Agu C M, Agulanna A C, Kadurumba C H, Nnaji P C, Udokporo E L, Menkiti M C
Chemical Engineering Department, Michael Okpara University of Agriculture, Umudike, Nigeria.
Materials and Energy Technology Department, Projects Development Institute (PRODA), Emene Industrial Area, Enugu, Nigeria.
Heliyon. 2022 May 22;8(5):e09520. doi: 10.1016/j.heliyon.2022.e09520. eCollection 2022 May.
Epoxidation-esterification of fatty acid methyl ester obtained from kernel oil (IGKO), as well as its characterization, kinetics and thermodynamics were the main focus of this study. The methyl ester obtained via base catalyzed transesterification was used for epoxidation-esterification modification process. Epoxidation kinetics and thermodynamics parameters were also investigated. The properties of the IGKO and epoxidized-esterified kernel oil (IGKO) methyl ester (MIGKO) were determined using standard methods. Rate constant K and activation energy Ea for the epoxidation process was found to be of the order Lmols and 46.02 kJ/mol, respectively. ΔG, ΔH, and ΔS values for the epoxidation process were (94.74-101.42 kJ mol), 43.30 kJ mol, and 167.20 J mol K, respectively, indicating the non-spontaneous, endothermic, and endergonic nature of the process. The physicochemical characteristics of MIGKO were: 9 °C, 298 °C, 840 kg/dm, 13.84 mm/s, 1.351 mg KOH/g oil, 1.01 mg/kg and 39.78 kV, for pour point, flash point, density, viscosity, acid value, moisture content and dielectric strength, respectively. The MIGKO properties indicated its potential for use as a bio-transformer fluid, upon further treatment with pour point depressant.
从核油（IGKO）中获得的脂肪酸甲酯的环氧化-酯化及其表征、动力学和热力学是本研究的主要重点。通过碱催化酯交换反应得到的甲酯用于环氧化-酯化改性过程。还研究了环氧化动力学和热力学参数。使用标准方法测定了IGKO和环氧化酯化核油（IGKO）甲酯（MIGKO）的性能。发现环氧化过程的速率常数K和活化能Ea分别约为Lmol/s和46.02kJ/mol。环氧化过程的ΔG、ΔH和ΔS值分别为（94.74-101.42kJ/mol）、43.30kJ/mol和167.20J/(mol·K)，表明该过程是非自发的、吸热的和吸能的。MIGKO的物理化学特性分别为倾点9℃、闪点298℃、密度840kg/dm³、粘度13.84mm²/s、酸值1.351mg KOH/g油、水分含量1.01mg/kg和介电强度39.78kV。MIGKO的性能表明，在用降凝剂进一步处理后，它有潜力用作生物变压器油。
