Organic Patents (Class 162/72)
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Patent number: 5196069Abstract: A method for pretreating a cellulosic waste product with microwaves is disclosed as well as a method and apparatus for converting cellulosic wastes into soluble saccharides. The invention greatly enhances a reaction rate for enzymatic hydrolysis. A feed mixture of cellulose, water and acetic acid are irradiated with microwaves at a superatmospheric pressure in an autoclave reaction vessel and the treated cellulose is enzymatically hydrolyzed in a bioreactor. The acid and enzymes are optionally separated for reuse. As a feed stock for the culture of microbes, the sugars can be further processed into ethanol or food protein. High yield, low hazard potential, low energy usage and ready preparation in space of acetic acid and the enzyme makes the present invention well suited for use on long duration space missions.Type: GrantFiled: July 5, 1991Date of Patent: March 23, 1993Assignee: The United States of America as represented by the United States National Aeronautics and Space AdministrationInventors: Hatice S. Cullingford, Clifford E. George, George R. Lightsey
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Patent number: 5194388Abstract: Instruments for determining the degree of delignification corresponding to a sample of kraft or soda process digested wood pulp are calibrated with a predetermined quantity of refined lignin. For convenient use and application, a standardized solution comprising such refined lignin and an organic solvent such as ethylene glycol may be prepared for distribution to use points. Such standardized refined lignin, whether tested as a powdered solid or as a standardized solution yields a consistent "K" Number, "Permanganate" Number, "Kappa" Number or "Klason" Number value from standardized titration test procedures.Type: GrantFiled: July 10, 1989Date of Patent: March 16, 1993Assignee: Westvaco CorporationInventor: James J. Foster
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Patent number: 5188707Abstract: A method of hardening wood using a pulping agent for the chemical separation of lignin from cellulose in the wood without damage to either component. The pulping agent comprises the reaction product of (a) a compound produced by electrolytic oxidation of a predetermined amount of a loweralkanolamine in aqueous solution and neutralized with a strong mineral acid, with (b) the loweralkanolamine used in excess relative to the predetermined amount of loweralkanolamine subjected to the electrolytic oxidation. Also disclosed are processes utilizing such a pulping agent for chemically debarking whole logs as well as for converting soft wood into hard wood.Type: GrantFiled: December 26, 1991Date of Patent: February 23, 1993Inventor: John Gordy
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Patent number: 5182161Abstract: There is disclosed a support for photosensitive materials which comprises base paper comprising natural kraft pulp, and a resin layer formed on the base paper, said natural kraft pulp being produced by digesting wood chips by the kraft process, and washing the digested product in the presence of an anti-foaming agent or a foam-inhibitor, followed by bleaching by the use of chlorine or an oxidizing agent containing at least one chlorine atom, and said natural kraft pulp having a number of areas tarnished by silver tarnishing reaction of 20 or less. This support exhibits good photographic properties when a silver halide photosensitive layer is provided thereon.Type: GrantFiled: July 9, 1991Date of Patent: January 26, 1993Assignee: Mitsubishi Paper Mills LimitedInventors: Touru Noda, Masayuki Tsubaki, Yasunosuke Sakai, Tetsuya Ashida, Hiroshi Matsuda
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Patent number: 5178762Abstract: A method for oxidizing organic and/or heavy metal contaminants in wastewaters, sludges, or soils containing such contaminants by contacting the wastewaters, sludges, or soils with soybean peroxidase and a peroxide.Type: GrantFiled: April 29, 1992Date of Patent: January 12, 1993Assignee: The Mead CorporationInventors: Alexander R. Pokora, Mark A. Johnson
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Patent number: 5169497Abstract: A process for improving freeness of paper pulp which comprises these steps:a) Adding to the pulp at least 0.05% based on the dry weight of the pulp, of a cellulolytic enzyme;b) Allowing the pulp to contact the cellulolytic enzyme for at least 20 minutes at a temperature of at least 20.degree. C.;c) Adding at least 0.0007% based on the dry weight of the pulp of a water soluble cationic polymer, and thend) Forming the thus treated pulp into paper.Type: GrantFiled: October 7, 1991Date of Patent: December 8, 1992Assignee: Nalco Chemical CompanyInventors: Jawed M. Sarkar, David R. Cosper
