Yingwei Li

Influence of acidic and basic properties of ZrO2 based catalysts on isosynthesis

Abstract Zirconium dioxide based catalysts were synthesized by mechanical mixing method and evaluated for the direct synthesis of isobutene and isobutane (i-C4) from CO hydrogenation. The experiments of temperature-programmed desorption of ammonia and carbon dioxide indicated that both the amount of acid–base sites and the strength of acid and base of the catalysts varied with the incorporation of promoters including various calcium salts, Al2O3 and KOH in ZrO2. The test results indicated that the activity and selectivity of the zirconia based catalysts depended on the acid–base properties of the catalysts. An appropriate amount of moderately strong acid–base sites and ratio of basic to acidic sites on the catalysts are significant for an active catalyst to selectively produce isobutene and isobutane from CO hydrogenation.

Influence of reactor materials on i-C4 synthesis from CO hydrogenation over ZrO2 based catalysts

Abstract The effect of reactor materials on the catalytic performance of the isosynthesis was investigated. Al 2 O 3 and several calcium salts promoted zirconium dioxide based catalysts were prepared by mechanical mixing method and evaluated in the isosynthesis reaction in a quartz lined stainless steel tubular reactor and a stainless steel tubular reactor, respectively. It was found that stainless steel tubular reactor seriously affected the selectivity of isosynthesis, while quartz lined stainless steel tubular reactor was favorable for the formation of i-C 4 hydrocarbons and suppressing the formation of CO 2 . The addition of Al 2 O 3 into ZrO 2 could largely enhance the activity while maintain the i-C 4 selectivity of pure ZrO 2 . CaF 2 or CaSO 4 as an additive promoted the formation of i-C 4 in the meantime maintain the activity of pure ZrO 2 . The influence of reaction temperatures on the catalytic performance of the catalysts in the quartz lined stainless steel tubular reactor was also investigated.