodiments, the trivalent dopant of the particulate oxide composition is Pr, La, or a mixture thereof. When this support composition using glass fiber as the support material forms an article, the article may be a filter, a bottle, a container, or a high-frequency touch surface. The filter may be a fixed bed. High-frequency touch surfaces include elevator button covers, doors, public transportation covers, electronic transaction touchpads, etc.

[0119] In certain embodiments, the support material may be cotton and an organic polymer. In certain of these embodiments, the organic polymer may be selected from the group consisting of nylon, polyester, polyamide, and mixtures thereof. In certain of these embodiments, the trivalent dopant of the particulate oxide composition is Pr, La, or a mixture thereof. When this mixture as a support material forms an article, the article may be a filter or a fabric.

[0120] In certain embodiments, the support material may be glass fiber and an organic polymer. The organic polymer may be selected from the group consisting of polyethylene, polyvinyl chloride (PVC), nylon, polypropylene, polyester, polyurethane, polyamide, polyolefin, polycarbonate, copolymers thereof, and mixtures thereof. In certain of these embodiments, the organic polymer may be selected from the group consisting of polyethylene, polycarbonate, and mixtures thereof. In certain of these embodiments, the trivalent dopant of the particulate oxide composition is Pr, La, or a mixture thereof. When this mixture as a support material forms an article, the article may be a filter, a bottle, a container, or a high-frequency touch surface. The filter may be a fixed bed. High-frequency touch surfaces include escalator or staircase handrail covers, elevator button covers, door, door handle or knob covers, public transportation covers, touchpads for electronic transactions, etc.

[0121] In some embodiments, the support material may be polyethylene or polycarbonate. In certain of these embodiments, the trivalent dopant of the particulate oxide composition is Pr, La, or a mixture thereof. When the support composition forms an article, the article may be a plastic article and may be in the form of a filter, a bottle, a container, or a plastic cover for a high-touch surface. The filter may be a fixed bed.

[0122] In certain embodiments, the support material may be silicone. In certain of these embodiments, the trivalent dopant of the particulate oxide composition is Pr, La, or a mixture thereof.

[0123] In certain embodiments, the article is a plastic article. The plastic article may be in the form of a filter, a bottle, a container, or a plastic cover for a high-touch surface. The plastic article comprises a support composition for removing biological contaminants, the support composition comprising an organic polymer selected from the group consisting of polyethylene, polyvinyl chloride, nylon, polypropylene, polyester, polyurethane, polyamide, polyolefin, polycarbonate, copolymers thereof, and mixtures thereof. The plastic article further comprises a blend composition comprising (i) a silver-zinc zeolite and (ii) a particulate oxide composition comprising cerium oxide; a trivalent dopant selected from the group consisting of yttrium (Y), lanthanum (La), neodymium (Nd), praseodymium (Pr), and mixtures thereof; and optionally, an additional metal oxide selected from the group consisting of aluminum (Al), titanium (Ti), zirconium (Zr), hafnium (Hf), and mixtures thereof, wherein the cerium oxide is present in an amount greater than the trivalent dopant, and the average ratio of trivalent dopant to Ce from about 0 nm to about 3.5 nm from the surface of the particulate oxide composition is greater than the ratio of trivalent dopant to Ce from about 15 nm from the surface of the particulate oxide composition. In certain of these embodiments, the trivalent dopant of the particulate oxide composition is Pr, La, or a mixture thereof. Further, in certain of these embodiments of the plastic article, the organic polymer may be selected from the group consisting of polyethylene, polycarbonate, and mixtures thereof.

[0124] In all embodiments of the plastic article, the blend composition is deposited on or within an organic polymer. In certain embodiments, the plastic article comprises about 50 to about 100 weight percent of the support composition for removing biological contaminants, based on the total weight of the plastic article.

[0125] A particular embodiment of the plastic article comprises a blend composition comprising (i) a silver-zinc zeolite and (ii) a particulate oxide composition comprising from about 0.1 wt % to about 50 wt % of a trivalent dopant, and from about 99.9 wt % to about 50 wt % of cerium oxide, based on the total weight of the particulate oxide composition. This particular particulate oxide composition includes all of the particulate oxide composition embodiments described above.

[0126] The blend compositions, support compositions, and articles comprising the silver-zinc zeolite and trivalent-doped cerium oxide particulate compositions disclosed herein can remove about 90% or more of biological contaminants. In certain embodiments, the blend compositions, support compositions, and articles disclosed herein can remove approximately 99% or more of biological contaminants.

[0127] Biological contaminants removed by the articles, support compositions, blend compositions, and methods disclosed herein include viruses, bacteria, fungi (e.g., mold or fungus), protozoa (e.g., amoeba), algae, yeast, etc., and mixtures thereof. In certain embodiments, the biological contaminants removed by the articles, compositions, and methods disclosed herein are selected from the group consisting of bacteria, viruses, fungi (e.g., mold), protozoa (e.g., amoeba), and mixtures thereof. In certain embodiments, the biological contaminants removed by the articles, compositions, and methods disclosed herein are bacteria, viruses, amoeba, and mixtures thereof. In other embodiments, the biological contaminants are bacteria, viruses, and mixtures thereof.

[0128] In certain embodiments, biological contaminants removed include substances of concern in aqueous streams such as wastewater, and airborne substances of concern.

[0129] Bacteria include gram-positive and gram-negative bacteria. Bacteria include those commonly found in water, including fecal coliforms. Bacteria include, for example, Streptococcus, Staphylococcus, Escherichia coli, Methicillin-resistant Staphylococcus aureus (MRSA), Legionella pneumophila, Campylobacter jejuni, Salmonella, Mycobacterium tuberculosis, Corynebacterium diphtheriae, Listeria monocytogenes, Bordetella pertussis, and the like. Viruses include, for example, rhinoviruses, coronaviruses, vaccinia, polioviruses, varicella-zoster viruses, paramyxoviruses, influenza viruses, morbilliviruses, hepatitis A viruses (HAV), adenoviruses (HAdV), rotaviruses (RoV), sapoviruses, respiratory syncytial viruses (RSV), paramyxoviruses, varicella-zoster viruses (VZV), variola viruses (including smallpox and monkeypox), and other enteric viruses such as noroviruses (NoV), coxsackieviruses, echoviruses, reoviruses, and astroviruses. Other microbial contaminants include protozoa (e.g., Cryptosporidium), particularly amoebas (e.g., Naegleria fowleri). Further microbial contaminants that are fungi include Trichophyton mentagrophytes and Aspergillus.

[0130] The articles, compositions and methods disclosed herein reduce the concentration or amount of these biological contaminants.

[0131] Method for making trivalent doped cerium oxide particulate oxide composition There are known methods for producing trivalent doped cerium oxide compositions (see, for example, U.S. patent application Ser. No. 17 / 870,068, filed July 21, 2021, entitled "Use of Trivalent Doped Cerium Oxide Compositions for Biological Contaminant Removal," the entire contents of which are incorporated herein by reference). Methods for producing trivalent doped cerium oxide compositions having the unique depth profiles described herein are described in U.S. patent application Ser. No. 17 / 895,942, filed August 25, 2022, entitled "Trivalent Doped Cerium Oxide Compositions for Biological Contaminant Removal," the entire contents of which are incorporated herein by reference.

[0132] Preparation of Blend Composition The blend compositions disclosed herein contain a particulate oxide composition and a silver zinc zeolite.

[0133] A method for preparing a blended composition includes physically mixing silver-zinc zeolite with a particulate oxide composition. As an example, silver-zinc zeolite can be mixed with a particulate oxide composition to obtain a blended composition. In some embodiments, the blended composition is about 10 wt. % silver-zinc zeolite and about 90 wt. % particulate oxide composition. Physical mixing can be accomplished by placing the silver-zinc zeolite and the particulate oxide composition in a sealed container, which is then shaken, repeatedly inverted, tumbled, or similarly operated. Alternatively, physical mixing can be accomplished by placing the silver-zinc zeolite and the particulate oxide composition in a device designed for mixing dry powder materials, such as a blender or paddle mixer. In either mixing method, mixing should be performed for an amount of time sufficient to achieve a homogeneous mixture of the materials.

[0134] Preparation of Support Compositions and Articles The support composition includes a support material and a blend composition of silver-zinc zeolite and a particulate oxide composition. The particulate oxide composition includes cerium oxide and a trivalent dopant and has a unique depth profile as described above. The particulate oxide composition may optionally include additional metal oxides other than cerium oxide and a trivalent dopant. The particulate oxide composition, blend composition, support composition, and article include all of the embodiments described herein. In the support composition, the support material is selected from an organic polymer, cotton, glass fiber, or a mixture thereof.

