19 results about "Dissolving pulp" patented technology

The preparation method of the environment-friendly anti-aging packaging base paper comprises the following steps: taking softwood pulp and dissolving pulp, pulping for the first time, adding microcrystalline cellulose, and stirring to form first pulp; adjusting the pH value of the first slurry to be neutral, adding a water-soluble chitosan-polyphenol compound, and pulping for the second time to form second slurry; adding oxidized sodium alginate into the second pulp, and pulping for the third time to form third pulp; forming raw paper according to a papermaking process; the invention further provides packaging base paper which has the characteristic of good anti-aging performance. Softwood pulp and dissolving pulp are used as papermaking raw materials, microcrystalline cellulose, a water-soluble chitosan-polyphenol compound and oxidized sodium alginate are used, a pulping process which is sequentially added according to a sequence is formed, a stable fiber network is constructed layer by layer, and a mechanism of skeleton supporting, covalent crosslinking and antioxidant end capping is formed. The anti-aging performance of the raw paper is improved.

The invention belongs to the technical field of xylooligosaccharide preparation, and discloses a method for co-producing dissolving pulp and xylooligosaccharide by using bagasse. Comprising the following steps: (1) mixing a hydrogen bond acceptor, an alkaline hydrogen bond donor and a protective agent, and heating and stirring to prepare an alkaline eutectic solvent; (2) adding the bagasse into an alkaline eutectic solvent, and heating and stirring for reaction to obtain a reaction mixture; (3) carrying out solid-liquid separation on the reaction mixture, washing a solid component to be neutral to obtain holocellulose, and collecting a washing solution; mixing the washing solution and the liquid component, adding into absolute ethyl alcohol, standing and precipitating, then carrying out solid-liquid separation, and washing and freeze-drying the solid precipitate to obtain hemicellulose; (4) respectively performing enzymolysis on holocellulose and hemicellulose by adopting xylanase, collecting enzymatic hydrolysate and enzymolysis residues, merging the enzymatic hydrolysate, and treating to obtain xylooligosaccharide; washing and freeze-drying holocellulose enzymolysis residues to obtain the dissolving pulp. The alkaline eutectic solvent is used for assisting enzymolysis to obtain the dissolving pulp and the xylooligosaccharide.

The invention particularly relates to a dissolving pulp production process which comprises the following steps: washing and soaking wood chips or cotton linters, and naturally draining to obtain a pretreated raw material; adding adjusting water into the pretreated raw material, then adding sodium sulfite, mixing and stirring, heating and preserving heat, and extracting pre-hydrolysis waste liquid to obtain semi-slurry; the ratio of the absolute dry mass of the pretreated raw materials to the volume of the adjusting water is 1: (5-8); in terms of SO2, the use amount of sodium sulfite is 2%-4% of the absolute dry mass of the pretreated raw material; the heating and heat preservation temperature ranges from 150 DEG C to 160 DEG C, and the heat preservation time ranges from 90 min to 120 min; carrying out sulfate cooking on the semi-slurry to prepare coarse slurry and cooking black liquor; the coarse pulp is bleached, pulped and sieved by adopting an OD0EOPD1 section sequence, and the dissolving pulp is prepared. According to the method, the quality of the dissolving pulp is remarkably improved by adopting sodium sulfite to prehydrolyze the dissolving pulp, the high-end application requirements of cellulose acetate, Lyocell fibers and the like can be met, the vacuum pulp washing link of semi-pulp after prehydrolysis is omitted, the pulp wastage rate is reduced, the MVR evaporator utilizes secondary steam compression reuse, and the water resource utilization rate is improved.

The invention provides water-resistant bobbin base paper and a process thereof, and the bobbin base paper comprises the following components in parts by weight: 80-120 parts of a natural wood fiber raw material, 3-9 parts of chitosan, 4-12 parts of a waterproof emulsion, 3-9 parts of a treating agent, 2-6 parts of a defoaming agent, 1-3 parts of a sterilizing agent and 2-4 parts of a cross-linking agent, the natural wood fiber raw material is one or a mixture of more of commercial paper pulp, waste paper and straw agricultural wastes; the commercial paper pulp is one or more mixed pulp of bleached softwood pulp, bleached hardwood pulp, dissolving pulp or unbleached paper pulp, the preparation process is simple, the prepared bobbin body paper has the advantages of high strength, water resistance and easiness in printing, meanwhile, the bobbin body paper also has excellent waterproof performance, and the service life of a bobbin paper product is prolonged.

