Effect of Carbon Monoxide on the Reaction of Hydrogen Sulfide and Calcium Oxide

Abstract

Experiments were conducted with simulated low Btu coal gas to focus on the effect of carbon monoxide on the rate of reaction of calcium oxide and hydrogen sulfide. No significant effect of carbon monoxide concentrations up to 35 percent by volume was noted. Other parameters of interest for high temperature desulfurization process development were varied. Within the predicted precision error of ±40 percent and the observed scatter due to sample variation, hydrogen concentrations from 10 to 40 percent by volume had no effect. The observed reaction rate was not affected by progressive conversion of part of the solid samples from calcium oxide to calcium sulfide. Data at 700°C were compared with data in the literature and agree well. The data at 700°C plus others at 600 and 800°C show a temperature variation consistent with a constant activation energy. At 700°C, the reaction rate for 0.389 mm geometric mean particle diameters over a broad range of simulated coal gas compositions is K (s−1) = 1.66 × 10−4 [H2S]0.85 for calcined dolomite and K (s−1) = 1.50 × 10−4 [H2S]1.00 for calcined calcium carbonate. [H2S] is in percent by volume and ranges from 0.1 to 5.0 percent.