Partial hydrogenation of trimethylolpropane triester derived from sunflower seed oil over Pt/KIT-6 catalyst for high oxidation stability bio-transformer oil application

Currently, bio-transformer oil (BTO) is in high demand due to the increasing demand for electrical power and environmental policy considerations. Hence, this research aimed to produce BTO with high oxidation tolerance via partial hydrogenation of trimethylolpropane triester derived from sunflower seed oil (SF-TMPTE) over Pt/KIT-6 catalyst. The results revealed that as-prepared Pt/KIT-6 catalysts with various Pt loadings exhibited a high mesopore surface area with a uniform pore size distribution. The importance of studied reaction parameters on iodine value, reflecting the degree of unsaturation of hydrogenated BTO (H-BTO), was investigated using a univariate experiment and a 2k-factorial experimental design. The reaction condition was then optimized to obtain the H-BTO having the acceptable pour point (-10 °C) following IEC 62770 specification and high oxidation stability (14 h), which was the same levels as commercial BTO (FR3®). The obtained results indicated that the system operated using 0.25 wt% catalyst content consisting of 0.25 wt% Pt loading under 15 bar initial H2pressure and 1250 rpm stirring rate at 70 °C for 20 min was optimal to provide H-BTO having iodine value (IV) of 87 giodine/100goil, which reached the desired pour point and oxidation stability of -10 °C and 14 h, respectively. Additionally, the H-BTO obtained under this optimal condition exhibited physical and electrical properties that conformed to the IEC 62770 standard. The Pt/KIT-6 catalyst with an appropriate platinum loading also demonstrated excellent reusability, maintaining high performance over four consecutive cycles. This indicates that the production of H-BTO with high oxidation stability via catalytic hydrogenation over Pt/KIT-6 catalyst is a promising process with strong potential for future BTO manufacturing.