Heterogeneous oxidation catalyst with improved selectivity

Abstract

A method of a preparing an oxidation catalyst includes contacting a first transition metal salt and a dopant with a support material to form a bimetallated support, reducing the bimetallated support by contacting the bimetallated support with a reducing agent to form a reduced bimetallated support, aging the reduced bimetallated support, contacting the aged reduced bimetallated support with a second transition metal salt to form a trimetallated support, reducing the trimetallated support by contacting the trimetallated support with a reducing agent to form a reduced trimetallated support; and aging the reduced trimetallated support to form the oxidation catalyst.

Description

HETEROGENEOUS OXIDATION CATALYST WITH IMPROVED SELECTIVITYCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims benefit and priority of U.S. provisional patent application Serial No. 63 / 684,176 filed August 16, 2024, and entitled “HETEROGENEOUS OXIDATION CATALYST WITH IMPROVED SELECTIVITY,” and also clams benefit and priority of U.S. provisional patent application Serial No. 63 / 684, 192 filed August 16, 2024, and entitled “HETEROGENEOUS OXIDATION CATALYST WITH IMPROVED SELECTIVITY,” each of which is hereby incorporated herein by reference in its entirety for all purposes.STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[0002] Not applicable.TECHNICAL FIELD

[0003] The present disclosure relates generally to catalysts. More particularly, the present disclosure relates to oxidation catalysts. Still more particularly, the present disclosure relates to novel oxidation catalysts for the production of higher value chemicals.BACKGROUND

[0004] Catalysts are essential to modern society in many fields, such as energy conversion, chemical manufacturing, and environmental remediation. It is estimated that approximately 85% of industrial chemical processes rely on catalysts. Compared to homogeneous catalysts, heterogeneous catalysts possess beneficial features such as being environmentally friendly, sustainability, simplicity and versatility of process engineering, easy recovery and reuse, less reactor and plant corrosion problems, and environmentally safe disposal.

[0005] In particular, oxidation catalysis not only play a crucial role in the current chemical industry for the production of key intermediates such as alcohols, epoxides, aldehydes, ketones and organic acids, but also contribute to the establishment of novel green and sustainable chemical processes. Some well-known highly challenging chemical reactions involve selective oxidation reactions and the aerobic oxidation of alcohols in the liquid phase which have attracted much attention in recent years because of their high significance in green chemistry or energy chemistry.

[0006] Precise control of catalytic selectivity, producing one molecule out of many other thermodynamically feasible product molecules, is a key green chemistry concept for developing clean processes. Facing the dual challenges of resource and environment, catalytic selectivity has become an important driving force for sustainable development. A catalyst usually produces more than one product, and formation of the desired molecule is often considered as important a characteristic as the overall catalyst activity. An ongoing need exists to develop active, selective and stable heterogeneous catalysts with sufficient selectivity toward a target product.BRIEF SUMMARY OF THE DISCLOSURE

[0007] Disclosed herein is a method of a preparing an oxidation catalyst comprising contacting a first transition metal salt and a dopant with a support material to form a bimetallated support; reducing the bimetallated support by contacting the bimetallated support with a reducing agent to form a reduced bimetallated support; aging the reduced bimetallated support; contacting the aged reduced bimetallated support with a second transition metal salt to form a trimetallated support; reducing the trimetallated support by contacting the trimetallated support with a reducing agent to form a reduced trimetallated support; and aging the reduced trimetallated support to form the oxidation catalyst.

[0008] Also disclosed herein is a method of selectively oxidizing glucose comprising contacting glucose with the oxidation catalyst of claim 1 in the presence of oxygen under conditions suitable for the formation of glucose oxidation products.

[0009] Also disclosed herein is a method of selectively oxidizing glucodialdose comprising contacting glucodialdose with the oxidation catalyst of claim 1 in the presence of oxygen under conditions suitable for the formation of glucose oxidation products.

[0010] Aspects described herein comprise a combination of features and characteristics intended to address various shortcomings associated with certain prior devices, systems, and methods. The foregoing has outlined rather broadly the features and technical characteristics of the disclosed aspects in order that the detailed description that follows may be better understood. The various characteristics and features described above, as well as others, will be readily apparent to those skilled in the art upon reading the following detailed description, and by referring to the accompanying drawings. It should be appreciated that the conception and the specific aspectsdisclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes as the disclosed aspects. It should also be realized that such equivalent constructions do not depart from the spirit and scope of the principles disclosed herein.BRIEF DESCRIPTION OF THE DRAWINGS

[0011] For a detailed description of various exemplary aspects, reference will now be made to the accompanying drawings in which:

[0012] Figure 1 is a bar graph depicting the amount of glucaric acid produced and percentage carbon loss for the reactions catalyzed by the indicated catalyst samples.

[0013] Figure 2 is a graph plotting the cumulative glucaric acid amount produced as a function of pass number for the reactions catalyzed by the indicated catalyst samples.

[0014] Figure 3 is a graph of the normalized values of glucaric acid amount produced as a function of pass number for the reactions catalyzed by the indicated catalyst samples.

[0015] Figure 4 is a graph of the percentage carbon loss for the oxidation of glucose by the indicated catalyst samples.

[0016] Figure 5 is a bar graph depicting the percentage conversion of the reagent glucodialdose and the selectivity for glucaric acid formation by the indicated catalyst samples.

[0017] Figure 6 is a bar graph of the amount of glucaric acid and on-path intermediates produced for a reaction catalyzed by the indicated catalyst samples.

[0018] Figure 7 is a bar graph depicting the percentage of on-path intermediates formed during the glucose oxidation reactions catalyzed by the indicated catalyst samples.

[0019] Figure 8 is a bar graph depicting the percentage carbon loss during the glucose oxidation reactions catalyzed by the indicated catalyst samples.

[0020] Figure 9 is a bar graph depicting the cumulative carbon yield of glucaric acid during the glucose oxidation reactions catalyzed by the indicated catalyst samples.

[0021] Figure 10 is a bar graph depicting the cumulative carbon produced during the glucose oxidation reactions catalyzed by the indicated catalyst samples.

[0022] Figure 11 is a scatter plot of carbon loss as a function the normalized glucaric acid throughput amount for a variety of oxidation catalysts.

[0023] Figure 12 is a bar graph depicting the amount of glucaric acid produced compared to the amount of on-path acids produced in the reactions catalyzed by the indicated catalyst samples.

