FIELD: bleaching of cellulose and lignocellulose materials with use of hydrogen peroxide as bleaching reagent. SUBSTANCE: method includes short-time high- temperature stage at pressure sufficient for prevention of boiling, and longer stage at atmospheric pressure and low temperature to provide for reaction with considerable part of hydrogen peroxide remained after the short stage. Method includes the following operations. Cellulose is introduced at concentration of 10-18% into mixer, where it is heated to temperature above 100 C, and sufficient amount of sodium hydroxide is added to obtain cellulose pH up to 8.5. Then, sufficient amount of hydrogen peroxide is added, approximately, from 0.5 to 5.0% of cellulose weight. Cellulose is passed through reaction column at velocity ensuring reaction time in said column from 1 to 30 min. Cellulose is held in reaction column at atmospheric pressure for reaction for 1-5 h until considerable amount of residual hydrogen peroxide by bringing pH to, at least, 9 between stages of bleaching. EFFECT: higher efficiency of cellulose bleaching and reduced capital costs. 16 cl, 9 dwg, 7 tbl
