7149 results about "Sodium hydroxide" patented technology

A fireproof magnesium oxide board is prepared by mixing the following raw materials, the raw material names and weight parts are as follows: 80-100 parts of magnesium oxide; 20-30 parts of anhydrous magnesium chloride; 10-20 parts of modified expanded vermiculite foaming agent; 20-30 parts of aluminum silicate fiber; 5-10 parts of sawdust; 10-15 parts of fly ash; 8-12 parts of glass magnesium board crushed powder; 1.5-5 parts of non-woven fabric; 10-20 parts of water; wherein the modified expanded vermiculite is prepared by the following steps: (1) Vermiculite is incompletely expanded and calcined; (2) acrylic acid monomer, sodium hydroxide, acrylamide monomer, initiator potassium persulfate, crosslinking aid pentaerythritol polyglycidyl ether, incompletely expanded vermiculite, and water are taken, stirred evenly and ultrasonically dispersed to obtain a first reaction solution, which is placed in a reactor for reaction to obtain a gel material; (3) the gel material is preliminarily crushed and dried, and then further crushed in a ball mill to obtain a fire-resistant expanded vermiculite with water absorption performance.

The invention discloses a method for activating and precipitating MHP through magnesium, and belongs to the technical field of hydrometallurgy. The method comprises the following steps: S1, mixing a magnesium-containing solution with a sodium hydroxide solution, and carrying out precipitation reaction for 3-5 minutes to obtain a precipitator; s2, immediately mixing a precipitator with the laterite-nickel ore iron and aluminum removed liquid, and then carrying out first-stage nickel and cobalt precipitation reaction to obtain first-stage nickel and cobalt precipitation slurry; s3, performing first thickening treatment on the first-section nickel and cobalt deposited slurry to obtain first dense underflow and first dense overflow; and S4, filtering the first dense underflow to obtain an MHP product. According to the method, after the magnesium-containing solution and the sodium hydroxide solution are mixed, the magnesium solution and the sodium hydroxide solution are controlled to be mixed and react for 3-5 min, then the nickel and cobalt precipitation reaction is immediately carried out, the MHP product with high purity and quality can be obtained, and the whole method is simple and convenient for large-scale industrial application.

The invention relates to the field of solidified soil, and particularly discloses solid-waste-based premixed flow-state solidified soil and a preparation method thereof. The solid-waste-based premixed flow-state solidified soil comprises soil, water and a curing agent according to the weight ratio of (28-36): (50-54): (6-9), according to the total weight of the curing agent, the curing agent comprises the following components in parts by weight: 20-40 parts of fly ash, 30-47 parts of slag, 6-18 parts of silica fume, 10-15 parts of sea sludge, 1-3 parts of a water reducing agent, 1-3 parts of sodium hydroxide, 1-3 parts of calcium sulphoaluminate, 3-10 parts of a fiber reinforced material and 1-3 parts of phosphate. The problems that stress generated by the solidified soil in the hydration process is excessively concentrated and shrinkage is excessive can be solved, and therefore cracking of the solidified soil subjected to premixed flow state solidification is reduced.

The present invention relates to the field of biomedicine technology, specifically a preparation method of a silk fibroin hyaluronic acid filler for injection. The present invention concentrates a silk fibroin solution to obtain a concentrated silk fibroin solution, and then dilutes it to obtain a diluted silk fibroin solution; the diluted silk fibroin solution is heated to form a silk fibroin gel, granulated to obtain silk fibroin gel particles; 1,4-butanediol diglycidyl ether and a sodium hydroxide solution are mixed uniformly, hyaluronic acid and 1 / 3 of the mass fraction of hydroxyapatite are added, after stirring uniformly, swelling, purification and granulation are carried out, and the remaining mass fraction of hydroxyapatite is added to obtain composite gel particles; the composite gel particles and the silk fibroin gel particles are mixed uniformly, added to the gel to mix, and a silk fibroin hyaluronic acid filler is obtained, which effectively prolongs its degradation time.

