59 results about "Cerous chloride" patented technology

The invention discloses a method for preparing nano cerium oxide through supergravity reinforcement, which comprises the following steps: 1) completely dissolving cerium chloride hexahydrate serving as a cerium source with deionized water to prepare a cerium chloride solution; (2) inputting the cerium chloride solution into a supergravity reactor through a peristaltic pump at normal temperature, then inputting ammonia water into the supergravity reactor through a constant-flux pump, and carrying out premixing reaction in the supergravity reactor to form mixed slurry; and 3) after the premixing reaction is finished, taking out the mixed slurry, and carrying out suction filtration, washing, drying and high-temperature oxidation calcination to obtain the nano cerium oxide. According to the method, the production efficiency can be improved, the particle size of the prepared nano cerium oxide is small, the particle size distribution is narrowed, and the crystallinity of crystals is improved.

The invention relates to a composite multi-effect scale and corrosion inhibitor and a preparation method thereof, and belongs to the technical field of water treatment agents.The composite multi-effect scale and corrosion inhibitor is prepared from carboxylic acid monomers, sulfonate monomers, organophosphorus compounds, modified chitosan, modified nanometer titania, oxidation type initiators, reduction type initiators, azole derivatives and the like, the modified chitosan is formed by coating the surface of chitosan with cerium chloride; the modified nano titanium dioxide is formed by coating the surface of nano titanium dioxide with sodium polyaspartate. The composite multi-effect scale and corrosion inhibitor is prepared in a mode of compounding while synthesizing, the scale inhibition effect is excellent, the comprehensive descaling capacity can reach 97% or above, and the composite multi-effect scale and corrosion inhibitor can be used for a high-pH, high-alkalinity, high-temperature and high-hardness circulating cooling water system under the high-concentration-multiple operation condition; the method is suitable for circulating cooling water treatment requirements under harsh conditions in industries such as chemical industry, smelting and light industry.

The invention belongs to the technical field of pyridone ethanolamine salt synthesis, and discloses an environment-friendly pyridone ethanolamine salt preparation process which comprises the following preparation steps: enabling isononanoyl chloride and 3, 3-methyl dimethacrylate to react under the catalysis of a solid acid catalyst to prepare 3, 7, 9, 9-tetramethyl-2-decene-5-keto acid methyl ester, and enabling the 3, 7, 9, 9-tetramethyl-2-decene-5-keto acid methyl ester to react under the catalysis of a solid acid catalyst to prepare 3, 7, 9, 9-tetramethyl-2-decene-5-keto acid methyl ester. The preparation method of the solid acid catalyst comprises the following steps: S1, taking water as a solvent, adding 14-16 parts by weight of zirconium oxychloride, 1-3 parts by weight of titanium sulfate, 0.1-0.5 part by weight of chloroplatinic acid and 0.05-0.4 part by weight of cerium chloride, adjusting the pH value to 10-11, and aging to obtain a precipitate; s2, roasting the precipitate obtained in the step S1 in an air atmosphere at 500-600 DEG C to obtain a solid acid catalyst; the method has the advantages that the catalyst is easy to recycle, and the reusability is high.

The invention provides a rare earth heat insulation coating and a preparation method thereof. The coating comprises the following components in parts by weight: 50-60 parts of acrylic resin, 10-15 parts of polyurethane modified epoxy resin, 5-8 parts of nano rare earth powder, 3-5 parts of filler, 0.5-1 part of a coalescing agent, 1-2 parts of a defoaming agent, 1-3 parts of a dispersing agent, 0.5-1 part of an ultraviolet light absorber and 1-2 parts of a silane coupling agent. Wherein the nano rare earth powder comprises lanthanum oxide powder, cerium chloride powder and yttrium hexaboride powder, and the filler comprises nano hollow microspheres, nano calcium carbonate and nano aluminum silicate. The rare earth heat insulation coating has excellent heat insulation effect and mechanical property, and can be applied to various scenes.

