FIELD: woodworking industry.
SUBSTANCE: claimed group of inventions relates to methods for the production of kraft cellulose with high yield. Methods include: the production of kraft cellulose with a permanganate number of at least 20; the processing of kraft cellulose with a composition including: a) organic aminophosphonate, b) magnesium salt, and c) one or more anionic linear alcohols and ethoxylates or anionic polyacrylate, while organic aminophosphanate is selected from diethylenetriaminepentamethylenephosphonic acid (DTMP), aminotrismethylenephosphonate (ATMP), (bis)hexamethylenetriaminepentamethylenephosphonic acid (BHMTPMP), polyaminopolyestermethylenephosphonate (PAPEMP) and combinations thereof, while anionic linear alcohols and ethoxylates are selected from sodium laurylestersulfate (SLES), sodium laurylesterphosphate (SLEP), sodium laurylsulfate (SLS) and combinations thereof; and the decrease in the initial permanganate number of kraft cellulose to a given final permanganate number, while kraft cellulose is processed with the composition before a two-stage process of oxygen delignification, while final viscosity of cellulose remains high compared to kraft cellulose unprocessed with oxygen delignification.
EFFECT: methods improve a process of cellulose fiber delignification in the chemical production of wood pulp.
5 cl, 8 dwg, 38 tbl, 12 ex