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Patent number: 5145558Abstract: A composition for alkaline hydrogen peroxide bleaching of mechanical wood pulp which employs a quaternary amine compound, such as (3-chloro-2-hydroxy-propyl) trimethyl ammonium chloride, in the stabilized bleach solution. The brightness of the final paper product made from such bleached pulp shows marked improvement over that in which only chelating agents are employed to improve the brightness according to the known art. The process is useful in both silicate and silicate-free bleach solutions.Type: GrantFiled: February 15, 1991Date of Patent: September 8, 1992Assignee: The Dow Chemical CompanyInventors: Steven H. Christiansen, Teresa Littleton, Robert T. Patton
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Patent number: 5143581Abstract: A process for the manufacture of high-yield pulps bleached with the aid of hydrogen peroxide in alkaline medium, which consists in subjecting the pulp to be bleached successively to:(a) a pretreatment with the aid of a sequestering agent for metal ions, followed by a washing operation,(b) a treatment with sulphite and a reducing agent which is more electronegative than the sulphite ion, which act together and in a medium of initial pH between 7 and 12.5, followed by a washing operation to remove the sulphite ions and the reducing agent, and(c) to a bleaching treatment with the aid of hydrogen peroxide in alkaline medium in the presence of a quantity of silicate of between 0% and 1%.Type: GrantFiled: March 6, 1991Date of Patent: September 1, 1992Assignee: AtochemInventor: Michel Devic
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Patent number: 5139617Abstract: A process for the production of a hemicellulose hydrolysate and special pulp through two steps, the first step comprising the prehydrolysis of the material and the second step the dissolving of the lignin contained in the prehydrolyzed material. According to the process the lignin dissolving is carried out by neutral sulphite cooking with anthraquinone or a derivative thereof as a catalyst, the pH of the cooking liquor being initially at least 10.Type: GrantFiled: June 8, 1990Date of Patent: August 18, 1992Assignee: Suomen Sokeri OyInventors: Panu O. Tikka, Nils E. Virkola
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Patent number: 5127993Abstract: The present invention is directed to the use of certain ethoxylated compounds to increase the yield of green liquor semi-chemical pulping processes, the compound have the following structures: ##STR1##Type: GrantFiled: January 10, 1990Date of Patent: July 7, 1992Assignee: Betz PaperChem, Inc.Inventor: Cheng-I Chen
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Patent number: 5116474Abstract: A process for treating paper pulp using an enzyme composition. An enzyme composition containing cellulases or hemicellulases selected from among those derived from the fungus Humicola insolens and from the bacterium Cellulomonas is made to act upon an aqueous suspesnion of the pulp possessing a given Schopper-Riegler level (SR) according to Standard NFQ 50 003. This procedure is particularly useful for treating a recycled fiber-based paper pulp having a pH of at least 5.Type: GrantFiled: October 1, 1990Date of Patent: May 26, 1992Assignee: LA Cellulose Du PinInventors: M. Jean-Luc Fuentes, M. Christian Rousset, M. Gerard Goma, M. Jean-Claude Pommier
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Patent number: 5110412Abstract: The machinability of a papermaking composition of recycled fibers is improved by treating the fibrous composition with an enzyme preparation which acts on all or part of the cellulose fiber components, causing an improvement in the drainability of the water through the fibrous layer.Type: GrantFiled: February 11, 1991Date of Patent: May 5, 1992Assignee: La Cellulose Du PinInventors: Jean-Luc M. Fuentes, Michel M. Robert
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Patent number: 5080754Abstract: A method and article of manufacture thereof is provided for reducing brightness reversion in bleached lignin-containing pulps or newsprint by the treatment of the bleached lignin-containing pulp or newsprint with a compound which donates a hydrogen atom to a photo-excited group or free radical more easily than does the lignin contained in the treated pulp. The hydrogen donating compounds include compounds with certain formyl functionality, including formate salts such as sodium, magnesium and calcium formate, formamides, formic acid esters, and formylurea. In one embodiment, calcium carbonate is added to enhance the activity of the formyl compound. The further addition of a trace amount of superoxide anion quencher such as copper sulfate or ascorbic acid is also provided to still further enhance the activity of the formyl compound, especially formate salts.Type: GrantFiled: July 20, 1990Date of Patent: January 14, 1992Assignee: The Research Foundation of State University of NYInventors: Raymond C. Francis, Carlton W. Dence, Thomas C. Alexander
