Development of a Method for Determination of Fatty-Acid Composition and Lower Heat of Combustion of Biodiesel Fuel

Abstract

The situation that has developed on the market of oil products in the conditions of the war with the invaders has led to a shortage of liquid fuels and a constant increase in the price, in particular of diesel fuel, prompting the producers of agricultural products to think about switching to alternative types of fuel. Research related to the production and use of biodiesel fuel is especially relevant in today's conditions. Scientists do not ignore this question, in particular, Vinnytsia National Agrarian University has devoted more than one research topic to the mentioned problem. In more detail, in the mentioned issue, research is being conducted aimed at determining the energy value of the obtained biofuels, namely, the lower calorific value. The purpose of the article is to create a methodology for determining the fatty acid composition of biodiesel fuel and determining its lower heat of combustion, which is necessary for the analysis and evaluation of the energy efficiency of alternative fuels. Research methods are based on D. I. Mendeleev's formula for determining the lower heat of combustion, which is based on data on the percentage content of the elemental composition of the fuel. The calculation of the elemental composition was carried out on the basis of the molecular weight data of the components of biodiesel fuel, which in turn were obtained by chromatographic analysis using a gas-liquid chromatograph. Similar calculations were made in Microsoft Excel spreadsheets. The article publishes the results of research on two samples of biodiesel fuel, made from two types of raw materials - sunflower and rapeseed oil. A method of determining the fatty acid composition of these samples and determining the lower heat of combustion of biodiesel fuel as a whole and its components has been developed. The results given in the tables can be the basis for further conclusions about the energy value of individual components included in the studied fuel.