摘要:
A method for manufacturing pulp. The manufactured pulp includes at least 30 w-% nanofibrillated cellulose material measured from the dried pulp. A raw material is introduced to a system. The raw material includes cellulose. At least one type of an optical brightening agent is dosed as a refining additive to the system. The raw material is refined in the presence of the dosed optical brightening agent in at least one pre-refining stage or fibrillation stage to form fibrillar cellulose material.
摘要:
The invention relates to a method for processing an aqueous gel of nanofibrillar cellulose by removing water from the aqueous gel by means of an organic solvent miscible with water. In the method: aqueous gel is introduced into a volume of organic solvent miscible with water in a controlled manner so that the aqueous gel is kept as a separate phase and forms discrete physical entities containing the nanofibrillar cellulose within the phase; water is changed with the organic solvent in said discrete physical entities of nanofibrillar cellulose; and the physical entities are separated from the volume of organic solvent.
摘要:
The invention relates to a method for processing an aqueous gel of nanofibrillar cellulose by removing water from the aqueous gel by means of an organic solvent miscible with water. In the method: aqueous gel is introduced into a volume of organic solvent miscible with water in a controlled manner so that the aqueous gel is kept as a separate phase and forms discrete physical entities containing the nanofibrillar cellulose within the phase; water is changed with the organic solvent in said discrete physical entities of nanofibrillar cellulose; and the physical entities are separated from the volume of organic solvent.
摘要:
In a method for catalytic oxidation of cellulose a heterocyclic nitroxyl radical is used as catalyst, hypochlorite is used as main oxidant acting as oxygen source, and a tertiary amine or chlorine dioxide as an activator of the heterocyclic nitroxyl radical.
摘要:
In a method for catalytic oxidation of cellulose a heterocyclic nitroxyl radical is used as catalyst, hypochlorite is used as main oxidant acting as oxygen source, and a tertiary amine or chlorine dioxide as an activator of the heterocyclic nitroxyl radical.
摘要:
A Method of pretreating native cellulose pulp in the manufacture of nanofibrillated cellulose, and a nanofibrillated cellulose product obtainable by the method.
摘要:
A method for manufacturing cellulosic material includes: introducing cellulose fibers as cellulosic raw material to a system, conveying the cellulose fibers to an extruder comprising a mixing part and/or a refining part, dosing at least one chemical to the system before the extruder and/or in the extruder and performing a reaction between the cellulose fibers and the chemical(s) at least partly in the extruder, wherein the reaction is performed at a consistency of at least 40%, and/or dosing at least one chemical to the system before the extruder and/or in the extruder and mixing the cellulose fibers and the chemical(s) in the mixing part of the extruder, wherein the mixing step is performed at a consistency of at least 40%, and/or refining the introduced cellulose fibers at least partly in the refining part of the extruder, wherein the refining step is performed at a consistency of at least 5%.
摘要:
Described herein is nanocellulose produced by introducing a mixture of cellulose based fiber raw material and water through a refining gap, having a width smaller than 0.1 mm. In the refining gap, the fiber raw material is subjected to processing forces varying in the direction of introducing said mixture, by means of refining zones provided in the gap one after each other in the feeding direction, whereby the refining surfaces differ in surface patterning and/or surface roughness. The mixture of fiber raw material and water is guided past the refining surfaces in the feeding direction to different locations in the refining zone by by-pass channels provided in the stator. The width of the refining gap is maintained by the combined effect of the feeding pressure of the mixture of fiber raw material and water fed into the refining gap and the axial force of the rotor.
摘要:
The invention relates to a process for preparing micro- and nanocrystailine cellulose material in the presence of an acid. More specifically, the invention relates to a process, in which the cellulose material is hydrolyzed in the presence of an acid in the gas phase while the moisture content of cellulose is between 1% and 80%, the cellulose material is surface-modified, and mech anically treated in order to obtain micro- and/or nanocrystailine cellulose material. The invention also relates to a cellulose product prepared by the said process and the use thereof in food and liquid crystal applications as well as in optical, cosmetic and medical applications.
摘要:
A method for manufacturing cellulosic material includes: introducing cellulose fibers as cellulosic raw material to a system, conveying the cellulose fibers to an extruder comprising a mixing part and/or a refining part, dosing at least one chemical to the system before the extruder and/or in the extruder and performing a reaction between the cellulose fibers and the chemical(s) at least partly in the extruder, wherein the reaction is performed at a consistency of at least 40%, and/or dosing at least one chemical to the system before the extruder and/or in the extruder and mixing the cellulose fibers and the chemical(s) in the mixing part of the extruder, wherein the mixing step is performed at a consistency of at least 40%, and/or refining the introduced cellulose fibers at least partly in the refining part of the extruder, wherein the refining step is performed at a consistency of at least 5%.