A LONG LIFE ZINC-OXIDE-TITANIUM-OXIDE SORBENT

COAL-FIRED GASIFIER COMBINED CYCLES (GCC) HAVE BOTH HIGH EFFICIENCY AND VERY LOW EMISSIONS. A CRITICAL NEED FOR GCCS IS A METHOD OF REMOVING THE HYDROGEN SULFIDE (H2S) PRODUCED FROM THE SULFUR IN THE COAL FROM THE HOT GASES. THERE HAS BEEN EXTENSIVE RESEARCH ON HOT GAS CLEAN-UP SYSTEMS, FOCUSED ON THE USE OF A ZINC OXIDE BASED SORBENT (E.G., ZINC TITANATE). UNFORTUNATELY, CURRENT SORBENTS CAN BE USED FOR ONLY A FEW CYCLES BEFORE THEY EITHER LOOSE THEIR ACTIVITY OR FALL APART. A NEW METHOD HAS BEEN DEVELOPED FOR PRODUCING SORBENT PELLETS WITH GREATLY INCREASED LIFETIMES. WHEN USED WITH A TIN OXIDE SORBENT, THE PELLETS PRODUCED BY THE NEW METHODS HAVE AN ESTIMATED AVERAGE LIFETIME OF OVER 200 CYCLES UNDER HOT GAS CLEANUP CONDITIONS. THESE IMPROVED FABRICATION METHODS SHOULD BE DIRECTLY APPLICABLE TO THE PRODUCTION OF LONG LIFE, LOW COST SORBENTS CONTAINING ZINC OXIDE. THE PHASE I PROJECT AIMS TO DEMONSTRATE THAT THE PROCESS CAN BE ADAPTED TO THE LEADING SORBENT (ZNO), OPTIMIZE THE SORBENT COMPOSITIN, AND MEASURE CYCLIC LIFE.