公开(公告)号：US20190186075A1

公开(公告)日：2019-06-20

申请号：US16311213

申请日：2017-06-27

Applicant: KEMIRA OYJ

Inventor： Leif ROBERTSÉN ,  Veli-Matti VUORENPALO ,  Anna-Maija PERANDER ,  Pentti PEKONEN ,  Jonas KONN

IPC: D21C9/10 ,  D21C9/16

CPC classification number: D21C9/1036 ,  D21C9/163 ,  D21C9/166

Abstract: The present invention relates to a process for treating pulp comprising a step, wherein the pulp is treated with distilled percarboxylic acid, such as distilled per-carboxylic acid (dPAA), and peroxide, such as hydrogen peroxide.

公开(公告)号：US20200181063A1

公开(公告)日：2020-06-11

申请号：US16627055

申请日：2018-06-27

Applicant: Kemira Oyj

Inventor： Reijo AKSELA ,  Jonas KONN ,  Anna-Maija PERANDER ,  Anna HAARALA ,  Riitta ILMONIEMI ,  Hanna HOFFREN

IPC: C07C227/16 ,  D21C9/10 ,  C07C229/12

Abstract: The present invention relates to a process for in situ the preparation of mixtures of chelating agents by catalyzed reactions of diethanolamine derivatives with maleic acid and then with 2-halocarboxylic acid, to mixtures of chelating agents and methods using such chelating agents.

公开(公告)号：US20240360253A1

公开(公告)日：2024-10-31

申请号：US18688022

申请日：2022-09-21

Applicant: KEMIRA OYJ

Inventor： Asko KARPPI ,  Matti HIETANIEMI ,  Giorgio VANZETTI ,  Jonas KONN ,  Tomi KEMPAS

IPC: C08F8/28 ,  D21H17/45 ,  D21H21/18

CPC classification number: C08F8/28 ,  D21H17/455 ,  D21H21/18 ,  C08F2810/10

Abstract: Method for on-site glyoxylation of polyacrylamide in paper mill, board mill or the like is disclosed. Discontinuous batch glyoxylation reaction of aqueous reaction mixture is performed. The method comprises forming or obtaining the aqueous reaction mixture having a start viscosity and comprising polyacrylamide base polymer having weight average molecular weight of 30 000-300 000 g/mol and glyoxal. Concentration of the polyacrylamide base polymer in the reaction mixture is 1.5-8% above a Critical Concentration of the polyacrylamide base polymer. A feed of an alkali is added to the reaction mixture while measuring viscosity of the reaction mixture and/or a process variable related to the viscosity of the reaction mixture and the on-site glyoxylation reaction of polyacrylamide base polymer in the reaction mixture is allowed to proceed. When a predetermined end viscosity value is attained the feed of alkali is ended and acid is added to the reaction mixture.

公开(公告)号：US20230212821A1

公开(公告)日：2023-07-06

申请号：US17928721

申请日：2021-06-14

Applicant: KEMIRA OYJ

Inventor： Leif ROBERTSEN ,  Jonas KONN

IPC: D21H21/02 ,  D21H17/37 ,  D21H17/45 ,  D21C9/08 ,  D21C9/14 ,  D21H11/04

CPC classification number: D21H21/02 ,  D21C9/086 ,  D21C9/142 ,  D21H11/04 ,  D21H17/375 ,  D21H17/455

Abstract: The invention relates to a method for pitch control and/or removal during bleaching of cellulosic fibres. Cellulosic fibres are obtained from a pulping process and formed into an aqueous cellulosic fibre suspension, and bleaching of the cellulosic fibre suspension is performed in a bleaching process comprising at least one acidic stage, where pH of the cellulosic fibre suspension is

公开(公告)号：US20200223786A1

公开(公告)日：2020-07-16

申请号：US16627016

申请日：2018-06-27

Applicant: Kemira Oyj

Inventor： Reijo AKSELA ,  Jonas KONN ,  Anna-Maija PERANDER ,  Anna HAARALA ,  Riitta ILMONIEMI ,  Hanna HOFFREN

IPC: C07C227/16 ,  D21C9/10 ,  B01J23/10

Abstract: The present invention relates to a process for the in situ preparation of mixtures of chelating agents by catalyzed reactions of diethanolamine with maleic acid and then with 2-halocarboxylic acid, mixtures obtainable using said process and mixtures of chelating agents. In addition, the invention relates to methods where such mixtures are used.