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CN-120586817-B - Porous composite adsorbent with controllable modification of deep desulfurization and preparation method thereof

CN120586817BCN 120586817 BCN120586817 BCN 120586817BCN-120586817-B

Abstract

The invention belongs to the technical field of desulfurization adsorbent preparation, and particularly relates to a porous composite adsorbent with controllable modification of deep desulfurization and a preparation method thereof. The preparation method of the porous composite adsorbent comprises the steps of preparing molecular sieve raw powder, exchanging with ammonium salt and potassium salt to prepare a modified molecular sieve, impregnating the modified molecular sieve with impregnating solution containing a metal nickel compound and a metal copper compound to obtain an active metal loaded modified molecular sieve, modifying aluminum oxide with organic zinc to obtain zinc modified aluminum oxide, uniformly mixing the active metal loaded modified molecular sieve, the zinc modified aluminum oxide, an adhesive and a pore-expanding agent, kneading and forming to obtain an adsorbent blank, and sequentially drying, roasting, micro-activating, washing and reducing to obtain the porous composite adsorbent. The porous composite adsorbent prepared by the invention has large specific surface area, high selectivity and high sulfur capacity, can reduce the content of organic sulfur such as thiophene to below 10ppb, and has high activity after regeneration.

Inventors

  • ZHANG HENG
  • WU WENPEI
  • DENG SHIMENG
  • XU QINGHUA

Assignees

  • 烟台百川汇通科技有限公司

Dates

Publication Date
20260508
Application Date
20250606

Claims (10)

