The effect of reactor materials on the catalytic performance of the isosynthesis was investigated. Al2O3 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 CO2 The addition of Al2O3 into ZrO2 could largely enhance the activity while maintain the i-C-4 selectivity of pure ZrO2 CaF2 or CaSO4, as an additive promoted the formation Of i-C-4, in the meantime maintains the activity of pure ZrO2. The influence of reaction temperatures on the catalytic performance of the catalysts in the quartz-lined stainless-steel tubular reactor was also investigated. (C) 2003 Elsevier B.V. All rights reserved.