[0135] The support composition can be used independently to treat gaseous or aqueous mixtures, or it can be incorporated into an article specifically designed for treating gaseous or aqueous mixtures, such as a filter or plastic container. The filter can be a fixed bed. The filter can be used for gaseous or aqueous mixtures or streams, and thus for filtering gaseous or aqueous mixtures or streams.

[0136] In support compositions and articles containing the support composition, the blend composition is deposited on or within a support material to provide a support composition for removing biological contaminants.

[0137] The blend composition can be deposited on one or more outer and / or inner surfaces of a support material. Those skilled in the art will understand that the inner surfaces of a support material are generally referred to as pores. The blend composition described herein can be supported on a support material with or without a binder. In some embodiments, the blend composition can be applied to the support material using any conventional technique, such as slurry deposition.

[0138] The process for preparing the support composition is not limited by any particular steps or methods and can generally be any that results in the incorporation of the blend composition into or deposition on a support material. The process for incorporating the blend composition into the support material includes mixing the blend composition to produce the support material. As an example, the blend composition can be added to molten polypropylene in a molding process. As another example, the blend composition can be added to a mixture of polyvinyl chloride resin, plasticizer, and stabilizer, and passed through a hot mixer and then an extruder.

[0139] The process of depositing the blend composition onto a support material involves mixing the blend composition with an organic binder, either as a liquid or in an aqueous solution. The blend composition and organic binder mixture is then bonded to the support material by immersing the support material or by coating the support material with the mixture by spreading or airbrushing. The organic binder can also be used in a slurry deposition technique.

[0140] In certain embodiments, the organic binder is selected from the group consisting of citric acid, polyurethane diol, polyvinyl alcohol, polyvinylpyrrolidone, linseed oil, and mixtures thereof. Once the blend composition is bonded to the support material, the coated substrate can optionally be rinsed with water before drying to remove any residue not bonded to the substrate. The coated substrate can then be optionally dried at a temperature above about 20°C and below about 300°C for about 1 to 12 hours, or until sufficiently dry. In certain embodiments, the coated substrate can then be optionally dried at a temperature above about 20°C and below about 120°C.

[0141] In the case of a meltable support material, such as glass or plastic, the support can be heated to the point where the surface just begins to soften, and then the blend composition can be placed on the surface so that it begins to mix with the semi-molten material. Upon cooling and resolidification, the blend composition is incorporated into the surface of the support material. The temperature utilized will depend on the support material utilized. One skilled in the art will be able to readily determine the appropriate temperature for the support material utilized. For example, this temperature for quartz glass is over 1000°C, for borosilicate glass it is about 500-600°C, and for PVC it ​​is about 200-300°C.

[0142] These solid supports can be utilized to form articles, including filters and plastic articles.

[0143] The blend composition may also be incorporated into articles for high-touch surfaces, which may come into contact with biological contaminants through direct touch contact. Thus, articles for high-touch surfaces may also be used not only for fluid treatment but also for reducing bacteria and / or viruses deposited through contact. These articles may be liquid containers, elevator buttons, handrail covers for escalators or stairs, doors, door handles, door knobs, covers for public transportation, touchpads for electronic transactions, fabrics, etc.

[0144] The support composition containing the blend composition and the support material can be formed into a flexible or rigid article, such as a filter, a fixed bed filtration system, a bottle or container, a high-touch surface, etc. In certain embodiments, the article is a plastic article. In other embodiments, the article is a filter. These articles may contain any additional necessary components that such articles typically contain, as will be well recognized by those skilled in the art. Techniques for forming these articles are well known to those skilled in the art.

[0145] Methods for Using the Blend Composition This application relates to methods for removing biological contaminants using any of the disclosed compositions containing a blend composition of trivalent-doped cerium oxide and silver-zinc zeolite. The methods can utilize the blend composition itself, or the methods can utilize the blend composition as part of a support composition or article. The methods can treat fluids, including air streams, aqueous streams, and gaseous streams.

[0146] Without wishing to be bound by any theory, the unique depth profile of the particulate oxide composition in the blended composition (such that there is a higher ratio of trivalent dopant to cerium on and near the surface of the particulate composition) may provide improved activity for removing biological contaminants. Surprisingly, the blended composition has higher activity than either the silver zinc zeolite alone or the particulate oxide composition alone.

[0147] In some embodiments, the support composition comprising the blend composition and the support material may be used independently in a method for removing biological contaminants, or the support composition of the blend composition and the support material may be incorporated into an article, such as a filter or plastic (such as a plastic container), specifically designed to treat gaseous or aqueous mixtures.

[0148] As described herein, in the blend composition, the particulate oxide composition comprises cerium oxide; a trivalent dopant selected from the group consisting of yttrium (Y), lanthanum (La), neodymium (Nd), praseodymium (Pr), and mixtures thereof; and optionally, an additional metal oxide selected from the group consisting of aluminum (Al), titanium (Ti), zirconium (Zr), hafnium (Hf), and mixtures thereof, wherein the cerium oxide is present in an amount greater than the trivalent dopant, and the average ratio of the trivalent dopant to Ce from about 0 nm to about 3.5 nm from the surface of the particulate oxide composition is greater than the ratio of the trivalent dopant to Ce from about 15 nm from the surface of the particulate oxide composition. In these methods, it can be understood that the particulate oxide composition can have any of the above-described amounts of the trivalent dopant, cerium oxide, and any additional metal oxide, and any of the above-described properties, and the blend composition can have any of the above-described amounts of the silver-zinc zeolite and the particulate oxide composition.

[0149] In certain method embodiments, the present application relates to methods for removing biological contaminants and ensuring biological contaminants at or below target levels using the disclosed blend compositions containing silver-zinc zeolite and trivalent-doped cerium oxide. These biological contaminants include bacteria, viruses, protozoa (e.g., amoeba), fungi, algae, yeast, etc. These methods use the blend compositions themselves, support compositions containing the blend compositions, and articles containing support compositions containing the blend compositions.

[0150] The methods can treat a fluid (e.g., an aqueous stream, a gaseous stream, or a mixture thereof) or the surface of a solid object by touch / direct contact. Thus, the methods disclosed herein include methods for treating a fluid (e.g., an aqueous stream and / or a gaseous stream).

[0151] In certain embodiments of the method, an aqueous or gaseous stream is contacted with a blend composition of silver zinc zeolite and a particulate oxide composition, including any of the above-described embodiments, including any of the above-described amounts of trivalent dopant, cerium oxide, and any additional metal oxide, and any of the above-described properties.

[0152] In other method embodiments, an aqueous stream or a gaseous stream is contacted with a support composition containing a blend composition described herein. In yet other method embodiments, a potentially contaminated surface is contacted with a support composition or article containing a blend composition described herein. These potentially contaminated surfaces include, for example, skin (e.g., hands, fingers, palms, etc.), where contact is by touching a support composition or article containing a blend composition described herein. In the disclosed methods, the biological contaminants to be removed may be contained in an aqueous stream or gaseous stream, or may be on the surface of a physical object.

[0153] Without wishing to be bound by any theory, it is believed that contact of biological contaminants with a blended composition containing the silver-zinc zeolite and particulate oxide composition described herein results in one or more of adsorption and / or reaction with the silver-zinc zeolite and / or trivalent-doped cerium oxide, or inactivation upon contact with the silver-zinc zeolite and / or trivalent-doped cerium oxide. By adsorbing, reacting, and / or inactivating the biological contaminants with the silver-zinc zeolite and / or trivalent-doped cerium oxide, the biological contaminants are removed from biological contaminant-containing fluids (air or aqueous streams) or solid surfaces. Without wishing to be bound by any theory, the unique depth profile of the particulate oxide composition, which provides a higher ratio of trivalent dopant to cerium at and near the surface, may provide improved activity for removing biological contaminants. It is surprising that the blended composition exhibits improved activity compared to the silver-zinc zeolite or the particulate oxide composition alone.

[0154] Biological contaminants can be removed to a target level or below a target level. In some embodiments, biological contaminants can be removed to an undetectable level. The target level may be a specified amount or detection limit. As part of the methods described herein, the biological contaminants to be removed may be identified and a target amount or level of the contaminant may be set. For certain of the biological contaminants contemplated herein, the target amount or level may be any detectable amount. The method may optionally further include monitoring the treated stream for contaminants.

[0155] The methods disclosed herein may be used to treat air or water, or to treat contaminants by contact with the touch, where the disclosed blend compositions are incorporated into high-touch surfaces.

