Effect of additives on SO_2 sorption of CuO/gamma-Al_2O_3 sorbent

摘要

The sulfation of the alkali-salt promoted sorbent has been carried out in a thermogravimetric analyzer (TGA) and a differential thermoanalyzer (DTA). An addition of alkali-salt to the sorbent reduces the temperature range for bulk sulfation of CuO/gamma-Al_2O_3 sorbent and increase SO_2 sorption. The main product in sulfation of LiCl-promoted sorbent above 450 deg C is found to be Al_2(SO_4)_3. The rank of efficient alkali-salts as an additive in CuO/gamma-Al_2O_3 sorbent is LiCl>LiBr>NaCl>LiF on the basis of sulfur removal capacity. In the cycle test of sulfation-regeneration at 500 deg C, SO_2 removal capacity of NaCl-promoted sorbent is over 3 times than that of NaCl-free sorbent for up to 30 cycles.