The invention provides an inorganic mineral fiber based on water-quenched slag and a preparation method thereof, and belongs to the field of inorganic mineral fiber materials. Titanium oxide powder is synthesized through tetrabutyl titanate and compounded with lanthanum oxide, the high temperature resistance and corrosion resistance of the fiber are improved through the synergistic effect, and the thermal stability and structural integrity of the lanthanum oxide-titanium oxide composite powder are improved through calcination treatment. Meanwhile, the dispersity and the interface bonding force of the powder are optimized through plasma treatment and silane coupling agent modification, so that the mechanical property and the heat resistance of the fiber are enhanced. In addition, phosphate and zirconium oxide are introduced to coat zinc oxide, so that the zinc oxide shows better fluidity and dispersity in a high-temperature melting process; the fiber surface is treated through magnesium chloride and cerium chloride, so that the corrosion resistance and high-temperature stability are improved; the microwave heating technology improves the surface treatment efficiency, avoids the thermal degradation problem of a traditional method, and ensures the long-term stability and performance of the fiber in a severe environment.

The invention relates to the technical field of hemostatic materials, in particular to a kaolin hemostatic material with an anti-inflammatory function and a preparation method and application thereof. The invention relates to a kaolin hemostatic material with an anti-inflammatory function. The kaolin hemostatic material comprises kaolin loaded with CeO2 nanoparticles. The preparation method comprises the following steps: mixing kaolin with cerium chloride, sodium carbonate and sodium chloride according to a certain mass ratio, then carrying out ball milling to obtain a precursor, and roasting the precursor to obtain the kaolin hemostatic material with the anti-inflammatory function. According to the preparation method, kaolinite which is low in price and rich in reserves is adopted as a raw material, a conventional CeO2 raw material is selected, a CeO2-loaded kaolinite-based nano material is prepared through a mechanochemical synthesis method, and the CeO2 / K nano material with synergistic anti-inflammatory and hemostatic activity is prepared.

The invention discloses a metal smelting additive. The smelting additive comprises cerium chloride, calcium fluoride and metal cerium, wherein the calcium fluoride accounts for 10-15%; 2-5% of metal cerium; the cerium chloride accounts for 60-70%, and the balance is the poising agent. The calcium fluoride, the metal cerium, the cerium chloride and other raw materials are blended and matched, and the balancing agent is added to balance and adjust the coordination of thermal conductivity, strength and ductility, so that the balance and improvement among performances in the conventional technology are broken; meanwhile, a functional additive of metal cerium is also added and is used for better interface bonding of cerium and the raw materials and coordination among the raw materials, so that the performance of the product is better improved.

The invention discloses polyacrylate anti-deposition and cerium chloride synergistic composite corrosion inhibitor cooling liquid, relates to the field of cooling liquid, and is particularly suitable for a multi-metal cooling system. According to the method, polyacrylate, cerium chloride, benzotriazole, benzimidazole, ethylene glycol, deionized water and triethanolamine serve as core raw materials, during preparation, equipment and the raw materials are pretreated, then a base solution is prepared, the pH value is adjusted to be alkalescent, then polyacrylate and cerium chloride are dissolved and coordinated, an auxiliary corrosion inhibitor is added, and synergistic protection is formed. And defoaming, filtering and filling. The cooling liquid adapts to multi-metal material protection through the synergistic effect of deposition resistance of polyacrylate and corrosion inhibition and synergism of cerium chloride, the cooling liquid is diluted according to working conditions during application, waste cooling liquid is discharged after being subjected to combined treatment of biological contact oxidation and Fenton oxidation, a finished product needs to be stored in a proper environment in a sealed mode, and the protection performance, the environmental protection property and the storage stability are effectively considered.

