role of water in the partial oxidation of propane to acrylic acid over mo1v0.3te0.23nb0.12ox catalyst

effects of water on the catalytic performances of movtenbo catalyst in the oxidation of propane to acrylic acid have been investigated at different reaction temperatures and different steam contents. obtained results show that both catalytic performances and catalyst structure are very sensitive to the presence of water vapor in the reaction feed. presence of water induces some structural modifications: improvement the crystallinity, decreasing production of non-selective sites and enhanced presence of the orthorhombic (m1) phase leading to better acrylic acid selectivity. moreover, the number as well as strength of the acid sites detected after reaction in water-present condition is lower than those of the used one in dry condition.