Synthesis of O-propylated canola oil derivatives using Al-SBA-15 (10) catalyst and study on their application as fuel additive

Abstract

This research work provides insights on the application of Al-SBA-15 (10) as an efficient catalyst for the epoxide ring opening and O-propylation of unsaturated fatty acids in the canola oil and canola biodiesel. The objective of this study is to prepare potential lubricants from canola oil and canola biodiesel. The presence of unsaturation (>95%) in the oils is a limiting factor for a lubricant, and hence a two-step chemistry involving epoxidation followed by ring opening and O-alkylation has been employed to enhance the properties and make feedstocks promising as lubricants. Catalyst screening studies showed that Al-SBA-15 (10) catalyst is highly active in ring opening reactions with 1-propanol as a nucleophile. The physicochemical characterization showed that existence of Al3+ ions in Al-SBA-15 (10) promoted the desired transformation. Process optimization and statistical analysis were undertaken using CCD and RSM. Following are the optimal conditions at which 100% conversion of epoxidized oils to O-propylated biolubricants was achieved: temperature (100°C), epoxy to 1-propanol molar ratio (1:6), catalyst loading of 12% (w/w), and reaction time of 6h. A detailed investigation was presented in this article to optimize process conditions and to develop a plausible mechanism. Evaluation of physicochemical properties of O-propylated canola oil and O-propylated canola biodiesel showed their promising application as transmission gear oil and anti-wear hydraulic oils.