Research of the process of receiving and preparing for to use of ecologically pure biofuel on the basis of tall oil

Abstract

The article discusses the scientific and technical issues of the methodology for producing liquid biofuel from renewable raw materials of plant origin. As raw materials used wastes from the production of pulp and paper mills — tall oil. The purpose of the work was to study the process of obtaining and determining ways to use the product. The optimal conditions for obtaining biodiesel are determined. The processing of raw materials was carried out by heating it with methanol in a ratio of 1:0,3 at a temperature of 50–65 °C for 2 hours in the presence of 2 % catalyst. The product, after separation of the resulting intermediate, was finally washed with water from the catalyst residues. The process was controlled spectrophotometrically. Using gas-liquid chromatography with mass spectrometric detection, the complete chemical composition of the used raw materials of various degrees of purification was established. It is shown that the main content in the processed oil is represented by natural lipids. Their fatty acid composition is described, comprising more than thirty C10–C24 fatty acids. A general scheme for producing biodiesel, which is a mixture of fatty acid alkyl esters, has been developed. The product was obtained by chemical transformation in the presence of acid catalysts, followed by the formation of fatty acid methyl esters. The component composition of the obtained product, biodiesel, was studied and it was shown that it consists of a mixture of methyl esters of fatty acids more than 95 %. In biodiesel, more than two hundred organic substances are also contained in the form of an insignificant amount of microimpurities. Their number fluctuated around 0,001 %. The basic physico-chemical characteristics of the obtained biodiesel are described in comparison with international requirements for biofuels. The analyzed product samples obtained from distilled TM, according to mass spectrometry, did not contain harmful impurities bromine, iodine, phosphorus and sulfur-substituted compounds. The total content of chlorine-substituted organic substances in all samples did not exceed 0,07 ± 0,02 %, and N-substituted derivatives did not exceed 0,05 ± 0,01 %, which indicates a rather high ecological purity of bitumen fuel. The main directions of the possible use of the product as liquid fuel for mini-boiler nozzles, as well as for operation in conventional diesel engines, are determined.