  1. 1. A preparation method of a deep desulfurization controllable modified porous composite adsorbent is characterized by comprising the following steps: (1) Synthesizing a molecular sieve raw powder from an aluminum source, a silicon source, alkali liquor and a mesoporous template agent by a hydrothermal method, exchanging the molecular sieve raw powder in a mixed solution of ammonium salt and potassium salt, and then drying and roasting to obtain a modified molecular sieve; (2) Dispersing a metal nickel compound and a metal copper compound into a dispersing agent to prepare an impregnating solution, and impregnating the modified molecular sieve with the prepared impregnating solution to obtain a modified molecular sieve loaded with active metals; (3) Mixing an aluminum source, an acid source, organic zinc and a precipitator to prepare slurry, and aging, washing and drying to obtain zinc modified alumina; (4) Uniformly mixing a modified molecular sieve loaded with active metal, zinc modified alumina, an adhesive, a pore-enlarging agent and deionized water, and kneading and forming to obtain an adsorbent blank; (5) Sequentially drying, roasting, micro-activating, washing and reducing the adsorbent blank to obtain a porous composite adsorbent; in the step (4), the adhesive is at least one of kaolin, montmorillonite and medical stone; In the step (5), the micro-activation is carried out by adopting a micro-activation solution, wherein the micro-activation solution is at least one of an ammonium carbonate solution, an ammonium bicarbonate solution, an ammonia water solution and a sodium bicarbonate solution.
  2. 2. The preparation method of the deep desulfurization controllably modified porous composite adsorbent according to claim 1, wherein in the step (1), when the molecular sieve raw powder is synthesized, the mass ratio of the aluminum source to the silicon source to the alkali liquor to the mesoporous template agent is 1 (1-150): (1-500): (0.01-20); Wherein the aluminum source is at least one of aluminum powder, sodium metaaluminate, aluminum trichloride, aluminum nitrate and aluminum sulfate octadecanoate; The silicon source is at least one of silicon dioxide, white carbon black, tetraethoxysilane and silica sol; The alkali liquor is sodium hydroxide solution; the mesoporous template agent is at least one of cetyltrimethylammonium bromide, hexamethylammonium bromide, cetyl dimethyl trimethoxy silicon-based propyl ammonium chloride, P123 and F127.
  3. 3. The preparation method of the deep desulfurization controllably modified porous composite adsorbent according to claim 1, wherein in the step (1), the mass ratio of the molecular sieve raw powder to the ammonium salt, the potassium salt and the deionized water is1 (0.05-30): 0.1-25): 10-300 based on the dry basis of the molecular sieve raw powder during the exchange; The ammonium salt is at least one of ammonium chloride, ammonium nitrate, ammonium sulfate and ammonium carbonate, the potassium salt is at least one of potassium chloride, potassium nitrate, potassium sulfate and potassium carbonate, and the ammonium salt and the potassium salt adopt the same anion type when in exchange.
  4. 4. The method for preparing the deep desulfurization controllably modified porous composite adsorbent according to claim 1, wherein in the step (1), the exchange temperature is 40-100 ℃, the exchange time is 0.5-6h, the roasting temperature is 300-650 ℃ and the roasting time is 1-8h.
  5. 5. The preparation method of the deep desulfurization controllably modified porous composite adsorbent according to claim 1, wherein in the step (2), the mass ratio of the metal nickel compound, the metal copper compound and the dispersing agent in the impregnating solution is 1 (0.1-2): 0.2-10; Wherein the metal nickel compound is at least one of nickel nitrate, nickel oxide, nickel hydroxide and nickel acetate; The metal copper compound is at least one of copper nitrate, copper oxide, anhydrous copper sulfate and copper chloride dihydrate; The dispersing agent is at least one of absolute ethyl alcohol, methanol, formaldehyde, triethanolamine and hydrochloric acid.
  6. 6. The method for preparing the deep desulfurization controllably modified porous composite adsorbent according to claim 1, wherein in the step (2), the mass ratio of the modified molecular sieve to the impregnating solution is 1 (0.1-5).
  7. 7. The preparation method of the deep desulfurization controllably modified porous composite adsorbent according to claim 1, wherein in the step (3), the mass ratio of the aluminum source, the acid source, the organic zinc and the precipitant in the slurry is 1 (0.05-15): 0.1-5): 0.01-5; Wherein the aluminum source is at least one of aluminum powder, sodium metaaluminate, aluminum trichloride, aluminum nitrate and aluminum sulfate octadecanoate; the acid source is at least one of hydrochloric acid, nitric acid, sulfuric acid, acetic acid and citric acid; the organic zinc is at least one of diethyl zinc, dimethyl zinc and zinc isooctanoate; the precipitant is at least one of ammonia water and urea.
  8. 8. The preparation method of the deep desulfurization controllably modified porous composite adsorbent according to claim 1, wherein in the step (4), the mass ratio of the modified molecular sieve loaded with active metal, the zinc modified alumina, the adhesive, the pore-expanding agent and the deionized water is (10-100): 1-25): 3-35): 1 (5-100); wherein the pore-expanding agent is at least one of methylcellulose, ethylene oxide and sodium alginate.
  9. 9. The method for preparing the deep desulfurization controllably modified porous composite adsorbent according to claim 1, wherein in the step (5), the drying temperature is 70-200 ℃ and the drying time is 4-24 hours; The roasting temperature is 400-650 ℃ and the roasting time is 1-8h; The concentration of the micro-activation solution adopted in the micro-activation is 0.1 to 10wt.%; The reducing atmosphere is that hydrogen with the concentration of 20-30% is introduced into argon, the reducing condition is that the total airspeed is 100-400h -1 , the temperature is 350-680 ℃ and the time is 0.5-4h.
  10. 10. A deep desulfurization controllably modified porous composite adsorbent prepared by the preparation method according to any one of claims 1 to 9, which is characterized by having a specific surface area of 250 to 800m 2 /g, a pore volume of 0.5 to 1.2cm 3 /g, an average pore diameter of 6 to 45nm, a bulk density of 0.35 to 0.85g/cm 3 , a supported active component Ni content of 0.01 to 15wt.%, a Cu content of 0.01 to 10wt.%, and a Zn content of 0.03 to 10wt.%.