[0024] Figure 13 is a bar graph depicting the dry weight percentage of glucaric acid and on-path dry acids for a plant scale oxidation reaction of glucodialdose catalyzed by the indicated catalyst samples.

[0025] Figure 14 is a bar graph depicting the cumulative glucaric acid production per gram of catalyst for a glucose oxidation reaction.

[0026] Figure 15 is a bar graph depicting the dry weight percentage of gluconic acid, glucaric acid and other on path acids produced by a glucose oxidation reaction catalyzed a reference catalyst or the indicated catalyst samples.TECHNICAL FIELD

[0027] The following discussion is directed to various exemplary aspects. However, one skilled in the art will understand that the examples disclosed herein have broad application, and that the discussion of any aspect is meant only to be exemplary of that aspect, and not intended to suggest that the scope of the disclosure, including the claims, is limited to that aspect.

[0028] Certain terms are used throughout the following description and claims to refer to particular features or components. As one skilled in the art will appreciate, different persons may refer to the same feature or component by different names. This document does not intend to distinguish between components or features that differ in name but not function. The drawing figures are not necessarily to scale. Certain features and components herein may be shown exaggerated in scale or in somewhat schematic form and some details of conventional elements may not be shown in interest of clarity and conciseness.

[0029] Unless the context dictates the contrary, all ranges set forth herein should be interpreted as being inclusive of their endpoints, and open-ended ranges should be interpreted to include only commercially practical values. In addition, with respect to all ranges disclosed herein, such ranges are intended to include any combination of the mentioned upper and lower limits even if the particular combination is not specifically listed. All lists of values should be considered as inclusive of intermediate values unless the context indicates the contrary. Where numerical ranges or limitations are expressly stated, such express ranges or limitations should be understood to include iterativeranges or limitations of like magnitude falling within the expressly stated ranges or limitations (e.g., from about 1 to about 10 includes, 2, 3, 4, etc.; greater than 0.10 includes 0.11 , 0.12, 0.13, etc.).

[0030] In the following discussion and in the claims, the terms “including” and “comprising” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to... .” As used herein, the phrases “consist(s) of’ and “consisting of” are used to refer to exclusive components of a composition, meaning only those expressly recited components are included in the composition; whereas the phrases “consist(s) essentially of’ and “consisting essentially of” are used to refer to the primary components of a composition, meaning that only small or trace amounts of components other than the expressly recited components (e.g., impurities, byproducts, etc.) may be included in the composition. For example, a composition consisting of X and Y refers to a composition that only includes X and Y, and thus, does not include any other components; and a composition consisting essentially of X and Y refers to a composition that primarily comprises X and Y, but may include small or trace amounts of components otherthan X and Y. In aspects described herein any such small or trace amounts of components otherthan those expressly recited following the phrase “consist (s) essentially of’ or “consisting essentially of’ preferably represent less than 5.0 wt.% of the composition, more preferably less than 4.0 wt.% of the composition even more preferably less than 3.0 wt.% of the composition, and still more preferably less than 1.0 wt.% of the composition. Use of broader terms such as comprises, includes, having, etc. should be understood to provide support for narrower terms such as consisting of, consisting essentially of, comprised substantially of, etc. Use of the term "optionally" with respect to any element of a claim is intended to mean that the subject element is required, or additionally or alternatively , is not required. Both alternatives are intended to be within the scope of the claim. As used herein, the terms “approximately,” “about,” “substantially,” and the like mean within 10% (i.e., plus or minus 10%) of the recited value. Thus, for example, a recited angle of “about 80 degrees” refers to an angle ranging from 72 degrees to 88 degrees.

[0031] The present disclosure relates generally to oxidation catalysts. More particularly, the present disclosure relates to heterogeneous oxidation catalysts having improved selectivity. In one or more aspects, a method of the present disclosure comprises contacting at least two metal atoms with a support material to form a composition,contacting the composition with a third metal atom to form a mixture that is further treated to form a catalyst composition having improved selectivity for a user and / or goal target product.

[0032] Product selectivity may be indicated by an increased percentage production of the target product by from about 10% to about 80%; additionally or alternatively from about 15% to about 75%; or additionally or alternatively from about 25% to about 50%. In one or more aspects, a method of the present disclosure comprises contacting at least two metal atoms with a support material to from a bimetallated composition, reducing the bimetallated composition to form a reduced composition and contacting the reduced composition with a third metal to form a trimetallated composition. Herein the catalyst compositions are characterized by an improved selectivity in product distribution or increased production of a target product and are termed oxidation catalysts with improved selectivity, designated OCIS.

[0033] In an aspect, the OCIS comprises an inorganic support material such as for example and without limitation aluminas, silicas, titanias, zirconias, aluminosilicates (e.g., clays, ceramics, and / or zeolites), spinels (e.g., zinc aluminate, zinc titanate, and / or magnesium aluminate), or combinations thereof.

[0034] In one or more aspects, the inorganic support material comprises carbon, ceramic, or metal oxides. In an aspect, the inorganic support material comprises carbon, titania (TiCk), zirconia (ZrCh) or any combination thereof which contain less than about 1 weight percent (wt.%), additionally or alternatively less than about 0.1 weight percent (wt.%) or additionally or alternatively less than about 0.01 wt.% SiC>2 binders based on the total weight of the support.

[0035] In one or more aspects, the inorganic support material is predominantly mesoporous or macroporous and substantially free from micropores. For example, the inorganic support material may comprise less than about 20% micropores, additionally or alternatively less than about 10% micropores, additionally or alternatively less than about 5% micropores, additionally or alternatively less than about 2.5% micropores, additionally or alternatively less than about 1 % micropores or additionally or alternatively less than about 0.5% micropores.

[0036] Inorganic support materials suitable for use in the present disclosure may have any suitable shape. For example, the inorganic support material may be shaped into 0.8-3 mm trilobes, quadralobes, or pellet extrudates. The inorganic support material canbe shaped by any suitable methodology such as by extrusion or tableting. For example, the inorganic support material can be shaped to facilitate utilization of the catalyst in reactors such as a fluidized moving bed or a fixed bed reaction type with or without continuous flow thereby allowing a broad flexibility regarding the adjustment of the process conditions.

