Synthesis, characterisation and catalytic performance of HMCM-22 of different silica to alumina ratios

MCM-22 with different Si/Al ratios were synthesised using hexamethylenimine as the structure directing agent. The synthesised materials were characterised by XRD, BET, TGA, FT-IR, DRIFT and SEM techniques. The catalytic activity of the materials was examined in the vapour phase tert-butylation of phenol using tert-butyl alcohol as the alkylating agent. The influence of reaction parameters such as reaction temperature, reactant feed ratio, WHSV and time on stream was studied and the results are correlated with physicochemical characteristics of the catalysts. 4-tert-Butyl phenol (4-TBP) was obtained with high selectivity. It is presumed that the 10 membered ring channel present in MCM-22 might be the cause for selective production of 4-TBP.

The experimental results revealed that the workable range of Si/Al ratio for the synthesis of MCM-22 is 24–76. The catalytic activity of the materials was examined in the vapour phase tert-butylation of phenol using tert-butyl alcohol as the alkylating agent. The present investigation reveals the convenience in employing HMCM-22 for the selective production of 4-TBP in the tert-butylation of phenol. Figure optionsDownload as PowerPoint slide