The invention discloses a method for preparing a composite positive electrode material by using a waste battery, and belongs to the technical field of battery recovery. The method comprises the following steps: discharging, disassembling and sorting a waste lithium iron phosphate battery to obtain a positive plate, carrying out water treatment, separating from an aluminum foil to obtain a waste lithium iron phosphate sheet, adding sodium hypochlorite, tetraethoxysilane, deionized water and hydrochloric acid, stirring to obtain SiO2-coated iron phosphate precipitate particles and a lithium-containing solution, adding sodium hydroxide into the lithium-containing solution to adjust the pH value, and carrying out solid-liquid separation to obtain the lithium-ion battery cathode material. Adding sodium carbonate, heating and drying to obtain lithium carbonate precipitate. And adding a carbon source and alcohol into the SiO2-coated iron phosphate precipitate particles and lithium carbonate, carrying out ball milling, taking out, drying, and calcining in a protective atmosphere to obtain the positive electrode composite material. Compared with the prior art, according to the prepared positive electrode composite material, material particles contain a lithium silicate network, so that the specific discharge capacity of a battery material is effectively improved. The method is simple in process and suitable for comprehensive utilization of waste batteries.

The invention provides a preparation method of a polyester loose nanofiltration membrane, and belongs to the technical field of nanofiltration membrane preparation. The preparation method provided by the invention comprises the following steps: dissolving a water-phase monomer in a sodium hydroxide solution to obtain a NaOH solution containing the water-phase monomer; soaking an ultrafiltration membrane in the NaOH solution containing the aqueous phase monomer to obtain an ultrafiltration membrane supporting layer; contacting the ultrafiltration membrane supporting layer with a trimesoyl chloride solution, and carrying out interfacial polymerization reaction to obtain a primary nanofiltration membrane; and carrying out heat treatment on the primary nanofiltration membrane to obtain the polyester loose nanofiltration membrane. The water-phase monomer is a compound which has a non-planar distorted structure and simultaneously contains phenolic hydroxyl groups and alcoholic hydroxyl groups. The method provided by the invention is simple and easy to implement, relatively low in required cost and beneficial to realizing large-scale industrial production of the high-efficiency nanofiltration membrane. The polyester loose nanofiltration membrane prepared by the preparation method disclosed by the invention has relatively high permeation flux, and meanwhile, a relatively high Na2SO4 retention rate can be kept.

The invention discloses an external field reinforced molybdenum concentrate impurity removal method, and belongs to the technical field of molybdenum concentrate impurity removal. The method comprises the following steps: (1) microwave enhanced chloridizing roasting: uniformly mixing the molybdenum concentrate and calcium chloride, and carrying out microwave heating roasting in an inert atmosphere protection environment to obtain a roasted product; (2) ultrasonic enhanced acid leaching: adding the roasted material obtained in the step (1) into a hydrochloric acid solution, leaching under an ultrasonic condition, and then sequentially carrying out suction filtration, washing and drying to obtain an acid leached material; and (3) ultrasonic enhanced alkaline leaching is conducted, specifically, the acid leaching material obtained in the step (2) is added into a sodium hydroxide solution, leaching is conducted under the ultrasonic condition, then suction filtration, washing and drying are conducted in sequence, and iron and silicon removal of the molybdenum concentrate is completed. By means of the method, the iron and silicon removal effect of the molybdenum concentrate can be effectively improved, and the iron and silicon removal rate can reach 97% or above.

The invention relates to a comprehensive utilization method of fluosilicic acid containing hydrogen fluoride, which comprises the following steps: 1) reacting a stock solution containing fluosilicic acid with a potassium fluoride raw material, and carrying out solid-liquid separation to obtain potassium fluosilicate and a hydrofluoric acid solution; 2) reacting potassium fluosilicate with a sodium hydroxide raw material, and carrying out solid-liquid separation to obtain a mixture of a potassium fluoride solution, sodium fluoride and silicon dioxide; and returning the potassium fluoride solution to the step 1) to be recycled as a potassium fluoride raw material. According to the scheme, hydrofluoric acid is prepared from fluosilicic acid containing hydrogen fluoride, sodium fluoride and water glass products are produced at the same time, no other byproduct waste is produced, and the raw material utilization rate is high. And meanwhile, the method has the advantages of low raw material cost, low equipment cost and low energy consumption cost, can generate remarkable economic benefits, and is suitable for popularization and application.

