33results about How to "Good crystal form" patented technology

The invention discloses application of a mineralized carbon sequestration strain, the mineralized carbon sequestration strain is classified and named as Halomonas sulfidaeresis. ZN2 #, the mineralized carbon sequestration strain is preserved in the China General Microbiological Culture Collection Center (CGMCC), and the preservation number is CGMCC No.32033. The invention further discloses a preparation method of the mineralized carbon sequestration strain. The mineralization carbon sequestration strain can metabolize to generate urease and carbonic anhydrase at the same time, the two enzymes are subjected to a dual mineralization reaction in combination with a microorganism-induced calcium carbonate precipitation technology, the crystal form of a mineralization product is improved, the mineralization strength is improved, meanwhile, carbonic anhydrase can absorb carbon dioxide in the environment, high-strength soil reinforcement is achieved, meanwhile, carbon dioxide emission is reduced, and the soil quality is improved. Therefore, the dual effects of biomineralization remediation and improvement and carbon sequestration and emission reduction of the soil are achieved, and sustainable development of a soil bioremediation and improvement technology is achieved.

The invention relates to the field of chemical application, and discloses a device for preparing large-particle ammonium sulfate crystals through reduced-speed crystallization. Comprising a neutralization reactor, a settling separation tank, a pre-crystallization solution tank, a first-stage intermittent jacket crystallizer, a second-stage intermittent jacket crystallizer, a filter powder sieving device, an ammoximation tert-butyl alcohol tower reboiler, a heat exchanger group, a stirrer group and a centrifugal pump group, wherein the centrifugal pump group consists of a centrifugal pump I, a centrifugal pump II, a centrifugal pump III, a centrifugal pump IV and a centrifugal pump V; the invention further discloses a process for preparing the large-particle ammonium sulfate crystals through speed-reducing crystallization. The process comprises the following steps: adding rearrangement liquid from a caprolactam rearrangement system and gas ammonia into the neutralization reactor through an external circulation pipeline. By fully utilizing heat in a neutralization reaction and crystallization process and combining with a compound additive, a seed crystal and a speed reduction crystallization technology, an efficient two-stage series crystallization mode is realized, the generation of large-particle ammonium sulfate crystals is promoted, the crystal quality is optimized, the energy consumption is reduced and the production efficiency is improved.

The invention relates to the technical field of calcium carbonate manufacturing, in particular to a preparation method of high-whiteness light calcium carbonate. Comprising the following steps: efficiently leaching the calcium element in the carbide slag; preparing a microbial crystal form control agent; and carrying out electric dispersion treatment and precipitation on calcium ions. The microbial crystal form control agent is prepared by regulating and controlling the mixing ratio of the bacillus pumilus fermentation liquor to the pseudomonas fluorescens fermentation liquor, and it is avoided that in the full mixing process of the microbial crystal form control agent and the calcium-containing filtrate, Ca < 2 + > is mineralized to form large calcium carbonate particles; stearic acid and sodium polyacrylate in the microbial crystal form control agent can enable particles to be more stable, provide ion adsorption capacity, optimize the crystal form of calcium carbonate and form vaterite type crystals with smaller crystal form, and bacillus pumilus can assist generation of small-particle-size calcium carbonate along with time, so that high-whiteness small-particle-size light calcium carbonate is obtained.

The application provides a preparation method of black phosphorus arsenic material, comprising the following steps: mixing gray arsenic, red phosphorus and an additive, and then placing the mixture in a high-temperature area to react in a closed container in a protective atmosphere or vacuum, and synchronously depositing in a low-temperature area to crystallize, so as to obtain black phosphorus arsenic material; wherein the additive comprises tellurium iodide; the temperature of the high-temperature area is not lower than 550 DEG C, and the temperature of the low-temperature area is 450-530 DEG C; and the black phosphorus arsenic material is black phosphorus arsenic single crystal. The application realizes controllable synthesis of flaky black phosphorus arsenic single crystal, and has excellent applicability in semiconductor devices.

