CuO-CeO2/ZSM-5 Composites for Reactive Adsorption of Hydrogen Sulphide at High Temperature

The high-temperature H2S removal at 500-700 degrees C was conducted over CuO-CeO2/ZSM-5 composites prepared with sol-gel method. 7Cu3Ce/ZSM-5 partially reacting at 500 degrees C yielded Cu7S4 and Cu2S. The major sulphidation products at 600 degrees C were Ce2O2S, Cu2S, CuS, and S. Sulphidation of 7Cu3Ce/ZSM-5 at 700 degrees C yielded Ce2S3, Cu2S, Cu2S, and S. Sulphidation of 7Cu3Ce/ZSM-5 with 20 % H-2 and 20 % CO generated the same products Ce2O2S, Cu2S, Cu2S, 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 degrees C with sulphur capacity of 1429 mu mol/g (micromoles of sulphur per gram) due to the synergy of CuO and CeO2. H-2 repressed sulphur removal, causing the reduction of sulphur capacity from 1429 to 1014 mu mol/g. CO had little impact on sulphidation reaction; sulphur capacity only reduced from 1429 to 1221 mu mol/g due to the presence of 20 % CO.