The invention provides an MHP precipitation method based on a compound alkali precipitator and application of the MHP precipitation method, and the MHP precipitation method comprises the following steps: mixing laterite-nickel ore iron and aluminum removed liquid and a compound alkali solution for precipitation reaction to obtain cobalt nickel hydroxide slurry; the compound alkali in the compound alkali solution comprises a mixture of sodium carbonate and sodium hydroxide; and carrying out post-treatment on the cobalt nickel hydroxide slurry, and separating to obtain the MHP. According to the method, a sodium hydroxide and sodium carbonate compounded system is used as a precipitator, the MHP is prepared under the cooperation of sodium carbonate and sodium hydroxide, the content of manganese in the obtained MHP is remarkably reduced, the content of nickel and cobalt in the MHP is increased, the method has important significance for reducing the cost for preparing crystals through subsequent MHP refining, meanwhile, the reaction rate is more controllable, the obtained MHP is better in filtering performance, and the method is suitable for industrial production. The water content is lower.

The invention discloses a CoFeCuMn LDH nanosheet, a confinement catalytic membrane and a preparation method of the CoFeCuMn LDH nanosheet. The preparation method of the CoFeCuMn LDH nanosheet comprises the steps that A1, cobalt salt, ferric salt, copper salt and manganese salt are dissolved in pure water according to a preset proportion to prepare a first solution, sodium hydroxide is dissolved in pure water to prepare a second solution, and sodium carbonate is dissolved in pure water to prepare a third solution; a2, adding the first solution and the second solution into the third solution, and stirring to obtain a mixed solution; a3, carrying out hydrothermal reaction on the mixed solution; a4, centrifugally washing the product obtained in the step A3 to obtain a precipitate; and A5, the sediment is dried, and the CoFeCuMn LDH nanosheet is obtained. According to the CoFeCuMn LDH nanosheet, the confinement catalytic membrane and the preparation methods of the CoFeCuMn LDH nanosheet and the confinement catalytic membrane, the degradation efficiency and the degradation rate of new pollutants are remarkably improved.

The invention provides a preparation method of an acid-resistant and chlorine-corrosion-resistant porous composite electrode and a device constructed on the basis of the electrode and used for preparing hydrogen and chlorine by electrolyzing a sodium chloride solution, two cavities are provided, an acid or neutral saturated sodium chloride solution is filled in the cavities, the cavities are separated by a proton exchange membrane or a diaphragm, and the proton exchange membrane or the diaphragm is filled in the cavities. And in the electrolysis process, the cathode generates high-purity hydrogen, the anode generates high-purity chlorine, the chlorine is absorbed by sodium hydroxide in the gas collection bottle and generates sodium hypochlorite, or the chlorine is introduced into a sodium bromide / sodium iodide solution to replace bromine / iodine elementary substances, and the chlorine is discharged from the gas collection bottle. The sodium hypochlorite solution and the bromine / iodine water are used for disinfection and sterilization experiments. The corrosion-resistant porous composite electrode for electrolysis of an acidic or neutral saturated sodium chloride solution is prepared, the electrolysis voltage of the corrosion-resistant porous composite electrode is further reduced by loading a cathode / anode catalyst, and an acidic or neutral saturated sodium chloride solution electrolysis device constructed based on the electrode can be used for preparing high-purity hydrogen and chlorine.

