Abstract:
In the present study, metal-organic framework Cu-BTC-supported Sn (II)-substituted Keggin heteropoly nanocomposite (Sn1.5PW/Cu-BTC) was successfully prepared by a simple impregnation method and applied as a novel nanocatalyst for producing biodiesel from oleic acid (OA) through esterification. The nanocatalyst was characterized by Fourier transform infrared spectrometry (FTIR), wide-angle X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), nitrogen adsorption-desorption, thermogravimetrics (TG), and NH3-temperature-programmed desorption (NH3-TPD). Accordingly, the synthesized nanocatalyst with a Sn1.5PW/Cu-BTC weight ratio of 1 exhibited a relatively large specific surface area, appropriate pore size, and high acidity. Moreover, an OA conversion of 87.7% was achieved under optimum reaction conditions. The nanocatalyst was reused seven times, and the OA conversion remained at more than 80% after three uses. Kinetic study showed that the esterification reaction followed first-order kinetics, and the activation energy (E a ) was calculated to be 38.3 kJ/mol.
摘要:
在本研究中,通过简单的浸渍法成功制备了金属有机骨架Cu-BTC负载的Sn(II)取代的Keggin杂多纳米复合材料(Sn1.5PW/Cu-BTC),并将其用作由油酸生产生物柴油的新型纳米催化剂(OA)通过酯化。利用傅里叶变换红外光谱(FTIR)对纳米催化剂进行了表征,广角X射线衍射(XRD)扫描电子显微镜(SEM),透射电子显微镜(TEM),氮气吸附-解吸,热重(TG),和NH3程序升温脱附(NH3-TPD)。因此,合成的Sn1.5PW/Cu-BTC重量比为1的纳米催化剂表现出相对较大的比表面积,适当的孔径,酸度高。此外,在最佳反应条件下,OA转化率为87.7%。纳米催化剂被重复使用七次,3次使用后OA转化率保持在80%以上。动力学研究表明,酯化反应遵循一级动力学,活化能(Ea)计算为38.3kJ/mol。