[0037] An inorganic support material suitable for use in the present disclosure may have a surface area of from about 100 m2 / g to about 1000 m2 / g, additionally or alternatively from about 200 m2 / g to about 900 m2 / g; additionally or alternatively from about 250 m2 / g g to about 500 m2 / g; additionally or alternatively about 100 m2 / g, about 125 m2 / g, about 150 m2 / g, about 175 m2 / g, about 200 m2 / g, about 225 m2 / g, about 250 m2 / g, about 275 m2 / g, about 300 m2 / g g, about 325 m2 / g, about 350 m2 / g, about 375 m2 / g, about 400 m2 / g , about 425 m2 / g, about 450 m2 / g, about 475 m2 / g, about 500 m2 / g, about 525 m2 / g, about 550 m2 / g, about 575 m2 / g, about 600 m2 / g, about 625 m2 / g, about 650 m2 / g, about 675 m2 / g, about 700 m2 / g, about 725 m2 / g, about 750 m2 / g, about 775 m2 / g, about 800 m2 / g, about 825 m2 / g, about 850 m2 / g, about 875 m2 / g, about 900 m2 / g, about 925 m2 / g, about 950 m2 / g, about 975 m2 / g, or about 1000 m2 / g.

[0038] In one or more aspects, the inorganic support material is characterized by a pore volume of from about 0.10 cc / g to about 0.4 cc / g; additionally or alternatively from about 0.10 g / cc to about 0.3 g / cc; additionally or alternatively from about 0.1 g / cc to about 0.25 g / cc; additionally or alternatively about 0.1 g / cc, about 0.12 g / cc, about 0.14 g / cc, about 0.16 g / cc, about 0.18 g / cc, about 0.2 g / cc, about 0.22 g / cc, about 0.24 g / cc, about 0.26 g / cc, about 0.28 g / cc, about 0.3 g / cc, about 0.32 g / cc, about 0.34 g / cc, about 0.36 g / cc, about 0.38 or about 0.4 g / cc.

[0039] In one or more aspects, the inorganic support material is characterized by a pore size of from about 0.5 nm to about 5 nm; additionally or alternatively from about 1 nm to about 5 nm; additionally or alternatively from about 2.5 nm to about 5 nm; additionally or alternatively about 0.5 nm, about 0.6 nm, about 0.8 nm, about 1 nm, about 1.2 nm, about 1 .4 nm, about 1 .6 nm, about 1 .8 nm, about 2 nm, about 2.2 nm, about 2.4 nm, about 2.6 nm, about 2.8 nm, about 3 nm, about 3.2 nm, about 3.4 nm, about 3.6 nm, about 3.8 nm, about 4 nm, about 4.2 nm, about 4.4 nm, about 4.6 nm, about 4.8 nm, or about 5 nm.

[0040] The surface area of the inorganic support material may be determined using any suitable method. An example of a suitable method includes the Brunauer, Emmett, andTeller (“BET”) method, which measures the quantity of nitrogen adsorbed on the support. Additionally or alternatively , the surface area of the support can be measured by a mercury intrusion method such as is described in ASTM UOP 578-02, entitled "Automated Pore Volume and Pore Size Distribution of Porous Substances by MERCURY Porosimetry," which is incorporated herein by reference in its entirety.

[0041] In an aspect, the inorganic support may be present in an amount such that it comprises the balance of the OCIS when all other components are accounted for.

[0042] In one or more aspects, the OCIS comprises one or more transition metals and one or more dopants. In other aspects, the OCIS comprises two or more transition metals and one or more dopants. In an aspect, the one or more transition metals are selected from the atoms in Group 8, Group 9, Group 10, Period 5, Period 6 or combinations thereof. In one or more aspects, the OCIS comprises a platinum group metal.

[0043] In some aspects, the transition metal is a Group 10 metal. In some aspects, the transition metal is a Group 11 metal. In one or more aspects, the transition metal comprises gold (Au), palladium (Pd), platinum (Pt) or combinations thereof. In other aspects, the transition metal comprises Au, Pt or combinations thereof.

[0044] Generally, any metal in the OCIS can have any positive oxidation state available to the metal atom. In an aspect, the transition metal has an oxidation state of from +2 to +6; additionally or alternatively, from +2 to +4; additionally or alternatively, from +2 to +3 additionally or alternatively +2, +3, +4, +5, or +6. In one or more aspects, the transition metal can assume oxidation states ranging from -3 to +5.

[0045] In a non-limiting aspect, the transition metal is a transition metal salt. In one or more aspects, the transition metal salt comprises halides, carboxylates, p-diketonates, or combinations thereof. For example, the transition metal salt may comprise palladium halides, palladium carboxylates, palladium -diketonates, platinum halides, platinum carboxylates, platinum p-diketonates, gold halides, gold carboxylates, gold p- diketonates, strontium halides, strontium carboxylates, and strontium p-diketonates. In one or more aspects, the transition metal salt comprises a chloride, a nitrate or an acetate.

[0046] In or more aspects, the OCIS has one or more transition metals present in an amount ranging from about 0.1 weight percent (wt.%) to about 20 wt.% based on the total weight of the OCIS; additionally or alternatively from about 0.5 wt.% to about 15wt.%; additionally or alternatively from about 1 wt.% to about 10 wt.%; additionally or alternatively from about 1 wt.% to about 5 wt.%; additionally or alternatively about 0.1 wt.%, about 0.25 wt.%, about 0.5 wt.%, about 0.75 wt.%, about 1 wt.%, about 1.25 wt.%, about 1.5 wt.%, about 1.75 wt.%, about 2 wt.%, about 2.25 wt.%, about 2.5 wt.%, about2.75 wt.%, about 3 wt.%, about 3.25 wt.%, about 3.5 wt.%, about 3.75 wt.%, about 4 wt.%, about 4.25 wt.%, about 4.5 wt.%, about 4.75 wt.%, about 5 wt.%, about 5.25 wt.%, about 5.5 wt.%, about 5.75 wt.%, about 6 wt.%, about 6.25 wt.%, about 6.5 wt.%, about6.75 wt.%, about 7 wt.%, about 7.25 wt.%, about 7.5 wt.%, about 7.75 wt.%, about 8 wt.%, about 8.25 wt.%, about 8.5 wt.%, about 8.75 wt.%, about 9 wt.%, about 9.25 wt.%, about 9.5 wt.%, about 9.75 wt.%, about 10 wt.%, about 10.25 wt.%, about 10.5 wt.%, about 10.75 wt.%, about 11 wt.%, about 11 .25 wt.%, about 11.5 wt.%, about 11 .75 wt.%, about 12 wt.%, about 12.25 wt.%, about 12.5 wt.%, about 12.75 wt.%, about 13 wt.%, about 13.25 wt.%, about 13.5 wt.%, about 13.75 wt.%, about 14 wt.%, about 14.25 wt.%, about 14.5 wt.%, about 14.75 wt.%, about 15 wt.%, about 15.25 wt.%, about 15.5 wt.%, about 15.75 wt.%, about 16 wt.%, about 16.25 wt.%, about 16.5 wt.%, about 16.75 wt.%, about 17 wt.%, about 17.25 wt.%, about 17.5 wt.%, about 17.75 wt.%, about 18 wt.%, about 18.25 wt.%, about 18.5 wt.%, about 18.75 wt.%, about 19 wt.%, about 19.25 wt.%, about 19.5 wt.%, about 19.75 wt.%, or about 20 wt.%.

