249 results about "Black liquor" patented technology

The invention provides a method for calibrating a rolling friction coefficient and surface energy in a process of simulating a ceramic membrane to filter lignin by DEM-CFD, develops a semi-analytical DEM-CFD coupling interface, and on the basis, takes movement and deposition behaviors of lignin particles in a process of filtering black liquor lignin by a single ceramic membrane pore as research objects, and provides a method for calibrating the rolling friction coefficient and the surface energy in the process of simulating the ceramic membrane to filter the black liquor lignin. The capturing mechanism of lignin particles in a ceramic membrane is researched, and it is determined that key factors influencing lignin particle deposition morphology, average coordination number, coordination number distribution and lignin particle deposition structure porosity are rolling friction coefficients and surface energy among lignin particles; the rolling friction coefficient and the surface energy between the lignin particles and the ceramic membrane have little influence on the ceramic membrane; the influence of the rolling friction coefficient among lignin particles and the surface energy parameters on the deposition morphology, coordination number and porosity of the lignin particles is comprehensively considered, calibration work of the rolling friction coefficient and the surface energy parameters is completed, and a powerful tool and accurate simulation parameters are provided for subsequent research of a membrane pollution mechanism.

The invention relates to an oxygen delignification pulping method taking bagasse as a raw material, fine pulp and application of the fine pulp, and belongs to the technical field of pulping and papermaking. The pulping method comprises the following steps: preparing a cooking liquor with the alkali amount of 20-30% from sodium carbonate and sodium hydroxide in a mass ratio of (2-9): 1; mixing bagasse with the cooking liquor, and heating and preserving heat under an oxygen adding condition to obtain cooking slurry; washing and screening the cooked pulp to obtain fine pulp and black liquor; preparing green liquor from the black liquor, adding sodium hydroxide into the green liquor until the alkali consumption is the same as that of the cooking liquor, and recycling the green liquor to the cooking liquor. According to the invention, the used chemical agents are sodium carbonate as a main agent and sodium hydroxide as an auxiliary agent, so that corrosion to equipment is reduced, a causticization reaction process is omitted, harmful solid waste pollution caused by the causticization process is avoided, and direct cyclic utilization of the green liquor is realized. The content of silicon in the black liquor is relatively low, so that the risk of silicon interference in an alkali recovery section is reduced.

The present application discloses a method for preparing a carbon material for a battery, comprising: filtering and concentrating papermaking black liquor to obtain liquid lignin; polymerization: adding a cross-linking agent to the liquid lignin for cross-linking and curing reaction to obtain a lignin polymer solid; pre-oxidation: pre-oxidizing the lignin polymer solid to obtain a lignin-based resin; pre-carbonization: pre-carbonizing the lignin-based resin in a non-oxidizing gas atmosphere to obtain a carbon material precursor 1; gas phase deashing: gas phase deashing the carbon material precursor 1 in a non-oxidizing gas atmosphere under the action of a halogen compound and / or a halogen element to obtain a carbon material precursor 2; calcination: crushing the carbon material precursor 2 and calcining it in a protective atmosphere to obtain a carbon material for a battery. The method of the present application effectively improves the expansion and foaming phenomenon during lignin carbonization, and the obtained carbon material has low ash content, controllable specific surface area, and excellent electrochemical performance. A lignin-based resin as mentioned above is also disclosed.

The invention discloses a ZnO / PES mixed matrix ultrafiltration membrane and a polyaniline-ZnO / PES mixed matrix nanofiltration membrane as well as a preparation method and an application of the ZnO / PES mixed matrix ultrafiltration membrane and the polyaniline-ZnO / PES mixed matrix nanofiltration membrane. PES is used as an organic polymer, PEG1500 is used as a pore-foaming agent, ZnO is used as a nano filler, and the ZnO / PES composite ultrafiltration membrane is prepared through a non-solvent induced phase inversion method. The preparation method comprises the following steps: synthesizing a polyaniline coated ZnO nano composite material, blending zinc nitrate hexahydrate in ammonia water with a polyaniline solution to form a nano composite structure, and preparing the polyaniline-ZnO / PES mixed matrix nanofiltration membrane by taking the synthesized nano composite particles as a filler. According to the mixed matrix membrane technology, alkali and lignin in the black liquor can be directly recovered, compared with alkali recovery through a combustion method, the mixed matrix membrane technology has the advantages of being easy to operate, not complex in process, low in investment cost, small in occupied area, low in energy consumption, good in environmental compatibility and the like, and meanwhile subsequent high-valued comprehensive utilization can be conducted on lignin.

