Optimization of water and 1-pentanol concentrations in biodiesel-diesel blends for enhanced engine performance and environmental sustainability

This study focuses on optimizing the concentrations of water and 1-pentanol in biodiesel-diesel blends derived from Gossypium hirsutum (cottonseed) oil to enhance engine performance and reduce environmental impact. Biodiesel from cottonseed oil (COB) was produced via transesterification, followed by an analysis of its elemental and chemical composition, and physicochemical properties. Using a Box-Behnken design matrix, the volume concentrations of COB (10–30 %), water (5–15 %), and 1-pentanol (5–20 %) in diesel fuel were varied to optimize engine performance and emission characteristics. ANOVA was employed to evaluate the influence of these parameters on key output responses. The results demonstrated that COB possesses favorable elemental and chemical properties, and the optimal concentrations of COB, water, and 1-pentanol were identified as 14.7 %, 9.9 %, and 11.2 %, respectively. ANOVA findings revealed that COB had the maximum influence on brake specific fuel consumption (93.4 %), nitrogen oxides (55.3 %), carbon monoxide (78.5 %), and carbon dioxide (97.1 %), while 1-pentanol significantly influenced brake thermal efficiency (38.9 %) and hydrocarbon emissions (70 %). Confirmation experiments validated these optimizations, showing substantial improvements in both performance and emissions. The study concludes that integrating water and 1-pentanol into COB blends can reduce fossil fuel consumption by approximately 35 %, while enhancing energy efficiency and minimizing environmental impact.