A high-pressure coal gasification process development unit (PDU) has been used by the Institute of Gas Technology to study in-sim desulfurization in an ash-agglomerating, fluidiied-bed coal gasifier at elevated pressures. Previous work in this area has been limited to pressures up to about 225 psig. The current work extends this pressure range to 400 psig, well within the pressure range of the combustion turbines now being considered for application in integrated gasification combined cycle (IGCC) power plants. The coal used in this study was Pittsburgh No. 8 bituminous coal, and the sorbent used was New Enterprise limestone. Data were collected and analyzed to determine the effects of gasifier pressure and temperature on sulfur capture within the fluidized bed. The optimum temperature for maximum sulfur removal was determined as a function of the partial pressure of CO2in the fluidized bed.