maily use :the manufacture of the chemical ,paper ,aluminum smelting ,refining tungsten ,artifical silk ,rayon and soap manufacturing .productiong of the dyed ,plastics .pharmaceutical and organic intermediates ,the old rubber recycling ,metal sodium,water electroysis as we as the inorganic salt production ,preparation of borax ,chromium salts .manganess salt ,phosphate ,etc.nrrf to usa a lot of caustic soda