[0047] In one or more aspects, the OCIS has platinum present in an amount ranging from about 0.001 wt.% to about 1 wt.%; additionally or alternatively from about 0.01 wt.% to about 1 wt.%; additionally or alternatively from about 0.1 wt.% to about 1 wt.%; additionally or alternatively from about 0.25 wt.% to about 1 wt.%.

[0048] In one or more aspects the OCIS has gold present in an amount of from about 0.05 wt.% to about 1 wt.%; additionally or alternatively from about 0.075 wt.% to about 1 wt.%, additionally or alternatively from about 0.1 wt.% to about 1 wt.%: additionally or alternatively from about 0.25 wt.% to about 1 wt.%.

[0049] In an aspect, the OCIS comprises a dopant. Nonlimiting examples of dopants suitable for use in the OCIS include lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), strontium (Sr), bismuth (Bi), salts thereof or combinations thereof. In an aspect, the OCIS comprises Sr.

[0050] In one or more aspects, strontium is present in the OCIS in an amount ranging from about 0.001 wt.% to about 0.5 wt.%; additionally or alternatively from about 0.01 wt.% to about 0.5 wt.%; additionally or alternatively from about 0.05 wt.% to about 0.5 wt.%;additionally or alternatively from about 0.1 wt.% to about 0.5 wt.%.

[0051] In one or more aspects, the OCIS comprises gold, platinum and strontium wherein platinum is present in an amount ranging from about 0.001 wt.% to about 1 wt.%; additionally or alternatively from about 0.01 wt.% to about 1 wt.%; additionally or alternatively from about 0.1 wt.% to about 1 wt.%; additionally or alternatively from about 0.25 wt.% to about 1 wt.%; gold is present in an amount of from about 0.05 wt.% to about 1 wt.%; additionally or alternatively from about 0.075 wt.% to about 1 wt.%, additionally or alternatively from about 0.1 wt.% to about 1 wt.%: additionally or alternatively from about 0.25 wt.% to about 1 wt.%; and strontium is present in an amount ranging from about 0.001 wt.% to about 0.5 wt.%; additionally or alternatively from about 0.01 wt.% to about 0.5 wt.%; additionally or alternatively from about 0.05 wt.% to about 0.5 wt.%; additionally or alternatively from about 0.1 wt.% to about 0.5 wt.%.

[0052] In one or more aspects, a method of preparing the OCIS comprises washing the inorganic support material to form a washed inorganic support material; impregnation of the washed inorganic support material with a platinum salt and a strontium salt to form a bimetallated support; aging of the bimetallated support to form an aged bimetalllated support; reduction of the aged bimetallated support to form an aged reduced bimetallated support; impregnation of the aged reduced bimetallated support with a gold salt to form a trimetallated support and reduction of the trimetallated support to form a reduced trimetallated support and aging of the reduced trimetallated support to form an OCIS.

[0053] In an aspect of the present methodology, the inorganic support material is washed. Washing the inorganic support material may reduce the amount of impurities (e.g., fines) present in the inorganic support material. The term washing, as used herein, is meant to include any process where a wash liquid (e.g., water) in excess of the inorganic support material's pore volume is contacted with the support. Several washings may be carried out in order to substantially reduce the amount of impurities present in the inorganic support material. In some aspects, the inorganic support material may be subjected to at least 1 washing in order to remove a substantial amountof the impurities. In other aspects, the inorganic support material may be subjected to from about 3 to about 10 washings in order to reduce the amount of impurities in order to meet some user and / or process goal. In an aspect, the wash liquid is distilled or deionized water having a pH of from about 5 to about 9. The washing temperature may range from about 70 °F (21 °C) to about 200 °F (93.3 °C), additionally or alternatively from about 80 °F (27 °C) to about 130 °F (54 °C), additionally or alternatively from about 90 °F (32 °C) to about 110 °F (43 °C). The washing time may range from about 5 minutes to about 60 minutes per wash, additionally or alternatively from about 15 minutes to about 30 minutes per wash. Hereinafter, the aforementioned conditions are termed “washing conditions.” The resulting inorganic support material is termed a washed inorganic support material.

[0054] In some aspects of the presently disclosed methodology, the washed inorganic support material is thermally treated. Herein thermally treated may involve drying and / or calcining of the washed inorganic support material. In one or more aspects, the washed inorganic support is dried. Drying can be carried out in air or a gas, such as for example nitrogen, hydrogen, oxygen, or any inert gas (e.g., argon), or any compatible combinations thereof. As an example, the washed inorganic support can be dried in the presence of a gas comprising nitrogen, oxygen, or both, for example enriched air or diluted air, such that it contains from about 0.1 vol.% to about 100 vol.% nitrogen, alternatively from about 0.1 vol.% to about 60 vol.% nitrogen, or alternatively from about 0.1 vol.% to about 30 vol.% nitrogen. In an aspect, the gas is a mixture of air and nitrogen. The air or gas can be circulating, moving, or static. In an aspect, during drying the washed inorganic support can be stationary, or moving, such as for example in a rotary dryer.