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Patent number: 5074961Abstract: The invention is a process for controlling pitch deposition from pulp in papermaking systems, by an effective amount of a polymer having methyl ether groups pendant to the backbone of the polymer to the pulp term "polymer". A preferred embodiment of the invention is controlling pitch deposition by adding an effective amount of a water soluble cellulose ether.Type: GrantFiled: July 17, 1989Date of Patent: December 24, 1991Assignee: Betz Laboratories, Inc.Inventors: David D. Dreisbach, Gilbert S. Gomes
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Patent number: 5068009Abstract: Fluff pulp with improved defibration properties is produced by exposing the pulp to an enzyme treatment at any stage during the pulp production process. The enzyme treatment may be carried out using an enzyme preparation containing cellulolytic and/or hemicellulolytic activity. The enzyme treated fluff pulp is useful in the manufacture of disposable hygiene products and air-laid products.Type: GrantFiled: March 22, 1990Date of Patent: November 26, 1991Assignee: Cultor Ltd.Inventors: Olli Jokinen, Jukka Kettunen, Jarkko Lepo, Tapio Niemi, Jaakko E Laine
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Patent number: 5055159Abstract: A method of using biological processes as a pretreatment step in combined biological and mechanical paper pulping process is described. The process uses a species of fungus, Ceriporiopsis subvermispora, which has not previously been used for this purpose. It has been found that even with a non-optimized system, and with the stationary holding of the wood chips during fungal incubation, that significant savings in energy usage in the pulping process can be achieved compared to conventional mechanical pulping while simultaneously achieving increased strength characteristics in the paper.Type: GrantFiled: May 16, 1990Date of Patent: October 8, 1991Assignee: Wisconsin Alumni Research FoundationInventors: Robert A. Blanchette, Gary F. Leatham, Michael Attridge, Masood Akhtar, Gary C. Myers
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Patent number: 5049236Abstract: A method for the preparation of a mixture of fused ring quinone type compounds from lignin and lignin-derived substances. The mixture of fused ring quinone compounds has been found useful in the wood pulping process as an accelerator in the degradation and separation of wood lignin from the other principal wood constituents, cellulose and hemicellulose.Type: GrantFiled: August 23, 1988Date of Patent: September 17, 1991Assignee: Institute of Paper Science and Technology, Inc.Inventors: Donald R. Dimmel, John C. Wozniak
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Patent number: 5041192Abstract: An improved wood pulping process for the delignification of wood in a solvent wherein the solvent is a supercritical fluid under supercritical conditons and contains a delignification agent such as sodium hydroxide, sodium sulfide and/or sodium bisulfate.Type: GrantFiled: September 16, 1988Date of Patent: August 20, 1991Assignee: University of South FloridaInventors: Aydin K. Sunol, Shan L. Chen
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Patent number: 5035772Abstract: A method for treating lignin containing pulp, subsequent to being bleached by:a) always treated with at least one chemical, which chemically reduces .alpha.-carbonyl and .gamma.-carbonyl groups in the lignin; and in at least one further step isb) treated with at least one chemical, which will block the phenolic hydroxyl groups of the lignin and/orc) supplied with at least one chemical, which will convert short-wave light quanta to long-wave light quanta.According to a preferred embodiment of the invention cellulose pulp is subjected to all of the above treatment processes, i.e. a)+b)+c) and is washed after the two initial treatment stages. The method solves the problem of yellowing of lignin containing pulps, e.g. high yield pulp.Type: GrantFiled: September 28, 1989Date of Patent: July 30, 1991Assignee: Mooch Domsjo ABInventors: Roland A. Agnemo, Birgitta E. Lunden-Lundgren
