Catalytic method and apparatus for separating a gaseous component from an incoming gas stream
A process for separating at least a portion of an acid gas from a gaseous mixture, said process comprising contacting the gaseous mixture with an absorption medium and/or adsorption medium, wherein said medium absorbs and/or adsorbs at least a portion of the acid gas to form a rich medium; and separating at least a portion of the acid gas from the rich medium to form a lean medium; wherein the separation step is performed in the presence of an acid catalyst.
1. A process for separating at least a portion of an acid gas from a gaseous mixture, said process comprising:
a. contacting the gaseous mixture with an absorption medium wherein said medium absorbs at least a portion of the acid gas to form a rich medium; and
b. separating at least a portion of the acid gas from the rich medium to form a lean medium;
wherein the absorption step is performed in the presence of a heterogeneous alkaline catalyst and the separation step is performed in the presence of a heterogeneous proton donor acid catalyst, wherein the heterogeneous alkaline catalyst is not present in step b, and the heterogeneous proton acid donor catalyst is not present in step a,
wherein:
the acid gas is carbon dioxide; the absorption medium is an amine;
the heterogeneous proton donor acid catalyst is selected from heteropoly acids (HPAs), silica-supported Nafion (SAC-13), alumina, amorphous silica-alumina, molecular sieves, mesoporous aluminosilicates, clays, pillared clays (PILC), and acidic porous clay heterostructures (PCH), and combinations thereof; and the heterogeneous alkaline catalyst is selected from Na/NaOFi/AkCk, quaternary ammonium functionality supported over a resin (A26), quaternary ammonium salt functionalized silica gel, ZnO, ZrCh, Tl1O2, TiCk, CaO, MgO, MgCCk, SrO, BaO, Na metal dispersed on Al2O3, Na/MgO, La203, Y2O3, alkali metal oxides, alkali metal ions on alumina, alkali metal ions on silica, alkali metal on alkaline earth oxide, alkali metals and alkali metal hydroxides on alumina, basic clay minerals, KF supported on alumina and lanthanide imide and nitride on zeolite, and combinations thereof.
2. The process according to claim 1 , wherein the amine is selected from monoethanolamine (MEA), diglycolamine (DGA), diethanolamine (DEA), methyldiethanolamine (MDEA), 2-amino-2-methyl-1-propanol (AMP), and piperazine (PZ).
3. The process according to claim 1 , wherein the HPAs are selected from H 3 PW 12 O 40 and H 3 PMo 12 O 40 .
4. The process according to claim 1 , wherein the molecular sieves are selected from microporous aluminosilicates and zeolites.
5. The process according to claim 4 , wherein the zeolites are selected from HZSM-5, H—Y and H—X.
6. The process according to claim 1 , wherein the mesoporous aluminosilicates are selected from M41S aluminosilicates.
7. The process according to claim 6 , wherein the M41S aluminosilicates are selected from MCM-41, SBA-15 and MCF.
8. The process according to claim 1 , wherein the clays are selected from AlCl 3 /Al 2 O 3 , ZnCl 2 /Acid treated clays, FeCl 3 /graphite, SbF 5 /graphite, AlCl 3 /graphite, vanadium phosphates, aluminophosphates, CaO—ZrO 2 , Sm 2 O 3 —ZrO 2 , Yb 2 O 3 —ZrO 2 , aluminum chlorofluoride (ACF) and aluminum bromofluoride (ABF).
9. The process according to claim 8 , wherein the ACF is AlCl x F 3-x , wherein x≈0.05-0.25 and the ABF is AlBr x F 3-x , wherein x≈0.05-0.25.
10. The process according to claim 1 wherein the heterogeneous proton donor acid catalyst is HZSM-5.
11. The process according to claim 1 , wherein the heterogeneous alkaline catalyst is MgCO 3 .