Adsorbent materials, apparatus, and methods for removal of hydrogen sulfide from gases
An adsorbent composition, adsorbent apparatus, and gas purification process using the absorbent composition are provided for the removal of hydrogen sulfide from a gas containing at least hydrogen sulfide as an impurity. The adsorbent composition includes a combination of at least one carbon material, at least one clay material, and at least one metal oxide. In particular, the combination of carbon material(s), clay material(s) and metal oxide(s) provide for effective removal of hydrogen sulfide from a gas at a reduced cost.
1. An absorbent mixture for use in a gas purification apparatus having a flow path for a gas feed comprising:
an absorbent mixture for absorbing hydrogen sulfide from a gas feed, where the absorbent mixture comprises:
i. a first composition comprising a first metal oxide physically or chemically bonded to a surface of an activated carbon; and
ii. a second composition comprising a second metal oxide chemically or physically bonded to a surface of a macroporous clay having pores of diameters greater than 50 nm through which a gas comprising hydrogen sulfide can pass, and wherein the macroporous clay comprises a reaction surface area of about 400 m 2 /g or more;
where the absorbent mixture is configured to remove hydrogen sulfide from a gas feed flowing through a gas purification apparatus.
2. The absorbent mixture of claim 1 , wherein the first composition comprises from about 85% to about 97% of the activated carbon and from about 3% to about 15% of the first metal oxide.
3. The absorbent mixture of claim 1 , wherein the second composition comprises from about 95% to about 98% of the macroporous clay and from about 2% to about 5% of the second metal oxide.
4. The absorbent mixture of claim 1 , wherein the macroporous clay has a pore volume of from about 0.1 cm 3 /g to about 0.5 cm 3 /g.
5. The absorbent mixture of claim 1 , wherein the first or second metal oxide is an oxide of iron, magnesium, or calcium.
6. The absorbent mixture of claim 1 , wherein either or both of the first or second metal oxide is a combination of magnesium oxide and iron (Ill) oxide.
7. The absorbent mixture of claim 1 , wherein the first and second metal oxides are the same.
8. The absorbent mixture of claim 1 , wherein the first and second metal oxides are different.