TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Component: The paraffins are propane, butane, pentane, hexane, and/or heptane.The isoparaffins are isobutane; isopentane; 2,2-dimethylbutane; 2,3-dimethylbutane; 2-methylpentane; 3-methylpentane; 2,2-dimethylpentane; 2,4-dimethylpentane; 2,2,3-trimethylbutane; 3,3,-dimethylpentane; 2-methylhexane; 2,3-dimethylpentane; 3-methylhexane; and/or 3-ethylpentane.The product hydrocarbon isomer(s) is isopentane; 2,2-dimethylbutane; 2,3-dimethylbutane; 2-methylpentane; 3-methylpentane; 2,2-dimethylpentane; 2,4-dimethylpentane; 2,2,3-trimethylbutane; 3,3,-dimethylpentane; 2-methylhexane; 2,3-dimethylpentane; 3-methylhexane; 3-ethylpentane; 2,2,4-trimethylpentane; 2,2-dimethylhexane; 2,5-dimethylhexane; 2,4-dimethylhexane; 3,3-dimethylhexane, 2,3,4-trimethylpentane; 2,3,3-trimethylpentane; 2,3-dimethylhexane; 2-methyl-3-ethylpentane; 2-methylheptane; 4-methylheptane; 3,4-dimethylhexane; 3-methylheptane; 2,2,5-trimethylhexane; and/or preferably isobutane.The sulfone component comprises sulfone of formula R-SO-R', or preferably sulfolane; 3-methylsulfolane; and/or 2,4-dimethylsulfolane.R, R' = monovalent hydrocarbon alkyl or aryl substituents containing 1-8C.The feed hydrocarbon and/or the ethylene are present in a hydrocarbon-containing fluid.Preferred Composition: A weight ratio of total weight of total hydrocarbon/ethylene is at least 1:1 but not more than 30:1.The hydrogen halide component, the sulfone component and the metal halide component is at least 50 but not more than 90 wt.%, at least 10 but not more than 35 wt.%, and at least 0.01 but not more than 20, wt.% based on total weight of the catalyst composition, respectively.The weight ratio of the catalyst composition/total hydrocarbon and ethylene is at least 0.5:1 but not more than 20:1.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Component: The hydrogen halide component is hydrogen chloride, hydrogen bromide and/or preferably hydrogen fluoride.The metal halide component is metal of groups III-V, preferably boron, aluminum, indium, tin, titanium, zirconium, phosphorus, antimony, bismuth, vanadium, niobium and/or tantalum.A halide of metal halide component is fluoride, bromide, and/or chloride, preferably antimony pentafluoride, tantalum pentafluoride, niobium pentafluoride, tin tetrafluoride, aluminum trichloride, tin tetrachloride, aluminum tribromide and/or titanium tetrafluoride.The catalyst composition comprises hydrofluoric acid, sulfolane and titanium tetrafluoride.    TECHNOLOGY FOCUS - CHEMICAL ENGINEERING - Preferred Condition: When the feed hydrocarbon comprises butane, isobutane, propane, or isopentane; the product hydrocarbon isomer is isobutane or isopentane.The conversion conditions comprises a temperature of at least 0 degreesF (preferably not more than 250 degreesF), a pressure of at least 40 (preferably not more than 1000) psig, and a time of at least 0.05 minute, preferably more than 2 hours.Preferred Process: The contacting step involves converting the feed hydrocarbon(s).The converting step is by reacting, alkylating, isomerizing, and/or disproportionating.The process is able to convert at least 50 (preferably at least 80) wt.% ethylene. EXAMPLE - A batch reactor was charged catalyst composition containing hydrofluoric acid (68.88 g), sulfolane (7.64 g) and titanium tetrafluoride (22.96 g) and stirred at 500 rpm. A hydrocarbon-containing fluid was blended to cylinder (500 ml). The higher boiling component(s) was added first, followed by supplied of ethylene, and weighed after desired amount of ethylene was added. The hydrocarbon-containing fluid was added to the reactor over 30-60 seconds. The reactor was allowed to performed conversion at 400 psig. The reactor contents were transferred to a settler. The acid components settled to the bottom of the gauge and removed into a cylinder for further use. The hydrocarbon phase was collected into cylinder containing 1.5 N potassium hydroxide (100 ml) to neutralize acid species. The water layer was removed and hydrocarbon layer was analyzed. Result showed the process was able to convert over 90% of the ethylene and 70% of normal butane was converted.