EP0864689A2 - Additive composition and process for reducing anthraquinone requirements in pulping of lignocellulosic material - Google Patents
Additive composition and process for reducing anthraquinone requirements in pulping of lignocellulosic material Download PDFInfo
- Publication number
- EP0864689A2 EP0864689A2 EP98400568A EP98400568A EP0864689A2 EP 0864689 A2 EP0864689 A2 EP 0864689A2 EP 98400568 A EP98400568 A EP 98400568A EP 98400568 A EP98400568 A EP 98400568A EP 0864689 A2 EP0864689 A2 EP 0864689A2
- Authority
- EP
- European Patent Office
- Prior art keywords
- group
- keto compound
- anthraquinone
- cyclic keto
- acid
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C3/00—Pulping cellulose-containing materials
- D21C3/22—Other features of pulping processes
- D21C3/222—Use of compounds accelerating the pulping processes
Definitions
- This invention relates to an improved additive composition and process for the delignification of lignocellulosic material, such as wood, with an alkaline pulping liquor of the kraft, or sulfate, alkaline pulping process. More particularly, the invention relates to lignocellulosic material delignification with kraft pulping liquors containing a cyclic keto compound (preferably, anthraquinone), permitting enhanced yield.
- a cyclic keto compound preferably, anthraquinone
- the invention relates to an improvement of said additive composition and process wherein said enhanced yield is achieved at reduced anthraquinone levels via the inclusion of a surfactant mixture comprising at least one alkyl alcohol alkoxylate and at least one polyoxyalkylene glycol ether of an ester of an acid selected from the group consisting of ricinoleic acid and 12-hydroxystearic acid.
- a surfactant mixture comprising at least one alkyl alcohol alkoxylate and at least one polyoxyalkylene glycol ether of an ester of an acid selected from the group consisting of ricinoleic acid and 12-hydroxystearic acid.
- One disadvantage to anthraquinone use is its tendency to cause scaling problems in the cooking vessel. Methods to overcome this problem are disclosed in U.S. Patent Nos.: 4,481,073 and 4,561,935.
- an object of this invention is to provide an improved pulping additive composition and process for delignification of a lignocellulosic raw material with,a pulping liquor with a cyclic keto compound, such as anthraquinone, for the production of a predetermined yield of cellulose pulp which composition and process permit the achievement of said yield, as well as other aforementioned benefits, with a reduced requirement of cyclic keto compound, such as anthraquinone, of at least 10%, and advantageously up to 50%.
- an improved wood pulping aid composition comprising a cyclic keto compound for addition to pulping liquors in the delignification of lignocellulosic raw material characterized in that it comprises the addition of a surfactant mixture comprising at least one alkyl alcohol alkoxylate and at least one polyoxyalkylene glycol ether of an ester of an acid selected from the group consisting of ricinoleic acid and 12-hydroxystearic acid.
- the invention provides an improved process for the delignification of lignocellulosic raw material in the production of cellulose pulps suitable for use in the manufacture of paper or paperboard comprising treating the lignocellulosic raw material in a closed reaction vessel with an alkaline pulping liquor with an amount of a cyclic keto compound included therein to achieve a determined pulp yield, characterized in that it comprises providing a reduction in the amount of the cyclic keto compound required to achieve said yield by adding to said alkaline pulping liquor a surfactant mixture comprising at least one alkyl alcohol alkoxylate and at least one polyoxyalkylene glycol ether of an ester of an acid selected from the group consisting of ricinoleic acid and 12-hydroxystearic acid.
- the present invention relates to the use of a surfactant mixture comprising at least one alkyl alcohol alkoxylate and at least one polyoxyalkylene glycol ether of an ester of an acid selected from the group consisting of ricinoleic acid and a 12-hydroxystearic acid as an additive to an alkaline pulping liquor, preferably in combination with a cyclic keto compound.
- the improved process of this invention comprises the steps of (1) treating lignocellulosic material in a closed reaction vessel with an alkaline pulping liquor containing a cyclic keto compound additive selected from the group consisting of naphthoquinone, anthraquinone, enthrone, phenanthrenequinone, the alkyl, alkoxy, and amino derivatives of said quinones, 6,11-dioxo-1H-anthra [1,2-c]pyrazole, anthraquinone-1,2-naphthacrinone, 7,12-dioxo-7,12-dihydroanthra[1,2-b]pyrazine, 1,2-benzanthraquinone, and 10-methylene enthrone, the treatment taking place at a maximum temperature of from about 150° to about 200°C for a period from about 0.5 to about 480 minutes to achieve a determined pulp yield, and (2) displacing the pulping liquor from the lignocellul
- the delignified cellulosic material produced by the above two steps may be used without further treatment or may be subjected to conventional bleaching steps.
