... or gas covering the complete acid,neutral and alkali range up to pH 11,exept hydrofluoric acid and fully desalted water. (As ... water,Caustic soda,concentrated sulphuric acid,aluminium hydroxide; b:Filtration of catalyst and decoloration liquids of activated charcoal ... ,steam,catalysis air of petrochemical industry,separation of acid mist,high temperature dusty gas in environmental protection industry ...