An environmentally benign method for the synthesis of heteropoly acids H3+nPMo12 nVnO40·xH2O (PMoVn, n = 1−3) was developed by the reaction of an aqueous slurry which contained stoichiometric amounts of MoO3, V2O5 and H3PO4. Characterization of the as-synthesized catalysts with inductively coupled plasma (ICP) elemental analysis, thermogravimetry (TG), X-ray diffraction (XRD) and infrared (IR) spectroscopy indicated that V ions substituted for Mo ions in Keggin-type phosphomolybdic acid. The as-synthesized samples were found to be an efficient catalyst for the hydroxylation of benzene which was carried out in a mixed solvent of acetonitrile and acetic acid with aqueous hydrogen peroxide as oxidant. PMoV2 exhibi ted the highest benzene conversion of 34.5% with phenol selectivity of 100%.
ZHANG Fumin, GUO Maiping, GE Hanqing, WANG Jun
. A new method for the synthesis of molybdovanadophosphoric heteropoly acids and their catalytic activities[J]. Frontiers of Chemical Science and Engineering, 2007
, 1(3)
: 296
-299
.
DOI: 10.1007/s11705-007-0054-0