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Patent number: 5032224Abstract: Alkaline pulping (such as Kraft) processes for various lignocellulosic materials, such as coniferous or disiduous wood chips, into pulp is improved by adding relatively small amounts of a digestive additive selected from the group consisting essentially of anionic surfactants, nonionic surfactants, and anionic/nonionic surfactant blends, such as sodium alpha-sulfo methyl laurate, cocodiethanolamide, butyl ethylenoxide-propylenoxide block copolymers, etc. to the alkaline cooking media to obtain pulps having a select Kappa number range with a reduction in pulp material reject percentage, a reduction of H-factor, a reduction of white liquor requirements and a reduction of cooking time period, relative to H-factor, reject percentages, white liquor requirements and digestion periods experienced in similar alkaline digestion processes without the inventive digestive additive.Type: GrantFiled: March 27, 1989Date of Patent: July 16, 1991Assignee: Exxon Chemical Patent Inc.Inventor: Madhu R. Ahluwalia
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Patent number: 5013404Abstract: A process for alkaline hydrogen peroxide bleaching of mechanical wood pulp which employs a quaternary amine compound, such as (3-chloro-2-hydroxypropyl)trimethyl ammonium chloride, in the stabilized bleach solution. The brightness of the final paper product made from such bleached pulp shows marked improvement over that in which only chelating agents are employed to improve the brightness according to the known art. The process is useful in both silicate and silicate-free bleach solutions.Type: GrantFiled: November 15, 1989Date of Patent: May 7, 1991Assignee: The Dow Chemical CompanyInventors: Steven H. Christiansen, Teresa Littleton, Robert T. Patton
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Patent number: 5002634Abstract: A method for the preparation of a mixture of fused ring quinone type compounds from lignin and lignin derived substances. The mixture of fused ring quinone compounds has been found useful in the wood pulping process as an accelerator in the degradation and separation of wood lignin from the other principal wood constituents, cellulose and hemicellulose.Type: GrantFiled: September 25, 1989Date of Patent: March 26, 1991Assignee: Institute of Paper Science and Technology, Inc.Inventors: Donald R. Dimmel, John C. Wozniak
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Patent number: 4992308Abstract: Method and process using a supercritical fluid, with or without the aid of entrainers (1) to solubilize a monomer, monomer mixture or polymer which may or may not include additives and entrainers, (2) to carry the supercritical solvent mixture thereby created into the wood matrix, (3) to remove extractives from the wood, (4) to precipitate the monomer or polymer within the wood, and (5) to polymerize the monomer in situ in the wood.Type: GrantFiled: September 16, 1988Date of Patent: February 12, 1991Assignee: University of South FloridaInventor: Aydin K. Sunol
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Patent number: 4966650Abstract: The chemical components of lignocellulosic material which have been dissociated by a steam explosion process can be extracted from the mixture of components using a solvent extraction process. The solvents are water, alcohol and a mild caustic in that order, or the alcohol step can be by-passed and only water and caustic are used. The caustic is a stronger solvent and it will extract the alcohol solubles along with the caustic only solubles. The eluant from the these extractions contains a range of lignin derived substances, which have different applications, such as thermoplastic and thermosetting characteristics. This invention describes a method for partitioning these lignin components into reproducible fractions having definable characteristics for particular applications. For instance, many copolymer applications require a thermosetting only fraction of the lignin. Other applications require a thermoplastic only lignin.Type: GrantFiled: September 19, 1988Date of Patent: October 30, 1990Inventors: Edward A. DeLong, George S. Ritchie
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Patent number: 4960540Abstract: The present invention involves new anti-foam compositions which control foaming in aqueous systems and by nature of their inverse cloud point characterisitics are insoluble and particulate above their inverse cloud point, and soluble below it. This property makes them particulate non-depositing defoamers. As the defoamed aqueous system cools down these novel products become soluble, preventing insoluble material (pitch) from depositing on process equipment and matter being processed. The anitfoam composition is an alkoxylated bis-amide of the following formula: ##STR1## where R.sup.1 is ##STR2## R.sup.2 is --(CH.sub.2).sub.a --; R.sup.3 is alkyl C.sub.12 to C.sub.20 ; ##STR3## x,y,z are each independently integers from 0 to 20; a is an integer from 1 to 5;c is an integer from 0 to 5;R.sup.5 is selected from H, CH.sub.3, C.sub.2 H.sub.5, C.sub.3 H.sub.6.Type: GrantFiled: August 24, 1989Date of Patent: October 2, 1990Inventors: Thomas C. Friel, Jr., Anthony J. O'lenick, Jr.
