591results about How to "Low reaction conditions" patented technology

The invention discloses a method for efficiently and cleanly recovering platinum group metals from a spent automobile catalyst, which comprises the following steps: (1) smelting and collection: mixing the spent automobile exhaust catalyst with a collector, a reducer and a slag former, and carrying out high-temperature smelting to obtain a collected metal-platinum group metal alloy; (2) alloy phase oxidation and converting: blowing oxidizing gas into the collected metal-platinum group metal alloy to perform converting; (3) high-grade platinum group metal enrichment dissolution and separation: carrying out oxidizing solvent dissolution and ion-exchange separation to obtain a platinum group metal solution, adding alkali into the exchange raffinate to neutralize and precipitate, and returning the precipitate as the collector for the smelting step; and (4) platinum group metal refinement: refining and purifying the platinum group metal solution to obtain the platinum group metal product. The method efficiently recovers the platinum group metals; the recovery rate of the platinum group metals is greater than 99%, and the platinum+palladium+rhodium content in the smelting slag is less than 10g / t; and the collector can be recycled, so that the method is clean and pollution-free and can easily implement industrialization.

The invention belongs to the technology field of nanometer materials preparation, particularly relates to a preparation method of monodisperse polystyrene microspheres capable of controlling the particle size of the polystyrene microspheres within a certain range by changing the use amount of a stabilizer. The invention prepares polystyrene microspheres with simply purified styrene as a monomer, potassium persulfate as an initiator, water as a reaction medium and polyvinylpyrrolidone as a stabilizer by using soap-free emulsion polymerization. The preparation method uses electromagnetic stirring instead of electric stirring; and has the advantages of relatively low requirements for the uniformity of stirring speed, no need of surfactant, simple process, and low cost. The obtained polystyrene microspheres have good monodispersity, and the particle size thereof can be controlled within the range of 250-1,400nm by changing the use amount of the stabilizer. The monodispersed polystyrene microspheres have important application value as a module or template in construction of photonic crystals, inorganic / organic nanometer composite materials and hollow micrometer / nanometer spheres.

Production of unsaturated fatty acid plant sterol ester is carried out by alcoholysis reacting for glycerin trilaurate of vegetable oil under action of methanol and catalyst to obtain fatty acid methyl ester, ester exchange reacting for fatty acid methyl ester and plant sterol under action of catalyst, removing un-reacted methanol and fatty acid methyl ester to obtain crude unsaturated fatty acid plant sterol ester, de-coloring and deodorizing to obtain the refined final product. It's cheap, harmless and non-toxic and can be used in food-industry production.

The invention discloses a water-soluble graphene-noble-metal nano-composite and a preparation method and application thereof. The nano-composite comprises a graphene lamina and noble metal nano-particles covalently bonded on the graphene lamina through L-gystein. The preparation method for the water-soluble graphene-noble-metal nano-composite comprises the following steps of: ultrasonically dispersing a graphite oxide nano-sheet in ultra-pure water; adding L-gystein hydrochloride and a reductive agent to perform a reduction reaction; adding a noble metal ion solution; and adding the reductive agent to perform the reduction reaction again to obtain the nano-composite. The nano-composite can be used as a conductive material. The nano-composite has the characteristics of high load rate, good water solubility and biocompatibility, simple operation and environmental protection.

The invention provides a reaction method which is as follows: starting from simple and available imidazole salts, corresponding N-heterocyclic carbine-metal-imidazole complexes are synthesized; and then a Suzuki-Miyaura coupling reaction of aryl or heteroaryl boronic acid and aryl chloride by utilizing the complexes at room temperature under the condition of a water phase is carried out. The centers of metals related in the metal salts in the invention can be iron, copper, silver, nickel, palladium, cobalt, rhodium, ruthenium and the like. A catalyst used in the invention is easy to prepare, can be quantitatively synthesized and is stable to air and moisture. By using the catalyst, the corresponding coupling reaction is achieved under the condition that catalytic amount is only 0.01%, and yield is excellent. Compared with other systems reported in documents, the catalytic system is cheap in price, reaction is easy to operate and can be smoothly carried out at room temperature, and the requirement on reaction conditions is extremely low, thus the catalytic system has a good industrial application prospect.

