The preparation mechanism and anti-toxicity study on nanocrystalline Mg-Al hydrotalcite

Nano-crystalline Mg-Al hydrotalcite catalysts with different Mg/Al molar ratios were prepared.The effects of the catalysts on the transesterification of soybean oil to methanol were studied.The anti-water and anti-acid properties and the service life of the catalysts were confirmed and the preparation mechanism was researched.The results indicated that the reacting time of the transesterification reduced as the Mg/Al molar ratio of the catalysts increasing.The conversion rate of the methyl ester was up to 94.2% at Mg/Al molar ratio of 3.The service life of the catalysts was the longest at Mg/Al molar ratio of 4.The catalysts exhibited high anti-water and anti-acid properties,so it is unnecessary to dewater and deacidify soybean oil before the transesterification.