38results about How to "Avoid recycling difficulties" patented technology

This invention discloses a method for preparing levulinic acid by hydrolyzing hexamylose catalyzed by heat-resistant strong-acidic resin. The method comprises: (1) adding 10-400 g/L hexamylose aqueous solution and heat-resistant strong-acidic resin at a weight ratio of (2-20):1 into a pressure reaction kettle, sealing, stirring, heating to boiling under normal pressure, and evacuating for 2-5 min; (2) heating to 120-180 deg.C, and hydrolyzing for 2-16 h; (3) cooling the hydrolysis product to obtain hydrolysis solution. The method utilizes heat-resistant strong-acidic resin as a substitute for liquid inorganic acid as the catalyst, and has such advantages as mild reaction conditions, easy separation of the catalyst, recoverable catalyst, high catalytic activity, and high levulinic acid yield. The method is environmentally friendly, and can avoid the problems of difficult recovery of catalyst, serious pollution and serious corrosion faced by the method utilizing inorganic acid catalyst.

The invention discloses a crystalline high polymer physical foaming material preparation method and is characterized in that the preparation method comprises the following steps: placing crystalline high polymer in an airtight container of which the volume is 25 times or more than 25 times of the total volume of the particles and the temperature T is not less than Tm which is the melting point of the crystalline high polymer and less than Tend which is the temperature at which crystal completely melts, keeping the crystalline high polymer in partial melting state with a little crystal or crystal particles, then injecting 8-20MPa of pressure gas, keeping the temperature and the pressure for 1-30min, then relieving the pressure in a speed of 5-20MPa/s to the normal pressure, taking out the material and cooling to obtain the foaming material. In the preparation method of the invention, the rigidity of the residual crystal particles in the high polymer and the physical crosslinked network are used to limit the free movement of the high polymer chain of the melt so that the high polymer melt can coat the gas, realize crystalline high polymer foaming and solve the problem that the foamability of the crystalline high polymer is poor.

The invention relates to the technical field of wastewater treatment and photoelectric catalytic materials, and discloses an electrochemically modified bismuth vanadate-molybdenum sulfide-cobaltosic oxide catalytic electrode, as well as a preparation method and application thereof. The preparation method comprises the following steps: dispensing a Bi<3+> precursor solution on a conductive substrate, drying and calcining to obtain a BiVO4 pre-substrate film electrode; putting the BiVO4 pre-substrate film electrode in a BiVO4 seed solution, performing hydrothermal reaction, and calcining to obtain a BiVO4 film electrode; electrodepositing the BiVO4 film electrode by using MoS2 precursor solution as a deposition solution and BiVO4 film electrode as a work electrode, and calcining to obtain aBiVO4-MoS2-Co3O4 photoelectric catalytic film electrode; and electrochemically modifying by using a potassium borate solution as a modifying solution and the BiVO4-MoS2-Co3O4 photoelectric catalytic film electrode as a work electrode. The catalytic electrode has relatively high photo-induced electron and hole separation efficiency, and has excellent photoelectric catalytic activity.

The invention relates to a preparation method of compound medical dressing, and belongs to the technical field of biomedical materials. The method comprises preparation of a moisture absorption layer,the preparation of an antibacterial polymer solution, and preparation of the compound medical dressing. According to the method, superfine polymer fiber containing antibacterial agents is rapidly prepared through a centrifugal spinning method, and the superfine polymer fiber in combination with chitosan fiber ensures that the compound medical dressing has an excellent antibacterial function; themedical dressing with excellent antibacterial, hemostatic, moisture absorption and moisture retention properties is prepared through excellent hemostatic property and moisture absorption and moistureretention properties of calcium alginate. The method is simple in technology, low in equipment requirement, convenient to operate and control, high in production efficiency and easy for industrial production.

The invention discloses a composite (BiO)2CO3/C photocatalyst and application thereof, and belongs to the field of photocatalysis materials. Carbon fibers are prepared by adopting bamboo fibers as a carbon source, and (BiO)2CO3 is uniformly loaded on the carbon fibers by utilizing a hydrothermal method. The material is excellent in photocatalysis performance, and especially under the illumination of a xenon lamp, organic pollutants in sewage can be effectively degraded.