The invention discloses a preparation method of phenolphthalein polyether sulfone containing a tertiary amine side group, which comprises the following steps of: (a) adding a halogenated organic matter monomer or a nitrified organic matter monomer, a catalyst and a solvent into a prepared phenolphthalein bisphenol monomer containing the tertiary amine side group to form a mixed solution; and (b) leading the mixed solution to react at 80-220 DEG C. The invention also discloses a phenolphthalein polyether sulfone homopolymer containing the tertiary amine side group and a phenolphthalein polyether sulfone copolymer containing the tertiary amine side group. The phenolphthalein or the phenolphthalein polyether sulfone is adopted as a raw material to generate substitution reaction with asymmetric amine to obtain the phenolphthalein polyether sulfone containing the tertiary amine side group. Because a tertiary amine group is a polar group and has higher hydrophily, the application limitation of the phenolphthalein polyether sulfone is overcome, and particularly, the adverse effect of the phenolphthalein polyether sulfone used as an ultrafiltration membrane or a reverse osmosis support base membrane applied to water treatment is eliminated. Meanwhile, the tertiary amine group has higher activity, is easy to convert into other groups, such as a quaternary amine group, and the like, and is beneficial to the further functionalization of the phenolphthalein polyether sulfone and the modification of a polyether sulfone product.

The invention belongs to the field of fluorescence detection materials, and particularly relates to a preparation method of a rare earth terbium-based metal organic framework material and study on the performance of selectively recognizing heavy chromate ions in water. By selecting rare earth terbium emitting green light as metal central ions and selecting p-terphenyl-3,3'',5,5''-tetramethyl acid as organic sensitized ligands, a rare earth porous metal organic framework compound is synthesized under the hydrothermal condition. The compound causes the most obvious fluorescence quenching phenomenon to Cr2O72- anions in different anion solutions, and thus the compound can serve as a novel fluorescence probe for detecting Cr2O72- anions.

The invention discloses an efficient salt-resistant dual-purpose thickening agent, a preparation method and application thereof. The preparation method of the thickening agent comprises the followingsteps of: S1, preparing a water phase; S2, preparing an oil phase; S3, performing emulsifying; S4, conducting polymerization; and S5, carrying out aftertreatment. A hydrophobic monomer, a functional monomer and a salt-resistant monomer are introduced into the thickening agent to form a compact and complex spatial network structure in an aqueous solution, so that the thermal stability and the saltresistance of the thickening agent are improved, and the aqueous solution of the thickening agent can keep relatively high viscosity under a hypersalinity condition. Due to the addition of a chain extender, the molecular chain of the polymer is longer, and the viscosity is greatly improved. A cosolvent is introduced, so that the dissolving speed of a polymer emulsion is further increased, the polymer emulsion can be completely dissolved in 30 seconds, the requirement on water quality is low, and the polymer emulsion can be prepared from oilfield reinjection water and oilfield wastewater. Due to the addition of a suspending agent, the emulsion system is more stable, and the emulsion is not layered within two years. The thickening agent also has the characteristic of dual purposes, and can be used as a fracturing fluid slickwater drag reducer and a fracturing fluid thickening agent.

The invention provides a vitamin E nanoemulsion, a nano cream and a preparation method thereof. The vitamin E nanoemulsion is composed of vitamin E, oil phase, main surfactant, cosurfactant and water.The average grain diameter of the vitamin E nanoemulsion is 30-60 nm, and the vitamin E nanoemulsion is an O / W type emulsion and is a uniform system which is transparent or semi-transparent, low in viscosity and good in mobility and has blue opalescence. The method for preparing the vitamin E nanoemulsion includes the steps of mixing an oil phase and vitamin E and performing stirring evenly; sequentially adding the main surfactant and the cosurfactant, and performing stirring evenly; slowly adding distilled water dropwise, performing stirring while adding water, and obtaining the vitamin E nanoemulsion. The vitamin E nano cream is made of the vitamin E nanoemulsion and the O / W type cream substrate, and the manufactured nano cream is white, fine, glossy and good in viscosity. Instruments required for the preparation method and operation steps are simple, and the prepared nano cream is good in stability and high in infiltration capacity and has good application prospect in the directionof cosmetics.

