Experimental and quantum chemical investigation of bio-fuels/lubricants for its oxidative stability

Abstract Vegetable oils have been showing promising results as raw materials for the formulation of bio-fuels and lubricants, but they possess poor oxidative stability. This study aims to investigate the effect of various herbal oils on the oxidative stability of vegetable oils. The present study used Karanja oil as a base oil with herbal oils such as Ginger, Turmeric, Holy Basil, Clove, Tinospora Cordifolia and Black Pepper oil. The experimental study optimised the concentration of herbal oils in Karanja oil. The viscosity increments and FTIR results of all the optimum combinations after 120 h of the hot oil oxidation test were evaluated. A detailed quantum chemical calculation was done using density functional theory to understand the oxidation mechanism. The quantum chemical descriptors of major anti-oxidative components were evaluated. Out of all the additives, 2% of holy basil oil in Karanja oil has shown better oxidative stability. The quantum chemical studies justified the experimental data.