The invention relates to a method for synthesizing a mesoporous carbon material. The method comprises the following steps: dissolving a carbon precursor and a template agent in water to form a uniform liquid which is prepared from 0.5-10 mass percent of the carbon precursor, 0.2-2 mass percent of the template agent and the balance of an aqueous liquid; spinning or directly pouring the prepared liquid to the surface of a container to form a coating; putting the coated container in a closed device, and vacuumizing at room temperature to 70 DEG C until the solvent moisture is completely volatilized; further thermally polymerizing and curing the obtained sample at 80-150 DEG C for 10-60 hours; and roasting the cured sample at 600-1000 DEG C under protection of nitrogen atmosphere to obtain the ordered mesoporous carbon material. According to the preparation method, the ordered mesoporous carbon material is synthesized by adopting water as a solvent through an evaporation-induced self-assembly (EISA) method, and the evaporation speed of the solvent is accelerated under slight heating and vacuumizing conditions, so that the problems of solvent reclaiming difficulty, raw material waste and environment pollution caused by adopting organic solvents in the prior art can be avoided.

The invention discloses a method for non column chromatography separation and purification of witloof acid from an Echinacea purpurea extractive. The method comprises the following steps: adding an extract solvent in 3-5% of weighed Echinacea purpurea extractive, and adding acid to regulate the pH to 2-4, carrying out ultrasonic extraction, and centrifuging so as to obtain supernate; adding 0.1-0.3g of inorganic mixed salt in each milliliter of supernate; stirring, carrying out ultrasonic dissolution, and centrifuging so that the solution is divided into upper and lower phases, the volume ratio of the upper phase to the lower phase is 1:(8-12), and the witloof acid is distributed on the upper phase, thereby achieving the separation and enrichment of the witloof acid; and adding chloroformand absolute ethyl alcohol in the upper phase solution for decompression evaporation so as to obtain a deep yellow powder with 25-40% of witloof acid, wherein the volume of the chloroform and absolute ethyl alcohol is 2-3 times as much as that of the upper phase solution. By using the method in the invention, the purity of the witloof acid is improved by almost 11 times as compared with that of the witloof acid in the raw material, thereby effectively reducing the cost. The used organic solvent and salt can be recycled, thereby effectively saving the cost.

The invention discloses a preparation method of a Fe2O3-MoS2-CdS visible photocatalysis film. The method comprises the following steps of (1) using a Fe<2+> precursor solution as an electrolyte; performing electrodeposition on a conducting substrate; then, performing roasting treatment to obtain a Fe2O3 film; (2) soaking the Fe2O3 film into a MoS2 precursor solution; preparing a Fe2O3-MoS2 film by a hydro-thermal method; (3) putting the Fe2O3-MoS2 film into the Cd<2+> precursor solution; performing heating reaction to obtain the Fe2O3-MoS2-CdS visible photocatalysis film. The invention also provides the Fe2O3-MoS2-CdS visible photocatalysis film prepared by the method, and application of the film to treatment of phenol-containing wastewater. The preparation process is simple; the repeatability is high; in addition, the economic cost is lower. Through the combination of three photocatalysts with different energy belt structures, the synergic effect is achieved; the photocatalyst performance is greatly improved.

The invention is applicable to the technical field of materials, and provides a PEF heat shrinkable film. The PEF heat shrinkable film comprises an outer film layer, a middle film layer and an inner film layer, wherein each of the outer film layer and the inner film layer is prepared from, by weight, 40-55 parts of high-pressure low-density polyethylene, 15-25 parts of high-density polyethylene, 10-15 parts of an ethylene-vinyl acetate copolymer, 5-10 parts of polyurethane acrylate, 5-10 parts of modified argil, 4-6 parts of oleamide and 2-5 parts of an antioxidant; and the middle film layer is prepared from, by weight, 25-35 parts of high-pressure low-density polyethylene, 20-30 parts of high-density polyethylene, 10-15 parts of the ethylene-vinyl acetate copolymer, 2-6 parts of modifiedgas silicon, 4-6 parts of oleamide and 1-3 parts of the antioxidant. The PEF heat shrinkable film formed by compounding the raw materials which are nontoxic and wide in source is stable in appearance,has good physical and mechanical properties such as the heat shrinkage rate, the tensile property and the tearing strength, is suitable for package and transportation of articles including but not limited to foods, electronic products and the like, and has good development prospects.

