Open AccessChemical Changes in Fossil and Biogenic Heating Oils on Long-Term Storage
Author(s) -
Stefanie Kerkering,
Jan Andersson
Publication year - 2015
Publication title -
energy and fuels
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.861
H-Index - 186
eISSN - 1520-5029
pISSN - 0887-0624
DOI - 10.1021/ef502344d
Subject(s) - chemistry , mass spectrometry , gas chromatography , organic chemistry , carboxylic acid , polymerization , environmental chemistry , chromatography , polymer
The formation of sediments in biogenic and fossil heating oils as well
as in their blends is a well-known problem. These deposits can plug
filters and nozzles in heating systems and, consequently, cause economic
losses. Polymerization and the formation of corrosive acids are
possible explanations for these incidents. To study the influence of
long-term storage on different heating oils (biogenic, fossil, and a 10%
blend) and to investigate the changes in their composition, the oils
were stored for a period of 12–24 months at nearly ambient (40 °C) and
analyzed with different techniques every 6 weeks. The formation of
several kinds of oxidation products was demonstrated, including ketones,
epoxides, aldehydes, carboxylic acids, and furans. Size-exclusion
chromatography was used to demonstrate the formation of oligomeric
products of the fatty acid methyl esters (FAMEs) (up to pentamers).
Short-chain (C1–C6) carboxylic acids were
quantified with ion chromatography, and larger carboxylic acids were
indicated by mass spectrometry. The first recorded experimental evidence
for a coupling reaction between a FAME and components of the fossil
oil, namely, such containing the nitrogen heterocycle indols, is
described. Cross-coupling products between biogenic and fossil compounds
were detected using Orbitrap ultrahigh-resolution electrospray
ionization mass spectrometry