The invention belongs to the technical field of psicose preparation, and particularly relates to a method for extracting psicose crystals from psicose fermentation broth, which comprises the following steps of: performing ceramic membrane filtration and nanofiltration on the psicose fermentation broth, concentrating a nanofiltration filtered phase, performing activated carbon decoloration, performing chromatographic desalination decoloration by using a sodium chromatographic column, and performing freeze-drying to obtain the psicose crystals. And collecting the slow component for cation and anion exchange, concentrating the obtained ion exchange liquid, performing chromatographic purification by using a calcium type chromatographic column, collecting the rear-end AD liquid, and evaporating and concentrating the AD liquid. Cooling to room temperature, adding psicose ground powder as a seed crystal, adding ethanol while stirring to separate out crystals to obtain a solid-liquid mixture, and centrifuging the solid-liquid mixture to obtain psicose crystals. By adopting the method disclosed by the invention, the crystalline psicose can be extracted from the psicose fermentation liquor in a high-efficiency and energy-saving manner, and the psicose with better crystal form and higher purity and yield is obtained.

The invention discloses a waxy film manufacturing device. The waxy film manufacturing device comprises a wax dipping area, a leveling area and a film forming area which are connected from bottom to top, wherein the wax dipping area is used for containing liquid-phase paraffin; a first heat insulation plate is arranged between the wax dipping area and the leveling area; a second heat insulation plate is arranged between the leveling area and the film forming area; a third heat insulation plate is arranged above the film forming area; the temperature of the wax dipping area, the leveling area and the film forming area is controlled independently; the temperature of the wax dipping area is 5-15 DEG C higher than the melting point of the liquid paraffin, the temperature of the leveling area is 5-10 DEG C higher than the temperature of the wax dipping area, and the temperature of the film forming area is 20-30 DEG C lower than the melting point of the liquid paraffin. According to the method, wax film manufacturing is divided into the three stages of wax dipping, leveling and film forming, the temperature of a wax dipping area, the temperature of a leveling area and the temperature of a film forming area are independently controlled, the mold lifting speed is increased to 1 mm / s or above from 0.1-1 mm / s of a traditional dip-coating technology, the technology control is more convenient and faster, and therefore the covering uniformity, the thickness accuracy and the roughness of a formed film are improved, and the precision requirement of precise injection molding is met.

The invention relates to a preparation method of battery-grade sodium fluoride. The preparation method specifically comprises the following steps: (1) dissolving, filtering and removing impurities; (2) synthesis reaction; and (3) filtering, washing and drying. According to the method provided by the invention, the requirement on the purity of the raw material is relatively low, the low-price light sodium carbonate is used as the raw material, the content of the prepared sodium fluoride reaches 99.9% or above, the yield can reach 94% or above, the total content of metal impurities is less than 20 ppm, the water content is less than 100 ppm, and impurity ions such as calcium, iron, magnesium and potassium all meet the quality requirement of battery-grade sodium fluoride.

The invention provides a Tl-series superconducting thin film and a preparation method thereof, and belongs to the field of superconducting thin film materials. The preparation method of the Tl-series superconducting thin film provided by the invention comprises the following steps: mixing nitrate or acetate of metal, ethylenediaminetetraacetic acid, a water-soluble high-molecular polymer and water to obtain precursor sol; the metals are thallium, barium, calcium and copper; the molar ratio of thallium to barium to calcium to copper to ethylenediamine tetraacetic acid is (2-3): 2: 1: 2: (7-8); coating a substrate with the precursor sol to obtain a precursor film; and carrying out heat treatment on the precursor thin film in an oxygen atmosphere under a closed condition to obtain the Tl-series superconducting thin film. The Tl-series superconducting thin film obtained by the preparation method provided by the invention presents a Tl-2212 phase, no impurity phase is generated, and the critical transition temperature can reach 100K and is close to the Tl-2212 theoretical superconducting transition temperature.

