Abstract: Production of ketene dimers from fatty acid halides by reaction with tertiary amines whereby the tertiary amine is used both as a reactant and as a solvent/diluent. In the process at least 1.15 moles of tertiary amine is used per mole of fatty acid halide and the process is carried out in the substantial absence of an additional solvent, whereby the produced ketene dimer is obtained by stripping of the tertiary amine followed by separation of formed crystals of tertiary amine hydrogen halide by acid extraction.

Abstract: A particulate alkaline detergent contains an alkaline agent and an alkali perborate hydrate and/or an alkali carbonate peroxohydrate as bleaching agent. As a result of coating at least the alkaline agent or the bleaching agent with an alkyl glycoside or an alkyl glycamide, the detergent has a low tendency to caking as well as excellent cleaning capacity. The alkyl glycoside is a C.sub.6 -C.sub.10 -alkyl glycoside having a degree of polymerization of 1-4, and the alkyl glycamide has formula (I), wherein R.sub.1 is hydrogen or an alkyl group having 1-4 carbon atoms, and R.sub.2 is an alkyl group having 6-10 carbon atoms. A bleaching agent and an alkaline agent coated with the alkyl glycoside and/or the alkyl glycamide are also disclosed.

Abstract: A plug flow process for the production of chlorine dioxide by reacting chloric acid and/or an alkali metal chlorate, optionally a mineral acid and a reducing agent in such proportions that chlorine dioxide is produced. Reactants are continuously fed to a plug flow reactor under conditions that chloride dioxide is produced as the reactants flow through the reactor. The process stream has an acidity between 2N and 11N. The process stream is subjected to superatmospheric pressure in the reactor sufficient to maintain the formed chlorine dioxide in solution. After removal of the chlorine dioxide from the process stream exiting the plug flow reactor, the process stream can optionally be fed to a second chlorine dioxide generator for further reaction.

Abstract: The present invention relates to a sized paper containing a hydrophobic zeolite. Suitably, the sized paper is fine paper, kraft liner or paperboard. In paperboard intended for solid or liquid foodstuffs, tobacco or medicines, use is also made of the capacity of the zeolite to reduce, by adsorption, the problem of transfer from the package to its content of substances causing undesirable taste or hazardous substances. The present invention also relates to a method for production of the sized paper by forming and dewatering a suspension of lignocellulose-containing fibres, where the dewatering is carried out in the presence of a hydrophobic zeolite. Due to the inert nature of the zeolite, it can be used in papermaking within a very broad pH range. The present invention also relates to the use of a hydrophobic zeolite for the production of sized paper as well as use of the thus-sized paper in packaging material.

Abstract: Silica sols having a high content of microgel and aluminum modified particles with high specific surface area. The sols can be prepared by a process comprising acidification of a water glass solution, alkalization at a certain dry substance content, particle growth and aluminum modification. The sols are particularly suitable for use as additives, in combination with cationic polymers, in papermaking.

Abstract: The invention relates to a method for preventing fish-borne parasites from spreading to a watercourse (1) or a limited area (4) of a watercourse (1) without such parasites. According to the invention, all the fish to pass into the area (4) are forced to go through a bath of water containing an active substance which kills or removes from the fish the parasite or parasites which should be prevented from spreading, without killing or seriously injuring the fish. The invention also relates to a plant for carrying out the method.

Abstract: The invention relates to a method for removing calcium ions and silicon compounds from various liquors produced or obtained in an alkali metal chlorate process, thereby reducing the operating cost and improving the possibility to close the process further. The calcium ions and silicon compounds are removed by addition of carbonate ions for precipitating calcium carbonate and by addition of an iron-containing compound for forming and precipitating a complex of iron ions and a silicon compound, whereupon the precipitates are co-separated from the liquor. The removal of calcium and silicate ions is substantially facilitated by the simultaneous separation of the precipitates. Subsequently, the excess of carbonate ions can be reduced by acidifying the electrolyte for releasing carbon dioxide.

Abstract: Wood-resin-containing process water or wastewater from the pulp industry is purified by adding, as flocculants, a high-molecular-weight polyethylene oxide and a water-soluble, non-ionic cellulose ether, suitably having a flocculation temperature of 35.degree.-80.degree. C. The added amount per liter of water is preferably 2-20 mg of the high-molecular-weight polyethylene oxide and preferably 5-30 mg of the non-ionic cellulose ether.

Abstract: The invention relates to a method for separating sulphate from an aqueous electrolyte in an alkali metal chlorate process, thereby reducing the operating cost and increasing the possibility of further closing the electrolytical production of alkali metal chlorate. Calcium ions are added to a portion of the electrolyte, for precipitating calcium sulphate. By adjusting the pH within the range of from 4.6 up to about 7, and combining the temperature, content of ions and the molar ratio between sulphate and calcium ions added in a suitable manner, the calcium sulphate will precipitate predominantly as gypsum and essentially without inclusions and/or co-precipitation of chromium-containing compounds or chlorate. The precipitate is subsequently removed from the portion of electrolyte, whereafter the thus purified portion of electrolyte is recycled to the chlorate process.