The invention provides a method for efficiently synthesizing basic nickel carbonate, and belongs to the technical field of chemical preparation. Comprising the following steps: (1) preparing a mixed solution of sodium carbonate and sodium hydroxide; (2) under low-temperature and high-speed stirring conditions, dropwise adding a nickel salt solution into the mixed solution, adding a competitive adsorbent, adjusting the pH value of the solution, then heating, continuing stirring reaction, separating the competitive adsorbent by a magnet, centrifuging, washing and collecting prepared primary basic nickel carbonate; and (3) recrystallizing the primary basic nickel carbonate in an ethanol water solution, and drying to obtain the basic nickel carbonate. According to the preparation method disclosed by the invention, the content of impurity ions in the product is reduced, so that the high-purity basic nickel carbonate can be prepared, the synthesis efficiency is high, the production cost is relatively low, the method is green and environment-friendly, the competitive adsorbent can also be repeatedly utilized and recycled, the production cost is reduced, and the method has a wide application prospect.

According to the invention, biomass rice hull ash and a sodium hydroxide solution are reacted to obtain water glass and carbon mud. And reacting the water glass with CO2 generated by calcining the limestone to produce a white carbon black product and a mixed waste liquid of sodium carbonate and sodium bicarbonate. Meanwhile, quick lime obtained by calcining limestone is digested and then reacts with sodium carbonate and sodium bicarbonate mixed waste liquid to generate a light calcium carbonate product and dilute sodium hydroxide waste liquid. And finally, the dilute sodium hydroxide waste liquid is concentrated and reused for water glass production, so that the waste liquid is recycled, and a complete process closed loop is formed. According to the process method disclosed by the invention, two leading-edge innovative processes, namely production of white carbon black by renewable resource biomass rice hull ash and production of white carbon black by a carbonization method, are organically combined and are coupled with production of light calcium carbonate by a limestone calcination process, so that the problem that a large amount of sodium sulfate-containing wastewater is discharged in a traditional process is solved; meanwhile, the carbon footprint of white carbon black and calcium carbonate products is greatly reduced.

Disclosed in the present invention are a fluorosilicone-modified low-surface-energy antifouling coating and a preparation method therefor. The coating comprises the following components in parts by weight: 11-15 parts of butyl acrylate, 3-4 parts of dodecafluoroheptyl methacrylate, 3-4 parts of vinyl-terminated polydimethylsiloxane, 3-4 parts of 2-hydroxy-4-acryloyloxybenzophenone, 30-38 parts of methyl isobutyl ketone, 0.15-0.25 parts of azobisisobutyronitrile, 0.1-0.2 parts of sodium hydroxide, 2-3 parts of modified titanium dioxide nanoparticles, and 0.5-1.5 parts of 3-aminopropyltriethoxysilane. In the present invention, vinylpentamethyldisiloxane reacts with decamethylcyclopentasiloxane to prepare vinyl-terminated polydimethylsiloxane; a titanium dioxide precursor is mixed with polydopamine nanoparticles for modification to prepare modified titanium dioxide nanoparticles; and then the components above are mixed to prepare the fluorosilicone-modified low-surface-energy antifouling coating. The coating has low surface energy and good adhesion and ultraviolet resistance.

The invention discloses a mixed gas-imitating gel fiber as well as a preparation method and application thereof, and belongs to the technical field of fiber materials. The mixed gas-imitating gel fiber is prepared from the following components: cellulose dispersion liquid, a silane coupling agent and viscose in a mass ratio of (1-3): (0.2-0.8): (5-10), comprising the following steps: adding sodium hydroxide into a cellulose dispersion liquid, adjusting the pH value to be alkaline, adding viscose and a silane coupling agent, and carrying out ultrasonic stirring to prepare a mixed spinning solution; the mixed spinning solution is extruded into a coagulating bath through a wet spinning device to be drafted, wet fibers are obtained, and the mixed gas-imitating gel fibers are obtained after freeze drying. The aerogel fiber disclosed by the invention has low heat conductivity coefficient, high mechanical strength and extreme temperature resistance, can solve the problem that the densification and porosity of a traditional fiber structure are difficult to balance, and effectively expands the application prospect of the aerogel fiber in the fields of cold protection, warm keeping and the like.

