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

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7 h,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。

Synthesis of biodiesel by transition metal doped Fe/Zn double metal cyanide complex catalysts

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(II)-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.