CuO-CeO2/ZSM-5 composites for reactive adsorption of hydrogen sulphide at high temperature

The high-temperature H 2 S removal at 500–700 °C was conducted over CuO-CeO 2 /ZSM-5 composites prepared with sol-gel method. 7Cu3Ce/ZSM-5 partially reacting at 500 °C yielded Cu 7 S 4 and Cu 2 S. The major sulphidation products at 600 °C were Ce 2 O 2 S, Cu 2 S, CuS, and S. Sulphidation of 7Cu3Ce/ZSM-5 at 700 °C yielded Ce 2 S 3 , Cu 2 S, Cu 2 S, and S. Sulphidation of 7Cu3Ce/ZSM-5 with 20 % H 2 and 20 % CO generated the same products Ce 2 O 2 S, Cu 2 S, Cu 2 S, and S. Increase in the degree of crystallinity of 7Cu3Ce/ZSM-5 resulted in the decrease of sulphur capacity during the sulphidation and regeneration process. Experimental results showed that the activity of CuO improved by adding Ce; 7Cu3Ce/ZSM-5 performed the optimal sulphiation behaviour at 600 °C with sulphur capacity of 1429 μmol/g (micromoles of sulphur per gram) due to the synergy of CuO and CeO 2 . H 2 repressed sulphur removal, causing the reduction of sulphur capacity from 1429 to 1014 μmol/g. CO had little impact on sulphidation reaction; sulphur capacity only reduced from 1429 to 1221 μmol/g due to the presence of 20 % CO.