liu.seSearch for publications in DiVA
Change search
ReferencesLink to record
Permanent link

Direct link
Qualitative and Quantitative Analysis of Biodiesel Deposits Formed on a Hot Metal Surface
Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
2013 (English)Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
Abstract [en]

This thesis aims to investigate the formation of deposits from thermally degraded biodiesel on a hot metal surface under the influence of sodium or copper contaminations. Biodiesel or Fatty Acid Methyl Esters (FAMEs) is a widely utilized biofuel with the potential to replace fossil fuels, however, issues regarding the thermal and oxidative stability prevent the progress of biodiesel for utilization as vehicle fuel. The thermal degradation of biodiesel causes formation of deposits often occurring in the fuel injectors, which could result in reduced engine efficiency, increased emissions and engine wear. However, still have no standard method for evaluation of a fuels’ tendency to form deposits been developed. In this study biodiesel deposits have been formed on aluminum test tubes utilizing a Hot Liquid Process Simulator (HLPS), an instrument based on the principle of the Jet Fuel Thermal Oxidation Tester (JFTOT). Quantitative and qualitative analyses have been made utilizing an array of techniques including Scanning Electron Microscopy (SEM), Gas Chromatography Mass Spectrometry (GCMS) and Attenuated Total Reflectance Fourier Transform Infrared Spectrometry (ATR-FTIR). A multi-factorial trial investigating the effects of sodium hydroxide and copper contaminations at trace levels and the impact of a paraffin inhibitor copolymer additive on three different FAME products, two derived from rapeseed oil and one from waste cooking oil as well as a biodiesel blend with mineral diesel, was conducted.The results exhibited that FAMEs are the major precursor to deposit formation in diesel fuel. The SEM analyses exploited the nature of FAME deposits forming porous structures on hot metal surfaces. Sodium hydroxide proved to participate in the deposit formation by forming carboxylic salts. However, the copper contamination exhibited no enhancing effect on the deposits, possibly due to interference of the blank oil in which copper was received. The paraffin inhibitor functioning as a crystal modifier had significant reducing effect on the deposit formation for all biodiesel samples except for the FAME product derived from waste cooking oil. Further studies are needed in order to investigate the influence of glycerin and water residues to the biodiesel deposit formation. Mechanisms involving oxidative or thermal peroxide formation, polymerization and disintegration have been suggested as degradation pathways for biodiesel. The involvement of oxidation intermediates, peroxides, was confirmed by the experiments performed in this thesis. However, the mechanisms of biodiesel deposit formation are complex and hard to study as the deposits are seemingly insoluble. Nevertheless, ATR-FTIR in combination with JFTOT-processing has potential as standard method for evaluation of deposit forming tendencies of biodiesel.

Place, publisher, year, edition, pages
2013. , 70 p.
Keyword [en]
Fatty Acid Methyl Ester (FAME), Biodiesel deposits, SEM/EDS, ATR-FTIR, GCMS
National Category
Chemical Sciences
URN: urn:nbn:se:liu:diva-95617ISRN: LITH-IFM-A-EX—13/2753—SEOAI: diva2:636870
External cooperation
Exova Materials Technology
Subject / course
Chemical Biology
2013-06-14, Planck, Linköping, 15:00 (Swedish)
Available from: 2013-08-12 Created: 2013-07-13 Last updated: 2013-08-16Bibliographically approved

Open Access in DiVA

Master Thesis Report Emilie Westberg(4769 kB)766 downloads
File information
File name FULLTEXT01.pdfFile size 4769 kBChecksum SHA-512
Type fulltextMimetype application/pdf

Search in DiVA

By author/editor
Westberg, Emilie
By organisation
Department of Physics, Chemistry and BiologyThe Institute of Technology
Chemical Sciences

Search outside of DiVA

GoogleGoogle Scholar
Total: 766 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Total: 393 hits
ReferencesLink to record
Permanent link

Direct link