The invention relates to the technical field of environment-friendly containers, and particularly discloses a plastic-free container meeting SUPD plastic-free requirements, the plastic-free container comprises a main body structure and an auxiliary structure, the main body structure and the auxiliary structure are both made of composite paperboards, and each composite paperboard comprises a base paper layer and a regenerated cellulose barrier layer arranged on the surface of the base paper layer; the regenerated cellulose barrier layer is a compact film formed by regenerating dissolving pulp cellulose fibers after being dissolved in a phenolic imidazole [C2mim] [Oh] ionic liquid (IL) and N, N-dimethylformamide (DMF) mixed solvent system, and the plastic-free container is free of any plastic component and conforms to the European SUPD plastic-free definition; the plastic-free container meeting the SUPD plastic-free requirement has the advantages that the environmental protection property comprehensively reaches the standard, the barrier property is excellent, the heat sealing forming is efficient and stable, the cost and process advantages are remarkable, and the like.

The invention discloses a production method and application of bamboo reed dissolving pulp. The production method of the dissolving pulp comprises the following steps: preparing materials, slicing bamboo reeds, tearing and softening, removing dust, cleaning and dehydrating; keeping the temperature at 150-175 DEG C for 90-150 minutes, and carrying out steam hydrolysis; a sulfite solution is adopted, cooking is conducted for 90-150 min at the temperature of 160-180 DEG C till the pH end point ranges from 5.5 to 6.5, and the hardness K of feed liquid ranges from 15 to 21; and then carrying out a coarse pulp washing and screening process, an oxygen delignification process and an A-DO-EOP-D1-D2 bleaching process so as to carry out multi-stage bleaching on the pulp. The bamboo reed is used as a raw material instead of wood, so that the wood is saved, the cost is reduced, the black liquor in the preparation process can be used as fulvic acid fertilizer, secondary solid waste pollution is avoided, and the method is environment-friendly and efficient in utilization. The dissolving pulp prepared by the method meets the standard and has antibacterial property when being applied to fiber materials.

The present application relates to a kind of weakly hydrophilic low back permeable non-woven fabric preparation method, mainly including the following sequentially performed steps: (1) preparation of hydrophobic modified viscose fiber: dissolved pulp with coniferous wood and broadleaf wood dissolved pulp is prepared viscose staple fiber;Again, through water-repellent finishing and other processes, obtain hydrophobic modified viscose fiber;(2) preparation of weakly hydrophilic low back permeable non-woven fabric: hydrophobic modified viscose fiber is sequentially subjected to opening, carding and water jet processing steps, then through hydrophilic finishing and drying, weakly hydrophilic low back permeable non-woven fabric is obtained.The present application solves the shortcomings that existing non-woven fabric is difficult to simultaneously meet the liquid rapid infiltration and low back permeation amount, by using the preferred water-repellent finishing liquid to hydrophobically modify the viscose fiber first, then using the preferred hydrophilic finishing liquid to hydrophilically modify, weakly hydrophilic low back permeable non-woven fabric is obtained, which has the characteristics of biodegradable, can make liquid rapid infiltration and low back permeation amount.

The invention belongs to the technical field of dissolving pulp preparation, and discloses a method for removing metal ions in dissolving pulp and the dissolving pulp. According to the invention, a specifically prepared organic acid pickling solution is adopted to carry out pickling complexing treatment on the slurry. After treatment, the removal effect of metal ions in the slurry is remarkable, and the following index requirements are met: the content of iron ions is less than or equal to 5mg / kg, the content of calcium ions is less than or equal to 30mg / kg, the content of magnesium ions is less than or equal to 20mg / kg, and the content of copper ions is less than or equal to 5mg / kg. The method particularly has an excellent removal effect on firmly combined iron ions, the highest removal rate reaches 89.9%, and the content of the iron ions is reduced from higher than 45 mg / kg to lower than 5 mg / kg, so that the high-purity slurry is obtained. The obtained slurry is beneficial to subsequent dissolution and spinning processes, and the pickling process has slight influence on the polymerization degree of the slurry and can be maintained within a reasonable range.

The invention relates to a chitosan quaternary ammonium salt lyocell fiber and a preparation method thereof. The preparation method comprises the following steps: 1) preparing raw materials, namely mixing needlebush dissolving pulp and hemp dissolving pulp to obtain mixed pulp; preparing an active chitosan quaternary ammonium salt into an aqueous solution, and adjusting the pH value to 8-10 to obtain a grafting solution; 2) activating and grafting the pulp: adding the mixed pulp into the grafting solution, and reacting at 60-80 DEG C for 3-24 hours to obtain activated pulp; 3) washing and drying to obtain modified pulp; and 4) dissolving and spinning: dissolving the modified pulp to prepare a spinning solution with the cellulose mass fraction of 8-15%, and carrying out dry-jet wet-spinning molding. The obtained modified lyocell fiber has the advantages of non-dissolution antibacterial property, supply chain safety improvement and consideration of mechanical property and hand feeling, the antibacterial requirement of a finished product use end is met, the bacterium growth risk of finished product storage and processing is reduced from the product, and the dual effects of production bacterium control and finished product bacterium resistance are achieved.