The invention relates to a preparation method and application of a Janus structure photo-thermal-piezoelectric hydrogel dressing for infected wound repair, and the preparation method comprises the following steps: respectively dissolving phenylboronic acid grafted methacrylamide gelatin and dopamine grafted hyaluronic acid in deionized water, adding MXene coated CeO2 heterojunction, and ultrasonically dispersing uniformly, so as to obtain the Janus structure photo-thermal-piezoelectric hydrogel dressing for infected wound repair. After mixing, sodium hydroxide is used for adjusting the pH value to alkalescence, and a Janus structure inner layer is formed; respectively dissolving phenylboronic acid grafted gelatin and o-nitrobenzyl alcohol grafted hyaluronic acid in deionized water, adding BaTiO3, ultrasonically dispersing uniformly, and mixing to form a Janus structure outer layer; the Janus structure photo-thermal-piezoelectric hydrogel dressing prepared by the invention has the characteristic of space-time release so as to adapt to the wound repair process, in addition, the Janus structure photo-thermal-piezoelectric hydrogel dressing also has excellent photo-thermal conversion performance, bacteria infecting the wound are killed through photo-thermal heating, physiological electric signals are effectively simulated through the piezoelectric effect, cell behaviors are regulated and controlled, and the Janus structure photo-thermal-piezoelectric hydrogel dressing can be used for wound infection repair.

The invention discloses a method for recovering lithium phosphate from lithium iron phosphate black powder. The method comprises the following steps: mixing black powder recovered from waste lithium iron phosphate batteries with sodium persulfate, and calcining; adding water into the obtained calcined product, dissolving, filtering to obtain water extract A and leaching residues, washing the leaching residues with water, and calcining at high temperature to obtain battery-grade iron phosphate; adding a sodium hydroxide solution into the water extract A, and reacting to obtain a water extract B; adding a trisodium phosphate solution into the water immersion liquid B, fully reacting, performing suction filtration to obtain lithium phosphate and filtrate, and cleaning and drying the lithium phosphate to obtain battery-grade lithium phosphate; and freezing and denitrifying the filtrate to obtain a denitrified solution, and adding the denitrified solution into the sodium hydroxide solution for recycling. The method does not generate wastes, recycles the filtrate in the whole process, theoretically realizes zero loss of the lithium element, prevents the iron element from entering the solution, simplifies the preparation steps of the lithium phosphate, and has the advantages of cost reduction and environmental protection.

The invention discloses a high-temperature-resistant power tube and a production process thereof, and belongs to the technical field of power tube preparation. The high-temperature-resistant electric power tube is prepared from, by weight, 60-80 parts of a high-temperature-resistant base material, 10-30 parts of carbon fibers and 1-5 parts of a modified anti-aging agent, the high-temperature-resistant base material is prepared from 2, 3, 4-trifluorobenzaldehyde, malonic acid, oxynaphthalene propionic acid, trifluoroacetic anhydride and 2, 2-bis [4-(4-aminophenoxy) phenyl] propane, and the modified anti-aging agent is prepared from 2, 3, 4-trifluorobenzaldehyde, malonic acid, oxynaphthalene propionic acid, trifluoroacetic anhydride and 2, 2-bis [4-(4-aminophenoxy) phenyl] propane. The modified anti-aging agent is prepared from absolute ethyl alcohol, paeonol, sodium hydroxide and 2-methoxybenzaldehyde. The power tube prepared by the method has excellent high temperature resistance, mechanical property and aging resistance.

The invention discloses a preparation method of a fly ash-Al-MOF material loaded with sodium percarbonate and acid-containing ferrous sulfate, which comprises the following steps: carrying out heat treatment on fly ash, cooling, adding into a sulfuric acid solution, stirring and mixing, carrying out solid-liquid separation, adding sodium hydroxide into a liquid product to adjust the pH value to 4.5-6 to obtain an aluminum hydroxide precipitate, washing and roasting to obtain aluminum oxide, and drying to obtain the fly ash-Al-MOF material loaded with sodium percarbonate and acid-containing ferrous sulfate. The preparation method comprises the following steps: mixing fly ash-Al-MOF with a sulfuric acid solution to obtain an aluminum sulfate solution, uniformly mixing the aluminum sulfate solution with a phthalic acid solution, carrying out solid-liquid separation, washing a solid product, carrying out freeze drying to obtain fly ash-Al-MOF, and respectively loading sodium percarbonate and acid-containing ferrous sulfate on the fly ash-Al-MOF to obtain fly ash-Al-MOF loaded with sodium percarbonate and fly ash-Al-MOF loaded with acid-containing ferrous sulfate; and uniformly mixing the two components to obtain a finished product. Compared with the existing method, the material prepared by the invention can realize long-term, stable, effective and environment-friendly remediation of the organic polluted soil, and the remediation efficiency is high.

