Abstract: A process and composition especially suited for bleaching wood pulp characterized by the use of hypochlorous acid in combination with chlorine dioxide and/or a nitrogen compound having the characteristic of minimizing fiber degradation and enhancing fiber brightness. The preferred composition is in an aqueous solution adjusted to an optimum pH and is used as a direct replacement for conventional compositions so as to effect substantial savings in the costs of chemicals and energy per ton of bleached pulp.

Abstract: An improved method for deresination of wood chips or pulp is provided. The method comprises contacting the chips or pulp with an ethoxylated alkyl phenol deresinating composition during processing to reduce the level of natural resins present therein. The improvement comprises substituting a sufonated fatty acid for part of the ethoxylated alkyl phenol while maintaining substantially the same level of deresination.

Abstract: The use of primary and secondary amines and certain other compounds in ferricyanide assisted oxygen delignifying bleaching of lignocellulosic pulps permits more rapid removal of a desired amount of lignin from the pulp and, hence, the retention of higher pulp viscosity.

Abstract: A process for producing isopropyl alcohol and useful by-products from cellulosic substrates without utilizing toxic acids. This process comprises the steps of: (1) digesting cellulosic substrates in a heated solution of sodium carbonate; (2) digesting the cellulosic product of step (1) in a heated solution containing isopropyl alcohol or aluminum isopropylate together with sodium acetate and optionally, acetic acid, to produce a biomass and a black liquid of saturated acyclic hydrocarbons; (3) mixing the biomass of step (2) with amylolytic enzymes or with xylophagous bacteria to initiate fermentation of the biomass; (4) adding the black liquid of step (2) together with basic aluminate acetate and a mixture of formaldehyde and phenol or sulfonated phenol to the mixture of step (3) and heating the resulting mixture to a temperature ranging between 120.degree. to 160.degree. C. under a pressure ranging between 1.5 and 45 kg/cm.sup.2 until isopropyl alcohol is produced.

Abstract: A pulping liquor for the delignification of lignocellulosic materials is disclosed which avoids the use of sodium hydroxide and so avoids degradation of substantial portions of the cellulose component, and simultaneously avoids the use of sulphide or other environmental pollutants. The cooking process employing this liquor can advantageously include recycling of the liquor to provide sustained delignification from the same original liquor provided, and distillation of spent liquor to recover the essential components thereof.The liquor is comprised of alcohol, an amine and water, each present in amount of 1-12 parts by volume. The liquor is further used in the presence of a quinone and/or azine catalyst.

Abstract: High yield pulping is achieved by cooking a lignocellulosic material in a confined chamber in the absence of added oxygen at elevated temperatures up to 240.degree. C. with an initially neutral or acidic mixture of alcohol and water in volume ratio between 50:50 and virtually anhydrous alcohol cooking liquor, using a lower aliphatic alcohol namely methanol, ethanol or n-propanol, carrying in solution at least about 0.002 moles per liter of a magnesium, calcium or barium salt as a primary catalyst soluble in at least catalytic amounts in the mixture to form barium, calcium and magnesium ions. The cooking time may range from at least two (2) minutes to under three (3) hours. The process yields bright, free-fiber pulp even at residual lignin of 80 Kappa number as high as 80% of softwood and up to 75% of hardwood weight, of viscosity (TAPPI 0.5% Cu En) above 18 up to 60 centipoise. Addition of trace amounts of an acidic compound as a secondary catalyst increases the rate of delignification.

Abstract: An absorbent batt of non-delignified fibers is stabilized by applying a lignin solvent to an assemblage of such fibers to soften at least 10 percent of the fibers. When the fiber assemblage is compressed and the solvent is removed, the softened lignin of adjacent contacting fibers cause a lignin-to-lignin interfiber bond to occur at the fiber intersection.

Abstract: A process for the production of sugars, and optionally cellulose and lignin, from lignocellulosic vegetable materials which comprises subjecting the vegetable materials to a chemical pretreatment with a mixture of water and lower aliphatic alcohols and/or ketones at a temperature from 100.degree. to 190.degree. C. for a period of from 4 hours to 2 minutes with control of the breakdown of the hemicellulose components followed by separation of residue and a subsequent main chemical treatment with a similar solvent mixture at elevated temperatures for a further period of from 6 hours to 2 minutes.

Abstract: A method for delignifying ligno-cellulosic materials and efficiently separate from each other the constituents thereof. Said materials are heated in an aqueous acid medium in the presence of phenol compounds. Then the reaction medium is drained and washed for isolating the purified solid cellulose pulp, the liquid phase separating into two layers: an aqueous layer rich with pentoses and an organic layer rich with phenols and lignin, the latter providing, by distillation and pyrolysis of the residue, a quantity of phenols at least equal to that of the phenols used in the delignification stage.

