Zn(II) coordination polymer as a bifunctional catalyst for biodiesel production from soybean oil

Abstract

In this study, a Zn coordination polymer with formula [Zn(4,4′-bipy)(OAc)2]n, designated as compound 1 was prepared with Zn acetate and 4,4′-bipyridine in ethanol. It was characterized using X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, NH3 and CO2-TPD techniques. Compound 1 was found to be an efficient catalyst for biodiesel production. The effect of reaction parameters on the yield of fatty acid methyl esters (FAMEs or biodiesel) including the reaction temperature, time, molar ratios of methanol to oil and catalyst amount were investigated. Obtaining the highest biodiesel yield up to 98 % within 2 h in the presence of 2 % of compound 1 as catalyst (based on the soybean oil weight) together with its stability and reusability is promising. Due to insolubility of compound 1 in methanol and methyl esters, it can be easily separated and reused as catalyst. Therefore, the stability and reusability of 1 makes it a good alternative for biodiesel production.