CN114433006A - Normal-temperature COS adsorbent and preparation method and application thereof - Google Patents

Normal-temperature COS adsorbent and preparation method and application thereof Download PDF

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CN114433006A
CN114433006A CN202011125887.9A CN202011125887A CN114433006A CN 114433006 A CN114433006 A CN 114433006A CN 202011125887 A CN202011125887 A CN 202011125887A CN 114433006 A CN114433006 A CN 114433006A
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adsorbent
cos
zinc
zinc oxide
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CN114433006B (en
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贾银娟
吴双
王灿
高焕新
杨贺勤
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China Petroleum and Chemical Corp
Sinopec Shanghai Research Institute of Petrochemical Technology
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China Petroleum and Chemical Corp
Sinopec Shanghai Research Institute of Petrochemical Technology
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    • C10G25/00—Refining of hydrocarbon oils in the absence of hydrogen, with solid sorbents
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    • C10K—PURIFYING OR MODIFYING THE CHEMICAL COMPOSITION OF COMBUSTIBLE GASES CONTAINING CARBON MONOXIDE
    • C10K1/00—Purifying combustible gases containing carbon monoxide
    • C10K1/002—Removal of contaminants
    • C10K1/003—Removal of contaminants of acid contaminants, e.g. acid gas removal
    • C10K1/004—Sulfur containing contaminants, e.g. hydrogen sulfide
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
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    • C10L3/00—Gaseous fuels; Natural gas; Synthetic natural gas obtained by processes not covered by subclass C10G, C10K; Liquefied petroleum gas
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    • B01D2253/25—Coated, impregnated or composite adsorbents
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    • B01D—SEPARATION
    • B01D2257/00—Components to be removed
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    • B01D2257/308—Carbonoxysulfide COS
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
    • C10G2300/00—Aspects relating to hydrocarbon processing covered by groups C10G1/00 - C10G99/00
    • C10G2300/20—Characteristics of the feedstock or the products
    • C10G2300/201—Impurities
    • C10G2300/202—Heteroatoms content, i.e. S, N, O, P

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Abstract

The invention relates to a normal-temperature COS adsorbent and a preparation method and application thereof, and mainly solves the problem that COS needs to be hydrolyzed into H in the prior art2S, H produced2S then passes through H2The process of S adsorbent removal is complex. The above-mentionedThe adsorbent comprises the following components in parts by weight: a) 1-10 parts of basic zinc carbonate; b) 30-80 parts of zinc oxide; c) 20-60 parts of alumina. The adsorbent can completely remove S impurities at normal temperature, and can be used for removing COS from natural gas, synthetic gas, light gas liquid hydrocarbons and the like.

Description

Normal-temperature COS adsorbent and preparation method and application thereof
Technical Field
The invention relates to a normal-temperature COS adsorbent and a preparation method and application thereof.
Background
Carbonyl sulfide (COS) and carbon disulfide (CS) exist in gas prepared by taking natural gas, coal, petroleum and the like as raw materials2) Iso-organic sulfur and hydrogen sulfide (H)2S) and the like. The current methods for removing organic sulfur can be divided into a wet method and a dry method. The wet method mainly comprises an organic amine solvent absorbent and a liquid catalytic hydrolysis conversion method. The investment and operation cost of the wet method is high, the power consumption is large, the operation is complex, and the requirement of fine desulfurization can not be met. The dry method mainly includes a hydroconversion method, an oxidation method, an adsorption method, a hydrolysis method and the like. Hydroconversion processes have certain side reactions. The oxidation method has high desulfurization efficiency, but the investment cost is high. The adsorption method is mainly used for high-precision H2The removal of S has high reaction temperature and side reaction. Compared with other methods, the method has the advantages that the energy consumption required by the hydrolysis method is obviously reduced, and the generation of byproducts can be effectively avoided in the low-temperature catalytic hydrolysis process, so that the method is the main method for removing COS at present. Removal of COS and CS by hydrolysis method2The process of (1) is as follows: COS on catalyst and H2O is hydrolyzed to generate a product H2S, then H2S is removed on a desulfurizing agent in the subsequent working section.