Abstract: This invention relates generally to the extraction process and provides a novel process and reactor for the continuous extraction of vegetable-fibre material such as wood chips. The process comprises a two stage process, the first stage comprising an extraction process using a methanol:water mixture and the second stage using the same extraction liquid as the first with a greater proportion of water, with sodium hydroxide and anthraquinone. A part of the extraction liquid which is saturated by extraction substances is continually carried away at each stage and after extraction, the mixture is subjected to washing. This process has eliminated the heavy pollution produced by the prior art processes and also has reduced the cost and complexity of the prior art processes.

Abstract: Comminuted cellulosic materials which may or may not contain lignin are partially or totally hydrolyzed or saccharified by an improved organosolv process using an aqueous acetone solvent mixture containing a small amount of an acidic compound and containing at least about 70 percent by volume of acetone and up to virtually anhydrous acetone. The process is performed at elevated reaction temperatures, preferably at 145.degree. C. to 230.degree. C., for a limited period of time and then with cooling such that the resultant dissolved sugars from the hydrolysis are not degraded into non-sugars. In particular the reaction is conducted such that the cellulosic material is dissolved and such that at least ninety percent or more of available sugars in the cellulosic material are recovered. Unexpectedly it has been found that acetone at high concentration forms stable complexes with the sugars which prevents their degradation and also facilitates separation of the sugars.

Abstract: Process for cooking lignocellulosic materials by heating the said materials in a cooking solution containing caustic soda with or without an alkali metal sulphide, in which the solution used contains about 0.01% to 10%, preferably 0.05% to 2%, by weight of 1,2,3,4-tetrahydro-9,10-anthracenediol based on the weight of the dry lignocellulosic material.

Abstract: A process for producing corrugating medium pulp, fuel, and other products from a wide variety of woody materials is disclosed. In one embodiment a pulping solution is produced by cooking green chips in a water solution of monoethanolamine and subsequently collecting the liquor produced. Pulp is then produced by digesting chips under a vapor dome of the pulping solution, or cooking the chips in the solution and subsequently digesting under a vapor dome. Digested chips are then refined in pulping solution to produce corrugated medium pulp. In another embodiment, fuel may be produced by digesting woody material under a vapor dome with sulfur dioxide and ammonia. The digested chips then yield a lignin containing liquor which has a good fuel value and may be used as a liquid fuel or impregnate for woody material. In another embodiment the pulping solution is used as a hard wood conversion resin. Wood is impregnated and pressed. The pressed wood may have a density of twice the original wood.

Abstract: A process is provided for the alkaline oxygen delignification and bleaching of chemical cellulose pulp while inhibiting degradation of carbohydrates in the pulp, due to the presence of one or more aromatic diamines, preferably having the diamine groups directly linked to an aromatic ring.

Abstract: A method is provided for selectively defiberizing and delignifying lignocellulose employing a novel alkaline pulping system. The subject pulping system includes a pulping liquor comprising water, a water-miscible organic reagent, and a sulfide or bisulfide compound selected from the group consisting of alkali metal sulfides and bisulfides, ammonium sulfide and ammonium bisulfide. Extremely high pulp yields as compared to kraft pulping are provided by employing the method and system of this invention.

Abstract: A method and apparatus for reducing or eliminating the transfer of chemicals across a washer when reusing washer filtrate as a washing medium in a counterflow system. The flow of washing fluid on the washers before and after a treatment stage is split and the liquid in the pulp mat leaving the washer is principally the type used to treat the pulp after the washer, and the filtrate from the washer is principally the type used to treat the pulp before the washer.

Abstract: A process is provided for the processing of certain organic agricultural foodstuff by-products normally having little commercial value to produce a cellulosic product suitable for human consumption or use in various products. The process of the present invention is characterized by subjecting a variety of certain agricultural by-products having little commercial value, such as, for example, soy bean hulls, to a series of separate steps utilizing certain chemical treating to effect a solubilizing and removal of the non-cellulosic components of the by-product agricultural material to produce residue solids which consist essentially of cellulose. The cellulose residue solids are subjected to specified purification procedures and thereafter dried to produce a short, fine fibered cellulose which may be processed to a fine powdered state suitable for use as a component part in a wide variety of edible or otherwise useable products by humans, an example of such a product being a low calorie bread.