The invention belongs to the technical field of food grease, and particularly relates to a method for preparing stearic acid through solvent-method fractionation of shea butter crude oil and the obtained stearic acid, and the method comprises the following steps: a gum separation step S1, fully stirring and mixing shea butter crude oil in a molten state and with saponin removed with an organic solvent, and separating to obtain a pectin phase and an oil phase; and S2, cooling the oil phase to crystallize, and carrying out filter pressing to obtain a stearic acid solid phase and an oleic acid liquid phase. And S3, removing the solvent, namely evaporating and removing the organic solvent in the pectin phase, the stearic acid solid phase and the oleic acid liquid phase to respectively obtain pectin, stearic acid and oleic acid. According to the method, the shea butter crude oil is fractionated by adopting the organic solvent, so that the flowability of the shea butter crude oil is greatly enhanced, the crystallization process is convenient to control, and the time for fractionating stearic acid, namely solid fat in the later period is greatly shortened.

A negative electrode material, a negative electrode sheet and a preparation method thereof for an aqueous magnesium ion battery belong to the field of new energy technology. The negative electrode material for the aqueous magnesium ion battery of the present invention is manganese vanadium oxide. Mn and multivalent V can both change valence in electrochemical reactions, and can provide a large number of electrons for reactions, thereby increasing the specific capacity. And the potential is suitable, and it can be used as a negative electrode material for an aqueous magnesium ion battery.

The invention discloses a construction method and application of an ectoine-producing genetically engineered bacterium, and belongs to the field of biosynthesis. Escherichia coli BL21 is used as an original strain, lacI genes of the Escherichia coli BL21 are knocked out, an expression system regulated and controlled by tryptophan is constructed, and synthesis of a product ectoine can be regulated and controlled under the condition that an inducer is not added. According to the invention, a phosphotransferase system of Escherichia coli BL21 is modified, and a glucose readifier protein coding gene Zmglf is integrated at a ptsG gene locus, so that the inhibition effect of carbon catabolism is relieved, and the cost of a culture medium is reduced. Through overexpression of a phosphoenolpyruvate carboxylase coding gene ppc and an aspartate semialdehyde dehydrogenase coding gene asd, the accumulation of precursor substances oxaloacetic acid and L-aspartate-beta-semialdehyde in the growth and metabolism process is enhanced, and the synthesis level of the product ectoine is improved.

The invention discloses an InSb quantum dot and a preparation method thereof, and the preparation method comprises the following steps: dispersing indium nanocrystals and antimony nanocrystals in an organic solvent, uniformly mixing, heating to 60-300 DEG C in the presence of a ligand, and reacting for 0.1-120 minutes to obtain the InSb quantum dot. The invention also provides an application of the InSb quantum dot in preparation of a colloidal quantum dot infrared detector, a solar cell or a luminescent device. The indium antimonide quantum dot is prepared by taking the antimony nanocrystal and the indium nanocrystal as precursors, the preparation method of the antimony nanocrystal and the indium nanocrystal is simple, the required initial raw materials are cheap and easy to obtain, and the preparation cost of the indium antimonide quantum dot is reduced.

The utility model relates to crystallization equipment technical field, concretely relates to a kind of ectoine production crystallization tank, including tank body. Concentrated liquid feed inlet and ethanol adding port are set on the tank body, ethanol feed inlet is connected with the spraying device in tank body, jacket is set on the outside of tank body, the jacket includes upper jacket and lower jacket, the volume of upper jacket and lower jacket is consistent, the upper side of the upper side of upper jacket is medium inlet, the lower side of the other side is medium outlet, the lower side of the lower side of lower jacket is medium inlet, the upper side of the other side is medium outlet, flow monitoring instrument and control valve are installed on the water inlet pipeline of jacket, temperature monitoring instrument is installed on the water outlet pipeline of jacket. The utility model can realize the uniform addition of ethanol on the one hand, and can realize the more stable control to the temperature in tank body on the other hand, so as to help ectoine better crystallization, help to ensure better crystal form and purity, positively affect product quality.