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Patent number: 4952277Abstract: A process for making paper and linerboard, employing certain nonionic surface active agents to increase the yield of kraft pulping. The surface active agents having the structural formula ##STR1## where n is an integer from 8 to 12, and x is a positive integer from 1 to about 100, the surface active agent being present in the cooking liquor in an amount effective to increase the yield of pulp.Type: GrantFiled: May 19, 1989Date of Patent: August 28, 1990Assignee: Bet PaperChem, Inc.Inventors: Cheng-I Chen, Theresa D. Hancock
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Patent number: 4941944Abstract: A method for the continuous countercurrent production of lignins and sugars from wood and other ligno cellulosic materials by organosolv delignification or saccharification at elevated temperatures and pressures is disclosed. The novel method comprises: (a) continuously introducing comminuted lignocellulose materials with a natural mositure content into a reaction vessel from one end; (b) continuously introducing a cooking liquor comprising a major proportion of organic solvent, a minor proportion of water, and a slight amount of inorganic acid countercurrently into the reaction vessel from the opposite end; (c) causing the comminuted lignocellulosic material to be contacted by the cooking liquor; and (d) continuously withdrawing cooking liquor from the reaction vessel after it has commingled with and has dissolved sugars and lignin and other substances from the comminuted lignocellulosic material.Type: GrantFiled: January 2, 1990Date of Patent: July 17, 1990Assignee: Pierre A. TonachelInventor: Robert P. Chang
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Patent number: 4938842Abstract: A process is provided for the bleaching of wood pulp with hydrogen or sodium peroxide. The process includes the steps of adding to a wood pulp a bleach liquor having an effective amount of hydrogen or sodium peroxide bleaching agent and, by weight of the diluted wood pulp, 0.5 to 6% sodium hydroxide, 0 to 5% sodium silicate, 0 to 1%, preferably 0.02 to 0.05%, magnesium sulphate, and a chelating agent in an amount sufficient to sequester heavy metal ions in the pulp, to produce a pulp consistency of 1 to 16% at a temperature in the range of the bleach liquor freezing point to 25.degree. C., uniformly mixing the bleach liquor with the wood pulp, and immediately thickening the diluted wood pulp to a consistency in the range of 20 to 70% for bleaching of the thickened wood pulp.Type: GrantFiled: February 23, 1989Date of Patent: July 3, 1990Assignee: Abitibi-Price Inc.Inventors: Philip Whiting, Adele M. Rhodes, Arnold E. Willoughby, Martin G. Fairbank, Hollis D. MacEwen, Fraser McLellan
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Patent number: 4923565Abstract: An enzyme preparation containing cellulases and/or hemicellulases is reacted on a homogeneous aqueous suspension of paper pulp having a Schopper-Riegler (SR) degree determined in accordance with standard NFQ 50 003 of at least equal to 25. A paper pulp based on recycled fibers is treated.Type: GrantFiled: September 22, 1987Date of Patent: May 8, 1990Assignee: La Cellulose Du PinInventors: Jean-Luc Fuentes, Michel Robert
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Patent number: 4908097Abstract: Disclosed are modified cellulosic fibers comprising the reaction product of linear, water-wettable polysaccharides with N,N'-methylenebisacrylamide and methods of making same. The materials are useful in the preparation of products characterized by their increased bulk and absorbency.Type: GrantFiled: October 26, 1988Date of Patent: March 13, 1990Assignee: Scott Paper CompanyInventor: Larry Box
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Patent number: 4906331Abstract: The present invention is directed to the use of certain ethoxylated compounds to increase the yield of chemical pulping processes, the compound have the following structures: ##STR1## These ethoxylated compounds have molecular weights of from about 500 to about 30,000 the (CH.sub.2 CH.sub.2 O) comprising from about 20 to 80 percent of the compound; and a, b, and c are each at least 1. The compounds are surface active agents which are added to the cooking liquor. The wood chips are cooked from about one-half and ten hours at a temperature of from about 200 and 500 degrees Fahrenhelt in a liquor including sodium hydroxide, sodium sulfide, and the surface active agent. The wood plug would have a reject level of at least 5% when the chips are cooked in the absence of the surface active agent. The process provides a simultaneous reduction in the level of rejects and an increased yield of pulp.Type: GrantFiled: April 12, 1988Date of Patent: March 6, 1990Assignee: Betz PaperChem, Inc.Inventors: Michael M. Blackstone, Cheng-I Chen, Thomas W. Woodward
