Increasing use of renewable energies
Fuels from renewable vegetable sources have seen an impressive increase in use. Unlike fossil fuels, biogenic fuels reduce the accumulation of CO2 in the atmosphere and may slow down global warming. In addition, alternative fuels such as biodiesel are biodegradable and thus less environmentally harmful.
What is biodiesel?
Fatty acid methyl esters have gained considerable economic importance as alternative fuels. Also known as biodiesel or FAME (fatty acid methyl esters) they are usually obtained from oil seeds. In the transport sector they are mainly used in a mixture with conventional diesel, as so-called biodiesel blend.
Oxidation stability as a quality criterion for biodiesel
Transesterification of vegetable oils with methanol produces the methyl esters of the fatty acids (together with glycerol as a byproduct). These have only a limited shelf-life as they are slowly oxidized by atmospheric oxygen.
The resulting oxidation products can cause damage to combustion engines. This is why oxidation stability is an important quality criterion for biodiesel, which needs to be regularly determined during production. With the 893 Professional Biodiesel Rancimat this determination can be carried out quickly and simply. Oxidation can be delayed by adding antioxidants. The 893 Professional Biodiesel Rancimatcan also be used to determine the effectiveness of the antioxidants.
International Standards on biodiesel quality
The oxidation stability has become a standard parameter used to define the minimum quality requirements of biodiesel and biodiesel blends.
Specifications
- ASTM D 6751 (ASTM - American Society for Testing and Materials) «Standard specification for biodiesel fuel blend stock (B100) for middle distillate fuels»
- ASTM D 7467 (2009) «Standard Specification for Diesel Fuel Oil, Biodiesel Blend (B6 to B20)»
- EN 14214 (2008) «Automotive fuels - Fatty acid methyl esters (FAME) for diesel engines - Requirements and test methods»
- EN 14213 «Heating fuels - Fatty acid methyl esters (FAME) - Requirements and test methods»
- EN 590 (2009) « Automotive fuels - Diesel - Requirements and test methods»
Test methods
- EN 14112 «Fat and oil derivatives - Fatty acid methylesters (FAME) - Determination of oxidation stability (accelerated oxidation test)»
- DIN EN 15751 «Automotive fuels - Fatty acid methyl ester (FAME) fuel and blends with diesel fuel - Determination of oxidation stability by accelerated oxidation method»