The invention relates to a refining process of probenecid, which is characterized in that a two-step refining process of acidification crystallization separation and mixed solvent crystallization purification is adopted, a crude probenecid product is put into an alkaline solution to be dissolved, activated carbon wetted by purified water is added, heat preservation and decoloration are performed for 30-40 minutes, and feed liquid is pressed into a crystallization kettle through a filter. Slowly dropwise adding an acetic acid aqueous solution, centrifugally filtering, and collecting a wet product; adding the wet product into a mixed solvent, heating and dissolving, adding activated carbon, refluxing and decoloring for 30-40 minutes, pressing the feed liquid into a crystallization kettle through a filter, starting low-speed stirring, slowly reducing the temperature in the crystallization kettle, and standing for crystallization. And carrying out spin-filtration on the filtrate, collecting a wet competitive product, and carrying out drying treatment to prepare a competitive probenecid product. According to the probenecid refining process disclosed by the invention, the process parameters are easy to control, the solvent ratio is reduced, and the batch yield is greatly increased; the refined probenecid is a white body, the appearance property and quality are greatly improved, the HPLC purity is greater than or equal to 99.9%, and the single impurity is less than or equal to 0.10%.

The invention discloses a triazole iron-based spin cross complex, which has the following chemical expression: [FeL2]X2; the invention also discloses a method for preparing the triazole iron-based spin cross complex: step 1, synthesizing ligand L by 2-cyano-6-(1-pyrazole)pyridine or 6-cyano-2,2'-bipyridine and hydrazide; step 2, reacting ligand L with ferrous salt in acetonitrile to obtain a reaction solution; step 3, placing the reaction solution in a closed container with ether and standing to precipitate crystals. The complex of the invention has a clear crystal structure and variable temperature magnetic susceptibility data, and the ligand field of the spin center can be adjusted by adjusting the terminal coordination point of the ligand L, and then the spin state of Fe(II) can be adjusted; by changing the substituent and counter anion on the ligand L to adjust the spin cross property of the complex, it has potential application value in the technical fields of high-density information storage and molecular switch devices.

The invention discloses a method for removing arsenic from arsenic-containing industrial gypsum and simultaneously preparing alpha calcium sulfate hemihydrate. The method specifically comprises the following steps: drying, crushing and sieving the arsenic-containing industrial gypsum; the method comprises the following steps: mixing arsenic-containing industrial gypsum powder with a sulfuric acid solution with the mass concentration of 5-7% to obtain gypsum suspension slurry, adding the gypsum suspension slurry into a reaction kettle, carrying out stirring reaction at 110-150 DEG C for 60-180 minutes, cooling to 100 DEG C, carrying out suction filtration on the slurry while the slurry is hot, sequentially washing with boiling water and absolute ethyl alcohol for 2-4 times respectively, and drying to obtain the alpha calcium sulfate hemihydrate. According to the method, deep removal of arsenic in the arsenic gypsum can be realized, and the removal rate of arsenic is gt; according to the method disclosed by the invention, the product obtained under the condition that no crystal modifier is added has a relatively good crystal form and a relatively small length-diameter ratio, and the method disclosed by the invention realizes arsenic removal of the arsenic-containing industrial gypsum and preparation of a gypsum product with a high additional value.

This invention discloses a photochromic material incorporating a HOF (Hormone-Organic-Flatform) framework, its preparation method, and its applications. Belonging to the field of organic solid-state photochromic materials technology, it utilizes a host-guest eutectic method to load photochromic molecules onto the HOF framework material. This invention also discloses the photochromic material prepared by the above method, and its applications in information storage encryption and anti-counterfeiting. While achieving photochromism, the host-guest eutectic method exhibits a faster photoresponse rate and better photochromic performance compared to physical adsorption methods, showing greater potential in anti-counterfeiting and excellent information storage encryption capabilities.

