ISSN: 2277-9655 [Egbuna* et al., 5(10): October, 2016] Impact Factor: 4.116 IC™ Value: 3.00 CODEN: IJESS7 http: // www.ijesrt.com © International Journal of Engineering Sciences & Research Technology [105] IJESRT INTERNATIONAL JOURNAL OF ENGINEERING SCIENCES & RESEARCH TECHNOLOGY SUITABILITY OF SOYBEAN SEED OIL AS TRANSFORMER OIL Egbuna, S.O.*, Ude, O.C., Ude, C.N. * Department of Chemical Engineering, Enugu State University of Science and Technology (ESUT). Nigeria Research and Development Unit, Scientific Equipment Development Institute (SEDI) Enugu, Nigeria Engineering Research Development and Production Department, Project Development Institute (PRODA) Enugu, Nigeria DOI: 10.5281/zenodo.159296 ABSTRACT In search of solution to the harmful ecological problems due to toxicity and non-biodegradability posed by conventional transformer insulation oil (mineral oil), the production of transformer oil from soybean seed oil (vegetable oil) was carried out. The oil was extracted using n-hexane and was refined. The transformer oil was produced by transesterification and was characterized using American Society for Testing Material (ASTM) standard test. The solvent employed gave good yield of oil from the seeds. The result of characterization shows that the density is 0.940 (g ml–1), viscosity, 7.29 (cst), Flash Point 250oC, and dielectric strength of 21(KV) values, of Soybean seed oil as transformer oil produced under optimized conditions meet the ASTM standard and was within the acceptable limits as transformer oil. These showed that soybean seed oil is a potential feed stock for the production of transformer oil. KEYWORDS: Solvent Extraction, Biobased transformer oil, Soybean Oil, Trans-esterification, ASTM standard. INTRODUCTION Soybean (Glycin Max) originated in China. It is grown primarily for its protein content and secondary for oil. Seeds such as soybean seed with low oil content are better extracted using solvent extraction method. Soybean producers reportedly produce 22.7% oil and 45.5% protein on a dry weight basis [1]. Castor seed (Ricinus communi) is a specie that belongs to the Euphorbiaceae family. The common names are castor oil plant, and Palma Christi. It has its origin in Africa but can be found in tropical and subtropical countries of the world. The castor plant is drought-resistant and can thrive in arid conditions. It is non-edible as it contains ricin, a poisonous protein substance. The oil content of castor seed has been found to be between 46-55% by weight [2]. Often, the vegetable oils investigated for their suitability as bio-transformer oil are those which occur abundantly in the country of testing. The environmental properties of vegetable oils are excellent. Vegetable oils biodegrade quickly and completely, and also exhibit very low or no toxicity as compared to mineral oils. This is mainly due to the fact that vegetable oil dielectric fluids do not contain halogens, polynuclear aromatics, volatile or semi-volatile organics, or other compounds that can be present in mineral oils or other dielectric fluids [3]. Transformer oil or insulating oil is a highly refined mineral oil that is stable at high temperatures and has excellent electrical insulating properties. It is used in oil-filled transformers, some types of high voltage capacitors, fluorescent lamp ballasts, and some types of high voltage switches and circuit breakers [3]. Transformer oil produced from mineral oil is non-renewable, not volatile, and non-biodegradable. Transformers form an important part of an electrical network and it is the most expensive equipment in electrical Network. Without them, utility companies would not be able to transmit and distribute electricity generated at remote power stations [4]. Distribution transformer selection, whether for residential, commercial, industrial, or utility application, has long- term implications. Transformers can have lives of 15, 30, and even 50 years or more, depending on their design, loading, application, protection, and maintenance [3]. Because of the importance of the power transformers in electrical network, taking care of the oil quality is indispensable. The transformer oil, with the main roles of insulating and cooling in power transformers, is similar to the blood in human body and by monitoring its