Adsorption Purification of Used Industrial Oil Using Natural Aluminosilicates

Abstract

The results of adsorption purification of used industrial oil in the presence of natural aluminosilicates, benton-ite and mordenite, are discussed. It was found that the maximum degree of purification was achieved in the presence of mordenite and reached 61.68 % at an oil, adsorbent ratio of 2.3 at a temperature of 70 °C. The da-ta of the structural-group analysis of the oil showed that the main share of the hydrocarbon components re-moved during purification is accounted for by highly condensed aromatic ones. The supposed reasons for the different adsorption activity of bentonite and mordenite samples were judged from the data of chemical, min-eralogical, textural, and IR spectroscopic analysis. Based on the results of the IR spectra of mordenite sam-ples, it was concluded that energetically active hydroxyl groups can be responsible for their increased adsorp-tion activity. The used oil before purification is characterized by a high cyclicity of the hydrocarbons which included in the composition (aromatic hydrocarbons account for 38 % of the total), while the oil subjected to adsorption purification with mordenite (M-50) mainly becomes free of aromatic rings (the proportion of aro-matic hydrocarbons decreases up to 19.6 %). This is a consequence of the high polarizability of aromatic hy-drocarbons, in which, compared with other oil components, a dipole moment is easily induced under the in-fluence of the electrostatic field of the adsorbent.