钙基固体碱催化剂用于花生油酯交换制备生物柴油

Solid base derived calcium as a catalyst for transesterification of peanut oil to produce biodiesel

将钙基固体碱催化剂CaO和CaO／MgO用于催化花生油与甲醇酯交换制备生物柴油，考察了催化剂的制备条件，优化了CaO和CaO／MgO催化花生油酯交换反应工艺。研究表明，利用廉价碳酸钙作为原料，在800～900℃下N2气氛中煅烧制备的CaO具有比较好的催化活性；而CaOJMgO催化剂比较适宜的制备条件是用22．6％的Ca（Ac）2溶液浸渍MgO载体1次，在600℃下煅烧。CaO／MgO在空气中存放易失去活性，需在800—900℃下N：气氛活化。CaO和CaO／MgO催化剂均可使花生油与甲醇的酯交换反应在醇油摩尔比12：1、催化剂用量2％、反应温度65℃、反应时间2h的条件下获得80％以上的酯交换转化率。与CaO相比，CaO／MgO催化剂具有较高的抗水性和抗酸性，以及较好的重复使用性。

CaO and CaO/MgO, which were kinds of solid base catalyst derived calcium, were prepared, and their catalytic activities for the transesterification of peanut oil with methanol to produce biodiesel were investigated. The CaO was derived from CaCO3 by calcinating at 800 -900 ℃ with N2. The CaO/ MgO solid base catalyst was prepared by impregnating MgO in solution containing 22.6% Ca（Ac）2 ,then calcinated at 600 ℃ . The catalytic activity of CaO/MgO would be lost when stored in air and must be acti- vated at 800 - 900 ℃ with N2. The results showed that the CaO and CaO/MgO had higher catalytic activ- ity for transesterification reaction, and the conversion of peanut oil reached over 80% after reaction for 2 h under the conditions of atmospheric pressure, 65 ℃ , molar ratio of methanol to oil 12： 1, and catalyst dosage 2% . Compared with CaO, CaO/MgO showed better resistance to acidity and water. The reused CaO/MgO had better catalytic activity than that of reused CaO.