Catalytic performance of papermaking white clay in the transesterification of peanut oil with methanol

The catalytic performance of papermaking white clay in the transesterification of peanut oil with methanol was investigated in terms of catalyst quantity, molar ratio of methanol to oil, reaction temperature, and time. Meanwhile, the catalyst is characterized by thermogravimetric analysis, X-ray fluorescence, X-ray diffraction, nitrogen adsorption and Hammett indicator. After a sequence of pretreatments involving calcination at 800 ℃, hydration at room temperature and activation at 600 ℃, the catalyst mainly consists of calcium oxide, with surface area of 7.28 m²/g and basic strength of 9.8 < H_ < 15.0. The preferred conditions are catalyst percentage of 6%, methanol/oil molar ratio of 12 and reaction time of 2 h at 64 ℃; under these conditions, the transesterification efficiency reaches 90.74%. The catalyst from papermaking white clay exhibits good reusability; after being reused for six times, the transesterification efficiency remains above 88.63% under the preferred condition.