CN102600850B discloses a preparation method of an activated carbon-based catalyst capable of simultaneously removing carbonyl sulfide and carbon disulfide, which takes microwave activated carbon as a carrier and alkaline substances and metal oxides as active components to prepare the activated carbon-based catalyst capable of simultaneously removing carbonyl sulfide and carbon disulfide; the catalyst can be used for treating COS and CS in gas at the temperature of 30-90 DEG C2Simultaneously removing the by-products, simple process, convenient operation, low operation cost, COS and CS2High removal efficiency, COS and CS2The conversion rates of (A) were all greater than 90%.
CN108970611A discloses a natural gas organic sulfur hydrolysis catalyst and a preparation method thereof, wherein the catalyst takes three components of alumina, titanium oxide and white carbon black as carriers and takes sodium salt and cerium salt as active components. The specific surface area of the prepared catalyst is more than 300m2The volume of pores is 0.45ml/g, the activity stability is good, and the hydrolysis rate of organic sulfur is more than or equal to 99 percent. The invention adds titanium oxide as a carrier, has higher manufacturing cost, has the reaction temperature of 60 ℃, and can not meet the low-temperature use requirement.
CN1704145A discloses COS and CS2The hydrolysis catalyst adopts Al loaded with ammonium salt2O3The catalyst prepared by the method solves the problem that the existing desulfurizer can not remove organic sulfur with high precision, and has the advantage of high removal conversion rate.
CN101031350A discloses a catalyst prepared from a compound containing H2Process for the removal of COS from a synthesis gas stream of S and COS, the process comprising the step of (a) converting the COS in a first synthesis gas stream to H by contacting the first synthesis gas stream with a COS hydrolysis catalyst in the presence of water in a hydrolysis zone2S to obtain COS-poor and H-rich2A second syngas stream of S; (b) by reaction at H2Removing H from a second synthesis gas stream by contacting the second synthesis gas stream with a solid adsorbent in an S removal zone2S to obtain a lean H2S and a third syngas stream lean in COS.
The technologies realize the high-efficiency conversion of COS, but convert COS into H2S, then H is realized by other adsorbents2And (4) removing S.
Disclosure of Invention
The invention relates to a normal temperature COS adsorbent and a preparation method thereof, and mainly solves the problem that COS needs to be firstly hydrolyzed into H in the prior art2S, H produced2S then passes through H2The process of S adsorbent removal is complex.
In order to solve the above technical problems, a first aspect of the present invention provides a normal temperature COS adsorbent, which comprises, in parts by weight: a) 1-10 parts of basic zinc carbonate; b) 30-80 parts of zinc oxide; c) 20-60 parts of alumina.
In the technical scheme, the content of the basic zinc carbonate is preferably 3-8 parts by weight, the content of the zinc oxide is preferably 35-75 parts by weight, and the content of the aluminum oxide is preferably 25-55 parts by weight.
In the above technical scheme, the specific surface area of the adsorbent is as follows: 90-150 m2A/g, preferably 90 to 130m2(ii)/g; pore volume: 0.20-0.40 cm3Per g, preferably 0.20 to 0.35cm3/g。
In the technical scheme, the crystal grain of the zinc oxide is less than or equal to 15nm, preferably less than or equal to 12nm, and more preferably the crystal grain of the zinc oxide is 9-12 nm.
The second aspect of the present invention provides a method for preparing a normal temperature COS adsorbent, comprising the steps of:
(1) adding a solution I containing zinc and aluminum and an alkaline solution II into a reactor in a concurrent flow manner, keeping the pH value between 6 and 8, and reacting for 0.5 to 3 hours at the temperature of between 40 and 90 ℃ to obtain a mixed solution;
(2) adding pseudo-boehmite into the mixed solution, wherein the addition amount of the pseudo-boehmite is 20-30% of the mass of the zinc added in the step (1) and reacting for 0.25-1 hour to obtain a precursor A;
(3) roasting the basic zinc carbonate at 300-500 ℃ for 3-8 hours to obtain an active component B;
(4) and (3) mixing and pulverizing the precursor A obtained in the step (2), the active component B obtained in the step (3) and alumina into powder, kneading, molding and drying to obtain the COS adsorbent.