[0156] The use of the disclosed blend compositions to treat biologically contaminated air and / or water allows for efficient operation of the air and / or water treatment process and provides treated streams with reduced concentrations of biological contaminants. As disclosed herein, the blend compositions may be incorporated into support compositions, which may in turn be incorporated into articles specifically designed to treat gaseous or aqueous mixtures, such as filters, fixed-bed filtration systems, or plastic containers. In methods for treating aqueous streams, the blend compositions themselves may also be used and contacted by slurrying. In those methods involving slurrying, the method may further include filtering the fluid / liquid.

[0157] In any of these methods, the particulate oxide composition in the blend composition can have any of the above-described amounts of trivalent dopant, cerium oxide, and any additional metal oxide, and any of the above-described properties. The particulate oxide composition in the blend composition has a unique depth profile. The blend composition can also have any of the above-described amounts of silver zinc zeolite and particulate oxide composition.

[0158] While the method of the present disclosure is contemplated for removing biological (e.g., bacterial, viral, amoeba, etc.) contaminants from air and / or drinking water and groundwater, it will be understood that the process can be used to treat any gaseous or aqueous liquid feed containing undesirable amounts of biological contaminants. The method is also contemplated for removing biological contaminants by direct contact of the contaminated surface with an article containing the blend composition described herein.

[0159] In certain embodiments, these methods of removing biological contaminants include: (i) providing a blended composition comprising: (a) a silver-zinc zeolite; and (b) a particulate oxide composition comprising cerium oxide; a trivalent dopant selected from the group consisting of yttrium (Y), lanthanum (La), neodymium (Nd), praseodymium (Pr), and mixtures thereof; and optionally an additional metal oxide selected from the group consisting of aluminum (Al), titanium (Ti), zirconium (Zr), hafnium (Hf), and mixtures thereof, wherein the cerium oxide is present in an amount greater than the trivalent dopant, and wherein the average ratio of trivalent dopant to Ce from about 0 nm to about 3.5 nm from the surface of the particulate composition is greater than the ratio of trivalent dopant to Ce at about 15 nm from the surface of the particulate composition; (ii) contacting the blended composition with a biological contaminant selected from the group consisting of bacteria, viruses, fungi, protozoa, and mixtures thereof; and (iii) removing the biological contaminant by contact with the blended composition. The biological contaminants may be contained in an aqueous or liquid stream or on the surface of an object that comes into physical contact with the blend composition. These methods remove at least about 90% of the biological contaminants upon contact with the blend composition.

[0160] In some embodiments, the blend composition may be included within a support composition, and in certain of these embodiments, the support composition may be incorporated into an article. These methods may further include monitoring for biological contaminants after contact. Monitoring may be by sampling or may be continuous.

[0161] In certain embodiments, the method includes (i) a support material comprising an organic polymer, cotton, glass fiber, or a mixture thereof, and a blend composition, the blend composition comprising: (a) a silver zinc zeolite and (b) a trivalent dopant selected from the group consisting of cerium oxide; yttrium (Y), lanthanum (La), neodymium (Nd), praseodymium (Pr), and mixtures thereof; and, optionally, an additional metal oxide selected from the group consisting of aluminum (Al), titanium (Ti), zirconium (Zr), hafnium (Hf), and mixtures thereof. The methods include (i) providing a support composition comprising a particulate oxide composition, wherein cerium oxide is present in an amount greater than the trivalent dopant, and wherein the average ratio of trivalent dopant to cerium from about 0 nm to about 3.5 nm from the surface of the particulate composition is greater than the ratio of trivalent dopant to cerium from about 15 nm from the surface of the particulate composition; (ii) contacting the support composition with a biological contaminant selected from the group consisting of bacteria, viruses, fungi (e.g., molds), protozoa (e.g., amoebas), and mixtures thereof; and (iii) removing the biological contaminant by contact with the support composition. These methods remove at least about 90% of the biological contaminant.

[0162] In some of these methods, the particulate oxide composition in the blend composition comprises cerium oxide in an amount of about 99.9 wt % to about 20 wt %, based on the total weight of the particulate oxide composition; a trivalent dopant in an amount of about 0.1 wt % to about 50 wt %, based on the total weight of the particulate oxide composition; and an additional metal oxide in an amount of about 70 wt % to about 0 wt %, based on the total weight of the particulate oxide composition.

[0163] The biological contaminant may be contained in the aqueous or liquid stream or on the surface of an object that comes into physical contact with the support composition. The methods may further include monitoring for the biological contaminant after contact. Monitoring may be by sampling or may be continuous.

[0164] The blended compositions include all of the above embodiments, including silver zinc zeolite and particulate oxide compositions in any of the above amounts, and the particulate oxide compositions used include any of the above amounts of trivalent dopant, cerium oxide, and any additional metal oxides, and any of the above properties. The particulate compositions with unique depth profiles, in combination with silver zinc zeolite, can reduce concentrations of biological contaminants, among other things.

[0165] Contacting the blend composition with the biological contaminant results in a measurable removal of the biological contaminant. In some embodiments, the contact removes at least about 90% of the biological contaminant. In other embodiments, the contact removes at least 95%, or more preferably 99% or 99%+ of the biological contaminant.

[0166] Contacting the blend composition with a biological contaminant effectively reduces the amount of the biological contaminant, and in certain embodiments, effectively reduces the amount of biological contaminant in a gaseous or aqueous stream. Removal can also be expressed as a percentage reduction in the concentration of the biological contaminant. In some embodiments, contacting the blend composition with a biological contaminant can reduce its concentration by more than about 75%. More typically, contacting the blend composition with a biological contaminant can reduce its concentration by more than about 80%, more typically by more than about 85%, more typically by more than about 90%, more typically by more than about 95%, more typically by more than about 97.5%, more typically by more than about 99%, and even more typically by more than about 99.5%.

[0167] In certain embodiments, these methods may be for removing biological contaminants from a fluid or for treating a fluid. In these embodiments, the fluid may be a gaseous, aqueous stream, or a mixture thereof. In these embodiments, the method may use either the blend composition itself, a support composition, or an article described herein. Thus, the method includes (i) providing a blend composition, support composition, or article described herein. In the case of a support composition, the support material includes an organic polymer, cotton, glass fiber, or a mixture thereof. The blend composition comprises (a) a silver-zinc zeolite and (b) a particulate oxide composition comprising cerium oxide; a trivalent dopant selected from the group consisting of yttrium (Y), lanthanum (La), neodymium (Nd), praseodymium (Pr), and mixtures thereof; and optionally an additional metal oxide selected from the group consisting of aluminum (Al), titanium (Ti), zirconium (Zr), hafnium (Hf), and mixtures thereof, wherein the cerium oxide is present in an amount greater than the trivalent dopant, and the average ratio of trivalent dopant to Ce from about 0 nm to about 3.5 nm from the surface of the particulate composition is greater than the ratio of trivalent dopant to Ce from about 15 nm from the surface of the particulate composition. The methods further include (ii) contacting a gaseous or aqueous stream containing a biological contaminant selected from the group consisting of bacteria, viruses, fungi (e.g., molds), protozoa (e.g., amoebas), and mixtures thereof, with the blended composition; and (iii) removing the biological contaminant from the gaseous or aqueous stream by contact with the blended composition. The biological contaminant may be removed in an amount of 90% or greater. These methods may further include monitoring the biological contaminant after contact. Monitoring may be by sampling or may be continuous.

[0168] In these methods, the blend composition and the particulate oxide composition in the blend composition include all of the above embodiments. The particulate oxide composition can reduce the concentration of biological contaminants in combination with silver zinc zeolite.

[0169] In these methods of treating gaseous or aqueous streams, the methods may further include setting a target concentration for a biological contaminant. In these methods, a biological contaminant of interest is identified and then a target concentration for that biological contaminant is set. The methods may further include monitoring the biological contaminant in the treated stream. Monitoring may be by sampling or may be continuous.

[0170] In certain embodiments, the method includes (i) providing a support material comprising an organic polymer, cotton, glass fiber, or a mixture thereof, and a particulate oxide composition comprising: cerium oxide; a trivalent dopant selected from the group consisting of yttrium (Y), lanthanum (La), neodymium (Nd), praseodymium (Pr), and mixtures thereof; and optionally, an additional metal oxide selected from the group consisting of aluminum (Al), titanium (Ti), zirconium (Zr), hafnium (Hf), and mixtures thereof, wherein the cerium oxide is present in an amount greater than the trivalent dopant, and the trivalent dopant is present in a region between about 0 nm and about 3.5 nm from the surface of the particulate composition. The method includes the steps of: (i) providing a particulate oxide composition, wherein an average ratio of trivalent dopant to Ce is greater than the ratio of trivalent dopant to Ce at about the surface of the particulate composition; (ii) establishing a target concentration of biological contaminants; (iii) contacting a gaseous or aqueous stream with the composition and removing the biological contaminants by contact with the composition to provide a treated stream; and (iv) monitoring the treated stream for biological contaminants selected from the group consisting of bacteria, viruses, fungi (e.g., molds), protozoa (e.g., amoeba), and mixtures thereof. The particulate oxide composition used in these methods includes all of the embodiments described above. The target concentration can be set to a fixed amount of contaminant (e.g., virus, bacteria, protozoa / amoeba, or fungi) or can be set to a detection limit. Monitoring of biological contaminants can be performed by techniques well known to those skilled in the art. Monitoring can be performed by sampling or continuously. Those skilled in the art understand real-time and continuous monitoring techniques for microbial contaminants, including viruses, bacteria, protozoa / amoeba, fungi, etc. These techniques include optical techniques and cell counters.

