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以柠檬酸和金属盐为原料,采用有机凝胶先驱体转化法制备CaO/α-Fe中空纤维,通过XRD、SEM和VSM等技术对所得纤维进行了表征。结果表明:凝胶的可纺性与Ca2+:Fe3+:CA摩尔比有关,当Ca2+:Fe3+:CA为1:2:4.5时,可以得到可纺性好、钙含量较高的凝胶纤维,经1000℃还原焙烧后,制备的CaO/α-Fe中空纤维具有较大的长径比,直径可小于1μm,长度超过10cm,中空孔径约为纤维直径的2/3,在室温下的饱和磁化强度为136.564Am2/kg。考察了醇油摩尔比、催化剂用量、反应时间对转化率的影响,结果表明:当醇油摩尔比25:1、催化剂用量8%、反应时间为2.5h时,生物柴油的转化率在95%以上,催化剂重复使用15次生物柴油转化率仍无明显下降。
CaO / α-Fe hollow fiber was prepared by the precursor conversion method of organic gel using citric acid and metal salt as raw materials. The obtained fiber was characterized by XRD, SEM and VSM. The results show that the spinnability of the gel is related to the molar ratio of Ca2 +: Fe3 +: CA. When the Ca2 +: Fe3 +: CA is 1: 2: 4.5, the gellable fiber with good spinnability and high calcium content can be obtained. After calcined at 1000 ℃, the prepared CaO / α-Fe hollow fiber has larger aspect ratio, the diameter is less than 1μm, the length is more than 10cm, the hollow pore size is about 2/3 of the fiber diameter, the saturation magnetization 136.564 Am2 / kg. The results showed that when the molar ratio of alcohol to oil was 25: 1, the amount of catalyst was 8% and the reaction time was 2.5h, the conversion of biodiesel was 95% Above, there was still no obvious decrease in the biodiesel conversion rate after 15 times of catalyst re-use.