Process for reductively bleaching wood pulp

    公开(公告)号:DE3308298A1

    公开(公告)日:1984-09-13

    申请号:DE3308298

    申请日:1983-03-09

    Applicant: BASF AG

    Inventor: MELZER JAROSLAV

    Abstract: In the process, wood pulp is reductively bleached by the action of water-soluble dithionites, formamidinesulphinic acid or water-soluble salts thereof in an aqueous medium at 40 to 100 DEG C in the presence of effective quantities of (1) 1-hydroxyethylidene-1,1-diphosphonic acid, (2) aminotri-(methylenephosphonic acid), (3) ethylenediaminetetra-(methylenephosphonic acid) and/or (4) diethylenetriaminepenta-(methylenephosphonic acid) or the sodium, potassium or ammonium salts of the said acids as complexing agents.

    PROCESS FOR THE PREPARATION OF NITROGEN-CONTAINING CONDENSATES, AND THEIR USE

    公开(公告)号:CA1162338A

    公开(公告)日:1984-02-14

    申请号:CA357446

    申请日:1980-07-31

    Applicant: BASF AG

    Abstract: process for the production of water-soluble auxiliaries for the papermaking industry by reacting (a) 1 part by weight of a polyamidoamine obtained by condens ing 1 mole of a dicarboxylic acid having from 4 to 10 carbon atoms with from 0.8 to 1.4 moles of a polyalkylene polyamine having from 3 to 10 alkyleneamine units and containing up to 8 ethleneimine units per basic nitrogen atom with (b) 0.1 to 4 parts by weight of an .alpha..omega.-dichloro polalkylene oxide obtained by reacting a polyalkylene oxide having from 8 to 100 alkylene oxide units with a compound selected from the group consisting of a thionyl chloride and phosgene and then cleaving the reaction products by heating them to a temperature of from 70.degree. to 150.degree.c in the presence of a tertiary amine as catalyst, as crosslinking agent, at a temperature above 20.degree.c in aqueous solution or in a water-soluble organic solvent, the reaction being carried out to a point at which the viscosity of an aqueous solution containing 20% by weight of auxiliary is from 300 to 2,500mPas..

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