In the technical scheme, in the solution I containing zinc and aluminum in the step (1), the molar ratio is as follows: Zn/Al is 1.25-9; (Zn + Al)/H2O is 0.01 to 0.04. The zinc is preferably derived from zinc nitrate hexahydrate and the aluminium is preferably derived from aluminium nitrate nonahydrate.
In the above technical solution, the alkaline substance in the alkaline solution II in the step (1) is selected from one or more of sodium carbonate, sodium bicarbonate, and ammonium carbonate. Wherein the molar ratio of the alkaline substance to the water is 0.01-0.04.
In the technical scheme, the content of alumina in the pseudo-boehmite in the step (2) is 70-80%.
In the technical scheme, the step (1) of parallel-flow adding into the reactor is that bottom water is added into a coprecipitation reactor, the solution I is added into the coprecipitation reactor at a speed of 10-60 ml/min, and the solution II is added into the coprecipitation reactor at a certain speed, so that the pH value of the solution is kept between 6 and 8.
In the technical scheme, in the precursor A obtained in the step (2), the alkali-containing zinc carbonate accounts for 74-91% and the alumina accounts for 9-24% by mass.
In the above technical scheme, in the active component B in the step (3), the active component contains, by mass, 60% to 85% of zinc oxide, 15% to 40% of aluminum oxide, preferably 60% to 82% of zinc oxide, and 18% to 40% of aluminum oxide.
In the above technical solution, the alumina in the step (4) is any conventional alumina suitable for use as a binder. Step (4) adding HNO in the kneading process3. The drying is drying at 80-150 ℃.
The third aspect of the invention is to provide an application of the normal-temperature COS adsorbent in removing COS from natural gas, synthesis gas, coke oven gas and light gas liquid hydrocarbons.
The adsorbent of the invention obtains basic zinc carbonate by a coprecipitation mode, the basic zinc carbonate is mixed with zinc oxide synthesized by a coprecipitation precursor solid phase, the adsorbent has alkalinity, and partial COS is hydrolyzed into H2S is directly absorbed by ZnO of the adsorbent, and a part of COS reacts with the ZnO to generate ZnS so as to realize the direct removal of sulfur-containing impurities. Meanwhile, the auxiliary agent aluminum is introduced at different periods, and the aluminum is introduced for the first time when the zinc-containing solution is prepared, so that the reduction of zinc oxide grains can be brought, and meanwhile, the specific surface and the pore volume are also increased. And the auxiliary agent aluminum is introduced for the second time in the coprecipitation process, so that the comparative area and the pore volume of the adsorbent are further increased, and the sulfur capacity of the adsorbent is further improved.
Drawings
Fig. 1 is an XRD pattern of zinc oxide prepared in example 1.
Detailed Description
The present invention will be further described with reference to the following examples.
An XRD spectrogram: measured by an X-ray powder diffractometer of Japanese science model D/MAX-1400. Cu Kalpha line as ray source
Figure BDA0002733595800000031
And (3) scanning the nickel filter in a 2 theta scanning range of 5-70 degrees, operating voltage of 40KV, current of 40mA, and scanning speed of 10 degrees/min to obtain an XRD spectrogram. And calculating the grain size of the sample according to a Sherle formula by an XRD pattern.
The pore structure of the sample was measured using a surface analyzer model ASAP2600, the specific surface area was calculated by the BET method, and the total pore volume was calculated by the single point method.
[ example 1 ]
200ml of distilled water was added to a 2000ml coprecipitation reactor, a mixed solution of zinc nitrate having a concentration of 0.8mol/L and aluminum nitrate having a concentration of 0.2mol/L was added thereto at a rate of 20ml/min, and a 1.2mol/L sodium carbonate solution was added dropwise while maintaining a pH of 7, and the addition was carried out for 30 minutes, and after completion of the addition, the reaction was carried out at 60 ℃ for 1 hour to obtain a mixed solution. Then 7g of pseudo-boehmite is added into a coprecipitation reactor, the reaction is continued for 0.5 hour to obtain a precipitate, and the precipitate is washed and dried to obtain a precursor A containing the basic zinc carbonate (wherein the basic zinc carbonate contains 86.2 percent and the alumina contains 13.8 percent).