- the lignocellulosic material to be treated is wood, it is first converted into the form of chips. This step is not required when the lignocellulosic material is of fibrous form.
- the lignocellulosic material may be refined between steps (1) and (2). Refining can be carried out with known equipment, such as a single disc or double disc refiner.
- the process of this invention may be used to delignify either coniferous or deciduous species of wood.
- coniferous is meant species such as pine, spruce, and balsam fir.
- deciduous is meant species such as birch, aspen, eastern cottonwood, maple, beech, and oak.
- the alkyl alcohol alkoxylate component of the surfactant mixture is preferably a C 4 -C 30 .
- alkyl alcohol alkoxylate prepared by reacting an alcohol, which may have either a linear or branched chain and may be either a primary or secondary alcohol, with from about 5 moles to about 100 moles of an alkylene oxide selected from the group of ethylene oxide, propylene oxide, butylene oxide, and any combination thereof.
- a particular preferred alkyl alcohol alkoxylate is oleyl alcohol ethoxylate prepared with 23 moles ethylene oxide.
- the member of the group of polyoxyalkylene glycol ethers of an ester of an acid selected from the group of ricinoleic acid and hydroxy stearic acid can be prepared by reacting an ester of a glycol, selected from the group of glycerine, neopentyl glycol, trimethylolethane, trimethylolpropane, pentaerythritol and its polymers, mannitol, and sorbitol, with from about 5 moles to about 100 moles of an alkylene oxide selected from the group of ethylene oxide, propylene oxide, butylene oxide, and any combination thereof.
- a glycol selected from the group of glycerine, neopentyl glycol, trimethylolethane, trimethylolpropane, pentaerythritol and its polymers, mannitol, and sorbitol
- ricinoleic acid is the primary component ( ⁇ 90%) of castor oil, although present as a triglyceride rather than in free acid form, castor oil may be alkoxylated directly to form the required polyoxyalkylene glycol ethers of the esters of ricinoleic acid. Therefore, a preferred member of this group is ricinoleic acid triglyceride ethoxylate.
- U.S. Patent Nos. 5,298,120 and 5,501,769 disclose pulping wood using fatty acid esters of polyoxyalkylene glycols to enhance pulping uniformity and pulp yield. While these esters may give the desired performance, there is an inherent weakness in the molecule when used in strongly alkaline solutions which are heated to high temperatures. The ester will cleave and form both a fatty acid soap and the polyalkylene glycol used to form the ester. Thus, it ceases to be the ester claimed. Also, the beneficial results are not being produced by the disclosed compound, rather the beneficial results are, in fact, diminished by the products of this cleavage.
- the presence of the sodium salt of the polyalkylene glycol ether of ricinoleic acid will assist in solubilizing the alkyl alcohol polyalkylene glycol ethers in the hot, alkaline pulping solution as the pulping process is completed.
- the solubilization of the other surfactants is of great benefit since, otherwise, these other surfactants may precipitate out of solution and be of less benefit.
- the composition of the invention is preferably a microemulsion prepared by combining an oleyl alcohol ethoxylate with a ricinoleic acid triglyceride ethoxylate in a weight ratio of from about 4:1 to about 1:4 (preferably, about 1:2), respectively.
- an aqueous solution of the composition is prepared by blending with from about 10 to about 30% (preferably, about 20%) water, producing a clear viscous solution. This solution is, in turn, diluted with water to form about 10 to about 30% (preferably, about 12.5%) active when combined with the aqueous dispersion of anthraquinone.
- the invention surfactant composition should exhibit an HLB of from about 5 to about 20 preferably from about 8 to about 16.
- a microemulsion is formed which exhibits an average particle size of from about 0.5 to about 10 ⁇ m, preferably from about 1 to about 4 ⁇ m and most preferably less than 2 ⁇ m.
- the cyclic keto compound preferably anthraquinone
- the anthraquinone dispersion is preferably prepared by the addition of a dispersant and by reducing the anthraquinone average particle size to from about 6 to about 10 ⁇ m in water by wet grinding or milling.
