It is an object of the present invention to provide a thickener capable of exhibiting excellent light resistance. The present invention relates to a thickener comprising cellulose fibers having a fiber width of 8 nm or less and water, wherein the thickener is a slurry or a gel, and when the thickener is filled in a colorless and transparent glass cell having an inside dimension of 1 cm in depth4 cm in width4.5 cm in height and the thickener is then irradiated with ultraviolet rays with a wavelength of 300 nm or more and 400 nm or less, using a xenon lamp, from the side of the maximum area surface of the glass cell, so as to be an irradiance of 180 W/m.sup.2 and an integrated light amount of 500 mJ/m.sup.2, the amount of a change in the yellowness before and after ultraviolet irradiation measured in accordance with JIS K 7373 is 10 or less.

The present invention relates to the preparation of a cellulose suspension, particularly of a premixture for the preparation of a cellulose suspension in organic solvents such as an aqueous N-methylmorpholine N-oxide (NMMO) solution.

According to an example aspect of the present invention, there is provided a method of separating cellulose and polyester from a material comprising a blend of cellulose and polyester, said method comprising the steps of mixing the material comprising a blend of cellulose and polyester with a first portion of superbase-based ionic liquid to dissolve a first portion of cellulose and form a first cellulose solution and a first residue comprising polyester, removing the first residue comprising polyester from the first cellulose solution, and directing the first cellulose solution to one or more further processing steps.

A heat exchanger pipe system is provided for transporting viscous fluids, including a plurality of individual heat exchangers designed as pipe elements and having a predefined control temperature and/or pressure distribution along the pipe system and in the cross-section of the pipes. The heat exchangers, which are in the form of pipe elements, are arranged at regular distances in the pipe system. The regular distances are selected in such a manner that a predetermined temperature and/or pressure distribution is maintained along the pipe system, tempering apparatus of a viscous fluid transported in the heat exchanger pipe are arranged in the heat exchangers and optional mixing elements which are used to maintain, in accordance with the pipe cross-section, a predetermined temperature and pressure distribution in the cross section of the pipes, and at least 30% of the length of the heat exchanger pipe system is equipped with heat exchangers.

The invention relates to a process for treating a lignocellulosic material, preferably wood, comprising the following steps: (1) soaking of the material with organic fluid in order to dissolve at least 40% and at most 85%, in weight %, of the lignin of the material; (2) washing with organic fluid so as to discharge the dissolved lignin; (3) filling with a filling compound; and (4) finishing, so as to obtain a composite formed of a three-dimensional network of transformed filling compound incorporated into a cellulose and lignin network. The invention also relates to a composite structure able to be obtained in this way, and to any part comprising at least one such structure.

A wood-derived carbohydrate composition is disclosed. The wood-derived carbohydrate composition comprises monomeric C6 sugars and monomeric C5 in a total amount of at least 94 weight-% based on the total dry matter content of the carbohydrate composition, wherein the weight ratio of the monomeric C5 sugars to the monomeric C6 sugars is at most 0.1. Disclosed is also a method for producing a wood-derived carbohydrate composition.

The invention relates to a thin film evaporator (D) for producing a transfer mixture according to the direct dissolution method, having a feed (1), a housing (4) and an outlet (2), wherein the feed (1) introduces a starting material, made of cellulose, water and a functional fluid, into the housing (4), wherein an evaporator shaft (5) situated in the housing (4) rotatingly sweeps the starting material over the heated interior of the housing (4), wherein the product is heated and some of the water evaporates so as to result in the transfer mixture, which flows to the outlet (2) together with a supply stream, wherein the through-flow capacity of the outlet (2) is greater than the supply stream.

The present invention provides a powder-assembled composite micro-nano fiber and a method for preparing the powder-assembled composite micro-nano fiber. The method includes the following steps: (1) preparing two-dimensional cellulose from a cellulose-raw-material; (2) dispersing the two-dimensional cellulose and a powder material in a solvent to form a mixed suspension; and (3) performing freeze drying on the mixed suspension to obtain the powder-assembled composite micro-nano fiber, wherein a temperature difference between two ends in a vertical direction of the mixed suspension is controlled to be 10-100? C. in a freezing process of the freeze drying. In the present invention, a new non-destructive processing path from primary particles to macro applications is constructed, and rich material platforms and infinite possibilities are provided for basic studies and technical applications. The technology will play a huge role in energy, medical material, environment, protection, catalysis, photoelectricity, food engineering, daily necessity and other vast fields.

The invention proposes a polymer solution for visco-supplementation. The polymer solution contains at least one at least partially water-soluble polysaccharide or polysaccharide derivative, one water-soluble alkali salt or alkaline earth salt of polystyrene sulfonic acid, and water, whereby the polymer solution is clear to the eye. Moreover, the invention describes a method for sterilization of the polymer solution. This method is characterized in that a mixture of at least one at least partially water-soluble polysaccharide or polysaccharide derivative, one water-soluble alkali salt or alkaline earth salt of polystyrene sulfonic acid, and water is mixed with at least 0.5 wt. % -propiolactone, and in that the polymer solution is stored at room temperature for at least 24 hours.

The invention relates to a method for regenerating cellulose fibers from cotton-containing textile, wherein the degree of polymerization (DP) of cellulose in cotton is reduced by using a DP decreasing agent, which is an endo-cellulase of the type EC Number 3.2.1.4, together with mechanical energy. The DP of cellulose in cotton is reduced to under 1500, which makes it particularly suitable for the following steps, especially the spinning step. The cellulose is further dissolved using cellulose solvent comprising NMMO or an aqueous mixture of NMMO and the obtained cellulose-containing liquid is subjected to a spinning process to produce cellulose fibers.