The present invention discloses a C / C composite cathode plate, a combined electrode, a preparation method and an application. The preparation method of the C / C composite cathode plate is to mix raw materials including graphite powder, phenolic resin and carbon fiber, and then add carbon nanotube slurry to obtain a mixture; evaporate the solvent from the mixture, add the mixture into a mold for hot pressing to obtain a green body; place the green body in a carbonization furnace for carbonization treatment. The cathode plate has low resistance, high strength, low density, good electrical properties, can be used stably for a long time, and it is not easy to introduce impurities when it is used. The combined electrode formed by the cathode plate and the TiMn alloy anode plate has the advantages of good electrochemical performance, strong stability, long service life, etc., and is used to prepare electrolytic MnO 2 When the electrolytic MnO 2 The cell voltage can reduce energy consumption, can adapt to high acidity and high current density environments, and can effectively regulate MnO 2 Crystal form and purity.

The invention discloses a medical ultra-transparent propylene-butadiene binary co-polypropylene material as well as a preparation method and application thereof, and belongs to the field of high polymer materials. The invention provides a medical ultra-transparent propylene-butadiene binary co-polypropylene material, which is prepared from the following raw materials in parts by weight: 75 to 85 parts of propylene; 15 to 25 parts of butylene; 0.1 to 0.5 part of a medical transparent nucleating agent; 0.1 to 0.5 part of an antioxidant; and 0.2 to 0.8 part of a biological compatilizer. The haze of the medical ultra-transparent propylene-butadiene binary co-polypropylene material provided by the invention can be as low as 5% or below, the light transmittance is as high as 98% or above, and the medical ultra-transparent propylene-butadiene binary co-polypropylene material has ultra-high transparency so as to accord with the harsh standard of the medical field on the transparency of the material, and has irreplaceable important significance in the aspects of visual operation of medical instruments and the like.

The application relates to the technical field of nanometer material preparation, in particular to a manganese antimonate nanometer material and a preparation method thereof. A manganese salt solution, an antimony salt solution and a complexing agent solution are mixed, and then pH is adjusted to obtain a precursor solution; the precursor solution is mixed with a soft film edition agent, and then stirring and heating are carried out to form a sol, and the sol is subjected to standing and drying to obtain a dry gel; the dry gel is subjected to one-stage heat treatment in an air or oxygen atmosphere, and then cooling and grinding are carried out after the one-stage heat treatment, and then two-stage heat treatment is carried out after the grinding to obtain the manganese antimonate nanometer material. The manganese antimonate nanometer material with high purity and high performance is prepared by controlling solution chemistry, gelation conditions and heat treatment parameters. The product has high purity, good crystal form, simple preparation mode, high operability and high repeatability. The product is suitable for the fields of magnetic materials, catalysts, battery materials and the like, and has wide industrial application prospects.

This invention discloses a multi-layer gradient fluidized bed coupled with ultrasound-enhanced calcium fluoride crystallization device, comprising a reaction tower and a cyclone separator connected to the reaction tower. The reaction tower includes a bottom sludge discharge zone, a bottom reaction zone, a middle reaction zone, and a top reaction zone arranged sequentially from bottom to top. The bottom reaction zone includes a bottom reaction shell; a bottom sieve plate is provided at the top of the bottom reaction shell, and a bottom ultrasonic transducer is provided at the top of the bottom reaction shell; a wastewater tangential injection pipe and a calcium solution injection pipe are provided at the bottom of the bottom reaction shell. The middle reaction zone includes a middle reaction shell, and a middle ultrasonic transducer is provided at the top of the middle reaction zone. The top reaction zone includes a top reaction shell, and a top ultrasonic transducer is provided at the top of the top reaction shell. This invention not only improves the layered crystal growth rate but also increases the resource recovery rate.