[0055] In one or more aspects, the washed inorganic support is calcined. Calcining of the washed inorganic support can be carried out using stationary, or moving equipment, such as for example in a rotary calciner. During the calcination step, the temperature can be optionally increased from ambient temperature or the drying temperature to a calcination temperature in a controlled manner, such as through a series of temperature increases followed by temperature hold periods (e.g, stepwise). Calcination temperatures may range of from about 500 °F (260 °C) to about 1500 °F (816 °C), alternatively from about 700 °F (371 °C) to about 1100 °F (593 °C), or alternatively from about 850 °F (454 °C) to about 1100 °F (593 °C). Calcination times may range fromabout 0.5 to about 5 hours, or alternatively from about 0.5 to about 1.5 hours. In such aspects, the calcination may be carried out in an oxygen-containing atmosphere, alternatively the calcination may be carried out in air, alternatively, the calcination may be carried out in “dry” air. Herein dry air refers to air having a dew point of less than about -40 °F (-40 °C).

[0056] Hereinafter, the present disclosure refers to the conditions for drying of any of the materials or compositions disclosed herein as “standard drying conditions.” Hereinafter, the conditions for calcination of any of the materials or compositions disclosed herein are referred to as “standard calcination conditions.” It is to be understood the term “standard calcination conditions” and / or “standard drying conditions” refer to the ranges of temperature, time, and all other factors described herein for the washing, drying and calcination of the support, respectively. Hereinafter the resulting material is termed the treated support.

[0057] In an aspect, the methodology further comprises impregnating the treated support with one or more transition metal salts. In an aspect, the transition metal salts comprise a platinum-containing compound such as a platinum salt and a strontium- containing compound such as a strontium salt. Exemplary platinum and strontium salts suitable for use are disclosed herein.

[0058] The transition metal may be added to the treated support by employing any suitable methodology such as ion-exchange, incipient wetness impregnation, pore fill impregnation, chemical vapor deposition, deposition precipitation (DP), reductive deposition, strong electrostatic adsorption (SEA), charge-enhanced dry impregnation (CEDI), and liquid-phase reduction. In an aspect, the transition metal is added to the treated support by impregnation with a metal-containing solution (e.g., platinum salt solution, strontium salt solution).

[0059] In one or more aspects, an OCIS of the present disclosure is prepared by contacting of a platinum salt and a strontium salt with a treated support to form a bimetallated support. Contacting may be carried out using any of the aforementioned techniques (e.g., impregnation, incipient wetness, etc.) under one or more of the following conditions: a temperature of from about 20 °C to about 40 °C; additionally or alternatively from about 25 °C to about 40 °C; additionally or alternatively from about 25 °C to about 35 °C and for a contacting time of from about 10 minutes to about 24 hours;additionally or alternatively from about 1 hour to about 12 hours; additionally or alternatively from about 2 hours to about 10 hours.

[0060] A method of the present disclosure may further comprise reduction of the bimetallated support. Reduction of the bimetallated support may be carried out using any suitable methodology. In some aspects, reduction can comprise contacting the bimetallated support with a reducing agent such as hydrogen for a suitable time period. As another example, reduction may be carried out by contacting the bimetallated support with a reducing agent. For example, reduction of the bimetallated support may be carried out in the presence of a salt OZ, where O denotes an alkali metal cation or an alkaline earth metal cation and Z denotes an anion selected from the group consisting of halides, sulfate, formate, phosphate, and nitrate.

[0061] In another aspect, the reducing agent comprises sodium formate. Reduction of the bimetallated support may be carried out under one or more of the following conditions a contacting temperature of from about 50 °C to about 100 °C; additionally or alternatively from about 60 °C to about 100 °C; additionally or alternatively from about 60 °C to about 100 °C; a contacting time of from about 2 hours (hrs) to about 48 hrs; additionally or alternatively from about 2 hrs to about 24 hrs; additionally or alternatively from about 6 hrs to about 12 hrs; and a transition metal to reducing agent molar ratio of from about 1000:1 to about10:1 ; additionally or alternatively from about 800:1 to about 50:1 ; additionally or alternatively from about100:1 to about 20:1.

[0062] Hereinafter the conditions under which reduction of metal-containing compositions are reduced are generally termed “reducing conditions." The reduced bimetallated support may be aged by thermal treatment under conditions including a temperature of from about 50 °C to about 150°C ; additionally or alternatively from about 50°C to about 150°C; additionally or alternatively from about 75°C to about 150°C and a time period of from about 1 hour to about 24 hours; additionally or alternatively from about 2 hours to about 12 hours or about 4 hours to about 10 hours. Hereinafter these conditions are referred to as “aging conditions. The resulting material is termed an aged reduced bimetallated support.

[0063] The aged reduced bimetallated support may be used without any further treatment in the preparation of the OCIS. Alternatively, the aged reduced bimetallated support may be washed, dried and / or calcined under washing conditions, drying conditions and / or calcining conditions, respectively.

[0064] In one or more aspects, the reduced bimetallated support is contacted with a gold salt under metallating conditions to form a trimetallated support which can be subsequently reduced, under reducing conditions to form a reduced trimetallated support. The reduced trimetallated support may be aged, washed, dried and / or calcined under aging conditions, washing conditions, drying conditions and / or calcining conditions, respectively to form an OCIS. In one or more aspects, the OCIS comprises Au, Pt and Sr which may be present in a molar ratio of from about 1 :50:50 to about 1 :1 :0.5.

[0065] In one or more aspects, the OCIS prepared as disclosed herein is characterized by a core-shell structure. Core-shell structured catalysts are a relatively new class of nanomaterials that allow a controlled integration of the functions of complementary materials with novel compositions and morphologies.

[0066] In one or more aspects, the OCIS may be contacted with a sugar (e.g., glucose) under conditions suitable for formation of one or more sugar oxidation products. In an aspect, the sugar comprises glucose and the one or more sugar oxidation products comprise glucaric acid, gluconic acid or combinations thereof. In one or more aspects, the OCIS selectively oxidizes glucose to form glucaric acid such that the yield of glucaric acid produced is increased by from about 10% to about 100%, additionally or alternatively from about 20% to about 80%, additionally or alternatively from about 25% to about 75%, additionally or alternatively from about 30% to about 70%, additionally or alternatively from about 35% to about 65%, additionally or alternatively from about 45% to about 55%, additionally or alternatively about 50% when compared to the amount of glucaric acid formed in the absence of an OCIS. For example, the selectivity of an OCIS may be compared to that of an oxidation catalyst comprising a carbon-supported gold- platinum-strontium composition prepared other than disclosed herein.

[0067] Disclosed herein are novel oxidation catalysts which exhibit increased selectivity towards glucaric acid production and on path intermediates such as guluronic acid, glucuronic acid and gluconic acid. In one or more aspects, loading of the metals in a methodical and sequential order, rather than all together in one pot, shifts the selectivity of the reaction to improved production of glucaric acid and on path intermediates guluronic acid, glucuronic acid and gluconic acid while also lowering the carbon loss.