A process to manufacture dissolving pulp grade cellulose comprises providing a lignocellulosic material; providing a modified Caro's acid; exposing the lignocellulosic material to the modified Caro's acid for a period of time sufficient to allow the modified Caro's acid to delignify the lignocellulosic material and yield a solid cellulosic portion and a liquid portion with a high dissolved lignin content. Additional steps include separating the solid cellulosic portion from the liquid portion; exposing the solid cellulosic portion to a caustic solution yielding causticized solids; filtering the causticized solids; re-slurrying the causticized solids and neutralizing such to yield a dissolving pulp cellulose; and washing said dissolving pulp cellulose with water

The invention provides high-quality dissolving pulp and a preparation method thereof, and belongs to the technical field of dissolving pulp, the preparation method comprises the following steps: S1, loading wood flour into a spherical digester, adding a sodium hydroxide solution, controlling temperature and pressure, preserving heat and cooking to obtain coarse pulp; s2, deionized water is added into the crude pulp, the pH is adjusted, xylanase is added, then an activating auxiliary agent is added, activating treatment is conducted, pretreated pulp is obtained, and the activating auxiliary agent is a mixture of hydrosulfite and citric acid; s3, a chelating agent is added into the pretreated slurry, purified slurry is obtained, and the chelating agent is sodium tripolyphosphate cross-linked modified chitosan; and S4, carrying out bleaching treatment on the purified pulp by adopting chlorine dioxide, and obtaining the high-quality dissolving pulp after the bleaching is completed. According to the high-quality dissolving pulp prepared by the method, the alpha cellulose content can reach 94.2% or above, the iron content is 20 ppm or below, and the whiteness is 85% or above.

The application discloses a preparation method of high-strength Lyocell regenerated cellulose fiber, and aims to solve the problem of insufficient mechanical strength of existing regenerated cellulose fiber caused by too wide molecular weight distribution of pulp. The method is characterized in that, through the synergistic effect of a mild pre-hydrolysis kraft (PHK) cooking process and an optimized multi-stage elemental chlorine-free (ECF) bleaching sequence (D0-E-D1), the lignin and hemicellulose are efficiently removed, and the long molecular chain of cellulose is maximally protected; through multi-stage gradient cold alkali extraction and purification treatment, the alkali concentration and low-temperature conditions are accurately controlled, and short-chain cellulose is selectively dissolved, so that the active regulation and narrowing of the molecular weight distribution of cellulose are realized, and a dissolving pulp with high polymerization degree and concentrated molecular weight distribution is obtained. Finally, the high-quality dissolving pulp is used to prepare Lyocell fiber with significantly enhanced mechanical properties through NMMO solvent system dry-jet wet spinning.

A process to manufacture dissolving pulp grade cellulose said process comprising the steps of: o providing a lignocellulosic material; o optionally, comminuting said lignocellulosic material into chips of a particle size no greater than 5 cm o providing a modified Caro's acid, wherein said modified Caro's acid o exposing said lignocellulosic material to said modified Caro's acid at a temperature of less than or equal to 45°C for a period of time sufficient to allow the modified Caro's acid to delignify said lignocellulosic material and yield a solid cellulosic portion and a liquid portion with a high dissolved lignin content; o separating said solid cellulosic portion from said liquid portion; wherein said solid cellulosic portion has the following characteristics: o lignin content below 1%; o hemicellulose content below 15%; and o cellulose content of at least 75%; - exposing said solid cellulosic portion to a caustic solution yielding causticized solids; - filtering said causticized solids; - re-slurrying said causticized solids and neutralizing such to yield a dissolving pulp cellulose; and - washing said dissolving pulp cellulose with water to remove the neutralized salts to obtain a high purity dissolving pulp cellulose having the following characteristics: o over 90% cellulose content; o less than 1% lignin content; o less than 5% hemicellulose content; and o an intrinsic viscosity ranging between 100 – 800 mL / g.

