Disclosed is a method of purification of utilized acetylation fluid recovered from a process of acetylating wood. The method involves subjecting the recovered acetylation fluid to cooling crystallization. By this method terpene and terpenoid impurities are removed, as well as other impurities. Disclosed is also a method of acetylating wood resulting in acetylated wood and utilized acetylation fluid comprising acetic acid, and purifying the utilized acetylation fluid by cooling crystallization.

The disclosure relates to a method for continuous acetylation of wood elements. The acetylation is conducted with an acetylation medium at a pressure of at least 1.5 barg in a substantially oxygen free environment. Alternatively, the method includes the steps of: (a) feeding wood elements in a substantially oxygen free environment to a continuous acetylation reactor, and (b) treating the wood elements with an acetylation medium in the continuous acetylation reactor under wood acetylation reaction conditions, at a pressure of at least 1.5 barg. The process can acetylate wood elements to a high acetyl content in an efficient way, without compromising on the quality of the material. The acetylated wood elements can be used in the production of medium density fibreboards with superior qualities such as dimensional stability and durability.

Disclosed is a board made from acetylated mbberwood elements and a method for making same. The acetylated rubberwood elements have an acetyl content of at least 17% and/or are prepared by acetylating mbberwood elements using an acetylation agent in the vapour phase. The invention also pertains to acetylated rubberwood elements prepared by using an acetylation agent in the vapour phase.

A process for the production of acetylated wood elements, a cooling system and a wood acetylation plant are described. A process for the production of acetylated wood elements comprises acetylating wood elements and cooling the acetylated wood elements wherein the cooling comprises supplying liquid water to the acetylated wood elements to provide wetted wood elements and exposing the wetted wood elements to a gas flow.

The present invention relates to a method for continuous acetylation of wood elements. The acetylation is conducted with an acetylation medium at a pressure of at least 1.5 barg in a substantially oxygen free environment. Alternatively, the method according to the invention comprises the steps of: (a) feeding wood elements in a substantially oxygen free environment to a continuous acetylation reactor, and (b) treating the wood elements with an acetylation medium in the continuous acetylation reactor under wood acetylation reaction conditions, at a pressure of at least 1.5 barg. The process according to the present invention allows to acetylate wood elements to a high acetyl content in a very efficient way, without compromising on the quality of the material. The acetylated wood elements can be used in the production of medium density fibreboards with superior qualities such as dimensional stability and durability.

This application relates to the technical field of building material processing, and more particularly, to a method for manufacturing a transparent heat-insulation building material based on waste wood. The method includes the following steps of: step S1, wood pretreatment, step S2, wood acetylation treatment, step S3, resin impregnating, and step S4, hot press molding to obtain a densified wood.

A wood treatment method for reducing fungal growth utilizes a treatment solution comprising an aldehyde, a carrier solvent, an organic co-solvent, at least one surfactant, and at least one acid, base, or salt. In embodiments, the carrier solvent may comprise water and the organic co-solvent may comprise an alcohol or acetone. The aldehyde is impregnated into the wood, where it reacts with thiamine and other amino acids to promote cross-linking, reducing the porosity of the wood and thereby reducing the ability of various microbes and fungi to access the interior of the wood as a nutrient source.

Disclosed is a process for the acetylation of wood. The wood to be acetylated is first subjected to an extraction step. The resulting extracted wood particularly has a reduced hemicellulose content. This extracted wood is subjected to contact with an acetylation agent. The extraction can be done with an extraction fluid which is, e.g., water, acetone, ethanol, methanol, or acetic acid. The water can be pure water, such as tap water or demineralised water, or it can be a dilute salt solutions (e.g. water containing ammonium oxalate or sodium sulphite). Hot water extraction is preferred. The resulting acetylated extracted wood, particularly wood elements, have a desirable swelling behaviour at lower acetyl contents than conventional acetylated wood. The wood can be in the form of wood elements, solid wood, or wood veneers.

A system for treating wood (30), comprising: a treatment vessel (14) configured to receive at least one wood stack (4) for treatment, and a stack holding system (2) for holding a wood stack (4), the stack holding system (2) comprising: a frame (6), configured to support the wood stack (4); a first element (8), connected to the frame (6) near an upper side of said frame (6), configured to exert a first, downward force on the wood stack (4); and a second element (10), connected to the frame (6) near a lower side of said frame (6), configured to exert a second force on the wood stack (4) in a direction opposite said first force. The invention also comprises a method for treating wood, using a system for treating wood according to the invention.

A method of treating wood includes subjecting the wood to a vacuum environment, and thereafter contacting the wood under positive pressure with an aldehyde and an isocyanate, both the aldehyde and the isocyanate being in liquid form.