CO2 and O2 removers

Abstract

The present invention relates to a CO2 and O2 remover for sufficiently removing CO2 and O2 from a gas. The CO2 and O2 remover contains 65 to 85 weight percent (wt.%) of nickel oxide (NiO), 5 to 20 wt.% of magnesium oxide (MgO), wherein the weight ratio of nickel oxide to magnesium oxide (NiO / MgO) is 4 to 11, and wherein wt.% is based on the weight of the CO2 and O2 remover.

Description

Technical Field

[0001] The present invention relates to a CO2 and O2 (CO2 / O2) remover and a method for preparing the same. Background Art

[0002] For example, in semiconductor manufacturing processes that use an inert gas atmosphere containing nitrogen, helium or argon, a CO2 / O2 remover is required. Reactive gases such as CO2 / O2 need to be removed to make the atmosphere inert.

[0003] WO2013109895 discloses a CO2 adsorbent comprising (i) a magnesium salt, and (ii) at least one salt of a Group IA element, wherein (i) the magnesium salt and (ii) the salt of the Group IA element are present in a molar ratio of about 8:1 to 3:1.

[0004] Prior art literature

[0005] Patent Literature

[0006] WO2013109895 SUMMARY OF THE INVENTION

[0008] The purpose is to provide a CO2 / O2 remover that can fully remove CO2 and O2 from gas.

[0009] One aspect of the present invention relates to a CO2 and O2 remover, which comprises: 65 to 85 weight percent (wt.%) nickel oxide (NiO), 5 to 20 wt.% magnesium oxide (MgO), wherein the weight ratio of nickel oxide to magnesium oxide (NiO / MgO) is 4 to 11, and wherein the wt.% is based on the weight of the CO2 and O2 remover.

[0010] Another aspect of the present invention relates to a method for preparing a CO2 and O2 remover, the method comprising the steps of mixing a nickel compound and a magnesium compound, and calcining the mixture to form a CO2 and O2 remover, wherein the CO2 and O2 remover contains 65 to 85 weight percent (wt.%) of nickel oxide (NiO), 5 to 20 wt.% of magnesium oxide (MgO), wherein the weight ratio of nickel oxide to magnesium oxide (NiO / MgO) is 4 to 11, and wherein the wt.% is based on the weight of the CO2 and O2 remover.

[0011] Another aspect of the present invention relates to a method for removing CO2 and O2 from air, the method comprising the steps of: placing a CO2 and O2 remover in a container, wherein the CO2 and O2 remover comprises 65 to 85 weight percent (wt.%) of nickel oxide (NiO), 5 to 20 wt.% of magnesium oxide (MgO), wherein the weight ratio of nickel oxide to magnesium oxide (NiO / MgO) is 4 to 11, and wherein the wt.% is based on the weight of the CO2 and O2 remover; and passing air through the container.

[0012] Through the present invention, CO2 and O2 can be fully removed from the gas.

[0013] BRIEF DESCRIPTION OF THE DRAWINGS

[0014] [ Figure 1 ] Figure 1 An example of a cylindrical CO 2 / O 2 remover 10 having a circular cross section is shown.

[0015] [ Figure 2 ] Figure 2 An example of a cylindrical CO2 / O2 remover 20 having a trilobal cross-section is shown.

[0016] Description of Embodiments

[0017] The CO2 / O2 remover and a method for preparing the same are described below.

[0018] The CO 2 / O 2 remover includes 65 to 85 weight percent (wt. %) of nickel oxide (NiO), and 5 to 20 wt. % of magnesium oxide (MgO), based on the weight of the CO 2 / O 2 remover.

