过渡金属掺杂亚铁锌双金属氰化物催化合成生物柴油的研究

摘要

Effects of transition metals ( La, Ce, Zr, Mn) on catalytic performance of double metal cyanide (DMC) catalysts for biodiesel synthesis were studied. The structure and performance of the catalysts were studied using XRD, FT-IR, ICP, BET et al. The experimental results showed that the DMC catalyst prepared by adding 1% of transition metal salts had higher activity. The catalyst with highest catalytic activity was prepared by adding 1 % of La( NO3) 3 ·nH2O. Under the conditions of methanol/oil mol ratio of 16 :1, catalyst amount of 2% and temperature of 160℃, a high yield (99.3% ) of fatty acid methyl esters (FAME) was obtained within 7 h. The analytical results showed that adding 1 % of transition metals did not change the molecular formula of Fe (Il)-Zn double metal cyanide complex catalysts, while it improved particle dispersion, decreased particle size and increased surface area. This was the reason that transition metals promoted catalysts had higher activity.%研究了掺杂过渡金属盐(La、Ce、Zr、Mn)对亚铁锌双金属氰化物(DMC)固体酸催化剂合成生物柴油的影响,并采用XRD、FT-IR、ICP、BET等方法对其进行结构和性能表征.结果表明,1％的镧、铈、锆、锰金属盐对催化剂的活性都有提高,其中,添加1％镧的DMC催化剂活性最高,在醇油摩尔比16∶1,反应温度160℃,催化剂加入量2％条件下,反应7h,脂肪酸甲酯收率达到99.3％.过渡金属盐引入对催化剂的组成没有影响,但使得催化剂更加分散,颗粒粒径更小,比表面积变大,有利于催化剂和反应物的接触,从而提高了催化剂活性.