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Patent number: 4895622Abstract: This invention relates to an improved press felt conditioning treatment which controls the deposition of polymerically flocculated particulate substances in a press felt. The treatment comprises applying to the felt an effective inhibiting amount of a conditioner comprising a relatively low molecular weight organic, anionic polymer and at least one hydrophilic, nonionic or anionic surfactant. The polymer preferrably has an acrylic acid or methacrylic acid functionality and is preferrably selected from the group consisting of homopolymers of acrylic acid, a methacrylic acid/polyethylene glycol allyl ether copolymer, a homopolymer of methacrylic acid, an acrylic acid/polyethylene glycol allyl ether copolymer, and an acrylic acid/1-allyloxy-2-hydroxypropane sulfonic acid copolymer.Type: GrantFiled: November 9, 1988Date of Patent: January 23, 1990Assignee: Betz Laboratories, Inc.Inventors: Daniel J. Barnett, Abdul Q. Khan, Patricia R. Keen
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Patent number: 4891096Abstract: The process for biochemical retting of phloem-fiber plants such as hemp, flax, ramie, jute, kenaf, etc. permits separation of the fibers of the bundle for subsequent utilization in the textile or paratextile industry. The process comprises treating the fibrous plants with at least one SPS-ase enzyme and preferably a mixture of enzymes comprising .beta.-glucanase, pectinase and SPS-ase.Type: GrantFiled: March 22, 1989Date of Patent: January 2, 1990Assignee: Comite Economique Agricole De La Production Du ChanvreInventor: Jean-Sony Akkawi
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Patent number: 4891320Abstract: A process for degrading environmentally persistent organic pollutant compounds by reacting those pollutant compounds with fungal enzymes containing a lignin-degrading enzyme and hydrogen peroxide. This reaction preferably takes place under aerobic conditions such that the organic pollutant compounds are degraded. Using the present invention, degradation to carbon dioxide and water is possible. Alternatively, the reaction may be halted to leave desirable reaction intermediates.The enzyme and hydrogen peroxide system of the present invention is found to be ideal for degrading various types of orgaic pollutants. Moreover, the reaction system is nonspecific. As a result, only a single type of fungus or fungus-generated enzyme system is required in order to degrade a wide spectrum of pollutants.One embodiment of the present invention relates to a preferred process where the enzyme (peroxidase) and hydrogen peroxide are provided by a lignin-degrading fungi or fungi mixed with the pollutant organic compound.Type: GrantFiled: April 19, 1988Date of Patent: January 2, 1990Assignee: Utah State University FoundationInventors: Steven D. Aust, John A. Bumpus, Ming Tien
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Patent number: 4872995Abstract: Methods of controlling the formation of calcium oxalate in aqueous systems are disclosed. The methods comprise adding from about 0.1 to 500 ppm of a water soluble (meth)acrylic acid/allyl ether copolymer to the desired water system. The methods are especially well adapted for use in pulping and paper making systems wherein calcium oxalate is often encountered as a troublesome scale forming compound.Type: GrantFiled: June 6, 1988Date of Patent: October 10, 1989Assignee: Betz Laboratories, Inc.Inventors: Fu Chen, Daniel L. Michalopoulos
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Patent number: 4871423Abstract: Compositions and a method are disclosed for minimizing brightness reversion of chromophore-containing wood pulps, especially low-cellulose wood pulps, such as groundwood and thermomechanical pulps, which have been reductively bleached or bleached with hydrogen peroxide. Ascorbic acid and palmitoyl ascorbate are particularly effective for preventing such reversion at low levels.Type: GrantFiled: August 10, 1987Date of Patent: October 3, 1989Assignee: Hoechst Celanese CorporationInventors: S. Allen Grimsley, James C. Robinson, Mark A. Schroeder
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Patent number: 4830708Abstract: There is provided a process for bleaching kraft hardwood pulp wherein the bleaching is done utilizing the fungus Coriolus versicolor wherein the pulp is treated with the fungus at a temperature and for a time sufficient for the bleaching to occur. The pulp may subsequently be sterilized after bleaching.Type: GrantFiled: November 30, 1987Date of Patent: May 16, 1989Assignee: Pulp and Paper Research Institute of CanadaInventors: Michael G. Paice, Frederick S. Archibald, Lubomir Jurasek, Robert E. Bourbonnais, Ka-Kee Ho