[0019] Based on the weight of the CO2 / O2 remover, NiO is 66.5wt.% or more in one embodiment, 67.5wt.% or more in another embodiment, 68.5wt.% or more in another embodiment, 69wt.% or more in another embodiment, 70.5wt.% or more in another embodiment, and 71.2wt.% or more in another embodiment. Based on the weight of the CO2 / O2 remover, NiO is 83.5wt.% or less in one embodiment, 82.1wt.% or less in another embodiment, 80.5wt.% or less in another embodiment, 78.6wt.% or less in another embodiment, 76wt.% or less in another embodiment, and 74.5wt.% or less in another embodiment.

[0020] Based on the weight of the CO2 / O2 remover, MgO is 5.5 wt.% or more in one embodiment, 6.2 wt.% or more in another embodiment, 7.5 wt.% or more in another embodiment, 7.9 wt.% or more in another embodiment, 8.9 wt.% or more in another embodiment, 9.9 wt.% or more in another embodiment, and 10.5 wt.% or more in another embodiment. Based on the weight of the CO2 / O2 remover, MgO is 19.2 wt.% or less in one embodiment, 18.1 wt.% or less in another embodiment, 17.5 wt.% or less in another embodiment, 16.3 wt.% or less in another embodiment, 15.5 wt.% or less in another embodiment, 14.8 wt.% or less in another embodiment, 13.2 wt.% or less in another embodiment, 12.5 wt.% or less in another embodiment, 11.1 wt.% or less in another embodiment, and 9.9 wt.% or less in another embodiment.

[0021] The weight ratio of NiO and MgO (NiO / MgO) is 4 to 11. The weight ratio of NiO and MgO (NiO / MgO) is 4.5 or more in one embodiment, 5.1 or more in another embodiment, 5.7 or more in another embodiment, 6.1 or more in another embodiment, 6.9 or more in another embodiment, 7.5 or more in another embodiment, and 8.1 or more in another embodiment. The weight ratio of NiO and MgO (NiO / MgO) is 10.5 or less in another embodiment, 9.8 or less in another embodiment, 5.7 or less in another embodiment, 9 or less in another embodiment, 8.2 or less in another embodiment, 7.5 or less in another embodiment, and 6.8 or less in another embodiment. The CO2 / O2 remover containing NiO and MgO within the above-mentioned weight ratio range can fully remove CO2 and O2 simultaneously.

[0022] In one embodiment, the CO2 / O2 removal agent further comprises one or more other metal oxides selected from silicon oxide (SiO2), aluminum oxide (Al2O3), sodium oxide (Na2O) and mixtures thereof. In another embodiment, the CO2 / O2 removal agent further comprises one or more other metal oxides selected from silicon oxide (SiO2), aluminum oxide (Al2O3) and mixtures thereof.

[0023] In another embodiment, the CO2 / O2 remover contains SiO2 in addition to NiO and MgO. Based on the weight of the CO2 / O2 remover, SiO2 is 1wt.% or more in one embodiment, 2.2wt.% or more in another embodiment, 2.9wt.% or more in another embodiment, 3.6wt.% or more in another embodiment, 4.5wt.% or more in another embodiment, 5.2wt.% or more in another embodiment, and 6.9wt.% or more in another embodiment. Based on the weight of the CO2 / O2 remover, SiO2 is 20wt.% or less in one embodiment, 17.2wt.% or less in another embodiment, 13.5wt.% or less in another embodiment, 10.3wt.% or less in another embodiment, 8.5wt.% or less in another embodiment, 6.4wt.% or less in another embodiment, and 5.2wt.% or less in another embodiment.

[0024] In one embodiment, the CO2 / O2 remover contains Al2O3 in addition to NiO and MgO. Based on the weight of the CO2 / O2 remover, Al2O3 is 1 wt.% or more in one embodiment, 3.2 wt.% or more in another embodiment, 5.9 wt.% or more in another embodiment, 7.2 wt.% or more in another embodiment, 9.5 wt.% or more in another embodiment, 10.1 wt.% or more in another embodiment, and 11.2 wt.% or more in another embodiment. Based on the weight of the CO2 / O2 remover, Al2O3 is 30 wt.% or less in one embodiment, 26.3 wt.% or less in another embodiment, 22.5 wt.% or less in another embodiment, 18.3 wt.% or less in another embodiment, 15.5 wt.% or less in another embodiment, 12.8 wt.% or less in another embodiment, and 11.6 wt.% or less in another embodiment.

