A modified aqueous acid composition comprising: sulfuric acid; a compound comprising an amine moiety and a sulfonic acid moiety; and a peroxide; wherein sulfuric acid, said compound comprising an amine moiety and a sulfonic acid moiety and said peroxide are present in a molar ratio of no less than 1:1:1. Also disclosed are methods of using such compositions.

In a process for producing bleached mechanical woodpulp, said process comprising the steps of a) delaminating comparatively large particles of wood, which have optionally been pretreated with chemicals and/or water, into modified particles of wood, b) grinding the modified particles of wood from a) in one or more refiners, c) optionally treating the stalk obtained in step b) with oxidative or reductive bleaching agents, a composition Z is present during step a) and/or step b), said composition Z comprising one or more of the following components (Z1) to (Z3): a salt of dithionous acid H.sub.2S.sub.2O.sub.4 (Z1), a dithionous acid or dithionous acid derivative generator compound (Z2), a salt of sulfurous acid (sulfite) plus sodium tetraborohydride (Z3) and also optionally additives (Z4).

The present invention provides methods for obtaining Baobab fibers derived from Baobab trees. The methods include obtaining Baobab plant material, dewatering of the Baobab plant material, and subsequent separation of the dewatered Baobab plant material. The present invention allows a resource-saving separation of the fibers, for example, through a dewatering of the Baobab plant material. Baobab fibers obtained according to the methods of the present invention can be used for a variety of purposes, for instance, for producing chemical pulp, paper, paperboard, carton, special papers, fabrics and fiber-reinforced plastics.

A defibrating method includes the steps of: preparing a material which contains fibers and a compound represented by the following formula (1); and defibrating the material.

RO(EO).sub.m(PO).sub.nH   (1)

In the formula, R represents an alkyl or an alkenyl group having 6 to 22 carbon atoms or an alkylaryl group including an alkyl group which has 4 to 20 carbon atoms, E represents an ethylene group, P represents a propylene group, m and n each represent an average number of added moles, m represents a numerical value of 0 to 20, n represents a numerical value of 1 to 10, and (EO).sub.m(PO).sub.n represents a block addition structure.

A modified aqueous acid composition comprising: sulfuric acid; a compound comprising an amine moiety and a sulfonic acid moiety; and a peroxide; wherein sulfuric acid, said compound comprising an amine moiety and a sulfonic acid moiety and said peroxide are present in a molar ratio of no less than 1:1:1. Also disclosed are methods of using such compositions.

A method is provided for recovering pulp fibers having little damage from a used absorbent article that contains pulp fibers and a superabsorbent polymer. The used absorbent article is treated at a temperature of greater than or equal to 80 C. with an organic acid aqueous solution having a pH no greater than 2.5, and the superabsorbent polymer is deactivated. Preferably, the pulp fibers and the deactivated superabsorbent polymer are separated from the used absorbent article after treatment with the organic acid aqueous solution, and further, a mixture including the separated pulp fibers and deactivated superabsorbent polymer is treated with an oxidizing agent, the deactivated superabsorbent polymer is decomposed, reduced in molecular weight and solubilized.

A modified aqueous acid composition comprising: sulfuric acid; a compound comprising an amine moiety and a sulfonic acid moiety; and a peroxide; wherein sulfuric acid, said compound comprising an amine moiety and a sulfonic acid moiety and said peroxide are present in a molar ratio of no less than 1:1:1. Also disclosed are methods of using such compositions.

The present invention relates to a method of preparing grafted copolymers of lignin and/or cellulose, comprising the generation of macroradicals in situ by mechanical impact on the backbone of said lignin and/or cellulose of said lignin and/or cellulose containing material and grafting monomers and/or polymers to said backbone. Furthermore, the present invention relates to the grafted copolymers obtainable by said method, composite materials comprising said copolymers as well as to uses thereof.

Disclosed herein is a process, comprising: combining one or more additives with a feedstock to obtain a first mixture, the feedstock comprising a fibrous material and water, the fibrous material comprising lignin, cellulose, and hemicellulose; and conditioning the first mixture to obtain a liquid product and a dry pulp product. Also disclosed herein are condition processes and machines for use with the same. Also disclosed herein are liquid products, dry pulp products, and fibrous pellets made by the disclosed processes, and methods of using the same.

Provided is a method that, when pulp fibers are recovered from used absorbent articles that have been put into collection bags, makes it possible to safely and sanitarily crush the used absorbent articles while suppressing costs. A method for recovering pulp fibers from used absorbent articles, the method comprising: a crushing step (S12) in which collection bags (A) in which used absorbent articles have been sealed are put into a container (65), the collection bags in the container are transferred to a crushing device (12) that communicates with the container, and, bag by bag, the crushing device crushes the used absorbent articles in the collections bags in a deactivating aqueous solution; and a separation step (S13) in which the pulp fibers, a highly water-absorbent polymer, and the deactivating aqueous solution are separated from the crushed product and deactivating aqueous solution obtained in the crushing step.