The invention belongs to the fields of biochemical engineering, straw resource comprehensive utilization, three-element separation and synthetic biological fermentation engineering and biomass energy, and discloses high-solid-content plant-derived fulvic acid produced by using humulus lupulus and a production process. The invention discloses a production process of plant-derived fulvic acid, which comprises the following steps: adding a core additive containing humulus lupulus, and mixing with ammonium sulfite to obtain a cooking liquid medicine; and mixing the raw materials with the cooking liquid medicine, cooking, extracting, separating and concentrating to obtain the fulvic acid product concentrated black liquor with high solid content. According to the method, the solid content or dry content of the plant-derived fulvic acid can be increased, the solid content of the existing similar product fulvic acid in the market is higher, the detection value is generally 47-57%, and according to the technical scheme provided by the invention, the solid content of the plant-derived fulvic acid exceeds 75%, and the increase amplitude exceeds 40%.

The invention relates to a hydroxylated lignin / silicon dioxide composite modified styrene-butadiene rubber master batch as well as a preparation method and application thereof, and belongs to the technical field of biomass energy and chemical industry. The preparation method of the hydroxylated lignin / silicon dioxide composite modified styrene-butadiene rubber master batch comprises the following steps: washing industrial lignin with acidic water to obtain filter residues, mixing the filter residues with a sodium hydroxide solution, and carrying out a heating reflux reaction to obtain lignin black liquor; polyethylene glycol is heated and melted, a catalyst and epoxy alkyl halide are added for a reaction, and halogenated alcohol is obtained; mixing the lignin black liquor and halogenated alcohol, and stirring for reaction to obtain hydroxylated lignin; mixing a silicate solution, a silicon dioxide dispersing aid, hydroxylated lignin and styrene-butadiene latex, and performing acid precipitation, aging, water washing, soaking and drying to obtain the water-based paint. Industrial lignin, silicate and styrene-butadiene latex are adopted as raw materials, the hydroxylated lignin / silicon dioxide composite modified styrene-butadiene rubber master batch with excellent mechanical properties is prepared, waste biological resources are developed and utilized, and the process is simple.

The invention discloses a method for preparing a multi-scale nano lignin waterproof and oil-proof agent by using alkaline pulping black liquor and application of the multi-scale nano lignin waterproof and oil-proof agent, and belongs to the technical field of bio-based waterproof and oil-proof agents. According to the preparation method, the alkaline pulping black liquor is used as a raw material, multi-scale nano lignin with the particle size of 200-1500 nm is directly prepared through an acid precipitation method, and the multi-scale nano lignin is compounded with starch to prepare the multi-scale nano lignin waterproof and oil-proof agent. Paper is coated with the multi-scale nano lignin waterproof and oil-proof agent in a double-layer mode, the Cobb 60 value of raw paper can be reduced to 17.71 g / m < 2 > from 62.14 g / m < 2 >, the Kit value is increased to 10 grade from 0 grade, the tensile index is increased to 55.96 Nm / g from 41.11 Nm / g, and the waterproof performance, the oil-proof performance and the mechanical performance of a paper coating are all remarkably improved; the preparation method is simple, the raw materials are wide in source, and the important strategic demand of sustainable development of the material industry in China is met.

The invention belongs to the technical field of green chemistry and sustainable chemical engineering, and discloses a method for recovering an acidic eutectic solvent by combining anti-solvent precipitation with activated carbon adsorption. Water-insoluble high-molecular-weight lignin in the deep eutectic solvent black liquor is removed by an anti-solvent precipitation technology, and then residual low-molecular-weight water-soluble lignin and polysaccharide in the solution are further adsorbed and removed by using activated carbon with high specific surface area and rich pore structure; and the eutectic solvent with high purity and unobviously changed structure is recovered. The method is suitable for various acidic deep-eutectic solvents, the operation is simple, water and activated carbon in the recovery process can be repeatedly used, and the obtained water-insoluble lignin, water-soluble lignin and polysaccharide have high application value.