Description

Porous composite adsorbent with controllable modification of deep desulfurization and preparation method thereof Technical Field The invention belongs to the technical field of desulfurization adsorbent preparation, and particularly relates to a porous composite adsorbent with controllable modification of deep desulfurization and a preparation method thereof. Background Petroleum fossil fuels produce a large amount of sulfides in industrial production, which pollute the natural environment and are harmful to the health of people, and thus removal of sulfides from petroleum fossil fuels or derivatives thereof is required. At present, common desulfurizing agents generally adopt molecular sieves, alumina and other porous materials as adsorbents, but noble metals are required to be loaded to achieve better desulfurizing effects. In addition, in the traditional desulfurization process, the thiol, thioether and disulfide in the sulfide have simple structure and are easy to remove, and thiophene, benzothiophene, dibenzothiophene and derivatives thereof and the like are difficult to remove due to the aromatic structure and large steric hindrance. Patent CN114433004A discloses a benzene desulfurizing agent and a preparation method and application thereof, wherein 13X molecular sieve raw powder, potassium salt and deionized water are mixed and subjected to ion exchange treatment to obtain a modified 13X molecular sieve, then 0.3-0.6% of ruthenium is loaded, and the mixture is kneaded with alumina for forming to obtain the benzene desulfurizing agent. The desulfurizing agent can reduce the total sulfur content to below 10ppb, has better desulfurizing effect, but the ruthenium metal has high price and the desulfurizing agent has higher cost. Patent CN115770545A discloses a desulfurization adsorbent, a preparation method and application thereof in deep desulfurization of benzene, wherein the mixed solution containing nickel and zinc is subjected to coprecipitation treatment with alkaline saline solution, then is added into aluminum source solution for mixing, and the desulfurization adsorbent is obtained after treatment under different process conditions, wherein the nickel content is 20-60%, the zinc content is 3-10% and the aluminum oxide content is 30-77%. The effective sulfur capacity of the adsorbent can exceed 1.0g thiophene/kg desulfurization adsorbent under the temperature condition that the airspeed is not lower than 2h -1 and is not higher than 60 ℃, the cost is reduced although the effective sulfur capacity is not high and the service life or annual yield is reduced although the effective sulfur capacity is not loaded with noble metals. The adsorption desulfurizing agent in the current market mostly has the problems of large particle size, limited specific surface area and pore volume, unable maximization of the number of metal active sites, high price and the like, so that the adsorption desulfurizing agent needs longer reaction time, larger consumption and higher cost to achieve better desulfurizing performance. Therefore, how to improve the performance of the desulfurization adsorbent and reduce the cost to obtain the aromatic compound with high purity is a problem to be solved at present. Disclosure of Invention Aiming at the defects of the prior art, the invention aims to provide a porous composite adsorbent with controllable modification of deep desulfurization, which has large specific surface area, high selectivity and high sulfur capacity, can reduce the content of organic sulfur such as thiophene to below 10ppb and has high activity after regeneration, and a preparation method thereof The preparation method of the deep desulfurization controllably modified porous composite adsorbent comprises the following steps: (1) Synthesizing a molecular sieve raw powder from an aluminum source, a silicon source, alkali liquor and a mesoporous template agent by a hydrothermal method, exchanging the molecular sieve raw powder in a mixed solution of ammonium salt and potassium salt, and then drying and roasting to obtain a modified molecular sieve; (2) Dispersing a metal nickel compound and a metal copper compound into a dispersing agent to prepare an impregnating solution, and impregnating the modified molecular sieve with the prepared impregnating solution to obtain a modified molecular sieve loaded with active metals; (3) Mixing an aluminum source, an acid source, organic zinc and a precipitator to prepare slurry, and aging, washing and drying to obtain zinc modified alumina; (4) Uniformly mixing a modified molecular sieve loaded with active metal, zinc modified alumina, an adhesive, a pore-enlarging agent and deionized water, and kneading and forming to obtain an adsorbent blank; (5) And (3) sequentially drying, roasting, micro-activating, washing and reducing the adsorbent blank to obtain the porous composite adsorbent. In the step (1), when the molecular sieve raw powder is synthesized, the mass ratio of the