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Patent number: 4826567Abstract: Process for the delignification of cellulosic substances comprising:a first stage of treatment of cellulosic substances with an acida second stage of treatment with hydrogen peroxide in an alkaline mediuma third stage of digestion in the presence of at least one chemical reactant chosen from hydroxides of alkaline or alkaline-earth metals.The process applies to the treatment of wood fragments.Type: GrantFiled: March 27, 1987Date of Patent: May 2, 1989Assignee: Interox (Societe Anonyme)Inventor: Josef S. Gratzl
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Patent number: 4810328Abstract: An improved method of brown stock washing is disclosed. A nonionic surfactant in combination with a polyelectrolyte dispersant, and preferably a solvent, are utilized in the washing step in the pulping of virgin cellulosic fiber. The methods of the invention provide for the enhanced removal and recovery of cooking chemicals and organics from the pulp.Type: GrantFiled: November 4, 1987Date of Patent: March 7, 1989Assignee: Diamond Shamrock Chemicals CompanyInventors: Richard E. Freis, James E. Maloney, Thomas R. Oakes
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Patent number: 4804440Abstract: A multistage process for bleaching high-yield and ultra high-yield pulps is described whereby the pulp is treated sequentially with a peroxygen compound, a reducing compound and a final peroxygen compound to achieve higher brightness levels.Type: GrantFiled: March 15, 1988Date of Patent: February 14, 1989Assignee: Pulp and Paper Research Institute of CanadaInventors: Norman Liebergott, Cyril Heitner
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Patent number: 4790905Abstract: A process for preparing a cellulose paste by treatment of lignocellulose materials which comprises impregnating wood or vegetable shavings in divided form with an aqueous solution containing 2 to 20% by weight of alkaline metal hydroxides, alkali metal salts, or alkaline earth metal hydroxides, adjusting the weight of the solution retained by impregnation to a value representing 1 to 3 times the weight of treated material, the ratio of the weight of the impregnated mass to the dry weight of the lignocellulosic material being preferably not more than about 2.6:1, subjecting the impregnated masses to cooking treatment by exclusively indirect heating at a temperature varying from 150.degree. to 200.degree. C. without exerting any mechanical disintegrating action for a period varying from 15 to 60 minutes, and pressing the cooked product so as to extract therefrom the solubilized lignin in the form of a black liquor containing about 50% of dry material.Type: GrantFiled: October 10, 1986Date of Patent: December 13, 1988Assignee: Societe Tag Pulp Industries S.A.Inventors: Patrick M. F. Nivelleau de La Bruniere, Jean P. M. Galichon
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Patent number: 4787959Abstract: A process of preparing new chemical paper pulps wherein a first cooking stage is effected in the presence of sodium hydroxide and advantageously adjuvants, after which an intermediate grinding is effected and followed by a second cooking stage characterized in that the second cooking stage is performed in the presence of a peroxide alkaline solution containing a peroxide stabilizing agent.Type: GrantFiled: November 18, 1987Date of Patent: November 29, 1988Assignee: AtochemInventors: Dominique Lachenal, Christian de Choudens, Pierre Monzie
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Patent number: 4786365Abstract: A process of manufacturing cellulose pulp from wood by digesting the wood with sulphite cooking liquor containing additions of sulphide and in the presence of a quinone or hydroquinone compound. According to the invention, the mole ratio between sulphide and sulphite shall amount to 0.01-0.2, preferably 0.05.0.15, suitably 0.08-0.12.Type: GrantFiled: February 16, 1988Date of Patent: November 22, 1988Assignee: Svenska TraforskningsinstitutetInventors: Ants Teder, Leelo Olm, Jan-Erik Wilken
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Patent number: 4767500Abstract: A sulphite cooking process is described for the production of pulp from materials containing lignocelluloses, with recovery of the cooking chemicals, in which the cooking, the blowing, the washing and the bleaching are performed sucessively. The waste liquor is subjected to several thermal treatments for the recovery of the cooking chemicals. For the cooking of the lignocellulosic materials, alkaline sulphite solutions are used, to which one or, in mixture, several low-boiling solvents are added, as well as at least one compound suitable as a redox catalyst.Type: GrantFiled: August 27, 1987Date of Patent: August 30, 1988Assignee: Kraftanlagen AktiengesellschaftInventors: Rudolf Patt, Othar Kordsachia