Abstract: Improved pulp strength and brightness of chemically produced pulp can be obtained by treating the pulp with the addition of 0.05-0.5% based on the weight of the dry fiber of certain amine materials in the hypochlorite bleaching stage.

Abstract: Improved pulp strength and brightness of chemically produced pulp can be obtained by treating the pulp with the addition of 0.05-0.5% based on the weight of the dry fiber of certain aromatic materials in the hypochlorite bleaching stage.

Abstract: A versatile process and apparatus is presented for producing, in high yields, many different grades of pulp from a single wood specie or for pulping any specie or type of woody material, and for storage and recycling of the by-product liquid and gaseous materials. The process of this invention is virtually pollution free, and the reactant chemicals are recoverable from the by-products. In the alternative, the by-products themselves have a commercial value which may forestall recovery of the reactants. The lignin constituent extracted from the pulp is usable as a resin binder, a wood rehardening agent, or a glue.

Abstract: In bleaching wood pulp with ozone a small amount of alcohol enhances the bleaching. The effect appears to be most pronounced with aliphatic alcohols having the hydroxyl group on an end carbon. The concentration of alcohol is in the range of 0.0000001 to 0.03 moles per liter of the liquid phase.

Abstract: A process for the preparation of viscose by adding to cellulose pulp, manufactured by alkali cooking without prehydrolysis or by acid cooking without alkali extraction, steeping lye and an organic compound, steeping the pulp to form alkali cellulose, aging the alkali cellulose, xanthating the aged alkali cellulose with carbon disulfide to obtain cellulose xanthate and dissolving the cellulose xanthate to obtain viscose.

Abstract: Pitch formation in paper mill pulp systems may be inhibited by treating such systems, at a point prior to where pitch deposits normally occur, with at least 0.

Abstract: Wood chips are digested at a temperature above 100.degree. C in contact with a solution of a hydroxide or salt of an alkali metal or alkaline earth metal or ammonium in a solvent which boils above 100.degree. C at atmospheric pressure, such as ethylene glycol. The cellulose pulp is then separated from the dissolved lignin. The dissolved lignin may be precipitated and removed from the solvent and the solvent may then be recycled, so that there is no waste spent liquor. Examples of salts which may be used are sodium phenoxide and a combination of sodium bisulfite and an aldehyde or a ketone.

Abstract: Solvent pulping of wood chips or other fibrous plant material is effected using an aqueous solution of a lower aliphatic alcohol in a plurality of batch extraction vessels. The charge in each vessel is heated rapidly to pulping temperature by recirculation of a primary extraction liquor having a relatively high dissolved solids content, and thereafter the charge is subjected to a series of once-through extractions or washes with successively cleaner liquors, including a final extraction or wash with fresh liquor. The extraction liquor from one extraction stage in one vessel is used in another extraction stage in another vessel. Upon completion of the extraction, the liquor is drained from the vessel, the vessel is depressurized to a solvent condenser, and the remaining solvent is steam stripped from the charge and recovered. The used extraction liquor is treated in an alcohol recovery system by flash vaporization, condensation of the solvent vapors, and vacuum stripping of the residual liquor with steam.

Abstract: Delignification of lignocellulosic material, such as wood, straw or bagasse, with a soda pulping liquor containing a diketo hydroanthracene selected from the unsubstituted and lower alkyl-substituted Diels Alder adducts of naphthoquinone and benzoquinone and a nitro aromatic compound selected from mono and di-nitrobenzenes and the amino, carboxy, hydroxy and methyl derivatives of said nitrobenzenes.

Abstract: When bleaching wood pulp with oxygen the result can be improved if formaldehyde, methanol, ethanol, isopropanol, glycerol, sorbitol, formic acid, or acetone is added to the pulp.

Abstract: In a process for the production of fiber substances from waste which contains aerobically unstable components, the waste is subjected to aerobic decomposition at a temperature of at least 50.degree.C in the presence of oxygen to form a fibrous mass and then the mass is treated with solvents which dissolve these components. This eliminates the odor characteristic of fiber substances produced from waste. An arrangement for carrying out the process is also disclosed.

Abstract: Prior to cooking, fragments of raw ligno-cellulosic material are impregnated with a solution of a lignin-solubilizing reactant in an organic solvent which has a boiling point higher than the cooking temperature in order for the material to absorb an amount of solution containing at least the amount of reactant required for solubilizing the lignin, then the impregnated material is immersed in a liquid which is substantially non-miscible with the solvent of said solution, said liquid having a boiling point higher than the cooking temperature, and said liquid is maintained at the cooking temperature until the lignin has been substantially converted to a derivative which is soluble in water or a water-miscible organic solvent.