The invention discloses a method for modifying the surface of nano calcium carbonate. The method comprises the steps that 1, lime milk is added to a bubbling carbonatation reaction kettle, mixed gas containing carbon dioxide is introduced to the reaction kettle for a carbonatation reaction, carbonatation is conducted till the pH is equal to 7.0, carbonatation is completed, and a nano calcium carbonate suspension solution is obtained; 2, a stabilizer is added to the nano calcium carbonate suspension solution, the temperature is controlled within 50-60 DEG C, and heat preservation is conducted for 20-30 min; 3, a fatty acid modifier is heated and melted in water, an emulsifier is added to the fatty acid modifier, stirring is conducted for 10-30 min, and a modifier emulsion is obtained; 4, the nano calcium carbonate suspension solution obtained in the second step is added to the modifier emulsion, stirring is conducted for 30-60 min, and then through filter-pressing dehydration, drying and smashing, a nano calcium carbonate product is obtained. The prepared nano calcium carbonate has the advantages of good dispersity and processability, low oil absorption value, high thixotropy and activation rate, good stability, pH value close to neutral and the like. The method is low in production cost and simple in technology, facilitates industrial production and has good economic, social and ecological benefits.

The invention discloses a method of recovering platinum group metals based on copper capture. The method comprises the steps that platinum group metal contained waste is proportionally mixed with a copper capturing agent, an additive and a binding agent, and is subjected to fine grinding and then water adding to be pelletized, dried, placed in a crucible, and reduced at a certain temperature after certain reducing coal is added; metallized pellets obtained by reduction are broken, and the broken metalized pellets are subjected to ball milling and then gravity separation; and obtained ore concentrate is metal copper powder containing the platinum group metals, thereby realizing the recovery of the platinum group metals. The method is simple in technological process; and the reduction temperature is low; used equipment is conventional metallurgy and ore-dressing equipment, so that the method is easy to implement; a recovery rate of the platinum group metals is greater than 99%; the content of the platinum group metals in gravitation separation tailings is less than 10g / t; with the adoption of the method, the platinum group metals can be effectively recovered from spent auto-catalysts, catalysts for petrochemical industry and catalysts for fine chemicals; no harmful gas is discharged; the tailings can serve as raw building materials; and the whole process is clean and pollution-free.

A poly-p-dioxycyclohexanone / montmorillonite nano-composition is prepared from poly-P-dioxycyclohexanone and montmorillonite nanoparticles through proportionally mixing, stirring, heating, adding catalyst and reacting. Another preparing process is also disclosed. Said nano-composition features high mechanical and thermal performance, low reaction condition and high molecular weight.

The invention discloses a preparation method of organic siloxane microspheres with narrow particle size distribution and richly organized surfaces. The preparation method comprises the steps of (1) adding an anionic surfactant and a polymer stabilizer into deionized water, and mechanically stirring to prepare a dispersion liquid; (2) adding a siloxane monomer into the dispersion liquid, mechanically stirring for a certain period of time under a constant-temperature condition, and then adding a basic catalyst to initiate a reaction for a certain period of time to prepare a siloxane microsphere mixed liquid; (3) adjusting the pH value of the microsphere mixed liquid to a certain range, adding a silane monomer rich in organic groups, and stirring to react for a certain period of time to ensure that the silane monomer rich in organic groups is grafted to the siloxane microspheres through the reaction; and (4) centrifuging the reaction product to obtain a solid, and washing and drying to obtain the organic siloxane microspheres with narrow particle size distribution and richly organized surfaces. The preparation method disclosed by the invention is simple, is low in reaction condition requirement and low in preparation cost, and the prepared organic siloxane microspheres is narrow in particle size distribution and low in surface polarity.

