摘要:
A process for manufacturing fiber boards and similar wood-based products from a lignocellulosic raw material having a moisture content of at least 10 wt-%. According to the process, an aqueous fraction is separated from the fibers of the raw material, which fraction later is recycled to the process in order to form at least a part of the agent used for binding the fibers. Before mixing with the fibers, the aqueous effluent is concentrated and enzymatically oxidized in the presence of oxygen in order to polymerize the solubilized wood material and in order to increase its concentration. Lignin can be added to the water solubilized wood material or the solubilized wood material can be added to the fibers together with another binder. Eventually, the mixture is formed into a board and hardened.
摘要:
The invention relates to an intermediate product for the preparation of polymerizates from lignin derivatives obtained from the cellulose industry. The intermediate product is produced by treating the lignin derivatives with enzymes capable of oxidizing phenol in the presence of oxidizing agents. According to the invention the lignin derivatives are subjected to the enzymatic treatment for more than 3 hours in the presence of air, or they are subjected to an enzymatic treatment for more than 10 min, whereby air or oxygen is introduced. The lignin polymers obtained from the polymerization of lignin derivatives performed in the presence of active intermediate products are suited for use in the production of binding agents for wood materials.
摘要:
An adhesive binder for bonding together lignocellulosic particles, fibers and flakes of vegetable origin to form particle boards, fiber boards, flake boards and similar wood-based products, comprising a solublized fraction obtained by enzymatic treatment of fibrous, lignocellulosic raw materials. The present binder can be obtained by treating fibrous lignocellulosic raw material with a hydrolytic enzyme in an aqueous medium, recovering the solubilized material of the enzymatic treatment, forming an aqueous suspension containing said material and an oxidase, and oxidizing said material in the presence of said oxidase by introducing oxygen-containing gas into the supension. This method thus produces an increased amount of a water-soluble fraction containing carbohydrates, extractives and lignin useful as an adhesive binder.
摘要:
A thin film structure, method of producing it and the use thereof. The thin film structure comprises a substrate with a thin conductive layer containing an oxidizing enzyme mixed with an electron transfer mediator. The thin layer is protected against wetting to allow for its storage in dry conditions and further being sufficiently porous to allow for immediate activation of the oxidizing enzyme when contacted with an aqueous solution. The thin film can be used as a cathode in electrochemical fuel cells.
摘要:
A thin film structure, method of producing it and the use thereof. The thin film structure comprises a substrate with a thin conductive layer containing an oxidizing enzyme mixed with an electron transfer mediator. The thin layer is protected against wetting to allow for its storage in dry conditions and further being sufficiently porous to allow for immediate activation of the oxidizing enzyme when contacted with an aqueous solution. The thin film can be used as a cathode in electrochemical fuel cells.
摘要:
The present invention relates to the production of sugar hydrolysates from cellulosic material. The method may be used e.g. for producing fermentable sugars for the production of bioethanol from lignocellulosic material. Cellulolytic enzymes and their production by recombinant technology is described, as well as uses of the enzymes and enzyme preparations.
摘要:
The present invention concerns a process for reducing the susceptibility of lignocellulosic material to unwanted yellowing, particularly yellowing caused by light and heat. According to the invention, the fibres are activated enzymatically or chemically and then contacted with a modifying agent capable of bonding to the oxidized fibre material, rendering the lignocellulosic fibre material improved resistance to brightness reversion. By means of the invention, brightness reversion caused by light or heat or a combination thereof can be retarded and even stopped.
摘要:
The present invention concerns a process for producing fibre composites. In particular, the invention provides a novel way of producing biodegradable composites comprising a hydrophobic polymer material and a reinforcing component of fibres derived from plant materials. Composite material produced by means of the present invention has improved strength properties and enhanced adhesion between the bifunctional fibre and the natural or synthetic polymer.
摘要:
The present invention relates to novel cellulase enzymes, especially novel endoglucanases including endoglucanase fusion proteins, preparations and compositions containing these endoglucanase enzymes and fusion proteins, expression vectors, host cells and methods for their preparation and uses of the cellulases, preparations and compositions in the textile, detergent and pulp and paper industries.
摘要:
The invention relates to a process for enhancing the concentration of the fiber derived dissolved and colloidal substances in process water that comes from mechanical pulping. According to the invention, process water is treated with enzyme preparations that have an effect on carbohydrates and that contain mannanase and/or endoglucanase, in particular, which break down the soluble carbohydrate polymers contained by the process water into low molecular weight oligosaccharides. The treatment prevents an increase in viscosity so that process water can be concentrated into a high dry content, or the treatment can be used to lower the viscosity of previously concentrated process water to facilitate after-treatment.