The synthesis and utilisation of ionic liquids in the removal of harmful impurities from fuel

• Main Author: Corbett, Paul
• Other Authors: Hallett, Jason
• Published: Imperial College London 2016
• Subjects: 662.6
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.712947

The development of a pure and thus efficient fuel is of increasing importance in the use of a finite resource to be environmentally responsible and economically viable. Trace amounts of dissolved sodium has been identified as a suspect leading to the formation of internal diesel injector deposits (IDIDs) which proves problematic by reducing fuel efficiency in high pressure diesel injectors. Zinc contaminants have been identified as suspects leading to nozzle deposit formation and copper contaminants quickly reduce the oxidation stability of diesel fuel. I demonstrate in this research the successful extraction of ppm levels of Na+, Zn2+ and Cu2+ from model diesel fuels. A range of ionic liquids (ILs) with a variety of cations and anions were examined for their effectiveness at different loadings of IL relative to the fuel. Results provide several clear trends with some exceptional capabilities of the ILs in the extractions. The tunable properties of the ILs ions allow the ‘design’ to meet the requirements for a particular target and here provide several potential candidates for the extractions 23Na NMR was used in the determination of donor number (DN) and Kamlet-Taft parameters were gathered for each IL providing information of possible hydrogen-bond acidity / basicity (α / β) and dipolarity/polarizability solvent strength (π*). In addition the non-random two liquid model (NRTL) was applied to correlate the experimental extraction results and determine τ parameters for each of the ILs. Donor number (DN), τ parameters and β values in addition to interfacial tension and viscosity provide information of the extraction mechanisms and predict performance, enabling a chemical design of ILs that are ideal for fuel purification.