The invention discloses a catalyst for synthesizing glycollic acid and a preparation method. The catalyst comprises the following components in percentage by weight: 5-10% of copper oxide, 15-40% of manganese oxide, zirconium oxide or cerium oxide and 50-80% of modified aluminum oxide. The preparation method comprises the following steps: adding a certain amount of copper-containing compound solution into aluminum oxide powder modified by manganese chloride, zirconium chloride or cerium chloride, adding gel containing water, binder methyl cellulose and peptizing agent, uniformly kneading on a kneading machine, and extruding and molding the kneaded material on a banded extruder to obtain the copper-containing aluminum oxide composite material. And drying and roasting to obtain the catalyst for synthesizing glycollic acid. The catalyst for synthesizing glycollic acid, prepared by the invention, takes modified aluminum oxide as a main component, and has better activity and performance; the preparation process provided by the invention is relatively environment-friendly, and has a relatively good application prospect.

The invention discloses a rare earth element doping modification process of an optical module electroplated layer, which belongs to the technical field of optical module manufacturing, and comprises the following steps: sequentially carrying out oil removal, acid pickling and activation treatment on an optical module matrix to form a clean active surface; the preparation method comprises the following steps: taking nickel aminosulfonate or potassium gold cyanide as main salt, adding 0.5-5g / L of rare earth salt which is at least one of cerium chloride, lanthanum nitrate or yttrium sulfate, and adding 5-15g / L of sodium citrate complexing agent and lauryl sodium sulfate surfactant; under the conditions that the pH is 3.5-4.5 and the temperature is 45-55 DEG C, pulse current with the density being 2-5 A / dm < 2 > is adopted for electroplating, the pulse frequency is 100-500 Hz, and the duty ratio is 30-50%; when electroplating deposition is carried out, hydrogen bubbles on the outer side of the optical module are removed through a hydrogen removal device, the hydrogen bubbles are prevented from being attached to the surface of a cathode, and the uniformity of codeposition of rare earth and metal is ensured; and after electroplating is completed, deionized water cleaning and vacuum drying are carried out on the optical module. The high temperature resistance of the surface of the optical module obtained through the technology is improved.

The invention discloses cerium oxide powder, a preparation method and a chemical mechanical polishing solution. The invention provides a preparation method of cerium oxide powder, which comprises the following steps: S1, forming a mixed solution of a cerium chloride solution and an ammonium salt solution under an air condition; and S2, in an inert gas atmosphere, continuously dropwise adding an ammonium salt solution into the mixed solution, and after dropwise adding, carrying out heating reaction, filtering and drying to obtain the truncated octahedral cerium oxide powder. According to the method, cerium chloride is used as a cerium source, weak base or neutral ammonium salt is used as a precipitator, and the cerium oxide powder in a truncated octahedron shape is prepared in an inert gas atmosphere. The truncated octahedral cerium oxide powder has the advantages of uniform particle size distribution, large particle size and high product purity, and the prepared polishing solution has excellent silicon dioxide removal rate and high selection ratio of silicon dioxide to silicon nitride.

The present invention relates to the technical field of hemostatic materials, and in particular to a kaolin hemostatic material with anti-inflammatory function, and a preparation method and application thereof. The kaolin hemostatic material with anti-inflammatory function of the present invention comprises kaolin loaded with CeO2 nanoparticles. The preparation method comprises mixing kaolin with cerium chloride, sodium carbonate and sodium chloride in a certain mass ratio, ball milling the mixture and obtaining a precursor, and calcining the precursor to obtain the kaolin hemostatic material with anti-inflammatory function. The present invention adopts kaolinite, which is inexpensive and abundant in reserves, as a raw material, selects conventional CeO2 raw material, and prepares a kaolin-based nanomaterial loaded with CeO2 by a mechanochemical synthesis method, thereby preparing a CeO2 / K nanomaterial with synergistic anti-inflammatory and hemostatic activity.

The invention provides a fluidized catalytic cracking catalyst with high rare earth content, a preparation method and application of the fluidized catalytic cracking catalyst in a high-iron vanadium-nickel feed catalytic cracking process, the preparation method comprises the following steps: step 1, mixing and stirring clay, pseudo-boehmite, cerium chloride, alumina sol, silica sol and water to obtain a first mixed solution; step 2, adding a P modified USY molecular sieve, cerium chloride and a silicon-containing macroporous bauxite slurry into the first mixed solution in the step 1, pulping, homogenizing, forming, roasting, washing and drying to obtain the fluidized catalytic cracking catalyst with high rare earth content. At present, the conventional rare earth content in the industry is less than 3.5% and is not more than 5% at most, while the catalyst disclosed by the invention adopts the design of high rare earth content and low molecular sieve content, iron, vanadium and nickel are passivated by the high rare earth content, and the structural stability of the catalyst is guaranteed.