The invention discloses a novel method for crystallizing thiamine nitrate, which comprises the following steps of: adding ammonium nitrate prepared by mixing industrial-grade stronger ammonia water and concentrated nitric acid according to the volume ratio of 1: 1 into 15-20 percent by mass of thiamine thiooxide liquid, and regulating the temperature to 15-45 DEG C; and adjusting the pH value with ammonia water not higher than 25%, adding a seed crystal when the pH value is 4.0-5.0 until the final pH value is 5-8, stirring and crystallizing for 0.5-2 hours at the speed of 100-600r / min, and then filtering and drying. Preferably, the concentration of ammonia water is 5%, the temperature is 15-35 DEG C, and the rotating speed is 300-400 r According to the method, parameters are accurately regulated and controlled, the length-diameter ratio of thiamine nitrate is reduced to 1.8-2.1, the yield is increased to 93-95% from 87%, the flowability is greatly optimized, the problems that existing products are fine in grain and prone to electrostatic adsorption are solved, the process is simple, the cost is low, and the method is suitable for industrial production.

An efficient impurity removal device for dissolved slurry comprises a settling tank, a crude liquid tank and a leaf filter, a feeding port of the settling tank is used for being connected with a dissolved slurry source, an overflow pipe is arranged on the upper portion of the side wall of the settling tank to supply materials to the crude liquid tank, a discharging port of the crude liquid tank supplies materials to the leaf filter through a conveying pump, and a feeding mechanism is arranged on the overflow pipe. The feeding mechanism comprises a liquid inlet pipe which is bent and extends in a snake shape, the upstream end of the liquid inlet pipe is connected with the liquid preparation tank, the downstream end of the liquid inlet pipe is communicated with the overflow pipe, and the liquid preparation tank is provided with a first inlet used for being connected with a lime milk source and a second inlet used for being connected with a filter aid source. The device is simple in structure and low in improvement cost, and can reduce the use amount of lime milk on the basis of ensuring that impurities in the dissolved slurry are removed.

The invention discloses a triazole iron-based spin crossover complex. The triazole iron-based spin crossover complex has the following chemical expression formula: [FeL2] X2, the invention also discloses a preparation method of the triazole iron-based spin crossover complex, which comprises the following steps: step 1, synthesizing a ligand L from 2-cyano-6-(1-pyrazole) pyridine or 6-cyano-2, 2 '-bipyridine and hydrazide; 2, reacting the ligand L with ferrite in acetonitrile to obtain a reaction solution; and 3, placing the reaction liquid in a closed container with diethyl ether, standing, and separating out crystals. The complex disclosed by the invention has a clear crystal structure and variable temperature magnetic susceptibility data, and a ligand field of a spin center can be adjusted by adjusting a coordination site at an L end position of a ligand, so that the spin state of Fe (II) can be adjusted; the spin crossover property of the complex is adjusted by changing substituent groups and counter anions on the ligand L. The complex has potential application value in the technical field of high-density information storage and molecular switch devices.

This invention belongs to the field of methoxyamine hydrochloride preparation technology and discloses a method for separating methoxyamine hydrochloride and ammonium chloride. The method involves cooling a mixed solution containing ammonium chloride and methoxyamine hydrochloride to selectively crystallize out ammonium chloride, which is then separated to obtain ammonium chloride crystals and a mother liquor enriched with methoxyamine hydrochloride. The mother liquor is then concentrated or dissolved by heating, followed by ultra-low temperature crystallization, separation, and drying to obtain methoxyamine hydrochloride crystals. This invention uses ultra-low temperature segmented crystallization to selectively precipitate ammonium chloride, resulting in methoxyamine hydrochloride crystals with a purity ≥99.9% and ammonium chloride crystals with a purity ≥98%.