The invention relates to a new roflumilast intermediate compound and a preparation method thereof, and application of the intermediate compound in preparing roflumilast. The roflumilast prepared from the intermediate has the advantages of mild reaction conditions, low requirements for reaction conditions and equipment, fewer byproducts, high product purity and yield and low production cost, does not use palladium on carbon, carbon monoxide or any other high-cost high-toxicity reagent, and is suitable for large-scale industrial production.

The invention provides a green synthesis method for substituted ketone, i.e., the substituted ketone is synthesized through the reaction of methyl ketone and alcohol in the existence of inert gases or air under an alkaline condition. The method is mild in reaction condition and can be carried out in the existence of the inert gases or air; and a product is simple in treatment, separation and purification and high in recovery rate. The method has the advantages that no transition metal catalysts are needed, primary alcohol which is cheap and easy to obtain is used as an alkylating reagent, water is produced as a unique byproduct, not only is the synthesis cost greatly reduced, but also no transition metal residues remain, and no wastes and pollution are caused, thus the green synthesis method has favorable popularization and application potential.

The invention provides a preparation method of 4-vinylphenol. The preparation method comprises the following steps: carrying out pyrolytic reaction on a biomass material at the temperature of 200 DEG C-500 DEG C under the oxygen-free or oxygen-poor condition, collecting pyrolytic gas, wherein the biomass material is a biomass material containing ligin and cellulose; and condensing the pyrolytic gas so as to obtain the 4-vinylphenol. According to the method, the pyrolytic temperature of the biomass is controlled to 200 DEG C-500 DEG C, and at the temperature, 4-vinylphenol is generated by the pyrolysis of the biomass. The method provided by the invention is simple in process and short in reaction period, has no high requirements on reaction equipment and reaction conditions; and in addition, low-price wide-source reproducible biomass materials are used as raw materials, thereby obviously reducing the production cost of the 4-vinylphenol.

The invention relates to a method for preparing a water purifying agent poly-ferric sulfate chloride by utilizing iron-containing wastewater in potassium fluotitanate production. The invention adopts a technical scheme that: the iron-containing wastewater discharged in the potassium fluotitanate production is directly utilized as a raw material; copperas and industrial sulphuric acid are added to regulate the total iron concentration and the acidity; a phosphate-tartrate composite stabilizer is added into the raw material; and at normal pressure, Fe2+ in the mixture is oxidized into Fe3+ through an oxidizer at the temperature of between 60 and 90 DEG C and the mixture is hydrolyzed to generate the poly-ferric sulfate chloride. In the method, the iron-containing wastewater in the potassium fluotitanate production is fully utilized to prepare the high-efficient poly-ferric sulfate chloride, and defects of poor process effect on the iron-containing wastewater and severe secondary pollution in the prior art are overcome; and the zero emission of the wastewater in the potassium fluotitanate production is realized, and new pollution is not caused so as to achieve the aim of changing the waste into the treasure. The method has the advantages of simple process flow, mild conditions, easy operation and control, no need of special or complicated equipment, small investment, quick effect, obvious economic and environmental benefits, and convenient promotion and industrial production. The product of the invention is suitable to be used as a treatment agent for multiple kinds of industrial wastewater and domestic sewage, particularly for heavy sewage.

The invention discloses a doxorubicin prodrug, its preparation method and an injectable composition. The doxorubicin prodrug is formed by hydrazone key-type connection between MPEG and DOX. The preparation method of the doxorubicin prodrug is simple; requirements on reaction conditions are low; yield is high; and production costs are easier to control. The prodrug has low immunity and can effectively raise water solubility of doxorubicin. In addition, it will take a long time to remove the doxorubicin prodrug in vivo such that action time of the drug can be effectively prolonged. The doxorubicin prodrug has pH sensitivity and can release doxorubicin in situ in an acidic pH environment and simultaneously form PEG. The doxorubicin prodrug composition can be dissolved in an approximately-neutral aqueous solution to form an aqueous solution with stable performance. When pH changes to acid, supermolecule hydrogel can be formed within minutes. Long-acting in situ release of doxorubicin can be achieved. Doxorubicin diffusion can be effectively avoided. Functions of normal cells are influenced. Toxic and side effect of the drug is reduced.

