Physicochemical properties of bio-based transformer oil synthesized via pretreated-epoxidized castor (Ricinus communis) seed oil followed by transesterification

Currently, bio-transformer oil is in high demand due to the increasing level of electrical power consumption and environmental policy. In this present study, bio-based transformer oil was synthesized from cold-extracted pretreated Castor seed oil. The physicochemical and electrical characteristics of the pretreated Castor seed bio-transformer oil (CSBO) revealed the saponification value (151 mg KOH g–1 oil), iodine value (88 g 100g–1 oil), acid value (0.02 mg KOH g–1 oil), viscosity at 27 ℃ (10.1 cSt), density at 29.5 °C (0.84 g/cm3), specific gravity at 20 ℃ (0.91), flash point (145 °C}, cloud point (10 °C), pour point (-9 °C), pH (5.7) and the dielectric strength (24 kV). The above values obtained for the bio-transformer oil were found to be within that of the American Standards for Testing Materials (ASTM D Standards), except that of dielectric strength, with a value less than one from the minimum ASTM D Standards recommended value. The Fourier Transform infrared (FT-IR) Spectroscopy results revealed the presence of the peak between 2800 cm–1 and 3000 cm–1 corresponding to the presence of the aliphatic groups (C–H stretching) in the synthesized CSBO and much more. Therefore, the refined/pretreated Castor seed oil can be used in place of the conventional transformer oil since it is easily biodegradable and safe for the environment due to its low acid content.