The application discloses a preparation method of a carbon-loaded CeNCl catalyst and application thereof, and belongs to the field of catalysts. The preparation method comprises the following steps: mixing cerium chloride and chitosan, and performing ball milling treatment to obtain pretreated materials; and performing calcination treatment on the pretreated materials in an N2 atmosphere, and naturally cooling after the calcination treatment is completed to obtain the carbon-loaded CeNCl catalyst. The catalyst preparation process is simple, time-consuming is short, and mass production and industrial application can be realized. The catalyst after a catalytic reaction is easy to separate and recycle. The catalyst preparation raw materials are widely sourced and cheap. The catalyst has excellent catalytic performance and can obtain a yield close to 100%.

The invention relates to the technical field of preparation of rare earth compounds, in particular to a preparation method of low-chlorine cerous carbonate. The preparation method comprises the following steps: uniformly mixing a monocarboxyl-containing substance with a cerium chloride solution, adding the mixture and an ammonium bicarbonate solution into a base solution, and reacting to obtain the low-chlorine cerium carbonate. The low-chlorine rare earth carbonate is directly prepared in a high-concentration chlorination system by adopting a simple liquid phase precipitation method; the preparation method is simple in process, stable in product quality, capable of remarkably reducing the use amount of washing water and suitable for industrial production, and is an important method for preparing the high-purity rare earth product precursor.

The present application relates to a kind of micro CO efficient removal adsorbent and its preparation and application, the preparation method includes the following steps: (1) active carbon powder, active component A, inorganic clay and dispersing agent are placed in ball mill and are uniformly ground, and mixture material is obtained;(2) active component B and the water solution of reducing agent are atomized and sprayed into the mixture material, then glue is added, and wet material is obtained;(3) wet material is extruded into shape by template, after heat reduction, after drying, calcination, CO removal adsorbent is obtained, i.e. target product;Active component A is monovalent copper salt, and active component B is the mixture of lanthanum chloride and at least one of cerium chloride or yttrium chloride.The strength and adsorption capacity of the CO removal adsorbent of the present application are increased by more than 30% and 25% respectively, the strength is ≥40N / cm, the wear is ≤1.5wt%, the CO adsorption capacity is ≥35ml / g (40℃), the removal precision can reach below 0.01ppm, suitable for the efficient purification of trace CO in hydrogen, nitrogen and other raw gas.

The invention discloses a polishing method of an optical glass lens and cerium oxide polishing powder.The polishing method comprises the working procedure of preparing a cerium oxide polishing solution and the working procedure of polishing the optical glass lens through the cerium oxide polishing solution, and the cerium oxide polishing solution is formed by dispersing the cerium oxide polishing powder in a solvent; the method for preparing the cerium oxide polishing powder comprises the following steps: at 55-65 DEG C, continuously adding a carbonate precipitator into cerium chloride rare earth feed liquid, reacting until the pH value of a system reaches 6.0-6.5 to obtain rare earth carbonate slurry, purifying, adding polyethylene glycol with proper molecular weight, stirring and aging, heating to 90 DEG C or above, and preserving heat; after the heat preservation is finished, carrying out filter pressing, drying, calcining, carrying out water cooling, and carrying out ball milling; according to the method, the cerium oxide polishing solution prepared from the specific cerium oxide polishing powder is used for polishing the optical glass lens, so that the polishing quality is excellent, the polishing efficiency is high, the safety and the environmental protection property are better, and the polishing life is long.

