Abstract:
The present invention relates to a method for recovering lanthanoid catalyst from the preparation of aspartic acid diethoxy succinate comprising contacting a carbonate source with a solution containing lanthanoid ions derived from said preparation and a chelating agent different from aspartic acid diethoxy succinate to precipitate lanthanoid carbonate followed by separating the precipitated lanthanoid carbonate from the solution.
Abstract:
The present invention relates to a method and an arrangement for recovery of at least one organic acid from a dilute aqueous solution thereof. In this method a complex between said organic acid and an extractant is formed by contacting the solution with a reactive extractant and dissolving the formed complex into said extractant thus forming an extractant phase. The organic acid is removed from the formed complex by esterification using an alcohol.
Abstract:
The invention relates to a method for preparing an organic starch ester. The method comprises mixing a starch material with an ionic liquid solvent to dissolve the starch, and then treating the dissolved starch with an organic esterifying agent to form an organic starch ester, and subsequently separating the organic starch ester from the solution. Microwave irradiation and/or pressure can be applied to assist in dissolution and esterification.
Abstract:
Methods for the preparation of an N-alkyl-N-bis-(2-( 1,2-dicarboxy-ethoxy)-ethyl)-amine derivative are described, products of the methods as well as uses of the products. The derivative is prepared by reacting an alkali or earth alkali metal salt of maleic acid with an N-substituted diethanolamine, the reaction taking place with the two ethanol groups of the diamine while the substituent group bound to the N atom remains unaffected, or alternatively by first reacting diethanolamine with an alkali or earth alkali metal salt of maleic acid to yield N-bis-(2-(1,2-dicarboxy-ethoxy)-ethyl)-amine, which is then reacted with a substitution reagent to obtain the final product. The derivative is useful as chelating agents, e.g., in the bleaching of chemical or mechanical pulp or in textile bleaches containing hydrogen peroxide or a peracid, or as a calcium binder in detergents and cleaning agents.
Abstract:
The present invention relates to a process for the preparation of a solution comprising a first peroxy acid comprising performic acid and a second peroxy acid, said process comprising forming a carboxylic acid solution comprising a first carboxylic acid comprising formic acid, a second carboxylic acid and hydrogen peroxide, wherein the amount of formic acid is from 0.5 to 20% by weight of the amount of the second carboxylic acid, and allowing the components to react to form a solution comprising performic acid and said second peroxy acid, the amount of peroxy acids being at least 5% by weight. The invention also relates to a storable solution comprising performic acid and said second peroxy acid. The solution can be used as a disinfecting agent for controlling micro-organisms.
Abstract:
A method for treating lignin-containing fibrous material to reduce its susceptibility to yellowing generally includes enzymatically stabilizing the lignin of the material with an oxidizing agent capable of oxidizing phenolic or similar groups, which may undergo reactions conductive to the formation of colored sites on the fibers, and treating the material with a fluorescent whitening agent. Also disclosed are lignin-containing materials obtained by the method.
Abstract:
The invention relates to a method for preparing a cellulose ether. The method comprises mixing cellulose with an ionic liquid solvent to dissolve the cellulose, and then treating the dissolved cellulose with an etherifying agent in the presence of an inorganic base to form a cellulose ether, and subsequently separating the cellulose ether from the solution, wherein both the dissolution and the etherification are carried out in the absence of an organic base and in the substantial absence of water. Microwave irradiation and/or pressure can be applied to assist in dissolution and etherification.
Abstract:
A method of hydrogenating alkyl anthraquinones and/or alkyl hydroanthraquinones to alkyl anthrahydroquinones and/or alkyl hydroanthrahydroquinones is disclosed. The reaction is carried out in the presence of a catalyst under electromagnetic irradiation, such as microwave irradiation. The invention further relates to a method of hydrogenating a working solution in a hydrogen peroxide production process, wherein the working solution contains alkyl anthraquinones and/or alkyl hydroanthraquinones dissolved in at least one solvent to convert the quinines to the corresponding alkyl anthrahydroquinones and/or alkyl hydroanthrahydroquinones, where the reaction is carried out in the presence of a catalyst under electromagnetic irradiation such as microwave irradiation.
Abstract:
The invention relates to a process for the bleaching of chemical pulp, wherein the pulp is delignified and/or bleached with chlorine dioxide or with a combination of chlorine dioxide and a per-compound, and additionally the pulp is chelated in order to bind heavy metals, such as Fe, Mn and/or Cu, to a chelate complex. The chelate complex is selected from the group made up of N-bis-[(1,2-dicarboxylethoxy)-ethyl]-amine, N-bis[(1,2-dicarboxylethoxy)-ethyl]-aspartic acid and N-tris-[(1,2-dicarboxylethoxy)-ethyl]-amine, and the alkali metal and earth-alkali metal salts of these, and the chelating treatments are carried out simultaneously by combining the chelating chemical with the pulp in the same bleaching stage as chlorine dioxide.
Abstract:
The invention relates to a polymer product obtained by polymerization of i) at least one monomer selected from N-vinylformamide and vinyl acetate, and ii) maleic anhydride to give a copolymer comprising N-vinylformamide and/or vinyl acetate and maleic anhydride followed by hydrolyzing formamide groups originating from N-vinylformamide to amino groups and/or acetate groups originating from vinyl acetate to hydroxyl groups and acid anhydride to dicarboxylic acid groups to give a water-soluble copolymer comprising amine and/or hydroxyl and carboxyl groups, wherein the molar ratio of the N-vinylformamide and/or vinyl acetate monomer to the maleic anhydride monomer is from 70:30 to 30:70. The polymer product can be used as a dispersing agent or as a scale inhibiting agent.