[0025] In one embodiment, the CO2 / O2 remover comprises an alkali metal oxide in addition to NiO and MgO. In another embodiment, the alkali metal oxide is selected from sodium oxide (Na2O), potassium oxide (K2O), lithium oxide (Li2O) and combinations thereof. In another embodiment, the alkali metal oxide comprises sodium oxide (Na2O). Based on the weight of the CO2 / O2 remover, the alkali metal oxide is 0.01wt.% or more in one embodiment, 0.05wt.% or more in another embodiment, 0.09wt.% or more in another embodiment, 0.1wt.% or more in another embodiment, 0.24wt.% or more in another embodiment, 0.33wt.% or more in another embodiment, and 0.42wt.% or more in another embodiment. Based on the weight of the CO2 / O2 remover, the alkali metal oxide is 2 wt.% or less in one embodiment, 1.9 wt.% or less in another embodiment, 1.2 wt.% or less in another embodiment, 0.8 wt.% or less in another embodiment, and 0.6 wt.% or less in another embodiment. In another embodiment, the CO2 / O2 remover may not contain alkali metal oxides or Na2O.

[0026] The CO2 / O2 removal agent compositions described herein, including those listed in Table 1, are not limiting; it is contemplated that a person of ordinary skill in the art of chemistry may make small substitutions or additions of ingredients without substantially changing the desired properties of the CO2 / O2 removal agent. For example, substitutions of oxides of the following elements in an amount of 0.001 to 3.0 wt. % based on the weight of the CO2 / O2 removal agent may be used alone or in combination to achieve similar performance. The composition of the CO2 / O2 removal agent may be determined by performing fluorescent X-ray analysis (XRF analysis) on the CO2 / O2 removal agent.

[0027] The shape of CO2 / O2 remover is not limited. As long as it produces enough removal capacity and strength as CO2 / O2 remover, the CO2 / O2 remover can be in any shape. CO2 / O2 remover is a particle in one embodiment. CO2 / O2 remover is cylindrical or spherical in another embodiment. In one embodiment, the cross section of cylindrical CO2 / O2 remover is selected from circular, elliptical, polygonal, rectangular and multi-lobed. The cross section of cylindrical CO2 / O2 remover is circular, elliptical or multi-lobed in another embodiment, multi-lobed in another embodiment, and trilobed in another embodiment.

[0028] An example of a cylindrical CO2 / O2 remover 10 having a circular cross section is shown in Figure 1 . The diameter 12 of the cylindrical CO2 / O2 remover 10 is 0.5 to 10 mm in one embodiment, 0.8 to 8.7 mm in another embodiment, 1 to 5.7 mm in another embodiment, and 1.2 to 3.3 mm in another embodiment. The length 13 of the cylindrical CO2 / O2 remover 10 is 0.5 to 30 mm in one embodiment, 1.2 to 21 mm in another embodiment, 2.5 to 16 mm in another embodiment, and 3.2 to 10 mm in another embodiment. The diameter of the elliptical and rectangular cross-sections is the main axis. The diameter of the multi-lobed and polygonal cross-sections is the diameter of the circumscribed circle. An example of a cylindrical CO2 / O2 remover 20 with a trilobal cross-section is shown in Figure 2 .