The precursor A is roasted for 5 hours at 400 ℃ to obtain the active component B containing zinc oxide (wherein, the active component B contains 74.7 percent of zinc oxide and 25.3 percent of alumina). Fig. 1 shows the XRD pattern of active component B, and the sample shows characteristic diffraction peaks of zinc oxide at 31.7 °, 34.4 °, and 36.2 °. And calculating the grain size of the zinc oxide to be 10nm by using a Scherrer formula according to the diffraction peak of the crystal face of the zinc oxide (100).
Mixing and powdering 5 parts of precursor A, 75 parts of active component B and 20 parts of alumina, adding 20 parts of 1.5% nitric acid, kneading and extruding into strips, and drying to obtain the COS adsorbent with the specific surface area of 110.9m2G, pore volume 0.27cm3(ii) in terms of/g. The product comprises the following components in parts by weight: 4.3 parts of basic zinc carbonate, 56.0 parts of zinc oxide and 39.7 parts of aluminum oxide.
5g of adsorbent is taken, and the space velocity is 1000h at normal temperature and normal pressure-1Inlet COS 1000ppm, outlet COS less than 0.5ppm, H2S less than 0.5ppm, COS treatmentThe amount (sulfur content) was 800 mg/g.
[ example 2 ]
200ml of distilled water was added to a 2000ml coprecipitation reactor, a mixed solution of zinc nitrate and aluminum nitrate was added at a rate of 20ml/min at a concentration of 0.7mol/L and 0.3mol/L, and a 1.2mol/L sodium carbonate solution was added dropwise while maintaining a pH of 7, and after the addition was completed, the reaction was carried out at 60 ℃ for 1 hour to obtain a mixed solution. Then 7g of pseudo-boehmite was added to the coprecipitation reactor, and the reaction was continued for 0.5 hour to obtain a precipitate, which was washed and dried to obtain a precursor A containing basic zinc carbonate (wherein the basic zinc carbonate contains 81.5% and the alumina contains 18.5%).
The precursor A is roasted at 400 ℃ for 5 hours to obtain an active component B containing zinc oxide (containing 67.6 percent of zinc oxide and 32.4 percent of alumina), and the zinc oxide crystal grain size is calculated to be 10 nm.
Mixing and powdering 5 parts of precursor A, 75 parts of active component B and 20 parts of alumina, adding 20 parts of 1.5% nitric acid, kneading and extruding into strips, and drying to obtain the COS adsorbent with the specific surface area of 122.5m2G, pore volume 0.35cm3(ii) in terms of/g. The product comprises the following components in parts by weight: 4.1 parts of basic zinc carbonate, 50.7 parts of zinc oxide and 45.2 parts of aluminum oxide.
5g of adsorbent is taken, and the space velocity is 1000h at normal temperature and normal pressure-1Inlet COS 1000ppm, outlet COS less than 0.5ppm, H2S is less than 0.5ppm, and the COS treatment capacity is 900 mg/g.
[ example 3 ]
Adding 200ml of distilled water into a coprecipitation reactor, adding a mixed solution of zinc nitrate with the concentration of 0.6mol/L and aluminum nitrate with the concentration of 0.4mol/L at the speed of 20ml/min, simultaneously dropwise adding a sodium carbonate solution with the concentration of 1.2mol/L, keeping the pH value at 7, adding for 30 minutes, and reacting for 1 hour at 60 ℃ after the completion of the addition to obtain a mixed solution. Then 7g of pseudo-boehmite was added to the coprecipitation reactor, the reaction was continued for 0.5 hour to obtain a precipitate, and the precipitate was washed and dried to obtain a precursor a containing basic zinc carbonate (wherein the basic zinc carbonate contains 76.1% and the alumina contains 23.9%).
The precursor A is roasted at 400 ℃ for 5 hours to obtain an active component B containing zinc oxide (containing 60.1 percent of zinc oxide and 39.9 percent of alumina), and the zinc oxide crystal grain size is calculated to be 10 nm.