The invention provides a method for researching membrane pollution of lignin particles in porous ceramic membrane filtration, which simulates the process of filtering black liquor lignin by a porous ceramic membrane based on a developed semi-analytical DEM-CFD coupling interface. The method mainly studies the formation mechanism of membrane pollution and the type of membrane pollution in the process of filtering black liquor lignin by the porous ceramic membrane, analyzes the influence of lignin particle concentration and particle size and black liquor flow velocity on the porous ceramic membrane filtration process, and further obtains the influence of lignin particle concentration and particle size and black liquor flow velocity on membrane pollution. And theoretical basis and microscopic information are provided for selection of subsequent membrane pollution control methods.

The invention belongs to the pulping and papermaking industry, and particularly relates to a replacement type continuous cooking method and device, which is characterized in that when a fiber raw material is cooked and pulped, firstly, raw material fibers are subjected to single-stage or multi-stage preimpregnation by using cooked concentrated black liquor, so that residual liquor and heat in the black liquor are fully utilized; and then replacing the black liquor carried by the pre-impregnated raw material fiber by using a cooking liquid medicine with relatively high medicine concentration, rapidly cooking the replaced raw material fiber into pulp under relatively high medicine concentration, pressure and temperature, and sending the pre-impregnated black liquor to a black liquor treatment process. According to the method and the device, residual liquid medicine and heat in the black liquor after cooking can be fully utilized, energy consumption and medicine consumption generated in the fiber cooking stage can be greatly reduced, the concentration of the black liquor subjected to black liquor removal treatment can be improved, the method and the device particularly accord with pulping characteristics of non-wood fibers, and the fiber cooking cost, especially the pulping cost of the non-wood fibers, can be greatly reduced.

The invention discloses a high-conductivity hard carbon composite material as well as a preparation method and application thereof, and belongs to the technical field of material chemistry. The preparation method of the high-conductivity hard carbon composite material comprises the following steps: pre-oxidizing a hard carbon precursor in an air atmosphere to obtain a pre-oxidized precursor; crushing the pre-oxidized precursor, and pre-carbonizing the crushed pre-oxidized precursor in an inert atmosphere to obtain a pre-carbonized precursor; mixing the pre-carbonized precursor with a dispersing agent, carbon nanotube slurry, a binder and a solvent, and grinding to obtain black liquor; and drying the black liquor, and performing high-temperature carbonization in an inert atmosphere to obtain the high-conductivity hard carbon composite material. The preparation method is simple to operate, low in cost and easy for large-scale production, the conductivity of the hard carbon negative electrode material can be remarkably improved, and the high capacity and the cycling stability of the hard carbon negative electrode material can be maintained.

The present application relates to biomass high-value utilization technical field, more specifically to a kind of papermaking by-product black liquor high-value water phase preparation lignin amine cationic surfactant method, comprising the following steps: pulping black liquor is adjusted pH with acid or alkali, centrifugal to take upper clear liquid, add epoxy chloropropane, temperature is raised to certain temperature and is reacted for 30min.Then, add amine reagent and react for a certain time, after cooling, centrifugal, wash after the lower layer precipitate is dried to obtain lignin amine cationic surfactant.The present application not only can make papermaking by-product black liquor waste into treasure-high-value water phase synthesis lignin amine cationic surfactant, and the preparation process of the lignin amine cationic surfactant is simple, energy consumption is low, the whole process is green, no waste water discharge, without black liquor purification, without adding formaldehyde, also without alkali recovery;Easy to realize industrial production, with broad market prospect.

Methods, apparatuses, and systems for extracting lignin from non-wood black liquor are disclosed. The non-wood black liquor is heated to a first temperature to degrade hemicelluloses contained therein. The liquid is then cooled to a second temperature. The pH of the cooled liquid is chemically reduced to precipitate lignin from the liquid. The liquid is filtered to separate the precipitated lignin from the liquid.