[0171] In certain embodiments for treating an aqueous stream, the method includes (i) providing a particulate composition comprising: (a) a silver-zinc zeolite and (b) a trivalent dopant selected from the group consisting of cerium oxide; yttrium (Y), lanthanum (La), neodymium (Nd), praseodymium (Pr), and mixtures thereof; and optionally, an additional metal oxide selected from the group consisting of aluminum (Al), titanium (Ti), zirconium (Zr), hafnium (Hf), and mixtures thereof, wherein the cerium oxide is present in an amount greater than the trivalent dopant; (ii) contacting an aqueous stream with the blended composition and removing biological contaminants from the blended composition to provide a treated aqueous stream, wherein the biological contaminants are selected from the group consisting of bacteria, viruses, fungi (e.g., molds), protozoa (e.g., amoebas), and mixtures thereof. These methods may further include monitoring the biological contaminants after contact. The monitoring may be performed by sampling or may be continuous. In certain embodiments, the method may further include setting a target concentration of the biological contaminant and monitoring the treated aqueous stream for the biological contaminant. The target concentration may be a specified amount or detection limit. In these methods, the blended composition may be contained within a support composition or within an article, or the blended composition itself may be contacted with the aqueous stream by slurrying it. In processes involving slurrying, the process may further comprise filtering the fluid / liquid. The blend compositions and particulate oxide compositions therein used in these processes include all of the embodiments described above.

[0172] In certain embodiments for treating an aqueous stream, the method includes: (i) a support material comprising an organic polymer, cotton, glass fiber, or a mixture thereof; and (a) a silver-zinc zeolite and (b) a trivalent dopant selected from the group consisting of cerium oxide; yttrium (Y), lanthanum (La), neodymium (Nd), praseodymium (Pr), and mixtures thereof; and optionally, an additional metal oxide selected from the group consisting of aluminum (Al), titanium (Ti), zirconium (Zr), hafnium (Hf), and mixtures thereof, wherein the cerium oxide is more soluble than the trivalent dopant. and (ii) a blend composition comprising a particulate composition, wherein the trivalent dopant to Ce is present in a high amount, and the average ratio of trivalent dopant to Ce from about 0 nm to about 3.5 nm from the surface of the particulate composition is greater than the ratio of trivalent dopant to Ce from about 15 nm from the surface of the particulate composition; and (ii) contacting an aqueous stream with the blend composition and removing biological contaminants by contact with the blend composition to provide a treated aqueous stream, wherein the biological contaminants are selected from the group consisting of bacteria, viruses, fungi (e.g., molds), protozoa (e.g., amoebas), and mixtures thereof. The blend composition and particulate oxide composition used in these methods include all of the embodiments described above. These methods may further include monitoring the biological contaminant after contact. Monitoring may be by sampling or may be continuous. In certain embodiments, the method may further include setting a target concentration of the biological contaminant and monitoring the treated aqueous stream for the biological contaminant. The target concentration may be a specified amount or detection limit.

[0173] In certain embodiments for treating a gaseous stream, the method includes: (i) a support material comprising an organic polymer, cotton, glass fiber, or a mixture thereof; and (a) a silver-zinc zeolite and (b) a trivalent dopant selected from the group consisting of cerium oxide; yttrium (Y), lanthanum (La), neodymium (Nd), praseodymium (Pr), and mixtures thereof; and optionally, an additional metal oxide selected from the group consisting of aluminum (Al), titanium (Ti), zirconium (Zr), hafnium (Hf), and mixtures thereof, wherein the cerium oxide is present in greater amounts than the trivalent dopant. and (ii) a blend composition comprising a particulate composition, wherein the trivalent dopant to Ce is present in an amount less than the amount of the trivalent dopant to Ce at about 0 nm to about 3.5 nm from the surface of the particulate composition, and the average ratio of the trivalent dopant to Ce at about 15 nm from the surface of the particulate composition is greater than the ratio of the trivalent dopant to Ce at about 15 nm from the surface of the particulate composition; (ii) contacting a gaseous stream with the blend composition and removing biological contaminants by contact with the blend composition to provide a treated gaseous stream, wherein the biological contaminants are selected from the group consisting of bacteria, viruses, fungi (e.g., molds), protozoa (e.g., amoebas), and mixtures thereof. The blend compositions and particulate oxide compositions used in these methods include all of the embodiments described above. These methods may further include monitoring the biological contaminant after contact. Monitoring may be by sampling or may be continuous. In certain embodiments, the method may further include setting a target concentration of the biological contaminant and monitoring the treated gaseous stream for the biological contaminant. The target concentration may be a specified amount or detection limit.

[0174] When the biological contaminant is a bacteria or fungus / mold, removal can be expressed as a % reduction determined by using colony forming units (CFU). In these embodiments, the concentration of the bacterial contaminant after contact with the blend composition or a support composition or article containing the blend composition is between about 45 colony forming units CFU / ml and 5 x 10 5 CFU / ml.

[0175] When the biological contaminants are bacteria and / or viruses, removal can be expressed as a % reduction determined by using the most probable number (MPN) technique, which is used to estimate the concentration of viable microorganisms in a sample by replicating liquid broth growth at 10-fold dilutions.

[0176] The target concentration of the biological contaminant can also be set as a percent reduction of the contaminant from before the method and after contact in the method. In certain embodiments, the percent reduction can be from about 75% to about 100% less. In other embodiments, the percent reduction can be from about 80% to about 99.9%.

[0177] The target concentration of a biological contaminant can be set at the detection limit for that contaminant. In embodiments that include setting a target concentration for a biological contaminant, as described above, the method may further include one or more of the following additional steps: identifying the biological contaminant of interest, setting a target concentration, and monitoring the biological contaminant after the contacting step to determine or verify that the biological contaminant is below the target concentration. Depending on the biological contaminant, the target concentration may be any detectable amount of that contaminant, and the methods disclosed herein are effective for treating aqueous or gaseous streams as long as no amount of that contaminant is detected in the treated stream.

[0178] In certain of these embodiments, the stream being treated may be an aqueous stream, and the target contaminant may be a bacterium, a virus, or a protozoan (e.g., an amoeba). For example, the stream being treated may be an aqueous or gaseous stream, and the target contaminant may be E. coli, poliovirus, coronavirus, Naegleria fowleri, paramyxovirus, Mycobacterium tuberculosis, Legionella pneumophila, coronavirus, or a mixture thereof. In certain embodiments, the stream being treated is an aqueous stream, and the target contaminant is E. coli, poliovirus, Naegleria fowleri, Legionella pneumophila, coronavirus, or a mixture thereof. In certain embodiments, the stream being treated is a gaseous stream and the target contaminant is a paramyxovirus, Mycobacterium tuberculosis, a coronavirus, or a mixture thereof. In certain embodiments, the target viruses are primarily transmitted by contact and include varicella-zoster virus (VZV), variola viruses (including smallpox and monkeypox).

[0179] These particular methods include the steps of: (i) providing a blend composition comprising: (a) a silver-zinc zeolite; and (b) a particulate oxide composition comprising cerium oxide; a trivalent dopant selected from the group consisting of yttrium (Y), lanthanum (La), neodymium (Nd), praseodymium (Pr), and mixtures thereof; and optionally, an additional metal oxide selected from the group consisting of aluminum (Al), titanium (Ti), zirconium (Zr), hafnium (Hf), and mixtures thereof, wherein the cerium oxide is present in an amount greater than the trivalent dopant, and wherein an average ratio of trivalent dopant to Ce from about 0 nm to about 3.5 nm from the surface of the particulate composition is greater than a ratio of trivalent dopant to Ce from about 15 nm from the surface of the particulate composition; and (ii) providing a blend composition comprising: (a) a silver-zinc zeolite; and (b) a particulate oxide composition comprising: cerium oxide; a trivalent dopant selected from the group consisting of yttrium (Y), lanthanum (La), neodymium (Nd), praseodymium (Pr), and mixtures thereof; and optionally, an additional metal oxide selected from the group consisting of aluminum (Al), titanium (Ti), zirconium (Zr), hafnium (Hf), and mixtures thereof; wherein the cerium oxide is present in an amount greater than the trivalent dopant, and wherein an average ratio of trivalent dopant to Ce from about 0 nm to about 3.5 nm from the surface of the particulate composition is greater than a ratio of trivalent dopant to Ce from about 15 nm from the surface of the particulate composition; (iii) contacting the gaseous or aqueous stream with the blended composition and removing the biological contaminant by contact with the blended composition to provide a treated stream; and (iv) monitoring the treated stream for the biological contaminant. The target concentration can be set at a fixed amount of the contaminant or can be set at a detection limit. The method may also include identifying the contaminant of interest prior to setting the target concentration.