The application relates to a composite catalytic system for accelerating hydrogen production by magnesium hydride hydrolysis and a preparation method and application thereof, relates to the technical field of hydrogen production by magnesium hydride hydrolysis, and solves the problem that the existing hydrogen production by magnesium hydride hydrolysis reaction has large mass transfer resistance in the later stage and it is difficult to realize rapid and complete conversion of MgH2 under mild conditions. The composite catalytic system is composed of independently mechanically ball-milled pre-activated magnesium hydride powder and cerium chloride powder. In an inert atmosphere, the magnesium hydride powder is independently mechanically ball-milled for pretreatment to obtain activated magnesium hydride powder; the activated magnesium hydride powder and the cerium chloride powder are uniformly mixed according to a set molar ratio to obtain a cerium-based composite catalytic system. The above cerium-based composite catalytic system is added into water to initiate a hydrolysis reaction for hydrogen production at 20-60 DEG C. The catalytic system can stably meet the rapid gas production demand of a portable hydrogen supply device, has catalytic efficiency and cost advantages, and is suitable for large-scale application in actual scenes.

The present invention relates to a hydrosilylation-curable organopolysiloxane composition which contains an organopolysiloxane and an organohydrogenpolysiloxane crosslinked via a hydrosilylation reaction, a nonreactive organopolysiloxane resin which exhibits a mass loss rate of 2.0 mass% or less when exposed to 200°C for 1 hour, and optionally a reaction product of an alkali metal silanolate and at least one or more cerium chlorides and / or carboxylates. The composition has a low elastic modulus and low stress, and has excellent strength, cold resistance, and transparency. Furthermore, the addition of a cerium compound allows these characteristics to be maintained even under high temperature conditions for a long period of time, and provides a cured product that is resistant to cracking, peeling, and the like, particularly when a strong temperature gradient occurs inside the composition.

The invention belongs to the technical field of titanium dioxide, and particularly relates to a preparation method of special titanium dioxide for PEEK special plastics, the special titanium dioxide for PEEK special plastics is prepared through composite coating of cerium chloride and polydimethylsiloxane, and a cerium chloride modified and coated cerium oxide film layer can capture free radicals and inhibit high-temperature oxidation of PEEK; the dispersion performance of the titanium dioxide and the compatibility of the titanium dioxide and PEEK can be improved through modified coating of the polydimethylsiloxane; after a PEEK crude product is prepared by mixing and hot pressing the prepared special titanium dioxide for the PEEK special plastic and the PEEK, dopamine amide is used for surface modification, and the dopamine amide can be connected with the surfaces of the PEEK and the titanium dioxide, so that the surface defects are reduced, and the impact resistance of the PEEK special plastic is improved; the prepared PEEK special plastic has excellent antibacterial performance and impact resistance. The special titanium dioxide for the PEEK special plastic disclosed by the invention has excellent oxidation resistance, dispersibility and compatibility with PEEK.

The present invention belongs to the technical field of adhesives, and particularly relates to a sealing glue for heating tubes and a preparation process thereof. The sealing glue for heating tubes, by mass, comprises: 90-130 parts of alkoxy-terminated α,ω-dihydroxypolydimethylsiloxane, 10-20 parts of cerium chloride-doped terminal phenol group modified silicone oil, 5-15 parts of carbon hydroxyl-terminated polydimethylsiloxane, 80-120 parts of filler, 3-8 parts of crosslinking agent, 1-5 parts of catalyst, and 1-3 parts of coupling agent; the filler comprises spherical silicone resin and modified montmorillonite; the mass ratio of the spherical silicone resin to the modified montmorillonite is 1:(1-3). The sealing glue for multiple heating tubes of the present invention has good high temperature resistance, high temperature edible oil resistance, thermal cycle resistance, and damp heat resistance, and can meet the requirements of sealing glue for heating tubes of various electrical appliances.