[0029] In order to obtain the diameter of the cylindrical CO2 / O2 remover 20, the circumscribed circle 21 of the trilobal cross section is taken. The diameter 22 of the trilobal CO2 / O2 remover 20 is 0.5 to 10 mm in one embodiment, 0.8 to 8.7 mm in another embodiment, 1 to 5.7 mm in another embodiment, and 1.2 to 3.3 mm in another embodiment. The length 23 of the trilobal cylindrical CO2 / O2 remover 20 is 0.5 to 30 mm in one embodiment, 1.2 to 21 mm in another embodiment, 2.5 to 16 mm in another embodiment, and 3.2 to 10 mm in another embodiment.

[0030] The CO2 / O2 removal agent is porous in one embodiment. In one embodiment, the pore volume is 0.05 mm 3 / g to 5.0mm 3 / g. The pore volume can be measured using an automatic pore size distribution measuring instrument, such as the BELSORP-mini-II from MicrotracBEL. The surface area (S BET ) in one embodiment is 10 to 1000 m 2 / g, in another embodiment, 32 to 800 m 2 / g, in another embodiment 58 to 645 m 2 / g, in another embodiment, 68 to 500 m 2 / g, in another embodiment, 80 to 320 m 2 / g, in another embodiment 85 to 240 m 2 / g, in another embodiment, 100 to 200 m 2 / g. The surface area can be measured by the BET method (single point method) using N2 gas absorption at liquid nitrogen temperature. A surface area analyzer can be used, such as the Macsorb model-1210 from MOUNTECH.

[0031] In one embodiment, the CO2 / O2 remover is prepared by a precipitation method or a dry method. A Ni compound, a Mg compound and optionally a Si compound, an Al compound and / or a Na compound are prepared. These compounds are mixed and calcined to form the CO2 / O2 remover. In one embodiment, the Al compound can be added to the mixture of the Ni compound and the Mg compound before or after the calcination step.

[0032] As the raw material of the CO2 / O2 remover, such as compounds of Ni, Mg, Al, Si and Na, any compound which gives a metal oxide thereto after calcination can be used.

[0033] The Ni compound may be an oxide, a salt or a mixture thereof. In one embodiment, the Ni compound may be selected from nickel oxide, nickel nitrate, nickel nitrite, nickel hydrogen sulfate and a combination thereof.

[0034] The Mg compound may be an oxide, a salt or a mixture thereof. In one embodiment, the Mg compound may be selected from oxides, magnesium nitrate, magnesium nitrite, magnesium hydrogen sulfate and combinations thereof.

[0035] In one embodiment, the Si compound may be selected from silicon dioxide, diatomaceous earth, liquid glass, and combinations thereof.

[0036] In one embodiment, the Al compound can be selected from boehmite, alumina sol and a combination thereof. The Al compound can also serve as a binder for the Ni compound and the Mg compound. Since the Al compound can serve as a binder for the precipitate, in another embodiment, the Al compound can be mixed separately from the precipitate.

[0037] In one embodiment, the Na compound may be sodium carbonate.

[0038] In one embodiment, the metal compounds can be mixed by a precipitation method, wherein a solution in which the Ni compound and the Mg compound are dissolved is prepared in the precipitation method. The Ni compound and the Mg compound can be soluble salts such as nitrates, nitrites, and bisulfates in another embodiment. In another embodiment, the Ni compound is nickel nitrate. In another embodiment, the Mg compound is magnesium nitrate. In another embodiment, Si compounds and / or Al compounds can be added to dissolve in the solution. In another embodiment, the Si compound can be dissolved in the solution. In one embodiment, the solvent is water. In one embodiment, the solution is heated at 40° C. or higher for 1 hour or more to generate a precipitate. In one embodiment, the precipitate is removed by filtration. In one embodiment, the precipitate is a powder or granules. In another embodiment, the precipitate is optionally mixed with a Si component and / or an Al component.

[0039] The metal compound mixture is calcined. In another embodiment, the calcination is performed after the step of forming the metal compound mixture. The calcination temperature may be 100 to 900° C. in one embodiment, 120 to 680° C. in another embodiment, 180 to 500° C. in another embodiment, and 200 to 400° C. in another embodiment. The calcination time may be 30 minutes or more in one embodiment, 1 hour or more in another embodiment. The calcination time may be 5 hours or less in one embodiment, and 3 hours or less in another embodiment.

