Production of novel applicable derivatives from biodiesel glycerin

Abstract

Glycerin (glycerol) is a co-product of biodiesel production that is widely produced and is available at a low cost. To date, various applications have been investigated and introduced for biodiesel glycerin. In this study, a number of valuable products were produced using biodiesel glycerin and formic acid as the main reactants. Allyl alcohol is one of the valuable chemicals produced from glycerin monoformate. Efficient production of this product requires successful completion of the first section of the reaction, which is an equilibrium reaction. The highest feasible yield achieved was about 83% (based on the consumption of formic acid) at 120-140°C without the addition of any catalysts. Also, the esterification reaction was further investigated at room temperature, where the equilibrium state was reached with a yield of 55% after only 4 h. Moreover, the addition of urea to the reaction with the aim of producing the other two side products, i.e. diformyl urea and glycerin carbonate, in addition to glycerin monoformate, was studied. The results showed that considerable amounts of applicable byproducts, e.g. formamid, are also produced, making the process even more economical.