Supported heteropolyacids: Sytnhesis,characterization and effect of supports on esterification reactions

12-Tungstophosphoric acid supported onto silica was synthesized by impregnation. The supports and synthesized catalysts were characterized for chemical stability, ion exchange capacity, thermogravimetric analysis, differential scanning calorimetry, FT-IR, and BET surface area. The catalytic activity was evaluated for liquid phase esterification reactions. The catalyst was regenerated and reused. The best catalyst was calcined at different temperatures and its catalytic activity was also evaluated for esterification reactions under optimized conditions. Further, obtained results are compared with l2-tungstophosphoric acid supported onto zirconia in order to see effect of acidic nature of support on catalytic activity as well as thermal stability of the catalyst.