The application discloses a preparation method of a pesticide lignosulfonate sodium dispersant composition and belongs to the technical field of dispersants. The method comprises the following steps: S1, taking papermaking black liquor as raw material, performing standing precipitation, flocculation precipitation, membrane concentration and acid precipitation treatment to obtain purified lignin; S2, adding the purified lignin into water, adjusting the pH of the system to 10-11, then adding hydrogen peroxide to perform pre-oxidation, then adding formaldehyde and sodium sulfite to perform sulfomethylation reaction, and adding formaldehyde to perform polycondensation reaction; cooling and discharging, and performing spray drying to obtain lignosulfonate sodium; and S3, adding the lignosulfonate sodium and 1-ethyl-3-methyl imidazolium L-lactate into water and stirring and uniformly mixing, adding stevioside to perform ultrasonic treatment, forming a homogeneous system, and performing spray drying to obtain the pesticide lignosulfonate sodium dispersant composition. The lignosulfonate sodium dispersant composition can effectively improve the pesticide dispersion stability and pesticide biological activity, and meets the pesticide use requirement.

This invention discloses a rice straw-based liquid mulch film emulsion, its preparation method, and its application. The preparation method includes: treating pretreated rice straw with an alkaline solution in sodium hydroxide to obtain rice straw fibers and a silicon-containing black liquor; washing and bleaching the rice straw fibers to obtain bleached rice straw fibers; allowing the silicon-containing black liquor to stand, adjusting the pH value, and allowing it to stand again to obtain a silicon-containing dispersion; mixing and activating the bleached rice straw fibers with an alkaline alcohol solution, followed by etherification with chloroacetic acid to obtain carboxymethyl cellulose; mixing polyvinyl alcohol and carboxymethyl cellulose solutions, adding the silicon-containing dispersion under stirring, and then adding water to obtain the rice straw-based liquid mulch film emulsion. The rice straw-based liquid mulch film emulsion prepared by this invention can be used for soil covering in cultivated soils, exhibiting excellent film-forming strength, toughness, light-blocking properties, and soil cover adaptability. It has a wide range of raw material sources, a simple preparation process, and is suitable for large-scale promotion.

The present invention discloses a sodium ion battery hard carbon material, a preparation method thereof, and a sodium ion battery using the hard carbon material. The hard carbon material is a composite porous material inlaid with hollow porous spheres and porous carbon sheets. Compared with the prior art, the advantages of the present invention are: a method for preparing sodium ion hard carbon materials from concentrated papermaking black liquor in a short process using spray pyrolysis, using spray pyrolysis to construct a precursor material with a hollow porous spherical structure; using an aqueous solution to collect the precursor material, and removing impurities through solid-liquid separation and washing; and then further regulating the microstructure of the carbon material through two-stage heat treatment to obtain a hard carbon negative electrode material with high specific capacity, excellent rate performance, and cycle stability. Using the hard carbon material as the negative electrode, a high-energy-density sodium ion battery is prepared.

The invention relates to a composition comprising a hydraulic binder, optionally a fly ash aggregate, and at least one additive, wherein the additive is a combustion residue obtained from the combustion of black liquor, and wherein the additive is present in a concentration of 0.01% to 6.0% by weight based on the total amount of the composition. The invention further relates to a building material containing this composition.

A preparation method of the biomass-based zwitterionic surfactant comprises the following steps: adjusting the pH value of pulping black liquor by using acid or alkali, centrifuging to take supernatant liquid, adding epoxy chloropropane, heating to a certain temperature, and reacting for a certain time. And then, adding an amine reagent to react for a certain time to obtain a brownish black biomass-based zwitterionic surfactant solution, and drying to obtain a biomass-based zwitterionic surfactant solid. According to the method, the biomass-based zwitterionic surfactant can be directly synthesized from the high-pollution pulping black liquor in a high-valued aqueous phase mode, the preparation process of the biomass-based zwitterionic surfactant is simple and low in energy consumption, the whole process is green and environmentally friendly, the black liquor does not need to be purified, organic reagents such as alcohols and formaldehyde do not need to be added, alkali recovery is not needed, and the method is suitable for industrial production. Commercialized production is easy to realize. The biomass-based zwitterionic surfactant can be applied to the fields of textile softeners, oil emulsifiers, bactericides, disinfectants and the like, and has a wide market prospect.

