Stabilized inorganic oxide supports and adsorbents derived therefrom for carbon dioxide capture

Patent metadata

Field	Value
Publication number	US-10112170-B2
Application number	US-201515124696-A
Country	US
Kind code	B2
Filing date	Jan 28, 2015
Priority date	Mar 14, 2014
Publication date	Oct 30, 2018
Grant date	Oct 30, 2018

Abstract

The present invention relates to a stabilized inorganic oxide support for capturing carbon dioxide from gases having high regeneration capacities over many cycles. The method for preparing the stabilized inorganic oxide support includes stabilizing an alumina-containing precursor by either calcining or steaming, impregnating an alkali or alkaline earth compound into the stabilized alumina-and drying the alkali or alkaline earth compound-impregnated stabilized alumina. The stabilized inorganic oxide support can be regenerated at lower temperatures between 100 and 150° C. The carbon dioxide adsorption capacity of the regenerated support is between 70 and 90% of the theoretical carbon dioxide adsorption capacity.

First claim

The invention claimed is:

1. A method for preparing an adsorbent for capturing carbon dioxide from gases, said method comprising the following steps:
a. stabilizing at least one alumina-containing precursor selected from the group consisting of gamma-alumina, silica-alumina, boebmite, pseudoboehmite and gibbsite by thermally treating said alumina-containing precursor to obtain a stabilized alumina-containing support, wherein the thermal treatment is carried out using at least one technique selected from the group consisting of calcination and steaming;
b. impregnating at least one alkali or alkaline earth compound into the stabilized alumina-containing support to obtain an alkali or alkaline earth compound-impregnated stabilized alumina-containing support, wherein the alkali or alkaline earth compound is at least one compound selected from the group consisting of alkali or alkaline earth carbonates, alkali or alkaline earth bicarbonates and alkali or alkaline earth oxides; and
c. drying the alkali or alkaline earth compound-impregnated stabilized alumina-containing support, wherein the step of drying is carried out at a temperature in the range of 80° C. to 140° C., preferably at 120° C., to obtain the adsorbent; wherein the amount of alkali or alkaline earth compound impregnated in the stabilized alumina-containing support ranges from 5 wt % to 60 wt % of the total weight of the adsorbent.

2. The method of claim 1 , wherein said stabilized alumina-containing support contains at least one alumina form selected from the group consisting of gamma, eta, theta, delta and alpha.

3. The method of claim 1 , wherein said alumina-containing precursor is subjected to a pre-step of impregnation with an alkali metal, before subjecting said alumina-containing precursor to thermal treatment for stabilization, said pre-step comprising:
treating said precursor with an alkali hydroxide, preferably sodium hydroxide, at a temperature in the range of 20 to 50° C., preferably 20 to 30° C., for a time period in the range of 10 to 20 min; and
drying said alkali hydroxide treated precursor in an oven for a time period in the range of 10 to 24 hours, preferably 12 hours, at a temperature in the range of 80 to 140° C., preferably at 120° C. to obtain an alkali metal impregnated alumina-containing precursor.

4. The method of claim 3 , wherein the thermal treatment of the dried alkali hydroxide treated alumina-containing precursor is carried out at a temperature in the range of 550 to 800° C.

5. The method of claim 1 , wherein the calcination is carried out at a temperature in the range of 550° C. to 1100° C., preferably in the range of 700° C., to 1100° C., more preferably in the range of 900° C. to 1100° C. in an oxidizing or inert environment.

6. The method of claim 1 , wherein the steaming is carried out at a temperature in the range of 550° C. to 900° C.

7. The method of claim 1 , wherein the alkali or alkaline earth compound is alkali carbonate, preferably, potassium carbonate (K 2 CO 3 ).

8. The method of claim 1 , wherein the amount of alkali or alkaline earth compound impregnated in the stabilized alumina-containing support ranges from 25 wt % to 40 wt %, the weights being expressed with respect to the total weight of the support.

9. The method of claim 1 , wherein the support has a surface area in the range of 170 to 550 m 2 /g; pore volume in the range of 0.18 cm 3 /g to 0.95 cm 3 /g; and pore size distribution in the range of 100 Å to 300 Å.

10. The method of claim 1 , wherein the support has a surface area in the range of 170 to 220 m 2 /g; pore volume in the range of 0.18 cm 3 /g to 0.95 cm 3 /g; and pore size distribution in the range of 150 Å to 200 Å.

11. The method of claim 1 , wherein the step of impregnating is carried out using a pore volume incipient wetness impregnation technique.

12. The method of claim 1 , wherein the support possesses carbon dioxide adsorption capacity in the range of 95% to 98% of the theoretical carbon dioxide adsorption capacity.

13. An adsorbent prepared by the method of claim 1 , wherein the adsorbent comprises;
i) stabilized alumina-containing support having surface area in the range of 170 to 550 m 2 /g; pore volume in the range of 0.18 cm 3 /g to 0.95 cm 3 /g; and pore size distribution in the range of 100 Å to 300 Å; and
ii) at least one alkali or alkaline earth metal precursor in an amount in the range of 5 to 60% based on the total weight of the adsorbent; wherein the at least one alkali or alkaline earth metal precursor is impregnated on the stabilized alumina-containing support;

wherein the fresh adsorption capacity of the adsorbent is at least 90% of the theoretical carbon dioxide adsorption capacity.

14. The adsorbent as claimed in claim 13 , wherein the stabilized alumina-containing support has a surface area in the range of 170 to 220 m 2 /g; pore volume in the range of 0.18 cm 3 /g to 0.95 cm 3 /g; and pore size distribution in the range of 100 Å to 300 Å.

15. The adsorbent as claimed claim 13 , wherein the stabilized alumina-containing support has a surface area in the range of 170 to 220 m 2 /g; pore volume in the range of 0.18 cm 3 /g to 0.95 cm 3 /g; and pore size distribution in the range of 150 Å to 200 Å.

16. The adsorbent as claimed claim 13 , wherein the stabilized alumina-containing support has total acidity in the range of 0.18 to 0.53 mmol of NH 3 /g.

Assignees

• Reliance Industries Ltd

Inventors

• Reddy Akuiri Satyanarayana
• Sengupta Surajit
• Dongara Rajeshwer
• Das Asit Kumar
• Amte Vinay
• Yadav Ashwani
• Bajpai Pramod Kumar
• Bhunia Haripada

Classifications

• Y02W10/33

  using wind energy · CPC title

• B01J20/08

  comprising aluminium oxide or hydroxide; comprising bauxite · CPC title

• B01D53/8681

  Acidic components (B01D53/8687 takes precedence) · CPC title

• B01J20/041 Primary

  Oxides or hydroxides · CPC title

• B01J20/2809

  Monomodal or narrow distribution, uniform pores · CPC title