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 a process for the production of pulp. More particularly, the invention relates to a process for the production of pulp from lignocellulosic materials by carrying out the cooking in the presence of a small amount of a novel type of cooking aid selected from the group consisting of hydroxyanthracenes and derivatives thereof.
• the cooking aid can be added to a cooking liquor in any of the conventional alkaline or sulfite or the like cooking processes.
• alkaline cooking process or simply “alkaline process” herein used includes various alkaline cooking processes such as a kraft process, a soda process, a sodium carbonate process and the like.
• sulfite cooking process or simply “sulfite process” herein used includes various sulfite cooking processes such as an alkaline sulfite process, a neutral sulfite process, a bisulfite process, and the like.
• the object of the present invention is to provide a novel process for the production of pulp free from the disadvantages mentioned above.
• the novel process of the present invention is characterized by the selective use of a specific type of a cooking aid comprising at least a member selected from the group consisting of hydroxyanthracenes and derivatives thereof. More particularly, in one aspect of the present invention, there is provided a process for producing alkaline pulp by carrying out the cooking of lignocellulosic materials such as wood, bagasse, hemp and the like in an alkaline cooking liquor in the presence of a small amount of hydroxyanthracene or a derivative thereof which is added as a novel type of cooking aid.
• a process for producing sulfite pulp by carrying out the cooking of said lignocellulosic materials in a cooking liquor comprising sulfite in the presence of a small amount of the same cooking aid as mentioned above.
• hydroxyanthracene or a derivative thereof added to the cooking liquor functions as a cooking aid to promote the dissolution of lignin into the cooking liquor as well as to prevent the degradation of cellulose and hemicellulose throughout the cooking treatment.
• this novel cooking aid the cooking yield and also the quality of the resulting pulp are improved, and the rate of cooking is increased. Incidental to the increased rate of cooking, the amounts of cooking chemicals and steam required for heating are also substantially reduced.
• Typical compounds which can be advantageously employed as said cooking aid in the practice of the present invention include hydroxyanthracenes and derivatives thereof having the following general formula: ##STR1## wherein m is 0, 1 or 2, n is 1 or 2, R is COOA, SO 3 A or H, and A is H or Na; providing that
• R when m is 1, R is at least one of COOA or SO 3 A and R cannot attach to (substitute on) the middle ring;
• R is H
• the compounds defined by the above general formula include those wherein R represents H, COOX wherein X is H or Na, or SO 3 Y wherein Y is H or Na; A represents H or Na; m represents 0, 1 or 2; and n represents 1 or 2.
• R represents H in the above general formula refers to a case in which at least one carbon atom in the anthracene nucleus loses its double bond to change from CH to CH 2 in the same position.
• the compounds defined by the above general formula include those obtained by the addition of at least one hydrogen atom to the carbon atom in the anthracene nucleus to have it lose its double bond and change from its CH form to CH 2 form in the same position.
• These compounds generally include dihydroxyanthracene, dihydroxydihydroanthracene, .[.carboxydihydroanthracene.]., .Iadd.carboxydihydroxyanthracene.Iaddend., as well as .[.dihydroanthracenesulfonic.]. .Iadd.dihydroxyanthracene sulfonic .Iaddend.acids including their sodium salts, dihydroxyanthracene carboxylic acids including their sodium salts, which are most advantageously employed in the practice of the present invention.
• the compounds Nos. 1, 2 and 9 are particularly preferred as the cooking aid in the present invention.
• novel cooking aid compounds are preferably used in an amount in the region of 0.005-3% by weight based on the bone dry weight of the raw material chips or the lignocellulosic materials to be added to the cooking liquor. If the compound is used in an amount in the region of 0.01-0.1% by weight based on the same standard, optimum results will be obtained.
• the compounds represented by the general formula, such as dihydroxyanthracenes, can easily be synthesized from naphthoquinone and butadiene by making use of Diels-Alder reaction.
• the preparation of these compounds is illustrated by the known preparations of Compounds 1-12, as follows.
• Compound (1) can be prepared as afore-described from naphthoquinone and butadiene by the Diels-Alder reaction. This process is disclosed on page 2, left column, lines 27-32 of U.S. Pat. No. 1,890,040.
• Compound (2) can be prepared by the process as disclosed on page 277 of Elsevier's Encyclopedia of Organic Chemistry, Volume 13.
• Compound (3) can be prepared by the process as disclosed on page 278 of the same reference identified in (b).
• Compound (11) can be prepared by the process as disclosed on page 650 of the same reference identified in (b).
• Compound (12) can be prepared by the process as disclosed on page 703 of the same reference identified in (b).

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• Paper (AREA)
• Polysaccharides And Polysaccharide Derivatives (AREA)
• Materials For Medical Uses (AREA)

Applications Claiming Priority (2)

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Publications (1)

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Family Applications (1)

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Citations (9)

Family Cites Families (7)

• 1976
  • 1976-12-10 JP JP14849276A patent/JPS5374101A/ja active Granted
• 1977
  • 1977-11-21 NZ NZ185734A patent/NZ185734A/xx unknown
  • 1977-11-23 AU AU30870/77A patent/AU513517B2/en not_active Expired
  • 1977-11-23 SE SE7713266A patent/SE437171B/xx not_active IP Right Cessation
  • 1977-11-28 NO NO774067A patent/NO150087C/no unknown
  • 1977-11-30 CA CA292,069A patent/CA1106557A/en not_active Expired
  • 1977-12-02 FI FI773661A patent/FI68868C/fi not_active IP Right Cessation
  • 1977-12-09 BR BR7708218A patent/BR7708218A/pt unknown
  • 1977-12-09 FR FR7737226A patent/FR2373637A1/fr active Granted
  • 1977-12-09 DE DE2754991A patent/DE2754991C3/de not_active Expired
• 1981
  • 1981-02-12 US US06/233,962 patent/USRE32943E/en not_active Expired - Lifetime

Patent Citations (9)

Non-Patent Citations (2)

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