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Patent number: 4765867Abstract: The invention relates to a process for controlling pitch deposition from pulp in papermaking systems which comprises adding to the pulp an effective amount of a water-soluble quaternized polyamine ionene polymer.Type: GrantFiled: July 2, 1986Date of Patent: August 23, 1988Assignee: Betz Laboratories, Inc.Inventors: David D. Dreisbach, Gilbert S. Gomes, Michael A. Schuster
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Patent number: 4764252Abstract: Lignocellulosic material is pulped by a process comprising the steps of: introducing a molecular oxygen-containing gas, such as air, into an alkaline sulfide solution containing NaOH, Na.sub.2 S and at least one cyclic organic compound selected from quinone, hydroquinone, 9,10-diketohydroanthracene and 9,10-dihydroxyhydroanthracene compounds, to oxidize at least a portion of Na.sub.2 S; delignifying the lignocellulosic material with an alkaline sulfide cooking liquor containing the oxidized alkaline sulfide solution at an elevated temperature and; then, recovering the resultant pulp from the delignification mixture.Type: GrantFiled: November 19, 1985Date of Patent: August 16, 1988Assignee: Oji Paper Co., Ltd.Inventors: Yoichi Shin, Isao Wada, Junichiro Kido, Shigeru Eimaeda
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Patent number: 4752354Abstract: A process for the oxidative or reductive bleaching of wood pulp, especially in the presence of heavy metal salts, in which a complex former combination containing at least one phosphonic acid, at least one polyhydroxycarboxylic acid and at least one phosphate or salts thereof is added to a wood pulp slurry in an amount of from 0.5 to 50%, based on the dry mass of the wood pulp, and subsequent bleaching is carried out in the presence of a reducing agent. Also provided is a complex former combination for use in the oxidative or reductive bleaching of wood pulp, comprising at least one phosphonic acid, at least one polyhydroxycarboxylic acid and at least one phosphate or salts thereof.Type: GrantFiled: July 21, 1986Date of Patent: June 21, 1988Assignee: Benckiser-Knapsack GmbHInventors: Harald Beurich, Margarete Scholl
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Patent number: 4746401Abstract: A process for the delignification of cellulosic materials, wherein a high-yield cellulose pulp and high-value by-product, such as reactive lignins of low molecular weight are produced, which comprises degassing lignocellulosic material, rapidly heating the lignocellulosic material in a liquor comprising water, an organic solvent and a buffer thereby maintaining a substantially neutral solvent extraction, such that said lignocellulosic material is cooked in the liquor as it is heated from a temperature of 150.degree. C. to a selected maximum temperature in the range of 200.degree. to 280.degree. C.; and rapidly cooling the mixture to a temperature less than 150.degree. C. The reaction is controlled to maximize reactive lignin solvation while suppressing cellulose degradation.Type: GrantFiled: January 6, 1986Date of Patent: May 24, 1988Assignee: Georgia Tech Research Corp.Inventors: Ronnie S. Roberts, John D. Muzzy, George S. Faass
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Patent number: RE32825Abstract: Reductive bleaching of lignin containing pulps employing polydentate ligand complexes of dipositive vanadium, chromium and titanium. High brightness pulps with good reversion stability are obtained. The process is essentially polution free as the reduced complexes can be repeatedly regenerated electrochemically.Type: GrantFiled: June 17, 1987Date of Patent: January 10, 1989Assignee: International Paper CompanyInventors: Michael N. Hull, Vacheslav M. Yasnovsky
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Patent number: RE32943Abstract: An improved process for the production of pulp from lignocellulosic material characterized by the employment of a cooking aid is disclosed. The cooking of the lignocellulosic material is carried out in the presence of a small amount of a compound selected from the group consisting of hydroxyanthracenes and derivatives thereof.Type: GrantFiled: February 12, 1981Date of Patent: June 6, 1989Assignee: Honshu Seishi Kabushiki KaishaInventors: Masato Nakamura, Yoshika Nomura, Iwahiro Uchimoto