The invention discloses a method for preparing L-menthol intermediate d-citronellal. The method comprises the following steps of: (1) enabling geranyl amine (2) to react in a solvent A in the existence of a chiral catalyst, and then collecting myrcene amine (3) from a reaction product; and (2) carrying out acidic hydrolysis on the myrcene amine (3) to obtain d-citronellal (4). The structure of the chiral catalyst is as follows: [Rh(PS-Binap)2]<+>Y<->. The method has the characteristics of being mild in reaction condition, simple in operation, high in stereoselectivity, high in yield, simple in catalyst recovery and the like, and can be applied mechanically in cycle.

The invention discloses a preparation method of 3, 5-dimethyl-4-chlorophenol, which comprises the following steps: by using 3, 5-dimethylphenol as a raw material, carrying out low-temperature homogeneous chlorination reaction on 3, 5-dimethylphenol and a chlorinating agent in a solvent at 10-70 DEG C for 2-4 hours according to the molar ratio of the chlorinating agent to 3, 5-dimethylphenol of 1.05-1.1: 1, wherein the chlorinating agent is sulfuric chloride; and after the reaction is finished, rectifying the reaction product to obtain the 3, 5-dimethyl-4-chlorophenol. According to the method,the use of a high-toxicity organic solvent is avoided, and the conversion rate of a primary reaction substrate is improved.

The invention discloses a membrane separation concentrated-brine utilization technology, and in particular relates to a method for separating high-salt-containing concentrated water by a light-assisted catalytic membrane for decoloration and improving salt quality. The method adopts a fixed-bed catalyst, a plurality of oxidants are added, a processing membrane is used to separate the high-salt-containing concentrated water under light source excitation conditions, organic matter with a larger molecular structure is catalyzed the oxidized, and organic matter with a smaller molecular structure and no color or weak coloring ability is generated, so that chromaticity of the brine is reduced, and a part of COD is removed; and a mother liquor produced after the brine is separated is treated by adopting an enhancing catalytic system, so that quality of produced salt and stability of an evaporation system are improved, and zero emission is realized. The method provided by the invention has theadvantages that no new impurity oxidant is introduced, the problem of difficulty in catalyst recovery does not exist, the chromaticity of the obtained salt and the stability of the evaporation systemare ensured, and wastewater recycling and zero emission are truly realized.

The invention discloses a method for immobilizing a cellulose crosslinking crystal on a silica gel plate, and belongs to the field of enzyme engineering. The method for immobilizing the cellulose crosslinking crystal on the silica gel plate comprises the following steps: soaking the silicon gel plate with water, cleaning and drying; uniformly mixing a cellulose solution with a precipitating agent, and placing the pretreated silicon gel plate in a mixture solution to ensure that cellulose is absorbed on the silicon gel plate; adding a crosslinking agent to crosslink to form the cellulose crosslinking crystal and immobilizing the cellulose crosslinking crystal on the silicon gel plate. According to the method, the cellulose crosslinking crystal is immobilized on the silicon gel plate, so that the activity and stability of the cellulose are improved, the cellulose can be recycled without being recovered, and the utilization efficiency of the cellulose is greatly increased.

The invention discloses an intelligent integrated self-floating acoustic release mechanism. The mechanism comprises a floating body, a rope bin and an acoustic releaser, the floating body is located above the rope bin, and the acoustic releaser penetrates through the floating body and the rope bin and is fixed to the floating body; the bottom of the rope bin is fixed to underwater equipment, a rope is placed in the rope bin, one end of the rope is fixed to the bottom of the floating body, and the other end penetrates through a through hole in the bottom of the rope bin and is fixedly connected with the underwater equipment; and the acoustic releaser comprises an acoustic transducer, a control circuit and a releasing module, the acoustic transducer is located at the top of the floating body, and the releasing module is located at the bottom of the rope bin and connected with underwater equipment. According to the acoustic release mechanism disclosed by the invention, the safety and reliability of release can be improved, smooth recovery of the underwater equipment is ensured, and the influence of vibration caused by water flow impact on acoustic equipment is reduced.

