摘要 |
Process for delignifying and bleaching pulp Process for the delignification and bleaching of pulp, comprising a first bleaching stage with hydrogen peroxide in the presence of a molybdate or tungstate in an acidic aqueous mixture; subsequent to the first bleaching stage, a second bleaching stage with hydrogen peroxide in an alkaline aqueous mixture; and, subsequent to the second bleaching stage, a third bleaching stage with hydrogen peroxide in the presence of a molybdate or tungstate in an acidic aqueous mixture. |