[0180] The blend composition and particulate oxide composition used in this method include all of the embodiments described above. The blend composition of step (i) may also be provided as part of a support composition, thus further comprising a support material comprising an organic polymer, cotton, glass fiber, or a mixture thereof, or as part of an article comprising the support composition.

[0181] Examples of gaseous feeds that can be treated according to the methods disclosed herein include, among others, building ventilation systems, aircraft or vehicle ventilation systems, and ambient indoor air. Examples of liquid feeds that can be treated according to the methods disclosed herein include, among others, tap water, well water, surface water such as water from lakes and wetlands, water for recreational activities, agricultural water, wastewater from industrial processes, and geothermal fluids. Examples of other applications involving physical contact with biological contaminants that are not filters include plastics for containers or plastics incorporated into high-touch surfaces, such as elevator buttons, escalator rail covers, stair rail covers, touchpads for electronic transactions, doors, doorknobs, etc. These high-touch surfaces can also include glass or a mixture of glass and plastic.

[0182] The blended compositions can remove bacteria, viruses, protozoa (e.g., amoeba), fungi (e.g., mold), and other microbial contaminants, and in some embodiments, can remove bacteria, viruses, protozoa (e.g., amoeba), fungi (e.g., mold), and mixtures thereof from gas or liquid feeds.

[0183] In one embodiment, this process is contemplated for removing biological contaminants from gaseous or aqueous streams using a blended composition comprising a silver-zinc zeolite and a particulate oxide composition. The gaseous stream may be one or more of an ambient air supply or multiple air supplies for a ventilation system that contain or may contain undesirable amounts of biological and / or other contaminants. The aqueous stream may be one or more of drinking water and groundwater supplies that contain or may contain undesirable amounts of biological and / or other contaminants. Additionally, aqueous streams may include, but are not limited to, well water, surface water (including natural and artificial waters and waters for recreational purposes, such as water from lakes, ponds, and wetlands), agricultural water, wastewater from industrial processes, and geothermal water.

[0184] In some embodiments, the biological contaminant-containing gaseous stream passes through an inlet into a vessel at a temperature and pressure, typically ambient temperature and pressure, such that the gases in the biological contaminant-containing gaseous stream remain in a gaseous state. Within the vessel, the biological contaminant-containing gaseous stream is contacted with a blended composition. Contact between the blended composition and the biological contaminant-containing gaseous stream removes the biological contaminants. Contact between the blended composition and the biological contaminant-containing gaseous stream removes a measurable amount of the biological contaminants, and in some embodiments, at least 90%, more preferably 95%, and even more preferably 99% or 99%+ of the biological contaminants. The blended compositions and particulate oxide compositions used in these methods include all of the embodiments described above.

[0185] In some embodiments, the biological contaminant-containing aqueous stream passes through an inlet into a vessel at a temperature and pressure, typically ambient temperature and pressure, such that the water in the biological contaminant-containing aqueous stream remains in a liquid state. Within the vessel, the biological contaminant-containing aqueous stream is contacted with a blended composition. Contact of the blended composition with the biological contaminant-containing aqueous stream removes a measurable amount of the biological contaminants, and in some embodiments, at least 90%, more preferably 95%, and even more preferably 99% or 99%+ of the biological contaminants. The blended compositions and particulate oxide compositions used in these methods include all of the embodiments described above.

[0186] In some embodiments, the blended composition is in the form of a fixed bed. Furthermore, the fixed bed containing the blended composition typically comprises particles containing trivalent-doped cerium oxide and particles of silver-zinc zeolite. The blended composition may have a shape and / or configuration that exposes a maximum trivalent-doped cerium oxide particle surface area to the gaseous or aqueous fluid with minimal backpressure and flow rate of the gaseous or aqueous fluid through the fixed bed. If desired, the blended composition may be in the form of a shaped body, such as beads, extrudates, porous polymer structures, or monoliths. The blended composition may be supported as a layer and / or coating on such bead, extrudate, porous polymer structure, or monolith support.

[0187] Contact of the blend composition with the biological contaminant-containing fluid is typically carried out at a temperature of from about 1° C. to about 100° C., more typically from about 5° C. to about 40° C. Additionally, contact of the blend composition with the biological contaminant-containing aqueous stream is typically carried out at a pH of from about pH 1 to about pH 11, more typically from about pH 3 to about pH 9. Contact of the blend composition with the biological contaminant-containing fluid is typically carried out for a period of more than about 30 seconds and up to about 24 hours.

[0188] In general, the blended composition may be used to treat any biological contaminant, particularly bacteria, viruses, protozoa (eg, amoeba), fungi, yeast, and mixtures thereof.

[0189] Contacting a blended composition with a gaseous or aqueous stream containing biological contaminants can effectively reduce the level of the biological contaminant in the gaseous or aqueous stream. Typically, contacting a blended composition with a biological contaminant can reduce its concentration by more than about 75%. More typically, contacting a blended composition with a biological contaminant can reduce its concentration by more than about 80%, more typically by more than about 85%, more typically by more than about 90%, more typically by more than about 95%, more typically by more than about 97.5%, more typically by more than about 99%, and even more typically by more than about 99.5%. If the biological contaminant is a bacterium or mold, the percent reduction can be determined by count using colony-forming units (CFUs). If the biological contaminant is a bacterium or virus, the percent reduction can be determined by most probable number (MPN).

[0190] A method of treating air or water to remove biological contaminants includes passing an air or water stream containing a first concentration of one or more undesirable biological contaminants through a material, article, or support composition comprising a blend composition, and obtaining a treated air or water stream having a concentration of the one or more undesirable biological contaminants that is less than the first concentration.

[0191] In certain embodiments, the biological contaminant to be removed is a virus. After contact with an article or support composition comprising the blend composition, the concentration of the virus can be at or below a target concentration of the virus. When treating air or a gaseous stream, the contacted (or treated) stream has a virus concentration at or below the target concentration of the virus. In particular in these embodiments, the virus is a coronavirus.

[0192] In certain embodiments, the biological contaminant being removed is bacteria. After contact with an article or support composition comprising the blend composition, the concentration of bacteria can be at or below a target concentration of bacteria. When treating air or a gaseous stream, the contacted (or treated) stream has a bacterial concentration at or below the target concentration of bacteria. In a refinement of these embodiments, the bacteria is fecal coliform bacteria.

[0193] In certain embodiments, the biological contaminants to be removed are protozoa (e.g., amoebas). After contact with an article or support composition containing the blend composition, the concentration of protozoa (e.g., amoebas) can be at or below a target concentration of protozoa (e.g., amoebas). When treating air or a gaseous stream, the contacted (or treated) stream has a protozoa (e.g., amoebas) concentration at or below a target concentration of protozoa (e.g., amoebas). In particular in these embodiments, the protozoa (e.g., amoebas) to be removed are Naegleria fowleri and / or Cryptosporidium.

[0194] In certain embodiments, the biological contaminant being removed is a fungus (e.g., mold). After contact with an article or support composition comprising the blend composition, the concentration of the fungus can be at or below a target concentration of the fungus. When treating air or a gaseous stream, the contacted (or treated) stream has a fungus concentration at or below a target concentration of the fungus. In particular in these embodiments, the fungus being removed is Trichophyton mentagrophytes and / or Aspergillus.

[0195] The concentration of contaminants after contact with a support composition or material or article containing the blend composition is between about 45 colony forming units CFU / ml and 5 x 10 5 The target concentration can be set at a certain amount of contaminant (e.g., virus, bacteria, amoeba, fungus) CFU per ml, or can be set at the limit of detection.

