Biodiesel properties and automotive system compatibility issues

Acceptability of biodiesel by automotive sector is limited due to some of its adverse properties such as cold flow properties, oxidation stability and corrosiveness with automotive fuel system materials. Adverse cold flow properties of biodiesel lead to the problem of plugging and gumming of filters and injectors. There is a concern about the poor oxidation stability of biodiesel, which results in the formation of sediments and gums causing problem in the engine fuel injection system. Biodiesel reacts with automotive fuel system materials adversely resulting in corrosion of metals and degradation of elastomers. Beside these adverse issues, biodiesel possesses incredible inherent lubricity. This article aims to review the adverse biodiesel properties like cold flow properties, oxidation stability; corrosive and acidic nature resulting in non-compatibility with automotive fuel system materials. It also discusses the excellent lubrication behaviour of biodiesel and its positive impact. An effort has been made to present the review of 145 research papers along with the sharing of our some in-house experimental results. Additive treatment with biodiesel has been found to be suitable for improving the low temperature properties and oxidation stability. Certain metallic and elastomeric components have been reported as compatible/non-compatible with biodiesel. Although attempts have already been made by some researchers on the adverse properties of biodiesel but the scope is rather limited to the properties alone than correlating the same with automotive materials compatibility. (C) 2014 Elsevier Ltd. All rights reserved.