Production of olefins via oxidative de-hydrogenation of C3-C4 fraction by CO2 over Cr-Mo/MCM-41

Scientific Essay from the year 2015 in the subject Chemistry - Other, , language: English, abstract: The present study investigates the oxidative de-hydrogenation of propane-butane (C3-C4) fraction over mono (Cr, Mo) and bi-metal (Cr-Mo) loaded MCM-41catalysts. The catalysts were prepared by sequential impregnation method at 500oC calcination temperature. Experiments were performed by feeding C3-C4 fraction and CO2 into a continuous flow quartz reactor at atmospheric pressure (P = 1 atm.), reaction temperatures between 500 - 650oC, gas hourly space velocity within 100 - 400 h-1, and at reaction time (tr) = 2h. The physicochemical properties and performance of catalysts were evaluated by BET, XRD, H2-TPR, and NH3-TPD characterization techniques. The major products are ethylene, propylene, isobutylene, butylene. This paper reports that the total yield of olefins (? C2-C4) = 71.6 % was achieved at 89.5 % conversion level of C3-C4 at 630oC. The results indicate that the addition of Mo to Cr/MCM-41 modifies its catalytic activity. The Cr/MCM-41 and Mo/MCM-41 catalysts were prepared for comparison purposes.