- a preferred dispersant may be a sodium lignosulfonate.
- the surfactant composition and the anthraquinone dispersion may be added separately to the cooking vessel, it is preferred that they be combined prior to such addition and then added as a single aqueous blend.
- the surfactant microemulsion serves to coat the anthraquinone particles and allows the mixture of anthraquinone and pulping liquors to penetrate the wood chips at a faster rate and saturate them more efficiently and completely. It is envisioned that it is this mechanism which results in obtaining the desired kappa number and lower rejects using significantly less anthraquinone.
- Sample A oleyl alcohol ethoxylate - 23 moles EO 20 parts by weight ricinoleic acid triglyceride etholxylate 60 parts by weight water 20 parts by Weight
- Sample B oleyl alcohol etholxylate - 23 moles EO 40 parts by weight ricinoleic acid triglyceride ethoxylate 40 parts by weight water 20 parts by weight
- Sample C oleyl alcohol ethoxylate - 23 moles EO 60 parts by weight ricinoleic acid triglyceride ethoxylate 20 parts by weight water 20 parts by weight
- Each sample was diluted to 12.5 wt% with water and heated to 82°C (180°F). At ambient temperature all diluted samples gave transparent solutions, and at 82°C (180°F) each sample turned a hazy bluish color.
- Example 1 The process of Example 1 was again conducted; except, in place of the 0.08% anthraquinone, 0.06% by weight based on oven dried wood chips of a digestion aid comprised of the surfactant blend of Sample A from Example 2 and anthraquinone was added to the white liquor as the white liquor was simultaneously pumped into the digester while the wood chips were being added. Upon completion of the digestion cycle, a pulp having a kappa number of 90 was produced with rejects of under 10%.
- a digestion aid comprised of the surfactant blend of Sample A from Example 2 and anthraquinone was added to the white liquor as the white liquor was simultaneously pumped into the digester while the wood chips were being added.
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- Paper (AREA)
Abstract
Description
Sample A: | |
oleyl alcohol ethoxylate - 23 moles EO | 20 parts by weight |
ricinoleic acid triglyceride etholxylate | 60 parts by weight |
water | 20 parts by Weight |
Sample B: | |
oleyl alcohol etholxylate - 23 moles EO | 40 parts by weight |
ricinoleic acid triglyceride ethoxylate | 40 parts by weight |
water | 20 parts by weight |
Sample C: | |
oleyl alcohol ethoxylate - 23 moles EO | 60 parts by weight |
ricinoleic acid triglyceride ethoxylate | 20 parts by weight |
water | 20 parts by weight |
Claims (25)
- An improved wood pulping aid composition comprising a cyclic keto compound for addition to pulping liquors in the delignification of lignocellulosic raw material characterized in that it comprises the addition of a surfactant mixture comprising at least one alkyl alcohol alkoxylate and at least one polyoxyalkylene glycol ether of an ester of an acid selected from the group consisting of ricinoleic acid and 12-hydroxystearic acid.
- The improved composition of claim 1 wherein the alkyl alcohol alkoxylates are prepared by reacting one or more C4-C30 alkyl alcohols with a member of the group of oxides consisting of ethylene oxide, propylene oxide, butylene oxide, and any combination thereof.
- The improved composition of claim 2 wherein the C4-C30 alkyl alcohols are derived from coconut oil, palm kernel oil, and petroleum.
- The improved composition of any one of claims 1 to 3, wherein the polyoxyalkylene glycol ether of an ester of an acid selected from the group consisting of ricinoleic acid and hydroxy stearic acid is prepared by reacting an ester of a glycol selected from the group consisting of glycerine, neopentyl glycol, trimethylolethane, trimethylolpropane, pentaerythritol and its polymers, mannitol, and sorbitol, with from about 5 moles to about 100 moles of an alkylene oxide selected from the group of ethylene oxide, propylene oxide, butylene oxide, and any combination thereof.
- The improved composition of any one of claims 1 to 4, wherein the reduction in the amount of the cyclic keto compound required is up to 50%.
- The improved composition of any one of claims 1 to 5, wherein the reduction in the amount of the cyclic keto compound required is up to 25%.
