Dimethyl Ether

Dimethyl ether (DME or CH3-O-CH3), is a new fuel that has attracted much atten­tion recently. Today DME is made from natural gas, but DME can also be produced by gasifying biomass. DME can be stored in liquid form at 5 to 10 bars pressure at normal temperature. A major advantage of DME is its naturally high cetane number, which means that self-ignition is easier. The high cetane rating makes DME most suitable for use in diesel engines, which implies that the high level of efficiency of the diesel engine is retained when using DME. The energy content of DME is lower than in diesel.

DME can be produced effectively from biosyngas in a single-stage, liquid-phase (LPDME) process. The origin of syngas includes a wide spectrum of feedstocks such as coal, natural gas, biomass, and others. Nontoxic, high-density, liquid DME fuel can be easily stored at modest pressures. The production of DME is very similar to that of methanol. DME conversion to hydrocarbons, lower olefins in particular, has been studied using ZSM-5 catalysts with varying SiO2/Al2O3 ratios, whereas the DME carbonization reaction to produce methyl acetate has been studied over a variety of group VIII metal-substituted heteropolyacid catalysts.