Submitted to: European Journal of Lipid Science and Technology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 5/22/2009
Publication Date: 10/1/2009
Citation: Holser, R.A. 2009. Temperature-dependent solubility of wax compounds in ethanol. European Journal of Lipid Science and Technology Vol 111 Issue 10 No 10 pg 1049-1052.2009. Interpretive Summary: Ethanol was used to dissolve wax compounds similar to those found on plant tissues. Usually a solvent such as hexane or petroleum ether is required, however, when the ethanol is heated it becomes an effective solvent. This approach was proposed to recover the waxes and other lipid compounds from biomass that will be used in the production of bioethanol. The waxes can be removed from the biomass at the beginning of the conversion process to provide a valuable co-product. Such an integrated process will improve the efficiency of conversion and process economics.
Technical Abstract: The ability of ethanol to dissolve wax compounds was investigated as an alternative to traditional lipid solvents. The solubility of fatty esters with carbon chain lengths between 46 and 54 was measured in ethanol at elevated temperatures. The greatest increase in solubility was observed between 40°C and 60°C for the longer chain waxes. The solubility of a 52 carbon wax increased by a factor of four over this temperature range. The Van’t Hoff equation was used to estimate enthalpy of solution values. Ethanol is an effective lipid solvent at these modestly elevated temperatures and offers an economical method to recover lipid co-products from biomass prior to conversion to bioethanol.