[0068] In one or more aspects, the OCIS selectivity oxidizes glucodialdose to glucaric acid at high dry yields and on path intermediates such as guluronic acid, glucuronic acidand gluconic acid. In one or more aspects, the OCIS comprises 0.3 wt.% Au, 0.2 wt.% Pt, a small amount of dopant salt such as strontium nitrate, strontium chloride, or lanthanum nitrate is added to form OCIS. The OCIS may contain increased loadings of gold and platinum. In one or more aspects, the OCIS has increased selectivity towards glucaric acid starting from dextrose feedstock and producing a product mixture comprising gluconic acid and glucaric acid, also known as GOGA.

[0069] Disclosed herein are catalysts that provide the opportunity to increase catalytic activity and selectivity towards target products. An OCIS of the present disclosure can also utilize glucodialdose as a reagent to make glucaric acid at dry yields that are increased by from about 10% to about 100%; additionally or alternatively form about 20% to about 90%, additionally or alternatively from about 30% to about 80% wherein compared to the yields obtained in the presence of a differing catalyst.

[0070] In one or more aspects, the OCIS produces glucaric acid in yields of equal to or greater than about 60 weight percent (wt.%) on a dry basis starting from glucodialdose, and produces a mixture of gluconic acid and 30 glucaric acid at 30 wt.% and 50 wt.% dry basis, respectively, using dextrose as a reagent. An OCIS of the present disclosure is characterized by a surprising change in product selectivity as earlier oxidation catalysts exhibited selectivity that favored gluconic acid production. For example, a product mixture prepared using a Pt-Au / C catalyst typically produced gluconic acid at 85 wt.% dry basis with glucaric acid at 15 wt.% dry basis when using glucose as a reagent or about 35 wt.% dry basis glucaric acid when using glucodialdose as a reagent.

[0071] The OCIS disclosed herein represents an improvement over conventional oxidation catalysts as most catalysts do not want the core shell formation. However, as disclosed herein the OCIS formed by strontium and platinum loading first and together, and then the gold sequentially has high advantages for this oxidation reaction to form glucaric acid and on path intermediates such as guluronic acid, glucuronic acid and gluconic acid.ADDITIONAL DISCLOSURE

[0072] The following are additional nonlimiting exemplary aspects of the presently disclosed subject matter

[0073] A first aspect which is a method of a preparing an oxidation catalyst comprising contacting a first transition metal salt and a dopant with a support material to form a bimetallated support; reducing the bimetallated support by contacting the bimetallatedsupport with a reducing agent to form a reduced bimetallated support; aging the reduced bimetallated support; contacting the aged reduced bimetallated support with a second transition metal salt to form a trimetallated support; reducing the trimetallated support by contacting the trimetallated support with a reducing agent to form a reduced trimetallated support; and aging the reduced trimetallated support to form the oxidation catalyst.

[0074] A second aspect which is the method of the first aspect wherein aging the reduced bimetallated support comprises aging the reduced bimetallated support by thermally treating the reduced bimetallated support at a temperature of from about 50 °C to about 150°C for a time period of from about 1 hour to about 24 hours to form an aged reduced bimetallated support, and wherein aging the reduced trimetallated support comprises aging the reduced trimetallated support by thermally treating the reduced trimetallated support at a temperature of from about 50 °C to about 150°C for a time period of from about 1 hour to about 24 hours to form the oxidation catalyst wherein the first transition metal salt and the second transition metal salt differ.

[0075] A third aspect which is the method of any of the first through second aspects wherein the support material comprises carbon, aluminas, silicas, titanias, zirconias, aluminosilicates, spinels or combinations thereof.

[0076] A fourth aspect which is the method of any of the first through third aspects wherein the support material comprises carbon.

[0077] A fifth aspect which is the method of the fourth aspect wherein the support material comprises less than about 20% micropores.

[0078] A sixth aspect which is the method of any of the first through fifth aspects wherein the support material has a surface area of from about 100 m2 / g to about 1000 m2 / g.

[0079] A seventh aspect which is the method of any of the first through sixth aspects wherein the support material has a pore volume of from about 0.10 cc / g to about 0.4 cc / g.

[0080] An eighth aspect which is the method of any of the first through seventh aspects wherein the support material has a pore size of from about 0.5 nm to about 5 nm.

[0081] A ninth aspect which is the method of any of the first through eighth aspects wherein the first transition metal salt comprises platinum.

[0082] A tenth aspect which is the method of any of the first through ninth aspects wherein the second transition metal salt comprises gold.

[0083] An eleventh aspect which is the method of any of the first through tenth aspects wherein the dopant is selected from the group consisting of lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), strontium (Sr), bismuth (Bi), salts thereof and combinations thereof.

[0084] A twelfth aspect which is the method of any of the first through eleventh aspects wherein the dopant comprises strontium.

[0085] A thirteenth aspect which is the method of any of the first through twelfth aspects wherein the first transition metal salt comprises platinum, the second transition metal comprises gold and the dopant comprises strontium.

[0086] Afourteenth aspect which is the method of the thirteenth aspect wherein the gold, platinum and strontium are present in a molar ratio of from about 1 :50:50 to about 1 :1 :0.5.

[0087] A fifteenth aspect which is the method of any of the first through fourteenth aspects further comprising washing the support material, the bimetallated support, the trimetallated support or combinations thereof.

[0088] A sixteenth aspect which is the method of any of the first through fifteenth aspects further comprising drying the support material, the bimetallated support, the trimetallated support or combinations thereof.

[0089] A seventeenth aspect which is the method of any of the first through sixteenth aspects further comprising calcining the support material, the bimetallated support, the trimetallated support or combinations thereof.

[0090] An eighteenth aspect which is the method of any of the first through seventeenth aspects wherein contacting of the first transition metal salt, the second transition metal salt or both comprises ion-exchange, incipient wetness impregnation, pore fill impregnation, chemical vapor deposition, deposition precipitation (DP), reductive deposition, strong electrostatic adsorption (SEA), charge-enhanced dry impregnation (CEDI), liquid-phase reduction or combinations thereof.

[0091] A nineteenth aspect which is the method of any of the first through eighteenth aspects wherein the reducing agent comprises a salt OZ, where O denotes an alkali metal cation or an alkaline earth metal cation and Z denotes an anion selected from the group consisting of halides, sulfate, formate, phosphate, and nitrate.

