02340nas a2200157   4500008004100000245013300041210006900174260000800243300001400251490000700265520171600272100002001988700002802008700002302036856012302059       2016                        eng d00aTemplate-free sol-gel synthesis of high surface area mesoporous silica based catalysts for esterification of di-carboxylic acids0 aTemplatefree solgel synthesis of high surface area mesoporous si  cOCT  a1247-12530 v193 aHigh surface area mesoporous silica based catalysts have been prepared by a simple hydrolysis/sol-gel process without using any organic template and hydrothermal treatment. A controlled hydrolysis of ethyl silicate-40, an industrial bulk chemical, as a silica precursor, resulted in the formation of very high surface area (719 m(2)/g) mesoporous (pore size 67 angstrom and pore volume 1.19 cc/g) silica. The formation of mesoporous silica has been correlated with the polymeric nature of the ethyl silicate-40 silica precursor which on hydrolysis and further condensation forms long chain silica species which hinders the formation of a close condensed structure thus creating larger pores resulting in the formation of high surface mesoporous silica. Ethyl silicate-40 was used further for preparing a solid acid catalyst by supporting molybdenum oxide nanoparticles on mesoporous silica by a simple hydrolysis sol gel synthesis procedure. The catalysts showed very high acidity as determined by NH3-TPD with the presence of Lewis as well as Brensted acidity. These catalysts showed very high catalytic activity for esterification: a typical acid catalyzed organic transformation of various mono- and di-carboxylic acids with a range of alcohols. The in situ formed silicomolybdic acid heteropoly-anion species during the catalytic reactions were found to be catalytically active species for these reactions. Ethyl silicate-40, an industrial bulk silica precursor, has shown a good potential for its use as a silica precursor for the preparation of mesoporous silica based heterogeneous catalysts on a larger scale at a lower cost. (C) 2016 Published by Elsevier Masson SAS on behalf of Academie des sciences.1 aMore, Pavan, M.1 aUmbarkar, Shubhangi, B.1 aDongare, Mohan, K.  uhttps://library.ncl.res.in/content/template-free-sol-gel-synthesis-high-surface-area-mesoporous-silica-based-catalysts