[0040] In one embodiment, the mixture of the metal compounds may be shaped into a desired form. The shaping method is not limited, but in one embodiment, the mixture of the metal compounds is shaped by extrusion or molding.

[0041] In one embodiment, the shaped metal compound mixture may be calcined. In one embodiment, the precipitate, optionally mixed with a Si component and / or an Al component, is calcined.

[0042] In one embodiment, the CO2 / O2 remover is reduced by exposure to hydrogen. In one embodiment, the hydrogen is a gas stream at 300 to 550° C. for 5 to 30 hours. In one embodiment, after reduction, an oxide layer is formed on the surface of the CO2 / O2 remover for stabilization, for example, by exposure to a gas containing O2.

[0043] In one embodiment, in the precipitation method, the solution can be prepared separately as an acid solution and an alkaline solution. In one embodiment, the acid solution is prepared by dissolving the Ni compound and the Mg compound in the solution. In one embodiment, the alkaline solution is prepared by dissolving an additional metal compound, such as a Na compound, in the solution. In one embodiment, the Si compound can be dissolved in the acid solution. In one embodiment, the acid solution is gradually added to the alkaline solution until the mixed solution shows a pH of about 7. The precipitate from the mixed solution is removed and calcined.

[0044] In another embodiment, a method for preparing a CO2 and O2 remover comprises the steps of: mixing a nickel compound and a magnesium compound,

[0045] The mixture of the nickel compound and the magnesium compound is molded, and the molded mixture is calcined.

[0046] In another embodiment, a method for preparing a CO2 and O2 remover comprises the steps of: mixing a nickel compound and a magnesium compound,

[0047] The mixture of the nickel compound and the magnesium compound is calcined and the calcined mixture is molded.

[0048] In another embodiment, the CO2 / O2 remover can also be prepared by a dry process. In another embodiment, the Ni compound and the Mg compound are mixed and calcined.

[0049] Use CO2 / O2 removers wherever CO2 and O2 are not needed in the atmosphere. For example, use CO2 / O2 removers in gas purification systems at semiconductor manufacturing sites. Example

[0050] Example 1

[0051] A CO2 / O2 remover was prepared by the following method. An acid solution was prepared by dissolving 7.5 kg of nickel nitrate, 1.6 kg of magnesium nitrate and 0.3 kg of diatomaceous earth in 14.7 kg of ion exchange water. Separately, an alkaline solution was prepared by dissolving 3.9 kg of sodium carbonate in 17.4 kg of pure water. The acid solution was put into the alkaline solution until the mixed solution showed neutrality. The resulting precipitate was taken out by filtering and washing. The precipitate was dried and calcined at 350°C for two hours. The precipitate powder and boehmite were mixed in a weight ratio of 9:1 (precipitate powder: boehmite). A precursor CO2 / O2 remover was formed by extruding the powder mixture with a vertical extruder. The cross-section of the extruded CO2 / O2 remover precursor was a trilobal shape 20 ( Figure 2 ).

[0052] 300cm3 The CO2 / O2 remover is filled into a quartz tube (40mm internal diameter and 950mm long) with an inlet and an outlet. The CO2 / O2 remover is reduced by being exposed to pure hydrogen. Then after cooling to room temperature, the hydrogen is converted to nitrogen. After excluding the hydrogen, the nitrogen containing oxygen is flowed into the tube to stabilize the CO2 / O2 remover by preparing an oxide layer on the surface.

[0053] The surface area (SA) was measured by Macsorb Model-1210 from MOUNTECH BET ) is about 150m 2 / g.

[0054] The composition of the formed CO2 / O2 remover was analyzed by X-ray fluorescence spectrometer (XRF, Supermini-200, Rigaku Corporation).