The invention relates to a large-scale synthesis method of a two-dimensional graphene-like carbon material by using sodium citrate, which comprises the following step: in an oxygen-free environment, by using sodium citrate as a carbon source, respectively synthesizing an amorphous carbon material, a nitrogen-doped amorphous carbon material, a graphene-like carbon material and a nitrogen-doped graphene-like carbon material by regulating the mass ratio of the sodium citrate, graphitization catalyst and nitrogen dopant. The high-quality graphene-like carbon material is obtained at lower temperature under atmospheric pressure, thereby solving the technical problem of mass controllable production of the graphene-like-structure carbon material to some extent, and having wide application prospects.

The invention discloses a method for preparing octacosanol and triacontanol from rice bran wax, which comprises the steps of: adopting an oxide or a hydroxide of alkaline-earth metal as a hydrolyst; hydrolyzing the rice bran wax through ultrasonic waves; separating and extracting fatty alcohol with the adoption of ethanol as an extracting agent; and separating the octacosanol and the triacontanol through a molecular distillation technology. The alkaline-earth metal is the hydrolyst; the time of the ultrasonic hydrolysis reaction can be shortened for 10 hours or higher than that of the general method, specifically from 12-16 hours to 2 hours or lower; the hydrolysis ratio is improved by 2 times; and the hydrolysis product is easily separated from impurities and the mother liquid. The invention has the characteristics of low requirement on reaction condition, normal temperature and pressure, low toxicity of auxiliary raw materials, low production cost, short reaction time and high purity and is easy to industrialized production.

The invention discloses a preparation method of an anti-bacterial ultraviolet-resistant textile. The textile is placed into finishing liquor prepared from an aqueous solution containing an amino-terminated hyperbranched polymer or a modified amino-terminated hyperbranched polymer and zinc salt for dipping treatment to obtain the anti-bacterial ultraviolet-resistant textile. Or the textile is soaked in the aqueous solution containing the amino-terminated hyperbranched polymer or the modified amino-terminated hyperbranched polymer, and then is subjected to dipping treatment in a zinc salt solution, to obtain the anti-bacterial ultraviolet-resistant textile. After being finished by using the method, the textile is good in hand feeling, air permeability and washing fastness, and good in anti-bacterial and ultraviolet-resistant function durability. By adopting an in-situ one-step generation process, the method is simple and easy in operation.

The invention discloses a method and kit for utilizing a Mo-Sb antiluminosity method to detect a content of orthophosphate in water. The method comprises blending ammonium molybdate, antimony potassium tartrate and ascorbic acid to make a color developing agent, adding the color developing agent into a to-be-measured water sample to blend the color developing agent, then adding benzene sulfonic acid to enable the pH to be 0-1, fully blending and standing for over 3min, utilizing a spectrophotometer to measure the absorbance at the position of 880nm, and obtaining the content of orthophosphate in the to-be-measured water sample through an absorbance value according to a pre-measured standard curve. According to the method, by improving a strong acid medium, operation in measuring orthophosphate in the Mo-Sb antiluminosity method is simplified, danger is lowered, the detection speed is improved, and field operation is facilitated.

The invention discloses a polyurethane latent curing agent having the structural formula of R1-CH--N-R 2-N--CH-R3, wherein R1 , R2 and R3 are alkyl group or aryl group or alkylaryl group. The molecular weight of the latent curing agent is not higher than 300. The invention also discloses a one-component polyurethane waterproof coating using the above latent curing agent and a preparation method thereof. The invention provides a polyurethane latent curing agent with good stability, and the one-component polyurethane waterproof coating prepared from the polyurethane latent curing agent is more resistant to storage and has a longer shelf life. Unit mass of the polyurethane latent curing agent can provide more -NH2 groups. The dosage is small and the application cost is low. The polyurethane waterproof coating disclosed in the invention has little damage to human body, is environmentally friendly, has excellent storage stability, has excellent coating performance, excellent tensile strength and tear strength, and can be prepared directly by existing production process and production equipment. The production costs are low.