The invention belongs to the field of organic synthesis and photocatalysis, and relates to a method for preparing a disulfide compound and producing hydrogen by catalyzing dehydrogenation of a sulfydryl compound through cerium trichloride. A sulfhydryl compound 1 is used as a raw material, cerium salt is used as a photocatalyst, and a photocatalytic reaction is carried out under the irradiation of visible light to prepare a disulfide compound 2 and hydrogen. According to the method, a visible light catalysis system is adopted, cerium trichloride is used as a catalyst, and efficient dehydrogenation coupling reaction of the sulfhydryl compound is achieved under the conditions of normal temperature and normal pressure; in the reaction, an oxidizing agent (such as peroxide or metal high-valence salt) or a free radical initiator does not need to be additionally added, only hydrogen (H2) is used as a unique byproduct in the reaction and can be recycled, the problems of toxic byproducts and metal residues generated by using a strong oxidizing agent in a traditional method are avoided, and the method conforms to the development concept of green chemistry.

The invention relates to the field of refining agent preparation, and discloses a preparation method of a refining agent for smelting an aluminum alloy profile, and the refining agent for smelting comprises magnesium carbonate, potassium carbonate, magnesium fluoride, aluminum fluoride, an additive, potassium fluosilicate and potassium fluoroaluminate. The preparation method comprises the following steps: mixing the components, drying and dehydrating, molding by a press, crushing and granulating, and performing multi-stage screening to obtain the refining agent for smelting. The additive is formed by mixing calcium nitride and modified silicon nitride according to the mass ratio of 1: (1-2); the modified silicon nitride is prepared by grafting silicon tetrachloride with cerium chloride, magnesium chloride and n-propylamine, generating silicon nitride in situ in a pyrolysis process, carrying out spark plasma sintering to obtain silicon nitride ceramic, and coating the surface of the silicon nitride ceramic with aluminum powder by taking sodium water glass as an adhesive. And impurities and oxide layers in the aluminum alloy can be effectively removed, and the quality and purity of the aluminum alloy are improved.

The invention discloses a preparation method of a zinc-cerium aerogel sensing material for detecting acetone gas, and relates to the field of aerogel sensing materials. The preparation method of the zinc-cerium aerogel sensing material for detecting acetone gas comprises the following steps: mixing anhydrous zinc chloride and anhydrous cerium chloride according to a molar ratio of 1: 2 in a solution of absolute ethyl alcohol and ultrapure water according to a ratio of 3: 1, adding citric acid according to a molar ratio of more than or equal to 1: 10 to the anhydrous zinc chloride, then adding ethylene oxide according to a molar ratio of more than or equal to 1: 2 to the anhydrous zinc chloride, and uniformly stirring to obtain the zinc-cerium aerogel sensing material for detecting acetone gas. The zinc-cerium aerogel sensing material capable of detecting the acetone is prepared by adding the zinc-cerium aerogel into a tubular furnace, drying the zinc-cerium aerogel in a 5L carbon dioxide supercritical drying device, and finally preparing the zinc-cerium aerogel sensing material capable of detecting the acetone through the tubular furnace in an air atmosphere under the conditions that the heating rate is 1-2 DEG C / min, the calcining temperature is 500 DEG C and the calcining time is 4 hours, and the prepared sensing material has the advantages of high response to the acetone, low detection limit and the like. The characteristics of high specific surface area and high porosity of the aerogel material are fully exerted.

The invention relates to the technical field of metal material corrosion resistance research, in particular to a preparation method of a rare earth conversion coating on the surface of an AZ91D magnesium alloy material. According to the preparation method, the AZ91D magnesium alloy is placed in a rare earth passivation solution to be soaked, and preparation of the rare earth conversion coating on the surface of the AZ91D magnesium alloy is completed; the rare earth passivation solution is rare earth salt, a hydrogen peroxide solution and water; the rare earth salt is one or two of cerium chloride and lanthanum chloride. Cerium chloride, lanthanum chloride or cerium chloride and lanthanum chloride are used for replacing highly toxic chromate; precise control over the thickness, density and component distribution of a film layer is achieved by improving key process parameters such as passivation temperature, time, concentration and a soaking mode, the uniformity and matrix binding force of the conversion film are remarkably improved, local corrosion weak points are avoided, the high-quality rare earth conversion film is formed, and the service life of the rare earth conversion film is prolonged. And the corrosion resistance of the AZ91D magnesium alloy is improved through the rare earth synergistic effect.

