Progress on compatibility issues of alcohols on automotive materials: Kinetics, challenges and future prospects- a comprehensive review

Alcohol could be the biggest factor in the improvement of the world biofuel economy in the present century due to its excellent properties on par with petroleum products. The biggest concern in the commercialization of alcohols is their material compatibility issues with various metals due to acidic form, moisture absorption and oxygenated nature. This review has been made to summarize the operational difficulties of alcohol for automotive applications. In the first phase of the review, the chemical kinetics of alcohols on corrosive formations has been outlined. In the second phase of the review, the effect of low carbon alcohols on various metals that were used in automotive engines and the compatibility issues were discussed in detail. Further, the study has been outlined microbiologically induced corrosion (MIC) of metals. Several limitations of alcohol usage with automotive engine components are highlighted and possible remedies are also recommended for corrosion reduction. In the end, special attention has been on various corrosive inhibitors for alcohol applications with a variety of materials. The properties like diffusion, acidity, conductivity and electro-potential are more dominant factors in corrosive formation. The comprehensive review shows that the oxygenated form and moisture absorption ability are the pivotal factors in the material compatibility of alcohols. The studies are also recommended that butanol has better anticorrosive qualities among all alcohols due to its less affection for water. Further, it is also identified that polymer-based materials and high-density polyethylene are the most appropriate materials for alcohol-based fuel supply systems and proper concentration of corrosion inhibitors with alcohols is of high importance for long-term application also. Several possibilities for the improvement of materials compatibility of all alcohols are also suggested. (c) 2022 Institution of Chemical Engineers. Published by Elsevier Ltd. All rights reserved.