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The influence of high content of MoO3 (32mol%) in V2O5–MoO3–P2O5 catalyst system supported on alumina, silica, HZSM-5 and modified clay was investigated for ammoxidation of 3-picoline. Unsupported VMPO catalyst and supported catalysts were prepared by incipient wet impregnation method keeping the mole ratio of V2O5–MoO3–P2O5 (1.00:3.27:0.14) constant. FT-IR spectra and X-ray diffractograms showed interaction among the active oxides and the support. The major phases identified were Mo4V6O25, Mo6V9O40 and MoV2O8. TG–DTA also showed the exothermic peaks indicating the formation of new compounds above 400°C. The physico-chemical properties of the catalysts were correlated with their activity and selectivity for ammoxidation of 3-picoline. The unsupported catalyst showed 96.0% selectivity whereas VMPO/HZSM-5 showed the highest selectivity (91.3%) amongst the supported catalysts. [Copyright &y& Elsevier]

Catalytic conversion of methanol to hydrocarbons with the special emphasis on lower olefins (ethylene and propylene) was carried out using 12-heteropoly acids of W and Mo and P or Si and salts of 12-heteropoly acids. Amongst the metal salts of tungstophosphoric acid, cesium salt exhibited better activity and selectivity for the formation of ethylene and propylene. The maximum selectivity for C2–C4 olefins was 60.7%. Physico-chemical characterization of the catalysts has been made by FTIR spectroscopy, XRD, DTA, acidity by n-butyl amine titration and surface area. Acidity and surface area of the catalysts influence the activity and selectivity for the olefins.Oligomerization of ethylene to higher olefins was carried out in liquid phase using TiCl4–Et3Al2Cl3, TiCl4–Et2AlCl, TiCl4–Et3Al and Ti(OBu)4–Et3Al2Cl3 catalyst systems. Among the catalysts tried, TiCl4 and Ti(OBu)4 based catalysts showed better activity and selectivity to alpha olefins in the range C4–C14. For vapour phase, HZSM-5, nickel salt supported on SAPO-5 molecular sieve, ZSM-5 and γ-alumina, heteropoly acid supported on ZSM-5 and potassium salt of tungstophosphoric acid were tested. The maximum selectivity of C4–C6 olefins was 10.0wt.% with HZSM-5 catalyst with a Si/Al ratio of 100. The selectivity for higher olefins was less than that obtained by liquid phase oligomerization of ethylene. [Copyright &y& Elsevier]