[0092] A twentieth aspect which is a method of selectively oxidizing glucose comprising contacting glucose with the oxidation catalyst of claim 1 in the presence of oxygen under conditions suitable for the formation of glucose oxidation products.

[0093] A twenty-first aspect which is the method of the twentieth aspect wherein the glucose oxidation products comprise glucaric acid, gluconic acid or combinations thereof.

[0094] A twenty-second aspect which is the method of any of the twentieth through twenty-first aspects wherein the yield of glucaric acid produced is increased by from about 10% to about 100% when compared to glucaric acid prepared in the absence of the catalyst of claim 1 .

[0095] A twenty-third aspect which is a method of selectively oxidizing glucodialdose comprising contacting glucodialdose with the oxidation catalyst of claim 1 in the presence of oxygen under conditions suitable for the formation of glucose oxidation products.EXAMPLES

[0096] The aspects having been generally described, the following reaction conditions examples are given as particular aspects of the disclosure and to demonstrate the practice and advantages thereof. It is understood that the examples are given by way of illustration and are not intended to limit the specification or the claims in any manner. EXAMPLE 1

[0097] Reagents used in the preparation of an OCIS as exemplified herein include the metal salts; HAuCkSFW, PhPtCleeHsO, and Sr(NOs)2; and the carrier / support material Meso C+ T1 .6 extrudate. MESO C + T1 .6 extrudate refers to a SICAT activated carbon commercially available from SICAT -ACM GMbh. OCIS samples was prepared generally as follows: carrier (i.e., support) pre-treatment was carried out by being washed 6 times with a total of 96 L deionized (DI) water to remove fines (visual inspection) and dried at 105 °C for greater than 12 hours before impregnation. Metal loading was carried by adding 24.0117 g of a F^PtCle solution (the salt was prediluted from 25g in 500 mL DI water), and 0.4038 g of g Sr(NOs)2 salt to 179.98 g DI water. The mixture was stirred so a fully homogenized solution was obtained. The solution was added rapidly to 120 g of the carrier (both carrier and solution at room temperature) and the resulting mixture swirled and aged for 2 hours followed by decanting of the impregnation supernatant to obtain the bimetallated carrier. Then 14.4 g of solid sodium formate was dissolved in156 mL DI water and the solution was preheated. The Pt / Sr-loaded catalyst (wet) was placed in an oven at 75 °C for 1 hour and the sodium formate solution was added to the catalyst rapidly to form a mixture. The mixture was swirled, covered and placed back in the oven at 75 °C to age for 6 hours before being removed and allowed to cool to room temperature. Liquid was decanted from the mixture to obtain the reduced bimetallated carrier. The reduced bimetallated carrier was washed a minimum of 6 times with DI water to remove any remaining chlorides before being dried in the oven at 105 °C for a minimum of 12 hours to form a dried reduced bimetallated carrier.

[0098] A gold solution was prepared by adding 4.83 g of a HAuCL solution (the salt is prediluted from 50g in 1000 mL DI water) to 179.16 g DI water which was then agitated to form a fully homogenized solution. The gold solution was then rapidly added to the 120 g of the dried reduced bimetallated carrier (both catalyst and solution at room temperature) which was swirled and then aged for 2 hours before decanting the impregnation supernatant to obtain a trimetallated carrier. A sodium formate solution having 10.721 g solid of sodium formate dissolved in 168.262 mL DI water was prepared. The trimetallated carrier and sodium formate solution were both preheated in an oven at 75 °C for 1 hour before the sodium formate solution was added to the trimetallated carrier rapidly to form a mixture. The mixture was swirled, covered and put back in the oven at 75 °C to age for 6 hours. After aging the mixture was cooled to room temperature, liquid decanted and the reduced trimetallated support washed a minimum of 6 times with DI water to remove any remaining chlorides. The reduced, washed trimetallated support was dried in the oven at 105 °C for a minimum of twelve hours to produce the OCIS. A total of eight catalyst samples were prepared with the metal loadings presented in Table 1 .Table 1

[0099] The catalysts were used to catalyze the oxidation of either glucose or glucodialdose and the type and amount of oxidation products determined. The amount of glucaric acid produced and percentage carbon loss for a catalyst prepared by the addition of 0.38 wt.% Pt to a carbon support followed by the addition of 0.52 wt.% Au(Sample F); a catalyst prepared by the addition of 0.38 wt.% Pt and 0.14 wt.% Sr to a carbon support followed by the addition of 0.52 wt.% Au (Sample G) and a catalyst prepared by the addition of 0.48 wt.% Pt and 0.19 wt.% Sr to a carbon support followed by the addition of 0.46 wt.% Au (Sample H) is presented in Figure 1 .

[0100] The amount of glucaric acid produced as a function of catalyst passes was also determined and the results are presented in Figure 2 for catalyst sample A through H while the normalized values are presented in Figure 3. With reference to Figure 3, third party oxidation catalysts were assayed for their reactivity in the oxidation of glucose to glucaric acid and were designated samples M through Q where M was designated as the benchmark catalyst. Figure 4 is a bar graph of the percentage carbon loss for the indicated catalyst samples.

[0101] The catalyst activity was assayed using glucodialdose (GDA) instead of glucose as the reactant and the results are presented both in terms GDA conversion and selectivity for the production of glucaric acid in Figure 5. A subset of catalyst samples were assayed for the specific production of glucaric acid and on-path intermediates (e.g., GDA) for samples X, G and H is presented as a bar graph in Figure 6. Sample X is a control sample where the catalyst was prepared by contacting simultaneously 0.52 wt.% Au, 0.38 wt.% Pt and 0.14 wt.% Sr on carbon.

[0102] The amount of on-path intermediates (e.g., GDA), percentage carbon loss, cumulative carbon yield of glucaric acid and cumulative carbon produced by the indicated catalyst samples are presented as bar graphs in Figures 7, 8, 9, and 10 respectively. A scatter plot of the carbon loss as a function of catalyst type was normalized to the benchmark catalyst M for glucaric acid throughput and the results are presented in Figure 11 .

