Influence of drying and calcination temperatures for Ce-Cu-Al trimetallic composite catalyst on simultaneous removal H2S and PH3: Experimental and DFT studies.

This work explored the influences of the drying and calcination temperatures on a Ce-Cu-Al trimetallic composite catalyst for the simultaneous removal of H 2 S and PH 3. The effects of both temperatures on the structural features and activity were examined. The density functional theory method was used to calculate adsorption energies and further analyze their adsorption behavior on different slabs. Experiments revealed suitable drying and calcination temperatures to be 60 and 500°C, respectively. The capacity reached 323.8 and 288.1 mg/g. Adjusting drying temperature to 60°C is more inclined to form larger and structured grains of CuO. Rising calcinating temperature to 500°C could increase the grain size and redox capacity of CuO to promote performance. Higher temperatures would destroy the surface structure and lead to a crystal phase transformation, which was that the CuO and Al 2 O 3 were gradually recombined into CuAl 2 O 4 with a spinel structure. The exposed crystal planes of surficial CuO and CuAl 2 O 4 were determined according to characterization results. Calculation results showed that, compared with CuO (111), H 2 S and PH 3 have weaker adsorption strength on CuAl 2 O 4 (100) which is not conducive to their adsorption and removal. [Display omitted] [ABSTRACT FROM AUTHOR]