Effect of Preparation Methods and Pluronic Template on the Catalytic Activity of Ca/SBA-15
نویسندگان
چکیده مقاله:
Two approaches for metal ion incorporation were employed to introduce Ca2+ into SBA-15; Direct Synthesis (DS) and Wet Impregnation (WI). The non-ionic template was removed by two different methods; calcination and solvent extraction. The obtained catalysts were characterized by means of X-Ray Powder Diffraction (XRD), Energy Dispersive X-ray (EDX), and FT-IR spectroscopy. The basicity was determined by using Hammett indicators and benzoic acid titration. The effects of synthesis methods and organic template on basicity and catalytic performance were studied in the transesterification of Canola oil with methanol. 1H NMR was used to analyze the products. The best results were obtained using catalysts which prepared by wet impregnation method. Furthermore, calcination is a better method of template removal. So calcined Ca/SBA-15 prepared by impregnation showed particularly the highest activity (conversion 84.2 %). Although dis catalyst has a limited reusability in the transesterification reaction.
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عنوان ژورنال
دوره 37 شماره 2
صفحات 53- 60
تاریخ انتشار 2018-04-01
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