Production of biodiesel from low-quality vegetable oils with a high content of free fatty acids by alkaline transesterification

Univesity of Ruse “Angel Kanchev”, Department of Repairing, Reliability, Mechanisms, Machines, Logistic and Chemical Technologies, Agrarian and Industrial Faculty, 7017 Ruse, Bulgaria

^* Corresponding author: vkopchev@uni-ruse.bg

Abstract

The extraction of natural fats as well as the production of derived products based on them are renewable processes that play a major role in the modern energy industry. An example in this regard is the so-called biodiesel fuel which is Fatty Acid Methyl Esters (FAME), the production of which in recent years has reached enormous scales. Its main advantage is that it is an ecological product (methyl ester of higher fatty acids), which before and after use does not pollute the environment. Quality biodiesel fuel, in turn, is obtained from quality raw materials, which invariably limits its production. On the other hand, every year as a result of improper storage or processing, as well as obtained as waste products huge amounts of low-quality oils remain unutilized and they in turn, represent a valuable raw material and source of energy after their conversion into biodiesel fuel. The present work investigates the possibility of obtaining methyl esters of fatty acids (biodiesel) from low-quality (bad-quality) vegetable oils with high acid values by transesterification with an alkaline catalyst, which includes the selection of suitable catalysts and conditions for the optimal course of the process.