Mixing and powdering 5 parts of precursor A, 75 parts of active component B and 20 parts of alumina, adding 20 parts of 1.5% nitric acid, kneading and extruding into strips, and drying to obtain the COS adsorbent with the specific surface area of 108.5m2G, pore volume 0.27cm3(ii) in terms of/g. The product comprises the following components in parts by weight: 3.8 parts of basic zinc carbonate, 45.1 parts of zinc oxide and 51.1 parts of aluminum oxide.
5g of adsorbent is taken, and the space velocity is 1000h at normal temperature and normal pressure-1Inlet COS 1000ppm, outlet COS less than 0.5ppm, H2S is less than 0.5ppm, and the COS treatment capacity is 700 mg/g.
[ example 4 ]
100ml of distilled water was added to a coprecipitation reactor, a mixed solution of 0.9mol/L zinc nitrate and 0.1mol/L aluminum nitrate was added at a rate of 20ml/min, and 0.6mol/L sodium carbonate solution was added dropwise while maintaining a pH of 6, and the mixture was added for 30 minutes, and after completion of the addition, the mixture was reacted at 90 ℃ for 0.5 hour to obtain a mixed solution. Then 7g of pseudo-boehmite is added into a coprecipitation reactor, the reaction is continued for 1 hour to obtain a precipitate, and the precipitate is washed and dried to obtain a precursor A containing the basic zinc carbonate (wherein the basic zinc carbonate contains 90.2 percent and the alumina contains 9.8 percent).
The precursor A is roasted at 500 ℃ for 5 hours to obtain an active component B containing zinc oxide (containing 81.3 percent of zinc oxide and 18.7 percent of alumina), and the zinc oxide crystal grain size is calculated to be 12 nm.
Mixing and powdering 5 parts of precursor A, 75 parts of active component B and 20 parts of alumina, adding 20 parts of 1.5% nitric acid, kneading and extruding into strips, and drying to obtain the COS adsorbent with the specific surface area of 95m2G, pore volume 0.20cm3(ii) in terms of/g. The product comprises the following components in parts by weight: 4.5 parts of basic zinc carbonate, 60.9 parts of zinc oxide and 34.6 parts of aluminum oxide.
5g of adsorbent is taken, and the space velocity is 1000h at normal temperature and normal pressure-1Inlet COS 1000ppm, outlet COS less than 0.5ppm, H2S is less than 0.5ppm, and the COS treatment capacity is 710 mg/g.
[ example 5 ]
200ml of distilled water was added to a 2000ml coprecipitation reactor, a mixed solution of zinc nitrate having a concentration of 0.8mol/L and aluminum nitrate having a concentration of 0.2mol/L was added thereto at a rate of 20ml/min, and a 1.2mol/L sodium carbonate solution was added dropwise while maintaining a pH of 8, and the addition was carried out for 30 minutes, and after completion of the addition, the reaction was carried out at 50 ℃ for 3 hours to obtain a mixed solution. Then 7g of pseudo-boehmite is added into a coprecipitation reactor, the reaction is continued for 0.5 hour to obtain a precipitate, and the precipitate is washed and dried to obtain a precursor A containing the basic zinc carbonate (wherein the basic zinc carbonate contains 86.2 percent and the alumina contains 13.8 percent).
The precursor A was calcined at 300 ℃ for 5 hours to obtain an active component B containing zinc oxide (containing 74.7% of zinc oxide and 25.3% of alumina), and the zinc oxide crystal grain size was calculated to be 10 nm.
Mixing and powdering 11 parts of precursor A, 69 parts of active component B and 20 parts of alumina, adding 20 parts of 1.5% nitric acid, kneading and extruding into strips, and drying to obtain the COS adsorbent with the surface area of 110.9m2G, pore volume 0.27cm3(ii) in terms of/g. The product comprises the following components in parts by weight: 9.5 parts of basic zinc carbonate, 51.5 parts of zinc oxide and 39.0 parts of aluminum oxide.
5g of adsorbent is taken, and the space velocity is 1000h at normal temperature and normal pressure-1Inlet COS 1000ppm, outlet COS less than 0.5ppm, H2S is less than 0.5ppm, and the COS treatment capacity is 730 mg/g.
