Durable regenerable sorbent pellets for removal of hydrogen sulfide coal gas

A process for manufacturing durable sorbent pellets characterized by chemical and physical stability during multi-cycle sulfidation and regeneration reactions at temperatures above 260.degree. C. (500.degree. F.) consisting of forming a mixture of the following components:

• a material reactive with hydrogen sulfide and selected from the group consisting of oxides, acetates, formates, carbonates and nitrates of zinc, copper, iron, manganese, chromium, and a mixture thereof and having a particle size below 50 microns -30 to 65 weight percent;
• an inert material comprising varying size fractions and selected from the group consisting of silica, silica gel, alumina, alumina gel, drierite, zinc silicate, and sand wherein the particle size of said inert material is chosen to create additional voids between the components, thus increasing the porosity of the sorbent pellets -2 to 40 weight percent;
• a binder having a particle size less than said inert material, and selected from the group consisting of bentonite, kaolinite, cement, and mixtures thereof -2 to 60 weight percent;
• a diluent selected from the group consisting of calcium sulfate, calcium phosphate, and magnesium sulfate, -0 to 40 weight percent;
• a promoter selected from the group consisting of oxides or salts of copper, cobalt, manganese, nickel and mixtures thereof -0 to 10 weight percent;
• pelletizing the resulting mixture;
• drying the resulting pellets in vacuum;
• and
• calcining the dried pellets at a temperature above 371.degree. C. (700.degree. F.).