Optimization of bio-lube production using the automated fuzzy logic controlled temperature bioreactor and D-optimal design

Optimization of process parameters of many existing biolubricant were carried out based on the factor interactions and yield without putting the physicochemical properties into consideration. The aim of the work is to optimize the reaction temperature and time for the production of high-quality biolubricant using set objectives in relation to the physicochemical properties of the bio-lube produced. The reactor used consists of a reactor tank (2500 cm3 ), temperature, time, stirrer (agitation), speed ranged between 0 - 300oC, 0 - 120 minutes and 80 - 500 rpm respectively. The optimum temperature and time design matrix using Response Surface Methodology (Doptimal design) in Design Expert 11.0 software package. The results of the optimized yield of the castor seed oil biolubricant produced were compared with international standards for lubricant. The result shows better yield in the operational process of the fuzzy logic-controlled reactor. The yield of biolubricant for the experimental design matrix produced using the fuzzy logic reactor ranged between 79 - 96 %. Higher values were obtained from the study, except for the pour point values that were lower. The higher yield and the physical and thermal properties in castor oil biolubricant from the fuzzy logic temperature-controlled reactor could be as result of the uniform temperature and reaction time during the production process. The optimum condition for the bio-lube produced considering the optimum set goals for best quality biolubricant produced considering the set goal objective to comprise all the physico-thermal properties obtained in the study. The optimum condition was obtained at ninety-nine (99.5) minutes reaction time and 250oC reaction temperature with desirability value of 0.76. with the physico-thermal properties of 96.48 %, 33.7 mPa.s (33.7 cP), 15.5 mPa.s (15.5 cP), 179.9oC, 291oC, 15.9oC, for viscosity at 40oC, viscosity at 100oC, viscosity Index, Flash point, pour point. The physicochemical properties of biolubricant produced at optimum condition are within the recommended international standard. It can be concluded that the fuzzy logic-controlled reactor product is better biolubricant considering the number of parameters set goal to determine the optimum condition for production.