Effect of CsxH3−xPW12O40 addition on the catalytic performance of ZnFe2O4 in the oxidative dehydrogenation of n-butene to 1,3-butadiene

Oxidative dehydrogenation of n-butene to 1,3-butadiene over ZnFe2O4 catalyst mixed with CsxH3−xPW12O40 heteropolyacid (HPA) was performed in a continuous flow fixed-bed reactor. The effect of CsxH3−xPW12O40 addition on the catalytic performance of ZnFe2O4 was investigated. CsxH3−xPW12O40 itself showed very low catalytic performance in the oxidative dehydrogenation of n-butene. However, addition of small amount of CsxH3−xPW12O40 into ZnFe2O4 enhanced the catalytic performance of ZnFe2O4 catalyst. The catalytic performance of ZnFe2O4-CsxH3−xPW12O40 mixed catalysts was closely related to the surface acidity of CsxH3−xPW12O40. Among the catalysts tested, ZnFe2O4-Cs2.5H0.5 PW12O40 mixed catalyst showed the best catalytic performance. Strong acid strength and large surface acidity of Cs2.5H0.5PW12O40 was responsible for high catalytic performance of ZnFe2O4-Cs2.5H0.5PW12O40 mixed catalyst. Thus, Cs2.5H0.5PW12O40 could be utilized as an efficient promoter and diluent in formulating ZnFe2O4 catalyst for the oxidative dehydrogenation of n-butene.