TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The catalyst comprises a solid support, comprising alumina, zeolite, silica, titania, zirconia, activated carbon or another carbon material. The catalyst (I) comprises the support material with a metal loading of 5-30 wt.%, preferably 10.wt%. The catalyst (I) is a combined ruthenium-based and nickel-based catalyst on gamma -alumina support. The support material is alumina including gamma -alumina (preferred), silica, zeolite and/or activated carbon. The bi-metallic catalyst comprises 10% of nickel and 1.72% of ruthenium. Preferred Process: The bi-metallic catalyst is calcinated. In step (a2), the aqueous solution of water soluble salt of nickel and the aqueous solution of a water soluble salt of ruthenium are mixed prior to addition of the solid support. In the process for converting an organic feedstock to methane, the catalyst (I) comprises 5-25 wt.% of nickel and 1-5 wt.% of ruthenium.    TECHNOLOGY FOCUS - INSTRUMENTATION AND TESTING - Preferred Components: The methane capturing device is within an internal combustion engine, a storage system, or a power generating system. The methane capturing device comprises a separator for separating methane from the product mixture. The system is a continuous system or a batch system. In the system, one or both of the water feed and the feedstock feed comprise a preheater. The weight hourly space velocity in the system and in the process (continuous flow process) is 1-500 per hour, preferably 25.2 per hour. The pressure in the heated reactor or in the SCW reactor is 22-50 MPa.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Process: The reaction mixture in the reactor is maintained at 350-600 degrees C, preferably 500 degrees C. The reforming of the hydrocarbon feedstock produces a product mixture comprising at least 34% methane, preferably at least 60% methane. The step (d) comprises separating the methane from the product mixture. The process for reforming hydrocarbon feedstock to produce methane, is a batch process or a continuous process. In the process for conversion of ethanol to methane, the ethanol and the SWC are contained in a heated reactor further containing the catalyst (I), where a pressure in the heated reactor is 22 MPa-50 MPa. Preferred Components: The ratio of SCW to hydrocarbon feedstock in the SCW reactor is 1:1-5:1, preferably 2:1-4:1. The ratio of SCW to ethanol is 3:1. The molar ratio of catalyst (I) to feedstock is 0.5-20% and molar ratio of catalyst (I) to ethanol is 2%. The organic feedstock is ethanol (preferred), acetone, methanol and/or butanol. EXAMPLE - Ethanol sample (8.520 g) was weighed into the reactor, followed by adding a precisely controlled amount of distilled water. The potassium carbonate catalyst was added into the solution at a catalyst-to-ethanol molar ratio of 2%. The air inside the reactor was displaced with high purity nitrogen. The reactor was then pressurized with nitrogen and was heated at 10 degrees C/minute up to the specified reaction temperature (in the range of 350-500 degrees C). After the desired reaction temperature was reached, the reactor was maintained at that temperature for 30-120 minute before being cooled rapidly to room temperature. Once the reactor was cooled to room temperature, the gas inside was released through a condenser into a gas-collecting vessel. The liquid products and solid residue inside the reactor and the condenser were rinsed completely with distilled water and acetone. After filtration, the solid residue and catalyst was separated and dried at 105 degrees C for 4 hour in an oven, to obtain a gaseous product (e.g. methane).