The preparation method comprises the following steps: mixing agar, carrageenan and a gelatin solution to prepare a core material hydrogel; mixing sodium hydroxide, water glass and water to prepare an intermediate binder A; mixing the regenerated micro powder with biochar to prepare an intermediate binder B; mixing the binder A and the binder B to obtain an intermediate binder; mixing the regenerated micro powder and the granulated blast furnace slag powder to obtain an outer core material; putting hydrogel into the binder A and the binder B, wrapping the surface of the hydrogel with a mixed binder solution, putting the hydrogel into the binder B, obtaining a material C, and drying and curing the material C to obtain a hollow core; and granulating the hollow core, spraying the binder A while pouring the shell powder to form a spherical aggregate, and rolling the spherical aggregate at a rotating speed to obtain the unfired hollow artificial aggregate. According to the preparation method disclosed by the invention, the unfired hollow artificial aggregate with relatively low bulk density and relatively high single-particle compressive strength is prepared by taking the regenerated micro powder and the slag solid waste material as a shell and the hydrogel as an inner core in an alkali excitation manner.

The invention relates to the technical field of precious metal recovery, in particular to a precious metal recovery method which comprises the following steps: I, crushing a waste catalyst, blending the waste catalyst with sodium carbonate according to the weight ratio of 1: (0.5-1.2), and roasting at 700-1000 DEG C for 0.5-3 hours to obtain a roasted product; and II, dispersing the roasted product and sodium hydroxide in the weight ratio of (0.2-0.5): 1 in water at the temperature of 50-90 DEG C, stirring at the rotating speed of 80-320 r / min for 5-20 min for leaching, filtering while hot after leaching is finished, and collecting, washing and drying filter residues to obtain the recovered noble metal. According to the recycling method, the precious metal is efficiently recycled from the high-carbon-content catalyst by accurately controlling parameters of all the steps, and compared with a traditional recycling method, the recycling rate is remarkably increased, the influence on the environment is reduced, and meanwhile the production cost is reduced.

The invention provides a continuous purification method of crude acetonitrile, and belongs to the field of acetonitrile purification. The continuous purification method of the crude acetonitrile comprises the following steps: rectification light component removal, membrane separation impurity removal, adsorption impurity removal and rectification purification. According to the continuous purification method of the crude acetonitrile, continuous purification of the crude acetonitrile can be realized, and meanwhile, the problems that new impurities are introduced by side reactions, the rectification efficiency and the rectification stability are influenced by treated products and the device is influenced by over-high alkalinity of the treated secondary rectification liquid due to the fact that sodium hydroxide and formaldehyde are adopted to treat the rectification liquid are avoided; the acetonitrile product with the purity meeting the requirement is prepared by continuously purifying the crude acetonitrile.

The invention discloses a method for selectively recycling phosphorus pollutants in low-concentration phosphorus-containing sewage and preparing high-quality blue iron ore and application, and belongs to the technical field of water treatment and recycling thereof. According to the method, the low-concentration phosphorus-containing sewage is adsorbed by a phosphorus specific nano adsorption material HFO-201, and then the material is desorbed by adopting sodium hydroxide and sodium chloride with specific concentrations. The desorbed filtering material and the filtered material can be repeatedly used for adsorbing phosphorus in low-concentration sewage. After the pH value of the filtered desorption solution is adjusted to a certain concentration, FeCl2 with a certain concentration is added, and high-quality blue iron ore (Fe3 (PO4) 2.8 H2O) can be generated by keeping the pH value through sodium hydroxide under an anaerobic condition. The phosphorus product recovered by the process can be used for preparing a high-value phosphate fertilizer and a high-energy-density energy storage material, namely lithium iron phosphate (LiFePO4). The HFO-201 used in the invention can realize low-concentration phosphorus adsorption through an ammonium group combined with a D-201 matrix and loaded HFO nanoparticles. And moreover, after alkali desorption, the damage to the material is very low, and the material can be repeatedly used. And finally, the process of producing the high-quality blue iron ore through phosphorus recovery of the desorption solution is simple and easy to operate. Through XRD, ICP and other detection, it is found that the phosphorus recovery product is determined to be the blue iron ore, and the purity is very high. Through economic analysis and life cycle evaluation, it can be found that the method has remarkable economical efficiency, and the influence on the environment in the production process is small.