[0196] In some embodiments, the blended composition itself is slurried with the biological contaminant-containing aqueous stream. It can be understood that the blended composition of silver-zinc zeolite and the particulate oxide composition contacts the biological contaminant-containing aqueous stream when slurried. Without wishing to be bound by any theory, it is believed that by slurrying and / or contacting the blended composition comprising the trivalent-doped cerium oxide particulate composition and silver-zinc zeolite with the biological contaminant-containing aqueous stream, some, if not most or all, of the biological contaminants contained in the biological contaminant-containing aqueous stream are removed from the biological contaminant-containing aqueous stream. After the blended composition is slurried and / or contacted with the biological contaminant-containing aqueous stream, the slurry is filtered by any known solid-liquid separation method. The blended composition and particulate oxide composition utilized in the method involving slurrying include all of the above-described embodiments. [Example]

[0197] The following examples are provided to more fully illustrate the particulate oxide compositions and methods, but are in no way intended to limit the scope of the invention.

[0198] Scanning electron microscope (SEM) images were collected using an FEG Zeiss Ultra 55 (1 nm resolution). Transmission electron microscope (TEM) images were collected using an FEI Titan Themis 200 (0.09 nm resolution). Surface area, pore radius, and pore volume were measured using the BET / BJH method (ASTM D3663-20). Hg porosity and total Hg pore volume were measured using a Micromeritics Autopore IV 9500 system. The procedure outlined in ASTM International test method D 4284-07 was followed. Particle size was measured using a Microtrac S3500. X-ray diffraction was performed using a Bruker D2 Phaser X-ray diffractometer. Peak half-width was used to determine crystallite size. Zeta potential versus pH was measured using a Malvern Panalytical (Zetaziser Nano ZS) ZEN3600 using a procedure similar to ASTM E2865-12 (2018). As will be understood, crystallite size is the size of an individual crystal as measured by XRD or TEM. xxSize is the size of particles made from individual crystallites and measured by laser diffraction. Temperature-programmed desorption of CO2 was performed as described in Hakim, A. et al., "Temperature Programmed Desorption of Carbon Dioxide for Activated Carbon Supported Nickel Oxide: The Adsorption and Desorption Studies," Advanced Materials Research, Vol. 1087 (2015), pp. 45-49. Temperature-programmed reduction with hydrogen was performed as described in Hurst, NW et al., "Temperature Programmed Reduction," Catalysis Reviews Science and Engineering, 24:2, 233-309. Depth profilometry was performed as described in Noel, C. et al., "ToF-SIMS Depth Profiling of Organic Delta Layers with Low-Energy Cesium Ions: Depth Resolution Assessment," Journal of the American Society for Mass Spectrometry, Vol. 30 (2019), pp. 1537-1544.

[0199] Example 1 A trivalent-doped cerium oxide composition was prepared by the following method: 68 g (0.297 mol) of lanthanum carbonate and 464 g (2.7 mol) of cerium oxide were mixed with 200 ml of a 1.0 mol / L lanthanum nitrate solution. The components were mixed for 2 hours. The mixture was then heated in a furnace to 550°C for 2 hours, yielding 542 g of a mixed cerium-lanthanum oxide, which was approximately 15% lanthanum oxide by weight. This may also be referred to as La-doped cerium oxide.

[0200] Scanning electron microscope (SEM) images of a sample of the composition of Example 1 were collected and are displayed in Figures 1 and 2. The images show a porous material that is somewhat spherical in shape. Transmission electron microscope (TEM) images of a sample of the composition of Example 1 were collected and are displayed in Figures 3 and 4. The images reveal clusters of spheres. The surface area, pore radius, and pore volume of a sample of the composition of Example 1 were analyzed and found to be 98.332 m 2 / g(BET) and 135.268m 2 The pore radius was found to be 3.235 nm and the pore volume was found to be 0.248 cc / g (BJH). The measured Hg porosity was determined to be 0.21 cc / g, with pores <1 μm at 0.46 cc / g, for a total pore volume of 0.96 cc / g. The particle size distribution was measured as described above, with a D10 of 3.552 μm, a D50 of 12.1 μm, and a D90 of 43.12 μm. The crystallite size measured by XRD was determined to be 9.77 nm. The temperature-programmed desorption profile is shown in Figure 5A. The desorption of CO2 had three peak temperatures at 172 °C, 350 °C, and 735 °C, indicating both physisorption and chemisorption of CO2. The H2TPR is shown in Figure 6 and shows a strong peak near 500 °C, in contrast to Examples 2 and 3, which have broader peaks. The zeta potential as a function of pH is shown in Figure 7. The isoelectric point (IEP) was 8.1. LaO as a function of depth + versus 140 Chief Operating Officer + The ratio of LaO is plotted in Figure 8. + vs. CeO + Note that the ratio of is higher at shallower depths and approaches a constant level as depth increases. This indicates that the concentration of La is higher at and near the surface for the material of Example 1. The material of Example 1 is an embodiment of trivalent-doped cerium oxide with a unique depth profile.

[0201] Example 2 A trivalent-doped cerium oxide composition was prepared by the following method, also described in U.S. Patent Application No. 17 / 870,068: 129 ml of a 1 mol / L Ce(NO3)4 solution was mixed with 24 ml of a 1 mol / L La(NO3)3 solution. The resulting solution was heated to reflux for at least 2 hours. 5.5 mol / L NH4OH was then added to a pH of 10. The resulting solid was filtered and washed with DI water until the rinse water had a pH of <15 mS / cm. The resulting powder was heated in an air furnace at 550°C for at least 2 hours to yield a mixed cerium-lanthanum oxide with approximately 15% lanthanum oxide by weight, which may also be referred to as La-doped cerium oxide.

[0202] Figures 10 and 11 are SEM images. The images show the porous material as being somewhat spherical in shape. Figures 12A-12D contain TEM images. Clusters of spheres are evident in the images, and diffraction planes can be seen. The surface area is 120.464 m 2 / g(BET) and 143.087m 2 The pore radius was found to be 3.245 nm and the pore volume was found to be 0.285 cc / g (BJH). The pore volume for pores <0.1 μm was measured to be 0.23 cc / g, and the pore volume for pores <1 μm was 0.45 cc / g, for a total pore volume of 0.99 cc / g. The particle size distribution was measured as described above, with a D10 of 1.301 μm, a D50 of 5.545 μm, and a D90 of 13.109 μm. The crystallite size measured by XRD was determined to be 9.03 nm. The temperature-programmed desorption profile is shown in Figure 5B. CO2 desorption has a single peak temperature at 175 °C, indicating only CO2 physisorption. Any peaks at higher temperatures are not distinguishable from the background, and therefore CO2 chemisorption is not detected. The H2TPR is shown in Figure 6 and shows a broad peak near 566 °C. The zeta potential as a function of pH is shown in Figure 7. The isoelectric point (IEP) was 7.34.

[0203] LaO as a function of depth + versus 140 Chief Operating Officer + The ratio of LaO is plotted in Figure 8. This material exhibits a nearly constant LaO+ vs. CeO + Note that the ratio of La to La indicates that the concentration is approximately the same at the surface as it is at depth.

[0204] Example 3 A cerium(IV) oxide composition was prepared by the following method: In a sealed, stirred vessel, one liter of 0.12 M ammonium cerium(IV) nitrate solution was prepared from ammonium cerium(IV) nitrate crystals dissolved in nitric acid and held at approximately 90°C for approximately 24 hours. In a separate vessel, 200 ml of 3 M ammonium hydroxide solution was prepared and held at room temperature. The two solutions were then combined and stirred for approximately 1 hour. The resulting precipitate was filtered using a Buchner funnel equipped with filter paper. The solid was then thoroughly washed in the Buchner using deionized water. Following the washing / filtration step, the wet hydrate was calcined in a muffle furnace at approximately 450°C for 3 hours to form the cerium(IV) oxide composition.

[0205] The surface area is 126m 2 / g(BET) and 167m 2 The pore volume was found to be 0.309 cc / g (BJH), with a pore radius of 3.62 nm. The pore volume for pores <0.1 μm was measured to be 0.24 cc / g, and the pore volume for pores <1 μm was 0.35 cc / g, for a total pore volume of 0.85 cc / g. The particle size distribution was measured as described above, with a D10 of 2 μm, a D50 of 9 μm, and a D90 of 25 μm. The crystallite size measured by XRD was determined to be 8.43 nm. The temperature-programmed desorption profile is shown in Figure 5C. CO2 desorption has a single peak temperature at 175 °C, indicating only CO2 physisorption. Any peaks at higher temperatures are not distinguishable from the background, and therefore CO2 chemisorption is not detected. The HTPR is shown in Figure 6 and shows broad peaks near 500 and 900 °C. The zeta potential as a function of pH is shown in Figure 7. The isoelectric point (IEP) was 7.22.

[0206] Depth profilometry was not performed because Ce was the only component in this sample, and this sample contained no trivalent dopants.

