Study On The MoVTeNbO Catalysts For Propane Selective Oxidation To Acrylic Acid

Propane selective oxidation to acrylic acid （AA） has important social value andeconomic value. As the product of acrylic acid is chemically active, while the raw propane isstable, the biggest problem encountered by propane selective oxidation is that it is difficult toobtain high yield and maintain acrylic acid selectivity at the same time. Among the studiedcatalysts of propane selective oxidation to acrylic acid, multicomponent metal oxide （MMO）catalysts, which effect was the best, was studied latest. The MMO catalyst has multiplefunctions. By changing the composition, source, preparation method, it can change thecatalyst crystalline structure, acidic and redox properties. In this paper, according to thecharacteristics of selective oxidation of propane, combined with the published literature,patent, two kinds of MoVTeNbO catalysts were prepared using TeO₂and H₆TeO₆as differenttellurium source, and their structure and properties were studied by XRD, FTIR, SEM,TG-DTA, ICP, BET,TPR and TPD method to evaluate the catalysts performance of propaneselective oxidation. As the results showed:Using TeO₂as tellurium source, MoVTeNbO catalyst was prepared by slurry method.The effect of calcination conditions, hydration conditions and additives on the catalyst’scrystal structure, properties and the performance of selective oxidation of propane werestudied. As the results showed: calcination methods, calcination atmosphere and calcinationtime all have an effect on the crystal phase structure of the prepared catalyst and thus affectthe performance of propane selective oxidation. Proper hydration conditions can improve theconversion of propane and the selectivity of acrylic acid. Additives can change the catalystcrystalline structure, increase the catalyst surface area, but it is unfavorable for improving thecatalytic performance. We speculate that the catalysts performance for the selective oxidationof propane is the result of joint action of M1, M2two crystal phases.Using H₆TeO₆as tellurium source, MoVTeNbO catalyst was prepared by slurry method,the effects of process conditions, drying condition, additive Ni on catalytic performance werestudied. Choosing Al₂O₃as carrier, the catalyst was modified by kneading method. The resultsshowed that: suitable drying conditions can help to improve the performance of catalyst forselective oxidation of propane, reactor and catalyst loading quantity and technologicalconditions both have influence on the catalyst performance.