... the purity is 96% or 98%min Product name: Sodium Sulfite Anhydrous, Sodium Sulphite Anhydrous Molecular formula : Na2SO3Appearance : white crystalline powderQuality standard: HG/ ... Premium grade Super grade First grade Salable product Industrial grade Sodium sulfite ( Na2SO3 ) , % ≥97.0 96.0 93.0 90 ... : used in papermaking, leather, printing, dyeing, bleaching and food . sodium sulphite anhydrous