Dimethyl ether

Polyethylene glycolMethanolDimethyl ether (DME, also known as methoxymethane) is the organic compound with the formula CH3OCH3, simplified to C2H6O. The simplest ether, it is a colorless gas that is a useful precursor to other organic compounds and an aerosol propellant that is currently being demonstrated for use in a variety of fuel applications. It is an isomer of ethanol. Dimethyl ether (DME, also known as methoxymethane) is the organic compound with the formula CH3OCH3, simplified to C2H6O. The simplest ether, it is a colorless gas that is a useful precursor to other organic compounds and an aerosol propellant that is currently being demonstrated for use in a variety of fuel applications. It is an isomer of ethanol. Approximately 50,000 tons were produced in 1985 in Western Europe by dehydration of methanol: The required methanol is obtained from synthesis gas (syngas). Other possible improvements call for a dual catalyst system that permits both methanol synthesis and dehydration in the same process unit, with no methanol isolation and purification.Both the one-step and two-step processes above are commercially available. The two-step process is relatively simple and start-up costs are relatively low. A one-step liquid-phase process is in development. Dimethyl ether is a synthetic second generation biofuel (BioDME), which can be produced from lignocellulosic biomass. The EU is considering BioDME in its potential biofuel mix in 2030; It can also be made from biogas or methane from animal, food, and agricultural waste, or even from shale gas or natural gas. The Volvo Group is the coordinator for the European Community Seventh Framework Programme project BioDME where Chemrec's BioDME pilot plant is based on black liquor gasification in Piteå, Sweden. The largest use of dimethyl ether is as the feedstock for the production of the methylating agent, dimethyl sulfate, which entails its reaction with sulfur trioxide: Dimethyl ether can also be converted into acetic acid using carbonylation technology related to the Monsanto acetic acid process: Dimethyl ether is a low-temperature solvent and extraction agent, applicable to specialised laboratory procedures. Its usefulness is limited by its low boiling point (−23 °C (−9 °F)), but the same property facilitates its removal from reaction mixtures. Dimethyl ether is the precursor to the useful alkylating agent, trimethyloxonium tetrafluoroborate. A mixture of dimethyl ether and propane is used in some over-the-counter 'freeze spray' products to treat warts, by freezing them. In this role, it has supplanted halocarbon compounds (Freon).