[ example 6 ]
200ml of distilled water was added to a 2000ml coprecipitation reactor, a mixed solution of zinc nitrate having a concentration of 0.8mol/L and aluminum nitrate having a concentration of 0.2mol/L was added thereto at a rate of 20ml/min, and a 1.2mol/L sodium carbonate solution was added dropwise while maintaining a pH of 7, and the addition was carried out for 30 minutes, and after completion of the addition, the reaction was carried out at 60 ℃ for 1 hour to obtain a mixed solution. Then 7g of pseudo-boehmite is added into a coprecipitation reactor, the reaction is continued for 0.5 hour to obtain a precipitate, and the precipitate is washed and dried to obtain a precursor A containing the basic zinc carbonate (wherein the basic zinc carbonate contains 86.2 percent and the alumina contains 13.8 percent).
The precursor A is roasted at 400 ℃ for 5 hours to obtain an active component B containing zinc oxide (containing 74.7 percent of zinc oxide and 25.3 percent of alumina), and the zinc oxide crystal grain size is calculated to be 10 nm.
Mixing and powdering 2 parts of precursor A, 78 parts of active component B and 20 parts of alumina, adding 20 parts of 1.5% nitric acid, kneading and extruding into strips, drying to obtain the COS adsorbent,specific surface area 110.9m2G, pore volume 0.27cm3(ii) in terms of/g. The product comprises the following components in parts by weight: 1.7 parts of basic zinc carbonate, 58.3 parts of zinc oxide and 40.0 parts of aluminum oxide.
5g of adsorbent is taken, and the space velocity is 1000h at normal temperature and normal pressure-1Inlet COS 1000ppm, outlet COS less than 0.5ppm, H2S is less than 0.5ppm, and the COS treatment capacity is 720 mg/g.
[ example 7 ]
200ml of distilled water was added to a 2000ml coprecipitation reactor, a mixed solution of zinc nitrate having a concentration of 0.8mol/L and aluminum nitrate having a concentration of 0.2mol/L was added thereto at a rate of 20ml/min, and a 1.2mol/L sodium carbonate solution was added dropwise while maintaining a pH of 7, and the addition was carried out for 30 minutes, and after completion of the addition, the reaction was carried out at 60 ℃ for 1 hour to obtain a mixed solution. Then 7g of pseudo-boehmite is added into a coprecipitation reactor, the reaction is continued for 0.5 hour to obtain a precipitate, and the precipitate is washed and dried to obtain a precursor A containing the basic zinc carbonate (wherein the basic zinc carbonate contains 86.2 percent and the alumina contains 13.8 percent).
The precursor A is roasted at 400 ℃ for 5 hours to obtain an active component B containing zinc oxide (containing 74.7 percent of zinc oxide and 25.3 percent of alumina), and the zinc oxide crystal grain size is calculated to be 10 nm.
Mixing and powdering 10 parts of precursor A, 50 parts of active component B and 40 parts of alumina, adding 20 parts of 1.5% nitric acid, kneading and extruding into strips, and drying to obtain the COS adsorbent with the specific surface area of 130.9m2G, pore volume 0.35cm3(ii) in terms of/g. The product comprises the following components in parts by weight: 8.6 parts of basic zinc carbonate, 37.4 parts of zinc oxide and 54.0 parts of aluminum oxide.
5g of adsorbent is taken, and the space velocity is 1000h at normal temperature and normal pressure-1Inlet COS 1000ppm, outlet COS less than 0.5ppm, H2S is less than 0.5ppm, and COS treatment capacity is 690 mg/g.
[ example 8 ]
200ml of distilled water was added to a 2000ml coprecipitation reactor, a mixed solution of zinc nitrate having a concentration of 0.8mol/L and aluminum nitrate having a concentration of 0.2mol/L was added thereto at a rate of 20ml/min, and a 1.2mol/L sodium carbonate solution was added dropwise while maintaining a pH of 7, and the addition was carried out for 30 minutes, and after completion of the addition, the reaction was carried out at 60 ℃ for 1 hour to obtain a mixed solution. Then 7g of pseudo-boehmite is added into a coprecipitation reactor, the reaction is continued for 0.5 hour to obtain a precipitate, and the precipitate is washed and dried to obtain a precursor A containing the basic zinc carbonate (wherein the basic zinc carbonate contains 86.2 percent and the alumina contains 13.8 percent).
