Global Patent Index - EP 0681624 A1

EP 0681624 A1 19951115 - METHOD FOR CHLORINE-FREE BLEACHING OF PULP WITH ACETIC ACID AS ACIDIFYING AGENT.

Title (en)

METHOD FOR CHLORINE-FREE BLEACHING OF PULP WITH ACETIC ACID AS ACIDIFYING AGENT.

Title (de)

VERFAHREN ZUR CHLORFREIEM BLEICHEN VON ZELLSTOFF MIT ESSIGSÄURE ALS ANSÄUERUNGSMITTEL.

Title (fr)

PROCEDE DE BLANCHIMENT SANS CHLORE DE PATE A PAPIER, DE L'ACIDE ACETIQUE ETANT UTILISE COMME AGENT ACIDIFIANT.

Publication

EP 0681624 A1 19951115 (EN)

Application

EP 94905899 A 19940126

Priority

  • SE 9400054 W 19940126
  • SE 9300277 A 19930129

Abstract (en)

[origin: WO9417239A1] A method of bleaching pulp of cellulosic fibre material without the use of chlorine when manufacturing chemical pulp is described, wherein the pulp entering is fed continuously in a bleaching line and is treated with a sequestering agent in the presence of an acid in order to adjust the pH to a value below 7 and is thereafter bleached in a sequence of several stages consisting of peroxide, at least one organic per-acid and peroxide. According to the invention it is suggested that in the treatment with the sequestering agent the pulp is acidified with acetic acid.

IPC 1-7

D21C 9/16

IPC 8 full level

D21C 9/10 (2006.01); D21C 9/16 (2006.01)

CPC (source: EP)

D21C 9/1005 (2013.01); D21C 9/1042 (2013.01); D21C 9/163 (2013.01); D21C 9/166 (2013.01)

Citation (search report)

See references of WO 9417239A1

Designated contracting state (EPC)

AT DE ES FR PT SE

DOCDB simple family (publication)

WO 9417239 A1 19940804; AU 5982094 A 19940815; AU 675291 B2 19970130; BR 9406193 A 19960109; CA 2154076 A1 19940804; CN 1117301 A 19960221; EP 0681624 A1 19951115; FI 111387 B 20030715; FI 953589 A0 19950727; FI 953589 A 19950727; JP H08505907 A 19960625; NO 305763 B1 19990719; NO 952935 D0 19950724; NO 952935 L 19950913; SE 501325 C2 19950116; SE 501325 E 19990920; SE 9300277 D0 19930129; SE 9300277 L 19940730

DOCDB simple family (application)

SE 9400054 W 19940126; AU 5982094 A 19940126; BR 9406193 A 19940126; CA 2154076 A 19940126; CN 94191058 A 19940126; EP 94905899 A 19940126; FI 953589 A 19950727; JP 51693094 A 19940126; NO 952935 A 19950724; SE 9300277 A 19930129