NOVELTY - Water vapor and carbon of solid-form carbon material are reacted to form a synthesis gas. Methane is synthesized from the synthesis gas obtained, and methane is irradiated to generate acetylene. Methane and acetylene are reacted in presence of solid super strong acid catalyst to obtain butane. The obtained butane is contacted with a polymerization reaction catalyst, and is converted into propane.    USE - For producing butane and propane.    ADVANTAGE - By using inexpensive water and solid-form carbon material, the butane and propane is produced economically and continuously, in large quantities. Toxic substances, such as waste-water, are not ejected during manufacturing process, and hence environmental burden is very little. The increase in price of crude oil does not influence the manufacturing of butane or propane.    DETAILED DESCRIPTION - A solid-form carbon material is filled in an arc-plasma reaction chamber of a arc-plasma reactor having insulated casing, raw-material water supply port and synthesis-extraction opening and arc electrode. A micro arc route is formed in the gap between carbon materials. An arc generation electric power is applied to the arc electrode, and a micro arc plasma is generated in the arc route. Water or water vapor is supplied from water-supply port to the micro arc route. Water vapor and carbon of carbon material are reacted in the presence of arc plasma, and a synthesis gas containing hydrogen and carbon monoxide is generated. The synthesis gas obtained is extracted and cooled. The cooled synthesis gas is introduced into a methylation-reaction tank, to synthesize methane. The methane is irradiated to generate acetylene. The methane and acetylene are reacted in presence of solid super strong acid catalyst to obtain butane. The obtained butane is contacted with a polymerization reaction catalyst and is converted into propane.    An INDEPENDENT CLAIM is included for an apparatus for manufacturing butane and propane, which has an insulated casing having an opening for inserting carbon material, a raw-material water supply port, an outlet for synthesis gas, an arc-plasma reaction chamber in the insulated casing, and an arc electrode in the arc-plasma reactor. The arc-plasma reactor has a micro arc route in the gap between the carbon materials filled in the reactor, a raw-material water feed pump for supplying water to the water-supply port, carbon-material supply apparatus for supplying carbon material to the opening for inserting the carbon material, a plasma power supply for generating synthesis gas, a methanation-reaction tank for synthesizing methane, a microwave acetylene synthesis tower for irradiating methane and generating acetylene, a solid super strong acid catalyst tower for synthesizing butane, and a polymerization-catalyst tower which contains polymerization reaction catalyst.    DESCRIPTION OF DRAWING(S) - The figure shows an apparatus for manufacturing butane and propane. (Drawing includes non-English language text).