[0103] Plant scale oxidations were carried to establish the product selectivity for an OCIS of the type disclosed herein (Sample G) with a control catalyst. The control catalyst was a GEN I catalyst. Samples X0-X4 represent the activity of a GEN I catalyst or Catalyst G (U0-U4) at different time points. The amount of glucaric acid produced is compared to the amount of on-path acids produced such as guluronic acid, glucuronic acid and gluconic acid (GO). The results are presented as a bar graph in Figure 12.

[0104] Ten different samples of an OCIS were prepared and used to catalyze pilot scale oxidation reactions (75x larger than lab scale) using GDA as the feedstock. The dry weight percentage of glucaric acid and no-path acids were determined for each sampleand was used to determine the cumulative glucaric acid productivity and the results are presented as bar graphs in Figures 13 and 14, respectively. The selectivity of OCIS samples AA1-AA4 were compared to that of a reference sample. Specifically, the dry weight percentage of gluconic acid, glucaric acid and other on path acids is for various samples of OCIS is presented as a bar graph in Figure 15.

[0105] The subject matter having been shown and described, modifications thereof can be made by one skilled in the art without departing from the spirit and teachings of the subject matter. The aspects described herein are exemplary only and are not intended to be limiting. Many variations and modifications of the subject matter disclosed herein are possible and are within the scope of the disclosed subject matter. Where numerical ranges or limitations are expressly stated, such express ranges or limitations should be understood to include iterative ranges or limitations of like magnitude falling within the expressly stated ranges or limitations (e.g., from about 1 to about 10 includes, 2, 3, 4, etc.; greater than 0.10 includes 0.11 , 0.12, 0.13, etc.). Use of the term "optionally" with respect to any element of a claim is intended to mean that the subject element is required, or additionally or alternatively , is not required. Both alternatives are intended to be within the scope of the claim. Use of broader terms such as comprises, includes, having, etc. should be understood to provide support for narrower terms such as consisting of, consisting essentially of, comprised substantially of, etc.

[0106] Accordingly, the scope of protection is not limited by the description set out above but is only limited by the claims which follow, that scope including all equivalents of the subject matter of the claims. Each and every claim is incorporated into the specification as an aspect of the present disclosure. Thus, the claims are a further description and are an addition to the aspects of the present invention. The discussion of a reference herein is not an admission that it is prior art to the presently disclosed subject matter, especially any reference that may have a publication date after the priority date of this application. The disclosures of all patents, patent applications, and publications cited herein are hereby incorporated by reference, to the extent that they provide exemplary, procedural or other details supplementary to those set forth herein.

Claims

CLAIMSWhat is claimed is:1 . A method of a preparing an oxidation catalyst comprising: contacting a first transition metal salt and a dopant with a support material to form a bimetallated support; reducing the bimetallated support by contacting the bimetallated support with a reducing agent to form a reduced bimetallated support; aging the reduced bimetallated support; contacting the aged reduced bimetallated support with a second transition metal salt to form a trimetallated support; reducing the trimetallated support by contacting the trimetallated support with a reducing agent to form a reduced trimetallated support; and aging the reduced trimetallated support to form the oxidation catalyst2. The method of claim 1 , wherein aging the reduced bimetallated support comprises aging the reduced bimetallated support by thermally treating the reduced bimetallated support at a temperature of from about 50 °C to about 150°C for a time period of from about 1 hour to about 24 hours to form an aged reduced bimetallated support, and wherein aging the reduced trimetallated support comprises aging the reduced trimetallated support by thermally treating the reduced trimetallated support at a temperature of from about 50 °C to about 150°C fora time period of from about 1 hour to about 24 hours to form the oxidation catalyst wherein the first transition metal salt and the second transition metal salt differ.

3. The method of claim 1 , wherein the support material comprises carbon, aluminas, silicas, titanias, zirconias, aluminosilicates, spinels or combinations thereof.

4. The method of claim 1 , wherein the support material comprises carbon.

5. The method of claim 4, wherein the support material comprises less than about 20% micropores.

6. The method of claim 1 , wherein the support material has a surface area of from about 100 m2 / g to about 1000 m2 / g.

7. The method of claim 1 , wherein the support material has a pore volume of from about 0.10 cc / g to about 0.4 cc / g.

8. The method of claim 1 , wherein the support material has a pore size of from about 0.5 nm to about 5 nm.

9. The method of claim 1 , wherein the first transition metal salt comprises platinum.

10. The method of claim 1 , wherein the second transition metal salt comprises gold.11 . The method of claim 1 , wherein the dopant is selected from the group consisting of lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium(Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), strontium (Sr), bismuth (Bi), salts thereof and combinations thereof.

12. The method of claim 1 , wherein the dopant comprises strontium.

13. The method of claim 1 , wherein the first transition metal salt comprises platinum, the second transition metal comprises gold and the dopant comprises strontium.

14. The method of claim 13, wherein the gold, platinum and strontium are present in a molar ratio of from about 1 :50:50 to about 1 :1 :0.5.

15. The method of claim 1 , further comprising washing the support material, the bimetallated support, the trimetallated support or combinations thereof.

16. The method of claim 1 , further comprising drying the support material, the bimetallated support, the trimetallated support or combinations thereof.

17. The method of claim 1 , further comprising calcining the support material, the bimetallated support, the trimetallated support or combinations thereof.

18. The method of claim 1 , wherein contacting of the first transition metal salt, the second transition metal salt or both comprises ion-exchange, incipient wetness impregnation, pore fill impregnation, chemical vapor deposition, deposition precipitation (DP), reductive deposition, strong electrostatic adsorption (SEA), charge-enhanced dry impregnation (CEDI), liquid-phase reduction or combinations thereof.

19. The method of claim 1 , wherein the reducing agent comprises a salt OZ, where O denotes an alkali metal cation or an alkaline earth metal cation and Z denotes an anion selected from the group consisting of halides, sulfate, formate, phosphate, and nitrate.

20. A method of selectively oxidizing glucose comprising: contacting glucose with the oxidation catalyst of claim 1 in the presence of oxygen under conditions suitable for the formation of glucose oxidation products.

21. The method of claim 20, wherein the glucose oxidation products comprise glucaric acid, gluconic acid or combinations thereof.

22. The method of claim 20, wherein the yield of glucaric acid produced is increased by from about 10% to about 100% when compared to glucaric acid prepared in the absence of the catalyst of claim 1 .

23. A method of selectively oxidizing glucodialdose comprising: contacting glucodialdose with the oxidation catalyst of claim 1 in the presence of oxygen under conditions suitable for the formation of glucose oxidation products.

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