The present invention relates to a method for preparing cross-linked lignin in the form of particles using hydrothermal treatment with a liquid made from black liquor, comprising lignin and a cross-linking agent or a precursor thereof, and having an electrical conductivity of more than 15 mS / cm, preferably more than 25 mS / cm to 400 mS / cm. The present invention also relates to cross-linked lignin produced using the above-mentioned method. The present invention also relates to cross-linked lignin particles having a glass transition temperature Tg of at least 160°C or no glass transition temperature and a STSA surface area of at least 10 m 2 / g. The present invention also relates to rubber articles, in particular industrial rubber articles or tires, comprising cross-linked lignin particles as filler.

The utility model relates to a multistage flash evaporation and vacuum low-temperature negative-pressure black liquor concentration system based on industrial waste heat, which belongs to the technical field of flash evaporation and comprises at least one heat exchange unit and at least two flash evaporation units sequentially connected in series. The concentration medium outlet of the flash evaporation unit located at the last effect is communicated with the concentration medium inlet of the heat exchange unit equivalent to the flash evaporation unit of the last effect located at the last effect, and when the number of the heat exchange units is at least two, the heat exchange units are sequentially connected in series. The flash evaporation unit located at the first effect communicates with the heat exchange unit equivalent to the flash evaporation unit located at the first effect through a heating unit. The concentration medium generated by the last-effect flash evaporation unit flows back to the previous-effect heat exchange unit to serve as a heat source, energy recycling is achieved, the requirement for external heat input is reduced, and therefore the energy efficiency of the whole system is improved; the plurality of heat exchange units which are sequentially connected in series can more effectively utilize temperature gradient to transfer heat, so that the heat can be more uniformly transferred to each flash evaporation unit, and the heat transfer effect is enhanced.

The invention discloses a method for preparing a water-soluble lignin chelated calcium fertilizer from concentrated black liquor, and belongs to the technical field of chelated fertilizer preparation. The technical key point of the invention is that the novel environment-friendly calcium fertilizer is prepared through CO2 acid precipitation and calcium chloride chelation based on the hydrophilicity and chelation of small molecule lignin in the black liquor. The method mainly comprises the following steps: concentrating the black liquor until the solid content is 30-50%, introducing CO2 gas under a certain condition to carry out an acidification reaction, carrying out centrifugal separation to obtain a precipitate, adding a calcium chloride solid into a supernatant while stirring until no precipitate is separated out, carrying out centrifugal separation to obtain a precipitate, adding absolute ethyl alcohol into the supernatant according to a volume ratio of 1: 1, uniformly mixing, and centrifuging to obtain a precipitate; and washing the precipitate part with a 50% ethanol solution, and drying to obtain the water-soluble lignin calcium fertilizer. The invention provides a preparation technology of the water-soluble lignin chelated calcium fertilizer, which has the advantages of simple and efficient preparation process, low cost and great industrial potential, and opens up a convenient and effective new conversion path for converting the natural polymer material lignin into the efficient fertilizer.

The invention discloses a preparation method of a nitrogen-sulfur co-doped lignin-based hierarchical porous carbon material and supercapacitor energy storage application, and belongs to the technical field of preparation methods and application of porous carbon materials, and the preparation method comprises the following steps: (1) dropwise adding an ammonium sulfate solution into sulfate pulping black liquor, and adjusting the pH value, after standing reaction, drying to obtain ammonium sulfate precipitated lignin; (2) uniformly mixing lignin with potassium tartrate and potassium nitrate, drying and grinding to obtain a mixture; and (3) pyrolyzing the mixture in an inert atmosphere, washing the carbonized product with dilute acid, filtering, and drying to obtain the porous carbon material. Potassium tartrate promotes formation of graded pores through the mild pore-forming effect, and the foaming effect of potassium nitrate can inhibit formation of coal tar and excessive carbon skeleton etching in the pyrolysis process. The supercapacitor electrode material prepared from the porous carbon has high specific capacitance, excellent cycling stability and high energy density.