The above precursor was calcined at 400 ℃ for 5 hours to obtain an active component B containing zinc oxide (containing 74.7% of zinc oxide and 25.3% of alumina), the zinc oxide crystal grain size being calculated to be 10 nm.
Mixing 2 parts of precursor A, 97 parts of active component B and 1 part of alumina, pulverizing, adding 20 parts of 1.5% nitric acid, kneading, extruding, and drying to obtain COS adsorbent with specific surface area of 105.4m2G, pore volume 0.24cm3(ii) in terms of/g. The product comprises the following components in parts by weight: 1.0 part of basic zinc carbonate, 73.1 parts of zinc oxide and 25.9 parts of aluminum oxide.
5g of adsorbent is taken, and the space velocity is 1000h at normal temperature and normal pressure-1Inlet COS 1000ppm, outlet COS less than 0.5ppm, H2S is less than 0.5ppm, and the COS treatment capacity is 830 mg/g.
Comparative example 1
200ml of distilled water was charged into a 2000ml coprecipitation reactor, a 1.0mol/L zinc nitrate solution was added thereto at a rate of 20ml/min while dropping a 1.2mol/L sodium carbonate solution, the pH was maintained at 7, and the addition was carried out for 30 minutes, and after the completion of the addition, the reaction was carried out at 60 ℃ for 1 hour. And then adding 7g of pseudo-boehmite into the coprecipitation reactor, continuing to react for 0.5 hour to obtain a precipitate, and washing and drying the precipitate to obtain the basic zinc carbonate.
And roasting the precursor at 400 ℃ for 5 hours to obtain the zinc oxide with the grain size of 18nm.
Mixing 5 parts of basic zinc carbonate, 75 parts of zinc oxide and 20 parts of aluminum oxide, powdering, adding 20 parts of 1.5% nitric acid, kneading, extruding into strips, and drying to obtain the COS adsorbent with the specific surface area of 75.3m2G, pore volume 0.12cm3/g。
5g of adsorbent is taken, and the space velocity is 1000h at normal temperature and normal pressure-1Inlet COS 1000ppm, outlet COS less than 0.5ppm, H2S is less than 0.5ppm, and the COS treatment capacity is 600 mg/g.
Comparative example 2
Adding 200ml of distilled water into a 2000ml coprecipitation reactor, adding a mixed solution of zinc nitrate with the concentration of 0.8mol/L and aluminum nitrate with the concentration of 0.2mol/L at the speed of 20ml/min, simultaneously dropwise adding a sodium carbonate solution with the concentration of 1.2mol/L, keeping the pH value at 7, adding for 30 minutes, reacting at 60 ℃ for 1 hour after the completion of the addition, and washing and drying precipitates to obtain basic zinc carbonate.
And roasting the precursor at 400 ℃ for 5 hours to obtain the zinc oxide with the grain size of 11 nm.
Mixing 5 parts of basic zinc carbonate, 75 parts of zinc oxide and 20 parts of aluminum oxide, pulverizing into powder, adding 20 parts of 1.5% nitric acid, kneading, extruding into strips, and drying to obtain COS adsorbent with surface area of 80m2G, pore volume 0.19cm3/g。
5g of adsorbent is taken, and the space velocity is 1000h at normal temperature and normal pressure-1Inlet COS 1000ppm, outlet COS less than 0.5ppm, H2S is less than 0.5ppm, and the COS treatment capacity is 620 mg/g.
Comparative example 3
200ml of distilled water was added to a 2000ml coprecipitation reactor, a mixed solution of zinc nitrate having a concentration of 0.8mol/L and aluminum nitrate having a concentration of 0.2mol/L was added thereto at a rate of 20ml/min, and a 1.2mol/L sodium carbonate solution was added dropwise while maintaining a pH of 7, and the addition was carried out for 30 minutes, and after completion of the addition, the reaction was carried out at 60 ℃ for 1 hour to obtain a mixed solution. And then adding 7g of pseudo-boehmite into the coprecipitation reactor, continuing to react for 0.5 hour to obtain a precipitate, and washing and drying the precipitate to obtain a precursor A containing the basic zinc carbonate.