The invention provides a flame-retardant antibacterial skin-friendly functional lyocell fiber and a preparation method thereof, and belongs to the field of fiber materials.The flame-retardant antibacterial skin-friendly functional lyocell fiber is prepared by preparing microencapsulated melamine phosphate powder and an amino acid cross-linked phytic acid solution, infiltrating the microencapsulated melamine phosphate powder into the amino acid cross-linked phytic acid solution, curing, washing and drying, and the flame-retardant antibacterial skin-friendly functional lyocell fiber is obtained. Modified flame retardant powder is obtained; dissolving pulp in an NMMO aqueous solution, adding a stabilizer, a cross-linking agent and the modified flame retardant powder, and mixing and reacting to obtain a spinning solution; and performing ultrasonic treatment and oil bath on the spinning solution, and spinning to obtain the flame-retardant antibacterial skin-friendly functional lyocell fiber. The phytic acid and the microencapsulated melamine phosphate are utilized to modify the lyocell fibers through crosslinking and curing, efficient, durable, flame-retardant and antibacterial effects are achieved, the preparation process is simple, and the lyocell fibers can be widely applied to the fields of close-fitting household textile articles, medical textile articles and the like.

The invention discloses a preparation method of a high-strength Lyocell regenerated cellulose fiber, and aims to solve the problem of insufficient mechanical strength of the existing regenerated cellulose fiber caused by over-wide molecular weight distribution of pulp. According to the method, through the synergistic effect of a mild prehydrolysis sulfate method (PHK) cooking process and an optimized multi-section elemental chlorine-free (ECF) bleaching sequence (D0-E-D1), lignin and hemicellulose are efficiently removed, and meanwhile a cellulose long molecular chain is protected to the maximum extent; and through multi-section gradient cold alkali extraction and purification treatment, the alkali concentration and low-temperature conditions are accurately controlled, and short-chain cellulose is selectively dissolved out, so that active regulation and narrowing of molecular weight distribution of cellulose are realized, and the dissolving pulp with high polymerization degree and concentrated molecular weight distribution is obtained. Finally, the high-quality dissolving pulp is used for preparing the Lyocell fiber with remarkably enhanced mechanical properties through NMMO solvent system dry-jet wet spinning.

This invention provides a method for preparing Lyocell fibers using ordinary chemical pulp. The method involves first pretreating the ordinary chemical pulp, then purifying the pretreated pulp using two stages of dilute NMMO solutions of different concentrations to remove hemicellulose. The purified pulp is then spun using a dry-jet wet-spinning process to obtain Lyocell fibers. The resulting Lyocell fibers possess the same or some superior properties as Lyocell fibers prepared using dissolving pulp. This invention provides a simple, green, and environmentally friendly preparation method that can be effectively combined with existing Lyocell fiber manufacturing processes, significantly reducing the manufacturing cost of Lyocell fibers.

The invention discloses a method for preparing lactic acid by using mannose, which comprises the following steps: dissolving mannose and a metal salt catalyst in water, enabling mannose to come from the preparation process of softwood dissolving pulp, and then carrying out hydrothermal reaction to obtain lactic acid. The method for preparing lactic acid by using mannose has the advantages of simple preparation process, short production cycle, high catalytic efficiency of the catalyst, high production efficiency, low production cost, green and environment-friendly solvent and the like, and can realize resource utilization of the byproduct mannose generated in the preparation process of the softwood dissolving pulp; the method is suitable for large-scale industrial application.

The invention belongs to the technical field of pulping and papermaking and high-value utilization of biomass, and particularly relates to a method for efficiently preparing furfural by using sugar components in dissolving pulp prehydrolysate. Comprising the following steps: (1) adding dilute sulphuric acid into pre-hydrolysate, putting into a high-pressure sterilization pot, carrying out hydrolysis reaction, and centrifuging I to obtain supernate I; (2) adding activated carbon into the supernate I obtained in the step (1) for adsorption treatment, and centrifuging II to obtain supernate II; (3) putting the supernate II obtained in the step (2) and an organic solvent into a reaction kettle; and (4) adding FePO4 and NaCl into the mixed solution obtained in the step (3), reacting, and distilling and purifying the obtained organic phase to obtain furfural. The invention provides a green and efficient path, not only realizes resource utilization of the pre-hydrolysate, but also lays a foundation for industrial application of furfural, and has remarkable economic and environment-friendly advantages.

According to an exemplary aspect of the invention, a method for producing cellulose fibers or membranes is provided, the method comprising the step of: dissolving pulp in a cationic 1,5,7-triazabicyclo[4.4.0]dec-5-enium [TBDH] selected from the group consisting of formulas a), b), and c). + In partial and anionic ionic liquids, to provide spinning solutions, wherein R, R 2 R 3 R 4 R 5 R 7 R 8 R 9 and R 10 Each is either H or an organic group, and X ‑ Selected from: halide ions, halide-like ions, carboxyl ions, alkyl sulfite ions, alkyl sulfate ions, dialkyl phosphite ions, dialkyl phosphate ions, dialkyl phosphonite ions, and dialkyl phosphonate ions; extruding the spinning solution through a spinneret to form one or more filaments; and selected from the steps of: spinning cellulose fibers from a solution and extruding cellulose membranes from a solution.