Results of studies of the effect of a coagulant on the purification of used motor oils

The relevance of the problem of purification of used motor oils and their disposal is considered. Oil purification methods are presented and discussed. The choice of purification of used motor oil by the coagulation method is justified. Experiments were considered and carried out to select the most optimal coagulant. In order to determine the rational parameters of the sludge of used motor oils, a mathematical model of the dependence of the optical density of the settled oil after cleaning with a coagulant was obtained by calculation. This model made it possible to establish the dependence of optical density on settling time, settling temperature and on the percentage composition of the coagulant. After comparative tests, M1 (a solution of sulfuric acid and urea) was chosen as a rational coagulant. This is justified by its best coagulating reaction and the resulting purified motor oil increases several times. Based on these dependencies, a rational amount of coagulant M1 was determined: a percentage ratio of 3%, a settling time of 3-5 hours, and a settling temperature of 80°C.