- The improved composition of any one of claims 1 to 6, wherein the cyclic keto compound is selected from the group of compounds consisting of naphthoquinone, anthraquinone, anthrone, phenanthrenequinone, the alkyl, alkoxy, and amino derivatives of said quinones, 6,11-dioxo-1H-anthra [1,2-c]pyrazole, anthraquinone-1,2-naphthacridone, 7,12-dioxo-7,12-dihydroanthra[1,2-b]pyrazine, 1,2-benzanthraquinone, and 10-methylene anthrone.
- The improved composition of any one of claims 1 to 7, wherein the cyclic keto compound and the surfactant mixture are introduced to the alkaline pulping liquor simultaneously via an aqueous blend in a ratio of from 10:1 to 1:10, respectively.
- The improved composition of any one of claims 2 to 8, wherein the C4-C30 alkyl alcohols are selected from the group consisting of primary alcohols and secondary alcohols having a linear or branched chain, and a combination thereof.
- The improved composition of any one of claims 2 to 9, wherein the member is reacted in an amount of from 5 to 100 moles.
- The improved composition of any one of claims 2 to 10, wherein the member is ethylene oxide.
- The improved composition of any one of claims 1 to 11, wherein the alkaline pulping liquor comprises sodium hydroxide, sodium carbonate, and sodium sulfide.
- An improved process for the delignification of lignocellulosic raw material in the production of cellulose pulps suitable for use in the manufacture of paper or paperboard comprising treating the lignocellulosic raw material in a closed reaction vessel with an alkaline pulping liquor with an amount of a cyclic keto compound included therein to achieve a determined pulp yield, characterized in that it comprises providing a reduction in the amount of the cyclic keto compound required to achieve said yield by adding to said alkaline pulping liquor a surfactant mixture comprising at least one alkyl alcohol alkoxylate and at least one polyoxyalkylene glycol ether of an ester of an acid selected from the group consisting of ricinoleic acid and 12-hydroxystearic acid.
- The improved process of claim 13 wherein the alkyl alcohol alkoxylates are prepared by reacting one or more C4-C30 alkyl alcohols with a member of the group of oxides consisting of ethylene oxide, propylene oxide, butylene oxide, and any combination thereof.
- The improved process of claims 13 or 14, wherein the C4-C30 alkyl alcohols are derived from coconut oil, palm kernel oil, and petroleum.
- The improved process of claim 13 wherein the polyoxyalkylene glycol ether of an ester of an acid selected from the group consisting of ricinoleic acid and 12-hydroxystearic acid is prepared by reacting an ester of a glycol selected from the group consisting of glycerine, neopentyl glycol, trimethylolethane, trimethylolpropane, pentaerythritol and its polymers, mannitol, and sorbitol, with from about 5 moles to about 100 moles of an alkylene oxide selected from the group of ethylene oxide, propylene oxide, butylene oxide, and any combination thereof.
- The improved process of any one of claims 13 to 16, wherein the reduction in the amount of the cyclic keto compound required is up to 50%.
- The improved process of any one of claims 13 to 17, wherein the reduction in the amount of the cyclic keto compound required is up to 25%.
- The improved process of any one of claims 13 to 18, wherein the cyclic keto compound is selected from the group of compounds consisting of naphthoquinone, anthraquinone, anthrone, phenanthrenequinone, the alkyl, alkoxy, and amino derivatives of said quinones, 6,11-dioxo-1H-anthra [1,2-c]pyrazole, anthraquinone-1,2-naphthacridone, 7,12-dioxo-7,12-dihydroanthra[1,2-b]pyrazine, 1,2-benzanthraquinone, and 10-methylene anthrone.
- The improved process of any one of claims 13 to 19, wherein the cyclic keto compound and the surfactant mixture are introduced to the alkaline pulping liquor simultaneously via an aqueous blend in a ratio of from 10:1 to 1:10, respectively.
- The improved process of any one of claims 14 to 20, wherein the C4-C30 alkyl alcohols are selected from the group consisting of primary alcohols and secondary alcohols having a linear or branched chain, and a combination thereof.
- The improved process of any one of claims 14 to 21, wherein the member is reacted in an amount of from 5 to 100 moles.
- The improved process of any one of claims 14 to 22, wherein the member is ethylene oxide.
- The improved process of any one of claims 13 to 23, wherein the alkaline pulping liquor comprises sodium hydroxide, sodium carbonate, and sodium sulfide.
