Industrial & Engineering Chemistry Research, Vol.36, No.12, 5425-5431, 1997
Enhancement of the SO2 Sorption Capacity of CuO/Gamma-Al2O3 Sorbent by an Alkali-Salt Promoter
Sulfation of the alkali-salt-promoted CuO/gamma-Al2O3 sorbent has been carried out in a thermogravimetric analyzer, and the thermal decomposition characteristics of the sorbent and alkali salt in Nz gas were determined by a differential thermal analyzer. An addition of alkali salt to the sorbent increases SO2 sorption and reduces the temperature range for bulk sulfation of the CuO/gamma-Al2O3 sorbent. The main product in sulfation of the LiCl-promoted sorbent above 450 degrees C is found to be Al-2(SO4)(3) by an X-ray diffractometer. The rank for sulfur removal capacity of alkali salts as additives in CUO/gamma-Al2O3 sorbent is found to be LiCl > LiBr approximate to NaCl > LiF approximate to KCl approximate to NaF. In the cycle test of sulfation-regeneration at 500 degrees C, SO2 removal capacities of LiCl- and NaCl-promoted sorbents are over 3 times than those of the promoter-free sorbent for up to 30 cycles.