The invention provides a biomass and coal co-gasification papermaking energy supply system and method. The system is composed of a screening unit, a smashing unit, a primary gasification unit, a pyrolysis unit, a secondary gasification unit, a water gas conversion unit, an acidification unit, a carbonization unit, an alkalization unit, a fuel cell and the like. Low-quality wood and bark resin are screened out from papermaking raw materials to serve as biomass raw materials and smashed into biomass powder, part of the biomass powder and coal are co-gasified, part of the biomass powder is directly pyrolyzed, part of the biomass powder is combusted, and biomass ash is generated to serve as a gasification process catalyst; black liquor generated by the pulping and bleaching unit is converted into coarse carbon through the acidification and carbonization unit, part of the coarse carbon is converted into activated carbon through the alkalization and activation unit and serves as an adsorbent of the carbonization unit, part of the coarse carbon and coal are converted into CO through two-stage gasification and converted into hydrogen after water-gas conversion, and the hydrogen serves as a fuel cell raw material to generate electric energy; biomass is utilized in multiple modes, so that energy is fully utilized.

Compositions and methods for the removal and prevention of scale in pulp mills in a continuous and real-time process. More particularly the composition includes one or more chelating ligands, one or more copolymers, and one or more surfactants. The scale removing composition is added to the black liquor stream in pulp and paper processes to remove scaling, such as scaling from calcium carbonate, from surfaces in contact with the black liquor stream, such as in digestors and evaporators.

A paper mill black liquor waste heat utilization system belongs to the technical field of energy conservation and environmental protection. The utility model solves the problem that the residual heat cannot be effectively utilized due to environmental pollution caused by direct flash evaporation of the black liquor in the existing paper mill. Comprising a reboiler, a demineralized water system, a black liquor system and a positive pressure steam preparation system, the two ends of a heat release pipe in the reboiler are connected with the black liquor system through a liquid supply pipe and a liquid return pipe respectively, a steam-water side inlet in the reboiler is connected with the demineralized water system, and the positive pressure steam preparation system comprises a steam-water separator and a steam compressor. A steam inlet end and a steam outlet end of the steam-water separator are respectively connected with a steam-water side outlet of the reboiler and a steam inlet of the steam compressor through a negative pressure steam pipeline, and a steam outlet of the steam compressor is connected to a process demand point through a positive pressure steam pipeline. According to the utility model, the waste heat of the black liquor in the paper mill can be utilized, high-quality steam is prepared, the waste heat in the black liquor is recovered, and clean steam is generated and applied to the technological process.

The invention provides a composite geopolymer material as well as a preparation method and application thereof, and belongs to the technical field of geopolymer materials. The method comprises the following steps: providing initial alkalinity and soluble salt ions of a system by using papermaking black liquor ash, providing an aluminum-silicon precursor by using coal gangue powder, obtaining geopolymer slurry with proper rheology through coupling regulation and control of proportion, granularity and water-binder ratio, and forming the geopolymer slurry into a sample blank; then absorbing industrial furnace tail gas by using a composite amine solution to prepare a CO2-rich solution, soaking the sample blank for a short time to enable the CO2-rich solution to uniformly permeate into pores, heating in a medium-low temperature and high humidity environment to promote the CO2-rich solution to slowly release CO2 into the plate, and synchronously evolving with a gel network to form uniform and stable carbonate microcrystals and compact pore walls, so as to achieve the purpose of improving the performance of the plate. According to the process, the surface layer density and the size stability are rapidly improved, meanwhile, CO2 resource solid storage and amine liquid closed-loop circulation are achieved, NaOH / water glass does not need to be additionally added, the corrosivity and the safety risk are low, and the process is suitable for continuous industrial production.