[0055] Example 2

[0056] A CO 2 / O 2 removing agent was formed in the same manner as in Example 1, except that magnesium nitrate hexahydrate was 2.43 kg and silicon dioxide was 0.14 kg.

[0057] Surface area (SA BET ) is about 150m 2 / g.

[0058] Comparative Example 1

[0059] A CO2 / O2 removal agent was formed in the same manner as in Example 1 except for the composition. The composition of the CO2 / O2 removal agent is shown in Table 1. Surface area (SA BET ) is about 150m 2 / g.

[0060] Measurement

[0061] CO2 removal

[0062] A quartz tube (20 mm inner diameter, 500 mm height) was filled with 40 cm 3 The tube has an inlet at the top and an outlet at the bottom. Reduction is performed to remove the oxide layer. After reduction, 30 ppm of CO2 gas (CO2 / N2) is heated at about 3500 h. -1 The SV flows from the inlet to the outlet through the CO2 / O2 remover. When the CO2 concentration at the outlet increases from zero to 0.5 ppm, the CO2 gas flow stops.

[0063] The CO2 concentration of the outlet gas was measured using a gas chromatograph with a flame ionization detector (FID) and a methanogen (GC-8A / MTN-1, Shimadzu Corporation).

[0064] O2 removal

[0065] 200ppm O2 gas (air / N2) for about 3500h -1 The SV of CO2 / O2 remover flows from the inlet to the outlet. When the O2 concentration at the outlet increases from zero to 7.0 ppm, the O2 gas flow is stopped. The O2 concentration of the outlet gas is measured using a trace oxygen analyzer (Model 1000-RS, Advanced Micro Instruments).

[0066] "CO2 absorption" and "O2 absorption" were calculated by the following equations.

[0067] CO2 removal (m 3 / kg) = CO2 gas flow rate (m 3 / h)×CO2 gas flow time (h)×CO2 concentration 30ppm / removal agent weight (kg)

[0068] O2 removal (m 3 / kg) = O2 gas flow rate (m 3 / h)×O2 gas flow time (h)×O2 concentration 200ppm / removal agent weight (kg)

[0069] The results are shown in Table 1 below. In Examples (EX.) 1 and 2, CO2 removal was sufficient to exceed 1.6×10 -3 m 3 / kg, and O2 removal is sufficient to exceed 20×10 -3 m 3 / kg. In Comparative Example (Com.Ex.) 1, O2 removal was insufficient at 14×10 -3 m 3 / kg.

[0070] [Table 1]

[0071]

Claims

1. A method for removing CO2 and O2 from air, comprising the following steps: Place CO2 and O2 removers in containers. wherein the CO2 and O2 remover comprises 65 to 85 weight percent (wt.%) of nickel oxide (NiO), 5 to 20 wt.% of magnesium oxide (MgO) and 5.9 to 18.3 wt.% of Al2O3, wherein the weight ratio of nickel oxide to magnesium oxide (NiO / MgO) is 4 to 11, and wherein the wt.% is based on the weight of the CO2 and O2 removal agent; and Allow air to flow through the container.

2. The method according to claim 1, wherein the CO2 / O2 removal agent further comprises one or more other metal oxides selected from silicon oxide (SiO2), alkali metal oxides and mixtures thereof.

3. The method according to claim 1, wherein the CO2 and O2 removing agent further comprises 1 to 20 wt. % of silicon oxide (SiO2) based on the weight of the CO2 and O2 removing agent.

4. The method according to claim 1, wherein the CO2 and O2 removing agent further comprises 0 to 2 wt.% of an alkali metal oxide based on the weight of the CO2 and O2 removing agent.

5. The method of claim 1, wherein the CO2 and O2 removal agent does not contain alkali metal oxides.

6. The method according to claim 1, wherein the specific surface area (S BET ) is 10 to 1000m 2 / g.

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