This invention relates to the field of wastewater treatment technology, and more particularly to a method for enhancing anaerobic ammonia oxidation (AAO) denitrification using iron-loaded polyurethane porous materials. The method includes the following steps: Anaerobic ammonia oxidation sludge, iron-loaded polyurethane porous materials, and wastewater containing ammonia nitrogen and nitrite nitrogen are thoroughly mixed in an anaerobic reactor and reacted under anaerobic conditions at a temperature of 31-35°C. The iron-loaded polyurethane porous materials are prepared as follows: polyurethane sponge is selected as a carrier, cut and cleaned, and then immersed and stirred in a mixed iron salt solution for a period of time. The pH of the mixed solution is adjusted to alkaline, resulting in the formation of a red precipitate. The iron-loaded polyurethane porous materials are then hydrothermally synthesized. The mixed iron salt solution includes ferric chloride and ferric nitrate. The carrier material prepared by this invention, when applied to an anaerobic ammonia oxidation system, can effectively shorten the process start-up time, promote the enrichment and biofilm formation of anaerobic ammonia oxidizing bacteria, and achieve a high total nitrogen removal rate.

The present application relates to a kind of resourceful treatment method of ammonium chloride crystallization mother liquor dry salt, belong to the waste residue processing technical field of ion type rare earth hydrometallurgy field.The present application uses adsorption technology and chemical precipitation method, step by step separates pollutants from waste residue, produces calcium sulfate, calcium carbonate, the crystalline precipitate of ammonium magnesium phosphate, carries out solid-liquid separation, and then converts evaporation salt into high-purity ammonium chloride solution.The present application is suitable for the treatment of ammonium chloride crystallization mother liquor dry salt with different proportions of various components, according to the solubility product constant of sulfide precipitation, calcium sulfate, calcium carbonate, ammonium magnesium phosphate is very small, step-by-step precipitation method is used to separate impurity elements in salt, strictly control process parameters, realize the transformation of ammonium chloride crystallization mother liquor dry salt to high-purity ammonium chloride solution, the existing precipitation and adsorption material in step is easy to solid-liquid separation, process technology is simple, easy to operate control, chemical reagent consumption is less, and salt treatment cost is low.

The invention belongs to the technical field of nano materials, and discloses a CeO2 loaded NiCo-LDH nano catalyst and a preparation method thereof. The preparation method comprises the following steps: dispersing a doping source cerium salt, a nickel salt and a cobalt salt in a reaction solvent to obtain a metal salt solution; uniformly dispersing a precipitant urea in the metal salt solution to obtain a mixed solution; the mixed solution is subjected to a reflux reaction at 85-95 DEG C, so that nickel ions and cobalt ions provided by the nickel salt and the cobalt salt are subjected to a precipitation reaction with urea to form NiCo-LDH, cerium salt is converted into CeO2 on the surface of NiCo-LDH in a nano-particle form, and the CeO2-loaded NiCo-LDH nano-catalyst is obtained. The preparation method disclosed by the invention is low in reaction temperature, short in reaction time and simple and can be used for large-scale production; the prepared catalyst has excellent electronic conductivity and excellent electro-catalytic performance, and is beneficial to popularization and large-scale production and use.

The invention relates to a method for one-step in-situ preparation of a Z-type NiMn2O4 / NiO composite photocatalyst with a compact interface and application of the Z-type NiMn2O4 / NiO composite photocatalyst. The preparation method comprises the following steps: firstly, respectively dispersing MnCl2. 4H2O and Ni (NO3) 2.6 H2O in distilled water according to a certain molar ratio, adding a proper amount of NaOH solution into the distilled water, fully stirring to precipitate, and collecting; and uniformly mixing the collected precipitate, filtering, washing, drying, grinding and calcining to form the NiMn2O4 / NiO composite photocatalyst. According to the preparation method, the Z-type NiMn2O4 / NiO composite photocatalyst is prepared in situ through a simple one step, a tight interface is formed between NiMn2O4 and NiO through in-situ construction, and electron transfer of a system is facilitated. The method for preparing the composite photocatalyst is simple and convenient, the effective Z-type obtaining rate is high, the catalyst crystal form structure is good, and organic pollutants in water can be efficiently photocatalytically degraded under sunlight.