Hydrocracking of a coal extract with various catalysts

Catalytic hydrogenations using a number of bimetallic and monometallic catalysts were performed in an autoclave fitted with a falling/spinning catalyst basket. The catalysts were used as oxides with and without the addition of carbon disulphide to the autoclave charge. The products were separated by vacuum distillation and the performance of the catalysts was assessed by combining the yields from vacuum distillation with the peak area distribution of the gas chromatographs of the distillation fractions. The presence of carbon disulphide reduced the yield of material boiling below 260 °C and was particularly effective in reducing the yield of material boiling below 175 °C. Bimetallic catalysts which included molybdenum as one component generally performed better than similar bimetallic catalysts which included tungsten as one component and better than monometallic catalysts. Commercial CoMo performed well both with and without added carbon disulphide but commercial NiMo was inferior to most other catalysts when carbon disulphide was not added and to many when carbon disulphide was added. The sulphur content of the liquid products was not significantly affected by the addition of carbon disulphide to the charge.