Production of oxymethylene dimethyl ether (OME)-hydrocarbon fuel blends in a one-step synthesis/extraction procedure. (15th February 2018)

• Record Type: Journal Article
• Authors: Oestreich, Dorian; Lautenschütz, Ludger; Arnold, Ulrich; Sauer, Jörg
• Is Part Of: Fuel. Volume 214(2018)
• Page Start: 39
• Page End: 44
• Publication Date: 2018-02-15
• Subjects: Oxymethylene dimethyl ethers -- Diesel fuels -- Emission reduction -- Fuel additives -- Methanol -- Oxygenate fuels; Fuel -- Periodicals; Coal -- Periodicals; Coal; Fuel; Periodicals; 662.6
• DOI: 10.1016/j.fuel.2017.10.116
• Languages: English
• ISSNs: 0016-2361

Abstract

Graphical abstract: Highlights: OMDMEs and OMDEEs were synthesized from p -formaldehyde and methanol or ethanol. Reaction mixtures were extracted with n-dodecane, diesel and HVO, respectively. Fuel characteristics of OME-HVO and OME-diesel blends have been determined. OME-HVO and OME-diesel blends meet current diesel standards to a large extent. Fuel blends can be obtained in one step by reaction and simultaneous extraction. Abstract: Oligomeric oxymethylene dimethyl ethers (OMEs) of the type CH3 O-(CH2 O)n -CH3 are promising diesel fuels with an enormous potential for the reduction of soot and NOx emissions. Oligomers with n = 3–5 are particularly advantageous, since their physicochemical and combustion properties are similar to conventional diesel. OMEs can be produced from methanol and formaldehyde but a series of byproducts, especially hemiformals, glycols, water and minor amounts of cyclic ethers, are also formed. These need to be separated from the product mixtures, which affects efficiency of this synthesis pathway. To isolate the desired OMEs, a one-step synthesis/extraction procedure is described. It implies highly selective extraction of OMEs from aqueous reaction solutions employing hydrocarbons as extraction agents. If fuel-type hydrocarbons are used, the resulting OME-hydrocarbon blends can be directly used in fuel applications. The corresponding oxymethylene diethyl ethers (OMDEEs) have also been investigated. Compared to OMEs, OMDEEs exhibit an increased solubility in nonpolar media but, as a result, solubility of educts and byproducts also increases. OME blends with hydrogenated vegetable oil and diesel have been prepared containing 10% of OMEs. It could be shown that such blends meet current diesel standards to a large extent.