The invention relates to a cerium oxide precursor sol spinning solution and a preparation method of a cerium oxide fiber membrane. The method comprises the steps of synthesis of a cerium oxide precursor, preparation of sol, electrostatic spinning and heat treatment. Anhydrous cerium chloride and basic cerium carbonate are used as cerium sources, an oxidation-reduction reaction is innovatively adopted to promote dissolution coordination of cerium so as to synthesize a high-quality precursor, then the prepared precursor and an alcohol solvent are mixed according to a certain proportion, a trace amount of a spinning auxiliary agent is added, and the cerium oxide fiber membrane with excellent performance can be obtained through electrostatic spinning and heat treatment. The method has the advantages that the precursor synthesis process is controllable, high-quality fibers can be rapidly prepared, and industrial production and application are facilitated. The cerium oxide fiber membrane has potential application in the aspects of thermal radiation resistance, thermal insulation, photocatalysis and the like.

The invention discloses a method for preparing high-grade low-chloride large-particle crystal form cerous carbonate normal salt, which comprises the following steps: diluting rare earth in a cerium chloride solution with pure water until the rare earth concentration is 0.23-0.35 mol / L and the pH value is 2-5; preparing an ammonium bicarbonate solution by using pure water, and controlling the concentration of the ammonium bicarbonate solution to be 2.2-2.6 mol / L; adding seed crystal cerium carbonate and an ammonium bicarbonate solution into the cerium chloride solution, stirring, and carrying out carbon precipitation reaction at the reaction temperature of 50 + / -2 DEG C; and leaching the cerium carbonate slurry by using leaching water, and carrying out suction filtration to obtain the large-particle crystal form cerium carbonate. An ammonium bicarbonate precipitation method is used, additives are not needed, the large-particle-size cerium carbonate product is prepared by controlling main factors influencing precipitation, and the purpose that the particle size of the carbonate product is controllable is achieved.

This disclosure relates to a hydrosilylation-curable organopolysiloxane composition which contains an organopolysiloxane and an organohydrogenpolysiloxane crosslinked via a hydrosilylation reaction, a non-reactive organopolysiloxane resin which exhibits a mass loss rate of 2.0 mass % or less when exposed to 200° C. for 1 hour, and optionally a reaction product of an alkali metal silanolate and at least one or more cerium chlorides and / or carboxylates. The composition has a low elastic modulus and low stress, and has excellent strength, cold resistance, and transparency. Furthermore, the addition of a cerium compound allows these characteristics to be maintained even under high temperature conditions for a long period of time, and provides a cured product that is resistant to cracking, peeling, and the like, particularly when a strong temperature gradient occurs inside the composition.

The invention discloses a composite material as well as a synthesis method and application thereof. The composite material comprises cerium chloride nitrogen and carbon. The synthesis method of the composite material comprises the following steps: mixing chloromethyl resin with a first solvent, adding a nitrogen-containing organic compound for reaction, and drying to obtain modified chloromethyl resin; adding a cerium precursor and a second solvent into the modified chloromethyl resin under heating and stirring conditions, mixing, drying, and roasting in an inert gas atmosphere to obtain the composite material. The composite material disclosed by the invention can be applied to transesterification and shows good catalytic performance.

This invention relates to the field of wastewater treatment, specifically to a water treatment agent for synergistic removal of fluoride and heavy metals and its preparation method. By weight, it comprises the following raw materials: 100 parts water, 10-30 parts aluminum-based flocculant, 0.5-3 parts citric acid, 2-10 parts modified montmorillonite, 1-3 parts cerium chloride heptahydrate, 1-8 parts calcium chloride, 1-3 parts soluble zirconium salt, 2-4 parts thiolated chitosan, and 2-3 parts stabilizer. Through the synergistic effect of the aluminum-based flocculant, organic ligand, modified montmorillonite, polymetallic salt, and thiolated chitosan, it achieves efficient, deep, and simultaneous removal of fluoride ions and various heavy metal ions from wastewater, exhibiting high removal efficiency and good stability.