The invention discloses a catalyst for preparing an L-menthol intermediate d-citronellal and a preparation method thereof. The catalyst is characterized in that the structure is [Rh(PS-Binap)2]<+>Y<->, wherein Y<-> is ClO4<->, PF6<-> or BF4<->; and Bingap is (-)-2,2'-bis-(diphenylphosphine)-1,1'-binaphthyl. The catalyst has very excellent physicochemical properties. When the catalyst is subjected to asymmetric hydrogen migration, myrcene amine can be basically obtained by utilizing a quantitative method, and nearly optically-pure d-citronellal can be obtained by carrying out simple acidic hydrolysis on the myrcene amine. The d-citronellal obtained by utilizing the method does not need to be purified and can be subjected to cyclization and high-pressure hydrogenation to produce a target product L-menthol.

The invention discloses an extraction method of lithium in spodumene, and an adsorption material for extraction of lithium and a preparation method thereof, belonging to the technical field of lithiumresource extraction. The adsorption material disclosed by the invention is a 4-aminodibenzo-14-crown-4 crown ether derivative loaded on the surface of SiO2. According to the method for extracting lithium from spodumene in the invention, a sulfuric acid method is adopted for extraction; spodumene is subjected to roasting transformation-sulfated roasting-leaching to obtain a lithium sulfate solution; then the adsorption material is adopted for adsorption treatment of the obtained lithium sulfate solution; finally, the adsorption material is washed and desorbed, a pure sodium carbonate solutionis added, heating is performed for lithium precipitation, and washing and drying are carried out to obtain a lithium carbonate product. The adsorption material disclosed by the invention has strong capacity in selective adsorption of lithium, can be effectively used for extracting lithium from spodumene via the sulfuric acid method, is high in extraction efficiency, realizes a high enrichment effect on lithium ions, and overcomes the defects of an existing sulfuric acid method extraction process.

The invention relates to a preparation method of a catalyst for DEC synthesis. The preparation method of the catalyst for DEC synthesis comprises the steps as follows: ash produced by catalytic coal gasification and haloid acid react; a solution obtained after the reaction is filtered, and a halide salt solution containing alkali metal is obtained; the halide salt solution and fly ash containing the catalyst are mixed and dried, and catalyst particles for DEC synthesis are obtained. Besides, the invention also discloses a preparation device and an application method of the catalyst for DEC synthesis as well as a system for DEC synthesis by use of the catalyst prepared with the preparation method of the catalyst for DEC synthesis. The technical route of poly-generation of the existing catalytic gasification process is realized, a chemical product with high added value is produced while a methane product is obtained, the risk that single product is limited by market supply and demand isreduced, and the overall technical economy of the process is improved.

The invention provides a preparation method of the thermoplastic carbon fiber composite material for medical instruments. The carbon fiber composite material takes a high-performance special carbon fiber as a reinforcing body, a high-performance thermoplastic resin matrix is taken as an adhesive, the high-performance thermoplastic resin matrix is subjected to melt compression molding to prepare the medical instrument, so that the problems that the traditional carbon fiber reinforced thermosetting resin composite material is difficult to recover, impact resistance and wear resistance in the useof medical instruments are effectively overcome, the defects of poor moisture resistance, heat aging resistance and high temperature resistance are overcome, the problem that the traditional medicalinstrument is difficult to form twice once forming is solved, and the medical instrument has good popularization and application values.

The invention belongs to the field of a plant protection unmanned aerial vehicle, and particularly relates to a plant protection unmanned aerial vehicle battery intelligent charging system. The plantprotection unmanned aerial vehicle battery intelligent charging system comprises a self-judgment module, an energy-saving module, a self-cleaning module, a temperature control module, a medicine blending module and a protection module; the self-judgment module is used for judging a flight route of the unmanned aerial vehicle and carrying out control on an electric quantity of a battery; the energy-saving module is used for saving power consumption of the unmanned aerial vehicle according to the flight route made in the self-judgment module by utilizing an AI intelligent risk-management technology; the self-cleaning module is used for blowing wind to a camera of the unmanned aerial vehicle by using an air hole so as to achieve a self-cleaning function; and the temperature control module isused for carrying out control on a battery temperature in the unmanned aerial vehicle in a point-to-point monitoring mode according to data acquired by the energy-saving module. The plant protection unmanned aerial vehicle battery intelligent charging system is mainly used for solving problems that an existing unmanned aerial vehicle cannot fully automatically work, battery loss is serious, and the existing unmanned aerial vehicle cannot utilize natural energy to save electric energy.