TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Component: The indium halide is InX and/or InX3. The reactor also contains zinc halide.X = Cl, Br, and/or I.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Process: In addition to methanol and/or dimethyl ether reactants, there may also be introduced to the reactor additional feedstock components from hydrocarbons, halogenated hydrocarbons, or oxygenated hydrocarbons. The additional feedstock components act as initiators and/or promoters for the reaction to produce branched chain hydrocarbons. The reactor contains compound(s) that can act as initiators for the reaction selected from alcohols, ethers, olefins and dienes and having at least 2 carbon atoms. There is present in the reactor promoter(s) from hydrogen halide(s) and alkyl halides of 1-8C. The process is operated in the liquid phase. The methanol and/or dimethyl ether can be contacted with the indium halide at 100-300 degrees C. The reaction is performed at 1-100 barg or in the presence of hydrogen, a hydrogenation catalyst, or carbon monoxide. The process is a continuous or semi-continuous for the production of branched chain hydrocarbons from methanol and/or 1-5-dimethyl ether comprising contacting, in a liquid phase reaction composition in a reactor, methanol and/or dimethyl ether with a catalyst comprising indium halide, and to at least 100 degrees C to produce a product mixture comprising methanol and/or dimethyl ether and a hydrocarbon reaction product comprising branched chain hydrocarbons. The catalyst is maintained in the reactor in an active form and in an effective concentration. The catalyst comprising indium halide is maintained in an active form and in an effective concentration in the reactor by recycling to the reactor, one or more promoter compounds from downstream product recovery stage(s).Preferred Component: The additional feedstock components are olefins, dienes, alcohols, or ethers. The liquid reaction composition comprises at least one further additional feedstock component, preferably having been recycled from downstream product recovery stage(s). EXAMPLE - Indium iodide (InI3) (14.38 g), methanol (1.87 g), and ethanol (0.17 g), were weighed into a glass pressure tube. The contents were agitated and shaken. Some heat was evolved. Once the tube and contents had cooled methyl iodide (0.08 g) was added and the tube was sealed. The tube was encased in steel mesh and placed in an oven at 200 degrees C for 2 hours. On cooling the tube contained two liquid layers and negligible precipitate. The top organic layer was clear and an aliquot was removed for analysis. The analysis showed the organic layer to contain a range of branched chain hydrocarbons, including iso-butane, iso-pentane, 2,3-dimethylbutane, and triptane. It showed increased iso-pentane and 2,3-dimethylbutane products.