Abstract: The invention concerns a solid alkalimetal silicate having a molar ratio SiO.sub.2 :M.sub.2 O from about 1.5 to about 3, in which M is an alkalimetal substantially consisting of sodium and potassium. The silicate contains from about 1 and up to about 5% by weight of K.sub.2 O based on the dry material and the water content being from about 16 to about 25% by weight based on the total weight.Further, the invention concerns a method of its preparation, its use and a cleaning agent composition containing the silicate above.

Abstract: The invention concerns a solid alkalimetal silicate having a molar ratio SiO.sub.2 :M.sub.2 O from about 1.5 to about 3, in which M is an alkalimetal and substantially consists of sodium and optionally potassium. The silicate contains from about 7 to about 20% by weight of sodium carbonate based on the dry material and has a water content from about 14 to about 22% by weight.Further, the invention concerns a method of preparing the silicate above, use of the same and cleaning agent compositions containing such a silicate.

Abstract: The present invention relates to particles having a core comprising a peroxy compound and a hydrophobic coating comprising:(a) a hydrophobic substance selected from saturated fats, waxes or phosphatides;(b) a surfactant dissolved in the hydrophobic substance;(c) water swellable grains;the hydrophobic substance and the surfactant being substantially inert in respect of the peroxy compound.The invention also relates to preparation and use of the particles. Further, the invention relates to a composition containing such coated particles.

Abstract: An agent for controlling parasites on fish consists of an aqueous solution containing more than 1.2 but less than 2.9 g H.sub.2 O.sub.2 per liter. Disclosed are also a method for preparing such an agent and a method for controlling parasites in fish breeding.

Abstract: The invention relates to a process for bleaching chemically delignified lignocellulose-containing pulp, to render more efficient a peroxide-containing treatment stage, by treating the pulp with a complexing agent before the peroxide step, so that the trace metal profile of the pulp is altered by the treatment with the complexing agent, in the absence of sulphite, at a pH in the range from 3.1 up to 9.0 and at a temperature in the range from 10.degree. C. up to 100.degree. C., whereupon, in a subsequent step, the treatment with a peroxide-containing substance is carried out at a pH in the range from 7 up to 13, said two-step treatment being carried out at an optional position in the bleaching sequence applied to the pulp.

Abstract: The present invention relates to a process to limit the content of impurities in the production of alkali metal chlorate, by integrating the production of chlorate with the production of chlorine and alkali metal hydroxide, which auxiliary chemicals are used in the chlorate process. The alkali metal chlorate is produced by electrolysis of a purified electrolyte containing alkali metal chloride, alkalization of the chlorate electrolyte obtained and precipitation of the chlorate formed by evaporation of the chlorate electrolyte. The very pure water separated in the crystallizer and alkali metal chloride is used in a membrane or diaphragm cell in the production of alkali metal hydroxide, which hydroxide is used in the production of alkali metal chlorate. Either pure chlorine or hydrogen chloride absorbed in water can be used in acidification, at which hydrogen chloride is produced from chlorine and hydrogen generated in the process.

Abstract: In a method for preparing a starch solution, particles containing starch are mixed with cold water and subjected to shear forces, such that any agglomerates formed are broken up, and each individual particle is wetted, whereupon the mixture is heated to at least about 60.degree. C. and maintained in the heated state until the viscosity maximum of the solution has passed. The wetting and the heating take place before a viscosity that is unacceptable from the point of view of handling has been reached.A device for implementing the method, a starch solution prepared in accordance with the method, and the use of such a starch solution for making paper are also disclosed.

Abstract: Cellulose fibre containing products in sheet or web form, such as paper and pulp sheets, are produced from a suspension of cellulose containing fibres, and optional fillers, to which is added anionic inorganic particles, such as bentonite and silica based particles, and a cationic carbohydrate polymer containing aluminum. The cationic carbohydrate polymers are cationic galactomannans or cationic starch. High cationized starch with a degree of substitution of at least 0.07 are especially suitable.

Abstract: Silica particles which are substantially spherical, have a particle size of 1 to 100 .mu.m, a very narrow pore size distribution and a low alkali metal content. The particles can be prepared by sol-gel technique using emulsification technique for drop formation. The process comprises a sol growth step in a basic environment based on ammonium or amines and a post-treatment in such an environment. The silica particles are particularly suitable for use in chromatography as they have very good particle and porosity properties and high purity.

Abstract: A process for the production of chlorine dioxide by reacting an alkali metal chlorate, mineral acid and a reducing agent in such proportions that chlorine dioxide is produced in a reaction medium which is maintained at a temperature of 50.degree. C.-100.degree. C. and at an acidity within a range of 2-12 N and which is subjected to subatmospheric pressure sufficient for evaporating water. A mixture of chlorine dioxide and water vapour is withdrawn from an evaporation zone in the reaction vessel, and alkali metal sulphate is precipitated in a crystallization zone in the reaction vessel. The precipitated alkali metal sulphate is contacted with a saturated water solution of alkali metal sulphate whereafter neutral alkali metal sulphate is precipitated and dissolved in water. The water solution is brought to an electrochemical membrane cell in which sulphuric acid is formed in the anode compartment and alkali metal hydroxide in the cathode compartment.

Abstract: The invention concerns a method of bleaching particles containing calcium carbonate by keeping them in contact with an aqueous solution containing hydrogen peroxide and having a pH-value below 8.