- Use of a surfactant mixture comprising at least one alkyl alcohol alkoxylate and at least one polyoxyalkylene glycol ether of an ester of an acid selected from the group consisting of ricinoleic acid and 12-hydroxystearic acid as an additive to an alkaline pulping liquor, preferably in combination with a cyclic keto compound to reduce the amount required of said cyclic keto compound, preferably, said surfactant mixture and said cyclic keto compound are as defined in any one of claims 1 to 11 and said alkaline pulping liquor is as defined in claim 12.
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US814375 | 1991-12-26 | ||
US08/814,680 US5871663A (en) | 1997-03-11 | 1997-03-11 | Additive composition for reducing anthraquinone requirements in pulping of lignocellulosic material |
US08/814,375 US5871614A (en) | 1997-03-11 | 1997-03-11 | Process for reducing anthraquinone requirements in pulping of lignocellulosic material |
US814680 | 1997-03-11 |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0864689A2 true EP0864689A2 (en) | 1998-09-16 |
EP0864689A3 EP0864689A3 (en) | 1999-06-16 |
Family
ID=27123839
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP98400568A Withdrawn EP0864689A3 (en) | 1997-03-11 | 1998-03-11 | Additive composition and process for reducing anthraquinone requirements in pulping of lignocellulosic material |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP0864689A3 (en) |
CA (1) | CA2231313C (en) |
NO (1) | NO980659L (en) |
TW (1) | TW402652B (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2008058003A2 (en) | 2006-11-03 | 2008-05-15 | Nalco Company | Method and composition for improving fiber quality and process efficiency in mechanical pulping |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4481073A (en) * | 1980-12-01 | 1984-11-06 | Kawasaki Kasei Chemicals Ltd. | Process for removing anthraquinone type scale |
US5032224A (en) * | 1989-03-27 | 1991-07-16 | Exxon Chemical Patent Inc. | Method of producing pulp |
US5298120A (en) * | 1992-06-09 | 1994-03-29 | Michael Blackstone | Composition for enhancing the pulping of wood chips |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS6011895B2 (en) * | 1980-05-15 | 1985-03-28 | 日本蒸留工業株式会社 | Easily dispersible quinone composition and method for producing the same |
JP3304145B2 (en) * | 1992-05-18 | 2002-07-22 | 日本蒸溜工業株式会社 | Pulp cooking aid composition |
-
1998
- 1998-02-17 NO NO980659A patent/NO980659L/en not_active Application Discontinuation
- 1998-03-05 CA CA002231313A patent/CA2231313C/en not_active Expired - Fee Related
- 1998-03-11 EP EP98400568A patent/EP0864689A3/en not_active Withdrawn
- 1998-09-07 TW TW087114856A patent/TW402652B/en not_active IP Right Cessation
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4481073A (en) * | 1980-12-01 | 1984-11-06 | Kawasaki Kasei Chemicals Ltd. | Process for removing anthraquinone type scale |
US5032224A (en) * | 1989-03-27 | 1991-07-16 | Exxon Chemical Patent Inc. | Method of producing pulp |
US5298120A (en) * | 1992-06-09 | 1994-03-29 | Michael Blackstone | Composition for enhancing the pulping of wood chips |
Non-Patent Citations (2)
Title |
---|
DATABASE WPI Section Ch, Week 8204 Derwent Publications Ltd., London, GB; Class A97, AN 82-06736E XP002100591 & JP 56 161345 A (NIPPON JORYU KOGYO KK) , 11 December 1981 * |
DATABASE WPI Section Ch, Week 9410 Derwent Publications Ltd., London, GB; Class A97, AN 94-080431 XP002100592 & JP 06 033386 A (NIPPON JORYU KOGYO KK) , 8 February 1994 * |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2008058003A2 (en) | 2006-11-03 | 2008-05-15 | Nalco Company | Method and composition for improving fiber quality and process efficiency in mechanical pulping |
EP2082093A2 (en) * | 2006-11-03 | 2009-07-29 | Nalco Company | Method and composition for improving fiber quality and process efficiency in mechanical pulping |
EP2082093A4 (en) * | 2006-11-03 | 2010-08-04 | Nalco Co | Method and composition for improving fiber quality and process efficiency in mechanical pulping |
Also Published As
Publication number | Publication date |
---|---|
CA2231313A1 (en) | 1998-09-11 |
EP0864689A3 (en) | 1999-06-16 |
TW402652B (en) | 2000-08-21 |
NO980659L (en) | 1998-09-14 |
CA2231313C (en) | 2004-06-29 |
NO980659D0 (en) | 1998-02-17 |
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