Study of physical-chemical properties and catalytic activities of ZnCr2O4 spinel nano oxides obtained from different methods-Modeling the synthesis process by response surface methodology and optimization by genetic algorithm

作者：Hosseini S A^*; Alvarez Galvan M C

来源：Journal of the Taiwan Institute of Chemical Engineers, 2016, 61: 261-269.

DOI：10.1016/j.jtice.2015.12.024

• Zinc chromite
• Supported catalyst
• Nano-oxide
• Response surface design

Physicochemical properties of zinc chromite spinel obtained by sol-gel combustion, co-precipitation, and pechini methods were characterized by XRD, FTIR, SEM and TPR and studied as catalysts for the catalytic combustion of toluene. The sample obtained by pechini method showed the highest activity in the catalytic combustion of toluene. Supported zinc chromite samples based on ZSM-5 and gamma-Al2O3 were prepared by the pechini method with the ratio of spinel to support 2:1. Supported catalysts increased the rate of toluene conversion which is ascribed to a higher surface area and greater reducibility of zinc chromite in the supported catalysts. These factors also explain the better catalytic performance of ZnCr2O4/ZSM-5 compared than ZnCr2O4-Al2O3. The effects of synthesis factors on activity of catalysts were studied by response surface methodology. The model predicted that the relative importance of factors is as follows: calcination temperature > [citrate/nitrate ratio] > [citrate/EG ratio]. The optimization condition was predicted by genetic algorithm where the optimum conditions were resulted at levels-1, -1, and 0 of calcination temperature, [citrate/nitrate], and [citrate/EG], respectively.

• 出版日期2016-4