Abukhadra Mostafa R, Basyouny Mohamed Gameel, El-Sherbeeny Ahmed M, El-Meligy Mohammed A, Luqman Monis
Geology Department, Faculty of Science, Beni-Suef University, Beni-Suef City 62511, Egypt.
Materials Technologies and Their Applications Lab, Geology Department, Faculty of Science, Beni-Suef University, Beni-Suef City 62511, Egypt.
ACS Omega. 2021 Jan 8;6(2):1556-1567. doi: 10.1021/acsomega.0c05371. eCollection 2021 Jan 19.
A CaO/clinoptilolite green nanocomposite (CaO/Clino) was synthesized by a green modification technique using calcium nitrate and green tea extract. The CaO/Clino nanocomposite promises a total basicity of 4.82 mmol OH/g, surface area of 252.4 m/g, and ion exchange capacity of 134.3 mequiv/100 g, which qualifies the product as an effective catalyst in the transesterification of castor oil. The transesterification performance of the CaO/Clino catalyst was addressed statistically based on the response surface methodology and central composite rotatable design, considering the essential experimental parameters. Based on the interaction effect between the studied variables, the CaO/Clino catalyst can achieve an experimental biodiesel yield of 93.8% after 2.5 h at 120 °C with 3.5 wt % catalyst loading and 15:1 ethanol/castor oil molar ratio. The optimization function of the design suggested enhancement in the performance of the CaO/Clino catalyst to achieve a yield of 95.4% if the test time interval increased to 2.65 h and the ethanol content increased to 16:1 as a molar ratio to castor oil. The produced biodiesel over CaO/ClinO has acceptable technical qualifications according to the international requirements (EN 14214 and ASTM D-6751). The synthetic green CaO/Clino nanocomposite has better recyclability as a heterogeneous catalyst and higher activity than some investigated catalysts in literature.
采用绿色改性技术，以硝酸钙和绿茶提取物为原料合成了一种CaO/斜发沸石绿色纳米复合材料（CaO/Clino）。CaO/Clino纳米复合材料的总碱度为4.82 mmol OH/g，比表面积为252.4 m/g，离子交换容量为134.3 mequiv/100 g，这使得该产品成为蓖麻油酯交换反应的有效催化剂。基于响应面法和中心复合旋转设计，考虑关键实验参数，对CaO/Clino催化剂的酯交换性能进行了统计分析。根据研究变量之间的相互作用效应，在120℃下，催化剂负载量为3.5 wt%，乙醇/蓖麻油摩尔比为15:1的条件下，CaO/Clino催化剂在2.5小时后可实现93.8%的实验生物柴油产率。设计的优化函数表明，如果测试时间间隔增加到2.65小时，乙醇含量增加到与蓖麻油的摩尔比为16:1，CaO/Clino催化剂的性能将得到提升，产率可达95.4%。根据国际要求（EN 14214和ASTM D-6751），在CaO/ClinO上生产的生物柴油具有可接受的技术指标。合成的绿色CaO/Clino纳米复合材料作为非均相催化剂具有更好的可回收性，并且比文献中研究的一些催化剂具有更高的活性。
