EFFECT OF MESOPOROUS RUTHENIUM CATALYSTS FOR HYDROGENATION OF PHENOL IN VAPOUR PHASE REACTOR

Abstract

The catalytic behaviour of RuO₂/SBA-15 was tested in order to cater the conversion of phenol to cyclohexanone in a fixed bed reactor. Mesoporous SBA-15 was synthesized by hydrothermal method. Different weight percentage (3, 5, 7 wt. %) of Ruthenia was loaded on SBA-15 by wet impregnation method. Physico-chemical characterization of material was meticulously evaluated by XRD, BET and FT-IR. The thermal stability of the catalyst was confirmed by TGA analysis. TPR results shows that the decomposition of RuO₂ to Ru at 300 °C. The oxidation state and chemical composition of the catalyst were identified by XPS analysis. The morphology of the catalyst was identified by using SEM and
HR-TEM with EDAX techniques. The catalytic activity was optimized by different parameter metrics by tweaking such as temperature, concentration of catalyst, the rate of flow of reactant etc with different iterations. Ruthenium oxide was also impregnated on carbon and alumina support (activated carbon and Al₂O₃ respectively) were also examined for hydrogenation reaction and then the results were compared with siliceous support. The maximum conversion of the phenol to cyclohexanone was achieved by passing 4 ml of phenol/h with flow rate of 50 ml of H₂/min (Sccm) on 5 wt.% at 350 °C using RuO₂/SBA-15 and was confirmed by GC. The lower selectivity of the cyclohexanone was found with a decrease in metal loading of RuO₂ on SBA-15.