And roasting the precursor A at 400 ℃ for 5 hours to obtain an active component B containing zinc oxide, and calculating the zinc oxide crystal grain to be 10 nm.
Mixing 80 parts of zinc oxide and 20 parts of alumina, powdering, adding 20 parts of 1.5% nitric acid, kneading, extruding, and drying to obtain COS adsorbent with surface area of 110.9m2G, pore volume 0.27cm3/g。
5g of adsorbent is taken, and the space velocity is 1000h at normal temperature and normal pressure-1Inlet COS 1000ppm, outlet COS less than 0.5ppm, H2S is less than 0.5ppm, and the COS treatment capacity is 650 mg/g.

Claims (13)

1. The normal-temperature COS adsorbent is characterized by comprising the following components in parts by weight: a) 1-10 parts of basic zinc carbonate; b) 30-80 parts of zinc oxide; c) 20-60 parts of alumina.
2. The adsorbent of claim 1, wherein the basic zinc carbonate is present in an amount of 3 to 8 parts by weight, the zinc oxide is present in an amount of 35 to 75 parts by weight, and the aluminum oxide is present in an amount of 25 to 55 parts by weight.
3. The adsorbent according to claim 1, wherein the adsorbent has a specific surface area of 90 to 150m2A/g, preferably 90 to 130m2(ii)/g; the pore volume is 0.20-0.40 cm3Per g, preferably 0.20 to 0.35cm3/g。
4. The adsorbent according to any one of claims 1 to 3, wherein the crystal grains of zinc oxide are 15nm or less, preferably 12nm or less, and more preferably the crystal grains of zinc oxide are 9 to 12 nm.
5. A method for preparing the adsorbent according to any one of claims 1 to 4, comprising the steps of:
(1) adding a solution I containing zinc and aluminum and an alkaline solution II into a reactor in a concurrent flow manner, keeping the pH value between 6 and 8, and reacting for 0.5 to 3 hours at the temperature of between 40 and 90 ℃ to obtain a mixed solution;
(2) adding pseudo-boehmite into the mixed solution, wherein the addition amount of the pseudo-boehmite is 20-30% of the mass of the zinc added in the step (1), and reacting for 0.25-1 hour to obtain a precursor A;
(3) roasting the precursor A at 300-500 ℃ to obtain an active component B;
(4) and (3) mixing and pulverizing the precursor A obtained in the step (2), the active component B obtained in the step (3) and alumina into powder, kneading, molding and drying to obtain the COS adsorbent.
6. The preparation method according to claim 5, wherein in the zinc and aluminum-containing solution I of step (1), in terms of molar ratio: Zn/Al is 1.25-9; (Zn + Al)/H2O is 0.01 to 0.04.
7. The method according to claim 5, wherein the zinc in step (1) is derived from zinc nitrate hexahydrate and the aluminum is derived from aluminum nitrate nonahydrate.
8. The preparation method according to claim 5, wherein the mass fraction of alumina in the pseudo-boehmite in the step (2) is 70-80%.
9. The method according to claim 5, wherein the alkaline solution II in step (1) is one or more selected from sodium carbonate, sodium bicarbonate, and ammonium carbonate.
10. The method according to claim 9, wherein the molar ratio of the basic substance to water in the basic solution II is 0.01 to 0.04.
11. The preparation method according to claim 5, wherein the precursor A obtained in step (2) contains, in terms of mass fraction, 74% -91% of alkali-containing zinc carbonate and 9% -24% of alumina.
12. The preparation method according to claim 5, characterized in that in the active component B in the step (3), the zinc oxide is 60-85%, the aluminum oxide is 15-40%, preferably, the zinc oxide is 60-82%, and the aluminum oxide is 18-40% by weight.
13. Use of the adsorbent according to any one of claims 1 to 4 or the adsorbent prepared by the preparation method according to any one of claims 5 to 12 for removing COS from natural gas, synthesis gas, coke oven gas and light gas liquid hydrocarbons.
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