School of Chemistry and Chemical Engineering, Henan University of Technology, Zhengzhou 450052, PR China.
Bioresour Technol. 2012 Sep;119:60-5. doi: 10.1016/j.biortech.2012.05.110. Epub 2012 May 30.
WO(3)/AlPO(4) catalysts were prepared by impregnation of AlPO(4) with ammonium metatungstate. Powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, and thermo gravimetric and differential thermal analysis (TG-DTA) demonstrated that the tungsten compound was incorporated into AlPO(4) forming the catalyst with an enhanced acidity. When transesterification of soybean oil over the catalysts was performed, the catalyst with 30 wt.% WO(3) loading and calcined at 1073 K, exhibited the best catalytic activity with a conversion of 72.5%. The transesterification was optimal at 453 K for 5h with a methanol/oil ratio of 30:1 and catalyst dosage of 5 wt.%. Free fatty acid (FFA) and water did not affect the catalytic activity. The catalyst proved to be stable over four transesterification cycles as it lost only 4% of its activity after being reused four times. The catalyst could be used for the transesterification of low-cost oils for biodiesel production.
WO(3)/AlPO(4) 催化剂是通过将 AlPO(4) 浸渍在偏钨酸铵中来制备的。粉末 X 射线衍射 (XRD)、傅里叶变换红外 (FT-IR) 光谱、热重和差热分析 (TG-DTA) 表明，钨化合物被掺入 AlPO(4) 中，形成了具有增强酸性的催化剂。当在催化剂上进行大豆油的酯交换反应时，负载 30wt.%WO(3)并在 1073K 下煅烧的催化剂表现出最佳的催化活性，转化率为 72.5%。在甲醇/油比为 30:1、催化剂用量为 5wt.%的条件下，在 453K 下反应 5h 时，酯交换反应最佳。游离脂肪酸 (FFA) 和水对催化活性没有影响。该催化剂在四个酯交换循环中表现出稳定性，重复使用四次后仅失去 4%的活性。该催化剂可用于低成本油脂的酯交换反应，以生产生物柴油。