The invention belongs to the field of coal gangue resource utilization, and particularly discloses a method for preparing fiber-reinforced coal gangue-based composite functional aerogel. After being activated, the coal gangue is put into an acid leaching solution to be leached, and an aluminum-rich solution is obtained; adding ammonia water into the aluminum-rich solution to adjust the pH to obtain hydroxide precipitate; adding a sodium hydroxide solution into the precipitate to react to obtain a sodium aluminate solution; neutralizing the sodium aluminate solution with hydrochloric acid to obtain an aluminum chloride solution, stirring to obtain aluminum sol, and adding ceramic fibers into the aluminum sol; violently stirring the sol, and adding epoxypropane to obtain wet gel; after aging the wet gel, carrying out surface modification to obtain hydrophobic coal gangue-based aluminum oxide and composite wet gel of the hydrophobic coal gangue-based aluminum oxide; and drying the modified wet gel at normal pressure to obtain the hydrophobic coal gangue-based aluminum oxide and the composite aerogel thereof. Ceramic fibers are introduced as a reinforcing phase, so that the compressive strength and toughness of the material are improved; the composite aerogel is subjected to surface modification, uniform modification is ensured, the contact angle is remarkably increased, the hygroscopicity is reduced, and the stability of the material is enhanced.

The invention relates to hybrid fiber reinforced ultrahigh-performance geopolymer concrete as well as a preparation method and application thereof. Slag, metakaolin and silica fume are used as precursor materials of geopolymer concrete, a sodium hydroxide-water glass solution is adopted to compound an alkali activator, and steel fibers, polyvinyl alcohol fibers and modified glass chopped fibers of different sizes are mixed and doped, so that the brittleness of the geopolymer concrete is remarkably improved, and the service life of the geopolymer concrete is prolonged. The early strength and the high temperature resistance are improved. The hybrid fiber reinforced ultrahigh-performance geopolymer concrete has the characteristics of low carbon emission, ultrahigh strength, high temperature resistance, high durability and the like, and can meet the use of the geopolymer concrete in actual engineering. According to the ultrahigh-performance geopolymer concrete, solid waste resources are utilized at the same time, carbon emission in the concrete production process is reduced, and the ultrahigh-performance geopolymer concrete is environmentally friendly, low in carbon, ultrahigh in strength, easy to prepare and capable of being suitable for complex environmental engineering structures such as tunnels, bridges and high-rise buildings.

The invention provides steam-cured alkali-activated fly ash concrete and a preparation method thereof. The steam-cured alkali-activated fly ash concrete is prepared from the following components in parts by mass: 30 to 40 parts of fly ash, 10 to 15 parts of slag, 10 to 20 parts of water glass, 60 to 80 parts of fine aggregate, 110 to 140 parts of coarse aggregate, 2 to 6 parts of water, 1 to 3 parts of nano SiO2 and 0.1 to 0.5 part of basalt fiber. The content of alkali in the water glass is 8.5-9.5%, and the modulus of the water glass is adjusted to 1.3-1.5 by using sodium hydroxide; the mass ratio of short fibers with the length of 6-12mm to long fibers with the length of 12-24mm in the basalt fibers is (0.5-2): 1. The alkali content, the water glass modulus and steam curing parameters are optimized, and meanwhile, nano SiO2 and basalt fibers are added for synergistic enhancement, so that the concrete has good crack resistance and compressive strength.

