Role of the process conditions on the sulphation and stability of a CuO/SBA-15 type SOx adsorbent in cycling operations

{SOx abatement is one of the major challenges for the industry with regards to the more stringent European regulations. Despite their good performance, current DeSOx technologies are energy-intensive and produce waste. Flue gas desulphurisation using SOx adsorbents thus is a viable alternative. However, the development of such a technology is still hampered by the adsorbent short lifetime within the wide range of conditions prevailing at the exhaust of combustion engines. In this work, a CuO/SBA-15 adsorbent was assessed as a SOx trap material under different sulphation conditions (temperature from 350 degrees C to 450 degrees C, gas composition (SO2: 250, 450 and 450 ppm; O-2: 150 vol%), GHSV from 18,000 to 110,000 h(-1) and sulphation time). The SO2 adsorption capacity of the adsorbent was greatly impacted by the temperature: the higher the temperature, the better the performance. Indeed, the dynamic adsorption capacity is equal to 31 mg(SO2)/g(ads), 37 mg(SO2)/g(ads) and 52 mg(SO2)/g(ads) at 350 degrees C, 400 degrees C and 450 degrees C respectively. Conversely, no significant changes in the SO2 dynamic adsorption capacity were observed whatever the SO2 and O-2 molar fractions in the adsorption gas stream. The GHSV appears as a very sensitive parameter since the higher this parameter, the worse the adsorbent performance (e.g. for GHSV of 25,000 h(-1)