Biodiesel stability under commercial storage conditions over one year

Results obtained from a long-term storage study using eleven different biodiesel samples are presented. Samples prepared from several feedstocks using different manufacturing technologies (with or without biodiesel distillation), some containing an antioxidant additive, were stored in 2001 drums. These were periodically monitored during the complete storage period by analysis of fifteen different properties. Several properties do not show any significant change during storage, while others such as viscosity, peroxide value and more dramatically, Rancimat Induction Period demonstrated changes related to the nature of the starting product. A parallel test, carried out in simulated wrong storage conditions (occasional shaking promoting intimate contact between biodiesel and air oxygen) lead to some strong changes in biodiesel composition and can be used as a guide for devising biodiesel production set-up, storage and distribution chain.