The invention discloses a preparation method and application of a metal nitrogen-carbon loaded high-load platinum catalyst, and belongs to the field of four-electron oxygen reduction. The method comprises the following steps: firstly, dispersing a synthesized metal carrier in ethylene glycol, carrying out uniform ultrasonic treatment, dropwise adding a chloroplatinic acid solution, continuously carrying out uniform ultrasonic dispersion, dropwise adding sodium hydroxide until the pH value is 11, and stirring for 2 hours; reacting the reaction liquid in an oil bath at 125 DEG C for 3 hours, cooling to room temperature, adding hydrochloric acid to settle the reaction liquid, washing with a large amount of water, and drying in vacuum to obtain the target catalyst. According to the synthesis method, relatively environment-friendly solvents such as methanol and ethylene glycol are used, so that the pollution to the environment is reduced, the used raw materials are relatively cheap, the energy consumption in the preparation process is relatively low, and the production cost of the catalyst is favorably reduced. The prepared catalyst shows excellent oxygen reduction performance and has a good industrial prospect.

The utility model belongs to the field of chemical raw material recovery, and discloses a continuous resourceful treatment system for photovoltaic fluorine-containing wastewater. The system comprises a first-stage fluorine removal unit, a second-stage fluorine removal unit and a silicon removal unit. According to the utility model, the fluorine element is subjected to resource recovery in the form of high-purity calcium fluoride with the purity of more than 95%, meanwhile, the consumption of a fresh sodium hydroxide solution is avoided, the purpose of treating waste with waste is realized, and the residual fluorine quantity in the effluent of the system is reduced to be less than 5mg / L.

The invention provides a method for preparing a lithium slag-based molecular sieve by melting lithium slag with assistance of eutectic salt, and relates to the technical field of molecular sieves. The method comprises the following steps: carrying out acid pickling pretreatment on a lithium slag raw material to obtain pretreated lithium slag; co-grinding and uniformly mixing the pretreated lithium slag and eutectic salt, and reacting at 200-350 DEG C for 2-6 hours to obtain eutectic lithium slag; carrying out aging treatment and crystallization treatment on the eutectic lithium slag, carrying out solid-liquid separation, washing the solid to be neutral, and drying to obtain a lithium slag-based molecular sieve; wherein the eutectic salt comprises an alkali solvent and an auxiliary salt, the alkali solvent is sodium hydroxide, and the auxiliary salt is at least one of chlorine salt, villiaumite, carbonate, sulfate and nitrate; the molar ratio of the alkali flux to the auxiliary salt is (4-19): 1. According to the method, the eutectic salt system is introduced in the lithium slag alkali fusion stage, meanwhile, the molar ratio of the alkali flux to the auxiliary salt in the eutectic salt is controlled to be (4-19): 1, the alkali fusion reaction temperature is reduced, the reaction of the lithium slag and alkali is promoted, the molecular sieve yield is increased, the product morphology can be regulated and controlled, and a specific molecular sieve can be formed in a guiding mode.

The invention belongs to the technical field of desiliconized fly ash, and particularly relates to a high-alumina-silica-ratio material capable of replacing bauxite as well as a preparation method and application of the high-alumina-silica-ratio material. The preparation method comprises the following steps: S1, crushing coal gangue, and grinding the crushed coal gangue until the particle size is less than 40 meshes to obtain a ground material; s2, mixing the ground material and a catalyst according to a weight ratio of 100: (1-2), roasting, and cooling to obtain activated coal gangue; the catalyst comprises sodium carbonate, calcium oxide and aluminum oxide in a weight ratio of 1: (0.3-0.5): (1.4-1.6); s3, mixing a sodium hydroxide solution, the activated coal gangue and a surfactant, and reacting at 50-90 DEG C for 1-6 hours to obtain desiliconized slurry; and S4, filtering the desiliconized slurry, collecting a solid phase, washing with water, and drying to obtain desiliconized fly ash, namely the high alumina-silica ratio material capable of replacing bauxite. The method is high in desiliconization rate.