The invention discloses a lignin-styrene-butadiene latex core-shell material, a preparation method thereof and application of the lignin-styrene-butadiene latex core-shell material in a PE composite material, and the preparation method comprises the following steps: dissolving lignin in an organic solvent to obtain a lignin solution; the preparation method comprises the following steps: adding an emulsifier and distilled water into a reaction kettle, stirring, dropwise adding a lignin solution to form a stable oil-in-water emulsion, dropwise adding an initiator, styrene and butadiene into the oil-in-water emulsion, carrying out a thermal insulation reaction, and carrying out suction filtration, washing and drying to obtain the lignin-styrene-butadiene latex core-shell material. In addition, the core-shell material, PE, a plasticizer, a lubricant, an anti-blocking agent and the like are subjected to blending, extrusion granulation and film blowing forming, and the PE composite material is prepared. The core-shell structure effectively shields polar functional groups on the surface of the lignin, and obviously improves the compatibility and dispersity of the lignin in a PE matrix, so that the mechanical property of the composite film is enhanced, the surface defects are obviously reduced, and the high-valued resource utilization of the lignin in the papermaking black liquid is realized.

The invention discloses a method for pulping by using sugarcane leaves, and belongs to the technical field of pulping and papermaking. The method comprises the following technical steps: (1) pretreatment of sugarcane leaves: immersing crushed sugarcane leaves into a mixed solution, carrying out microwave irradiation, and filtering to obtain a cooked material; (2) two-stage cooking: putting the cooking material into cooking liquor containing a composite cooking agent, and carrying out first-stage cooking, so as to obtain first slurry; a silicon dispersing agent is added into the first slurry for second-stage cooking, and second slurry is obtained; and (3) pulping: carrying out solid-liquid separation, washing and screening on the second pulp to prepare paper pulp. The method for pulping by using sugarcane leaves has the advantages of high desilicication rate, high lignin removal rate, high cellulose retention rate, small amount of alkali (sodium hydroxide) required in the production process, low viscosity of black liquid, low equipment scaling possibility, low equipment cleaning frequency, high production efficiency and low production cost.

This invention discloses a method for preparing hard carbon derived from the aerial roots of banyan trees, belonging to the field of new energy materials technology. The method includes the following steps: Step 1: Freshly cut banyan aerial roots are washed, dried, crushed, and sieved; Step 2: Choline chloride (ChCl) and lactic acid (LA) are mixed in a certain proportion to prepare DES; Step 3: The DES from Step 2 is mixed with the banyan aerial root powder from Step 1 and reacted, then subjected to delignification. The delignified black liquor is washed with anhydrous ethanol and deionized water and filtered to obtain a filter cake, which is then dried in an oven; Step 4: The filter cake from Step 3 is ground into powder and calcined at a medium-low temperature to obtain pre-carbonized banyan aerial root powder; Step 5: The pre-carbonized powder from Step 4 is calcined at a medium-high temperature, acid-washed, and dried to obtain banyan aerial root-derived hard carbon. This invention discloses a green, environmentally friendly, and high-performance method for preparing derived hard carbon, applicable to battery anode materials, realizing the high-value utilization of biomass waste.

The invention relates to the technical field of concrete admixtures, in particular to a special polycarboxylic acid water reducing agent for desert sand concrete and a preparation method of the special polycarboxylic acid water reducing agent. The special polycarboxylic acid water reducing agent for the desert sand concrete comprises the following components: a high-performance polycarboxylic acid water reducing agent and modified paper pulp black liquor, the high-performance polycarboxylate superplasticizer is prepared through a polymerization reaction of a vinyl polyether macromonomer, unsaturated carboxylic acid and a functional monomer under the action of an initiator and a chain transfer agent. According to the special polycarboxylic acid water reducing agent for the desert sand concrete, the high-performance polycarboxylic acid water reducing agent and the modified paper pulp black liquor are compounded and applied to the desert sand concrete, the initial fluidity of the concrete is good, the slump retaining property is good, the water retention property, the wrapping property and the cohesiveness of the concrete are good, and segregation and bleeding phenomena do not exist; the problems that the slump loss of a desert sand concrete mixture is fast and the desert sand concrete mixture is prone to bleeding and segregation due to the fact that the desert sand is large in fine powder amount and poor in gradation are solved.