Selective rhenium recovery from spent reforming catalysts

Reforming catalysts (0.3% Pt, 0.3% Re) are used extensively in industry for the improvement of the octane number of fuels. After deactivation the catalysts are treated for the recovery of Pt and Re. The aim of this study was to simplify the conventional recovery process by the application of a slight alkali solution (NaHCO3) for the selective dissolution of Re. The process was tested in batch and packed column reactors with crushed and uncrushed catalyst extrudes. The influence on the reaction yield of NaHCO3 concentration, pH, temperature and space velocity was examined and the optimum conditions were determined. The Re dissolution process seemed to follow first-order kinetics, and the recovery yield was up to 97% for crushed and up to 87% for uncrushed catalyst samples.