Separation and Purification Technology, Vol.13, No.1, 65-77, 1998
Removal of trace sulfur dioxide from gas stream by regenerative sorption processes
This work compares the characteristics and SO2 removal capacity of four physical adsorbents (sillicalite, DAY zeolite, polymer and carbon) and a chemical adsorbent (CuO/gamma-Al2O3)prepared in our laboratory by a sol-gel process. SO2 sorption capacity and kinetics of CuO/gamma-Al2O3, silicalite and DAY zeolite were measured gravimetrically and compared with those of the polymer and carbon adsorbents reported in the literature. The sol-gel derived granular CuO/gamma-Al2O3 adsorbent has the characteristics of large surface area, high crush strength and attrition resistance, and good sulfation properties. Simulated SO2 breakthrough curves from a fixed-bed adsorber packed respectively with each of the five adsorbents are presented to examine the performance of these adsorbents for SO2 removal in the fixed-bed process. Among the four physical adsorbents silicalite exhibits the best properties in terms of adsorption capacity and breakthrough time. Simulated and experimental results show that a fixed-bed packed with a chemical adsorbent (CuO/gamma-Al2O3) is far more effective (with much longer breakthrough time) than that with a physical adsorbent (silicalite) for removal of trace SO2 from gas stream.