(559e) Removal of Hydrogen Sulfide from Coal Gases, Using A Monolithic Catalyst Reactor

Removal of hydrogen sulfide (H₂S) from coal gases and sulfur
recovery as elemental sulfur are key steps in the development of advanced power
plants that employ coal and natural gas, and produce electric power and clean
transportation fuels.  The conventional method of sulfur removal and
recovery employing amine scrubbing, Claus, and tail-gas treatment involves a number
of steps and is energy intensive.  A novel process called Single-Step
Sulfur Recovery Process (SSRP) is under development at various research groups.
In this process, the H₂S in the coal gas is selectively oxidized in
a single step to elemental sulfur using sulfur dioxide (SO₂) or
oxygen (O₂) in the presence of alumina-based catalyst pellets in a
packed/fluidized bed.  

A monolithic catalyst reactor (MCR) for the development of a single-step
sulfur recovery process is used to remove H₂S from a simulated coal
gas in this study. Sulfur dioxide is used as an oxidizer to convert H₂S
into liquid element sulfur.  The monolith catalyst is wash-coated with
gamma alumina oxide. A performance of the monolithic catalyst is presented in
terms of H₂S removal capacity, deactivation, and selectivity of COS with various catalyst metal promoters at various reactor operation conditions.

The objectives
of this research are to formulate monolithic catalysts for removal of H₂S from coal gases and
minimum formation of COS with monolithic catalyst supports, gamma-alumina wash,
and catalytic metal promoters, to develop a catalytic regeneration method for a
deactivated monolithic catalyst, to
measure kinetics of both direct oxidation of H₂S to elemental sulfur with SO₂ as an oxidizer and selective formation of COSin the presence of a simulated coal gas mixture containing H₂, CO, CO₂, and moisture, using a monolithic
catalyst reactor.