This paper deals with the synthesis of Sal oil methyl ester (SOME) biodiesel using Sal oil (Shorea robusta) and acidic ion-exchange resin catalyst (INDION-225 H). An experimental setup was proposed for the synthesis of SOME biodiesel where esterification of free fatty acids and transesterification of glycerides of fatty acids took place simultaneously with continuous removal of water. Effects of methanol and catalyst loading were studied to maximize the conversion of Sal oil to SOME biodiesel. Biodiesel productivity was also tested using recycled catalyst and a constant yield of biodiesel was obtained for all the catalyst recycle experiments. Scanning electron microscope (SEM) study of recycled catalyst was carried out to check the morphology of the catalyst and the degradation of the catalyst after recycling. SEM analysis revealed that the catalyst activity remained unchanged after several recycles. In the proposed process, ion-exchange resin not only reduced catalyst consumption and effluent generation considerably but also enhanced the productivity of SOME biodiesel considerably by eliminating the steps of purification. Acid value was measured continuously to monitor the extent of biodiesel formation with reaction time. The yield of SOME biodiesel was measured after purification of the reaction mass and it was tested using ASTM's standard methods of biodiesel testing. Finally, the properties of SOME biodiesel were compared with the petroleum-based diesel fuel.

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Industrially important di‐carboxylic acids are synthesized from mono‐carboxylic unsaturated and unsaturated fatty acids. In this study, the aim is to perform the simultaneous catalytic oxidative C=C cleavage of oleic acid (OA) to azelaic acid and pelargonic acid, and oxidation of the terminal methyl group in pelargonic acid to azelaic acid using cobalt‐ and manganese‐acetate as catalyst, hydrogen bromide as co‐catalyst and air in acetic acid at elevated pressure (2.8–5.8 barg) and temperature (353–383 K). Oxygen solubility is determined under varying pressure, temperature and OA loading. The effect of OA loading, pressure and temperature on OA conversion and azelaic acid selectivity is studied by varying one variable at a time; however, the presence of the synergistic effect of the catalyst and co‐catalyst is investigated by central composite design assisted response surface methodology. Oxidation of terminal methyl group in saturated fatty acid is also confirmed by the oxidation of stearic acid to octadecanedioic acid using identical oxidation conditions of OA. Oxidation products of fatty acids are quantified by gas chromatographic analysis. The innovation of the work is thus the ability of the catalytic system to perform a total oxidation of a terminal methyl group of the hydrocarbon chain. OA oxidation kinetics relating to catalyst and co‐catalyst concentration along with oxygen solubility at elevated temperature and pressure is established. The frequency factor and activation energy for OA oxidation is determined using the Arrhenius equation.