[0207] Example 4 A trivalent-doped cerium oxide composition was prepared by the following method. In a sealed, stirred vessel, one liter of 0.12 M ammonium cerium(IV) nitrate solution was prepared from ammonium cerium(IV) nitrate crystals dissolved in nitric acid. To this, 199.5 g (0.5 mol) of commercially available Al(NO3)3 was added and maintained at approximately 90°C for approximately 24 hours. In a separate vessel, 200 ml of 3 M ammonium hydroxide solution was prepared and maintained at room temperature. The two solutions were then combined and stirred for approximately 1 hour. The resulting precipitate was filtered using a Buchner funnel equipped with filter paper. The solid was then thoroughly washed in the Buchner funnel using deionized water. Following the washing / filtration step, the wet hydrate was calcined in a muffle furnace at approximately 450°C for 3 hours to form an aluminum cerium(IV) oxide composition. This oxide was suspended in a praseodymium nitrate solution containing praseodymium carbonate. The ratio of Pr to aluminum cerium (IV) oxide was varied to achieve 4%, 8%, 12%, or 20% loading of Pr oxide in the final product. The components were mixed for 2 hours. The mixture was then heated in a furnace at 550°C for 2 hours to obtain mixed cerium aluminum praseodymium oxide, which may also be referred to as Pr-doped cerium oxide.

[0208] The depth profile of each of these materials was then measured, and the PrO versus depth + versus 140 Chief Operating Officer + The ratio of PrO is shown in Figure 9. As in Example 1, the trivalent PrO + of 140 Chief Operating Officer + The ratio to is higher at the surface and at shallow depths and approaches a constant level with increasing depth. The material of Example 4 is an embodiment of trivalent doped cerium oxide with a unique depth profile.

[0209] Example 5 A praseodymium-doped cerium oxide composition was prepared by the following method, similar to that of Example 2. 129 ml of a 1 mol / L Ce(NO3)4 solution was mixed with 82 ml of a 1 mol / L Pr(NO3)3 solution and 63.9 g (0.3 mol) of commercially available Al(NO3)3. The resulting solution was heated to reflux for at least 2 hours. 5.5 mol / L NH4OH was then added to a pH of 10. The resulting solid was filtered and washed with DI water until the wash water had a pH of <15 mS / cm. The resulting powder was heated in an air furnace at 550°C for at least 2 hours to obtain a mixed cerium aluminum praseodymium oxide containing approximately 16% Pr oxide by weight. This may also be referred to as Pr-doped cerium oxide.

[0210] Depth profiles were measured and the data are shown in Figure 9. As in Example 2, 140 Chief Operating Officer + trivalent to PrO + The ratio of Pr to Pr is almost constant from the surface to the maximum measured depth, indicating that the Pr concentration is almost the same at the surface as at the depth.

[0211] The depth profile data from Examples 1, 2, 4, and 5 were then analyzed to determine the trivalent to Ce ratio (LaO + / CeO + or PrO + / CeO + ) were compared. This average was then compared to the same ratio at a depth of 15 nm. The % increase was then calculated as ((average of 0-3.5 nm) - (ratio at 15 nm)) / (ratio at 15 nm) x 100. [Table 1]

[0212] Example 6 A commercially available inorganic antimicrobial agent was obtained from a supplier (Surfatas) under the trade name Life DJ / AM-00-1A (CAS No. 130328-20-0). Product literature describes this material as having a 2.5% silver content and a 10-16% zinc content. The remainder of the material is zeolite. It is registered with the EPA as a pesticide under EPA registration number 71227-1-85576. Alternatively, this material can be produced by the method described in Iyigundogdu et al., "Development of durable antimicrobial surfaces containing silver- and zinc-ion-exchanged zeolites," Turkish Journal of Biology, Vol. 38: No. 3, Article 14, (2014) pp. 420-427. Briefly, the method involves the hydrothermal synthesis of zeolite, followed by ion exchange of the sodium (Na) contained in the zeolite with silver (Ag) and zinc (Zn) by treatment with solutions of AgNO3 and ZnCl2, respectively.

[0213] Example 7A To make the blended powder, a measured amount of the composition of Example 1 was placed in a container along with a measured amount of the material from Example 6. In this example, 9 g of Example 1 was placed in a 60 ml polyethylene bottle. Then, 1 g of Example 6 was added. Thus, the mixture was 90% Example 1 and 10% Example 6. The bottle was sealed and placed in a tumbler that rotated the bottle, inverting it every second. The bottle was rotated in this manner for at least 1 hour. The resulting mixture was used without further processing. No chemical reactions were expected. The materials were simply blended together as dry powders. The blended powder was characterized by measuring the BET surface area and pore radius. The BHJ surface area and pore volume are not reported because the BHJ method is not valid for zeolites, which makes pore volume meaningless. The results are summarized in Table 2.

[0214] Example 7B The material of Example 7B was prepared and characterized similarly to Example 7A, except that 7.5 g of Example 1 and 2.5 g of Example 6 were used to give a mixture of 75% Example 1 and 25% Example 6.

[0215] Example 7C The material of Example 7C was prepared and characterized similarly to Example 7A, except that 5.0 g of Example 1 and 5.0 g of Example 6 were used to obtain a mixture of 50% Example 1 and 50% Example 6. The particle size distributions D50, D90, and D100 were also measured for this blend, and the results are summarized in Table 2.

[0216] Example 7D The material of Example 7D was prepared and characterized similarly to Example 7A, except that 2.5 g of Example 1 and 7.5 g of Example 6 were used to give a mixture of 25% Example 1 and 75% Example 6.

[0217] Example 8A To make the blended powder, a measured amount of the composition of Example 3 was placed in a container along with a measured amount of the material from Example 6. In this example, 9 g of Example 3 was placed in a 60 ml polyethylene bottle. 1 g of Example 6 was then added. Thus, the mixture was 90% Example 3 and 10% Example 6. The bottle was sealed and placed in a tumbler that rotated the bottle, inverting it every second. The bottle was rotated in this manner for at least 1 hour. The resulting mixture was used without further processing. No chemical reactions were expected. The materials were simply blended together as dry powders. The blended powder was characterized by measuring the BET surface area, pore radius, and pore volume. The results are summarized in Table 2.

[0218] Example 8B The material of Example 8B was prepared and characterized similarly to Example 8A, except that 7.5 g of Example 3 and 2.5 g of Example 6 were used to give a mixture of 75% Example 3 and 25% Example 6.

[0219] Example 8C The material of Example 8C was prepared and characterized similarly to Example 8A, except that 5.0 g of Example 3 and 5.0 g of Example 6 were used to give a mixture of 50% Example 3 and 50% Example 6.

[0220] Example 8D The material of Example 8D was prepared and characterized similarly to Example 8A, except that 2.5 g of Example 3 and 7.5 g of Example 6 were used to give a mixture of 25% Example 3 and 75% Example 6. [Table 2] The trends in BET SA and pore radius between these blended powders confirm that they are simply physical mixtures. Furthermore, the D50, D90, and D100 values ​​for Example 1, Blend Example 7C, and Example 6 also confirm that they are physical mixtures. A physical mixture of two powders would be expected to have the BET SA, pore radius, and PSD of the unblended powders. Here, it is observed that as the proportion of Example 6 material increases, the measured BET SA and pore radius approach those of Example 6.

[0221] Example 9 The bacterial removal properties of the compositions of Examples 1, 3, 6, 7A-D, and 8B-C were tested using an adapted EN 13727 method. A 4 ml suspension of these materials (0.2 g / ml in deionized water) was added to a mixture of 0.5 ml of methicillin-resistant Staphylococcus aureus (MRSA) ATCC® 43300™ suspension and 0.5 ml of hard water at room temperature (20 ± 1°C). At 1 hour, 0.5 mL of the mixture was transferred to a tube containing 4 mL of neutralizing agent (Dey Engley broth) and incubated at 20 ± 1°C for 5 minutes ± 10 seconds. Then, 0.5 mL of the challenge suspension was added to each neutralizing tube, mixed, and incubated at 20 ± 1°C for 30 minutes ± 1 minute. The suspensions were inoculated into TSA and evaluated for efficacy and toxicity. The results are shown in Table 3 and Figure 13. These results show that the blended materials of 7A-D removed more bacteria than the unblended materials of Examples 1 and 6. In comparison, the blended materials of 8B-C do not show an increase in bacterial removal over the unblended materials of Examples 3 and 6. [Table 3]

[0222] Example 10 The material of Example 7A is suspended in deionized water, and a binder such as citric acid is added to the water. A substrate such as cotton fabric is then dipped into the suspension at least once. The substrate is removed and then dried. The resulting fabric has a coating of the composition of Example 7A on its surface. The coated fabric is then placed in a funnel so that the fabric remains in the funnel as water passes through. Water contaminated with E. coli is then poured into the funnel and allowed to come into contact with the coated fabric. The water collected from the funnel is analyzed and found to have a reduced concentration of E. coli.

