TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Method: In the step (b) or step (c), a carrier gas is introduced into the reactor, and in the step (d) hydrogen gas mixed with the carrier gas is discharged. In the step (c), the reactor is maintained by pressure of 0.5-300 atm and at temperature of 500-1300 K. Preferred Components: The solid acid mixture further includes at least one of metal and electrolyte. The carrier gas is hydrogen, nitrogen, argon or carbon dioxide. The solid acid catalyst is zeolite, bentonite, kaolinite, attapulgite, montmorillonite, zinc oxide, aluminum oxide, titanium oxide, cesium oxide, vanadium oxide, silicon oxide, chromium oxide, calcium sulfate, manganese sulfate, nickel sulfate, copper sulfate, cobalt sulfate, cadmium sulfate, magnesium sulfate, iron(II) sulfate, aluminum sulfate, calcium nitrate, zinc nitrate, ferric nitrate, aluminum phosphate, ferric phosphate, chromium phosphate, copper phosphate, zinc phosphate, magnesium phosphate, aluminum chloride, titanium chloride, calcium chloride, calcium fluoride, barium fluoride, calcium carbonate and/or magnesium carbonate. The metal is aluminum, zinc, titanium, nickel, copper, gold, platinum, rhodium, palladium, iridium, selenium and/or its alloy. The electrolyte is sodium chloride, potassium chloride, sodium nitrate, potassium nitrate, sodium sulfate, potassium sulfate, lithium carbonate, sodium carbonate, potassium carbonate, sodium dihydrogen phosphate, disodium hydrogen phosphate, sodium hydroxide, potassium hydroxide, calcium chloride, magnesium chloride, calcium nitrate, magnesium nitrate, calcium sulfate, magnesium sulfate, calcium hydroxide and/or magnesium hydroxide. The carbon material, the solid acid, the metal, and the electrolyte are in powdered form having particle size of 20-500 meshes. The solid acid mixture has metallic particles deposited in pores of the solid acid powder, and the metallic particles have diameter of less than or equal to 10 mu m. The solid acid mixture has metallic powder coated on surface of the solid acid powder or solid acid powder coated on surface of the metallic powder, where the coated metallic film or solid acid film has thickness of 10 nm to 10 mu m. The solid acid mixture comprises greater than or equal to 60 wt.%, preferably greater than or equal to 70 wt.% carbon material and solid acid, and less than or equal to 40 wt.%, preferably less than or equal to 30 wt.% metal. The reactor comprises iron greater than or equal to 70%, and material comprising stainless steel and/or carbon steel.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The carbon material is activated carbon, graphite, amorphous carbon, carbon nanotube, carbon nanofibers, coal and/or charcoal. EXAMPLE - No suitable example given.