[0223] Example 11 The material of Example 7A is suspended in deionized water, and a binder such as citric acid is added to the water. A substrate such as cotton fabric is then dipped into the suspension at least once. The substrate is removed and then dried. The resulting fabric has a coating of the composition of Example 1 on its surface. The coated fabric is then placed on an air filter, covering the surface of the air filter and allowing air to pass through the fabric. The filter is then placed in an HVAC or indoor air filtration unit. When the device is turned on, coronavirus-contaminated air passes through the filter. The air exhausted from the unit is analyzed, revealing a reduction in coronavirus concentration.

[0224] Example 12 Polyethylene granules or powder are mechanically mixed with the material of Example 7A at approximately 1% by weight of the material of Example 7A. The mixture is then fed into a heating chamber to form an end-use product, such as a bottle. After bottles are formed from the polyethylene-containing material of Example 7A, the surface is tested for antimicrobial or bacteriostatic properties against the polyethylene by exposing the surface to E. coli. The surface is then analyzed for E. coli and found to have fewer colony-forming units than the control. Another test is performed by placing pasteurized milk in the formed bottles and observing the time required for the milk to spoil. Compared to polyethylene bottles not containing the material of Example 7A, the milk takes longer to spoil.

[0225] Unless otherwise indicated, all numbers expressing quantities of ingredients, properties such as molecular weight, reaction conditions, and the like used in the specification and claims are to be understood as being modified in all instances by the term "about." Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and appended claims are approximations that may vary depending upon the desired properties sought to be obtained.

[0226] Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the technology are approximations, the numerical values ​​set forth in the specific examples are reported as precisely as possible. However, any numerical value inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements.

[0227] It will be apparent that the compositions and methods described herein are well adapted to attain the objects and advantages mentioned, as well as those inherent therein. Those skilled in the art will recognize that the methods and systems herein can be implemented in numerous ways and, thus, are not limited by the illustrative embodiments and examples set forth above. In this regard, any number of the features of different embodiments described herein may be combined into one single embodiment, and alternative embodiments may include fewer or more than all of the features described herein.

[0228] While various embodiments have been described for purposes of this disclosure, various changes and modifications can be made that are within the scope fully contemplated by this disclosure. Numerous other variations may be made that are encompassed by the spirit of this disclosure, as will be readily apparent to those skilled in the art.

Claims

1. (a) less than about 50% to about 1% by weight of a silver-zinc zeolite; and (b) greater than about 50% to 99% by weight of a particulate oxide composition, cerium oxide, a trivalent dopant selected from the group consisting of yttrium (Y), lanthanum (La), neodymium (Nd), praseodymium (Pr), and mixtures thereof; and optionally comprising a particulate oxide composition comprising an additional metal oxide selected from the group consisting of aluminum (Al), titanium (Ti), zirconium (Zr), hafnium (Hf), and mixtures thereof; the cerium oxide is present in an amount greater than the trivalent dopant, and the average ratio of trivalent dopant to Ce from about 0 nm to about 3.5 nm from the surface of the particulate oxide composition is greater than the ratio of trivalent dopant to Ce at about 15 nm from the surface of the particulate composition; Blended compositions for biological contaminant removal.

2. 2. The blend composition of claim 1, wherein the silver-zinc zeolite is a silver and zinc ion surface-modified Linde Type A (LTA) zeolite.

3. The particulate oxide composition cerium oxide in an amount of about 99.9 wt. % to about 20 wt. %, based on the total weight of the particulate oxide composition; a trivalent dopant in an amount of from about 0.1 wt. % to about 50 wt. % based on the total weight of the particulate oxide composition; and 3. The blend composition of claim 1 or 2, comprising an additional metal oxide in an amount of about 70 wt. % to about 0 wt. %, based on the total weight of the particulate oxide composition.

4. (a) about 35% to about 5% by weight of a silver-zinc zeolite; and (b) comprising about 65% to about 95% by weight of a particulate oxide composition; The blend composition of any one of claims 1 to 3.

5. The particulate oxide composition cerium oxide in an amount of about 99.9 wt. % to about 50 wt. %, based on the total weight of the particulate oxide composition; and 5. The blend composition of any one of claims 1 to 4, comprising a trivalent dopant in an amount of from about 0.1 wt% to about 50 wt%, based on the total weight of the particulate oxide composition.

6. The particulate oxide composition cerium oxide in an amount of about 20% to about 30% by weight based on the total weight of the particulate oxide composition; a trivalent dopant in an amount of from about 2 wt. % to about 25 wt. % based on the total weight of the particulate oxide composition; and 5. The blend composition of claim 1, 2 or 4, comprising an additional metal oxide in an amount of about 45 wt% to about 78 wt%, based on the total weight of the particulate oxide composition.

7. The particulate oxide composition cerium oxide in an amount of about 45 wt. % to about 78 wt. % based on the total weight of the particulate oxide composition; a trivalent dopant in an amount of from about 2 wt. % to about 25 wt. % based on the total weight of the particulate oxide composition; and 5. The blend composition of claim 1, 2 or 4, comprising an additional metal oxide in an amount of about 20 wt% to about 30 wt%, based on the total weight of the particulate oxide composition.

8. 8. The blend composition of claim 1, wherein the particulate oxide composition has an average ratio of trivalent dopant to Ce from about 0 nm to about 3.5 nm from the surface of the particulate oxide composition that is from about 10% to about 250% greater than the ratio of trivalent dopant to Ce from about 15 nm from the surface of the particulate oxide composition.

9. 9. The blend composition of claim 8, wherein the particulate oxide composition has an average ratio of trivalent dopant to Ce from about 0 nm to about 3.5 nm from the surface of the particulate oxide composition that is from about 15% to about 250% greater than the ratio of trivalent dopant to Ce from about 15 nm from the surface of the particulate oxide composition.

10. 6. The blend composition of any one of claims 1 to 5, wherein the particulate oxide composition comprises from about 2% to about 30% by weight of a trivalent dopant.

11. (a) about 25% to about 10% by weight of a silver-zinc zeolite; and (b) about 75% to about 90% by weight of a particulate oxide composition; The blend composition of any one of claims 1 to 10.

12. A support material comprising an organic polymer, cotton, glass fiber, or a mixture thereof, and the blend composition for biological contaminant removal according to claim 1.

1. A support composition for removing biological contaminants, comprising: The blend composition for biological contaminant removal is deposited on or within the support material. Support composition.

13. 13. The support composition of claim 12, wherein the support material is an organic polymer selected from the group consisting of polyethylene, polyvinyl chloride, nylon, polypropylene, polyester, polyurethane, polyamide, polyolefin, polycarbonate, copolymers thereof, and mixtures thereof.

14. The support composition of claim 12 wherein the support material is cotton.

15. 13. The support composition of claim 12, wherein the composition for biological decontamination comprises from about 0.5 to about 80 weight percent, based on the total weight of the support composition.

16. 13. The support composition of claim 12, which is a filter material or a plastic.

17. Providing the blend composition of claim 1; contacting the blended composition with a biological contaminant selected from the group consisting of bacteria, viruses, protozoa, fungi, and mixtures thereof; and removing at least about 90% of the biological contaminants by contact with the blend composition. Methods for removing biological contaminants.

18. 18. The method of claim 17, wherein the blend composition is contained within a filter material or a plastic.

19. 20. The method of claim 17, wherein the blend composition for biological contaminant removal is deposited on or within a support material comprising an organic polymer, cotton, fiberglass, or a mixture thereof.

20. 20. The method of any one of claims 17 to 19, wherein the blended composition for removing biological contaminants removes approximately 99% or more of the biological contaminants.

21. A method according to any one of claims 17 to 20, wherein the biological contaminant is in an aqueous stream or a gaseous stream or a mixture thereof.

22. The method of any one of claims 17 to 20, wherein the contacting is by solid touching an article comprising the blend composition for biological decontamination.

23. 21. The method of claim 17 or 20, further comprising the steps of setting a target concentration of the biological contaminant and monitoring the biological contaminant after contacting.

24. A plastic article comprising: (a) a support composition for removing biological contaminants comprising an organic polymer selected from the group consisting of polyethylene, polyvinyl chloride, nylon, polypropylene, polyester, polyurethane, polyamide, polyolefin, polycarbonate, copolymers thereof, and mixtures thereof, and the blend composition for removing biological contaminants of claim 1, wherein the blend composition is deposited on or within the organic polymer; A plastic article comprising about 50 to about 100 weight percent of said support composition, based on the total weight of said plastic article.

Images