The invention discloses a method for preparing carbon nanotubes by use of biodegradable plastics. The method is characterized in that a biodegradable composite is prepared from the following materials by melt-bending method using an internal mixer or double-screw extrusion method or solution reaction method: (by mass) 85% to 99% of a biodegradable plastic, 0.6% to 10% of an organically modified layered compound and 0.4% to 5% of a catalyst; then a mixture containing carbon nanotubes is prepared by Muffle furnace method or tube furnace method; and finally the carbon nanotubes are produced by purification treatment. Based on the barrier effect of the layers of the organically modified layered compound on the pyrolysis product of the biodegradable plastic, the volatile components of the biodegradable plastic are transformed to the carbon nanotubes under the action of the catalyst. The method for preparing the carbon nanotubes simplifies the process and the equipment, reduces the requirements for reaction conditions, and adopts the easily-accessible and recyclable biodegradable plastic as carbon source, so as to not only reduce the energy consumption but also solve the problem of greenhouse gas emissions during the degradation process of the biodegradable plastic.

The invention provides a preparation method of phytosterin ester rich in oleic acid, which comprises the following steps: firstly, leading seed fat rich in oletic acid and ethanol to perform alcoholysis reaction under the action of catalyst to obtain fatty acid ethyl ester rich in oleic acid; secondly, leading the fatty acid ethyl ester rich in oleic acid and phytosterin to perform the ester exchange reaction under the action of the catalyst, and removing unreacted ethanol and redundant fatty acid ethyl ester so as to obtain crude phytosterin ester rich in oleic acid; thirdly, obtaining primrose yellow to white thick fluid by decoloring the phytosterin ester, i.e. refined phytosterin ester. The oleic acid content of the seed oil is more than 60 percent; and high-content oleic acid reduces the side reaction and improves the yield of the phytosterin ester. The preparation method does not use deleterious organic solvent and produce deleterious materials during the whole preparation, has lower requirement on reaction condition, and is suitable for industrial mass production of food.

The invention provides an environmental-friendly nitrile hydrolysis method. The hydrolysis reaction of a nitrile compound is catalyzed by using a base catalyst in an air condition, wherein the reaction temperature is from room temperature to 120 DEG C and the reaction time is 1-48 hours. According to the method, a nontransition metal catalyst which is low in price and small in toxicity is used, the nitrile is hydrolyzed directly in the air condition to obtain the first-grade amide. The reaction is mild in condition, easy to operate, and does not cause over-hydrolysis of the nitrile to reduce the yield rate of the target product amide, and therefore the product separation and purification are simple and easy, and high in recycling rate. The method is quite low in requirements for reaction condition and has good research and industrial application prospect.

The invention discloses red light emitting carbon quantum dots and a household microwave preparation method thereof. The method comprises the following steps: dispersing ammonium citrate in a glycerolsolvent, heating and stirring to form a solution, adding formamide, and uniformly stirring; putting the mixture into a household microwave oven for heating reaction, cooling to room temperature, adding absolute ethyl alcohol, uniformly mixing, centrifuging to obtain a precipitate, dispersing the precipitate in absolute ethyl alcohol, filtering by a filter head to obtain preliminarily purified carbon quantum dots, and carrying out silica gel column chromatography for secondary purification to obtain a red light emission carbon quantum dot solution. The emission wavelength of the red quantum dot solution is 650 nm, and the fluorescence quantum efficiency reaches 23%, the red light emission carbon quantum dot solution has fluorescence excitation independent luminescence characteristics, andis still in red light emission state under near ultraviolet excitation. The method provided by the invention has the advantages of operation simplicity, environmental protection, low cost, high yield,and the like, and the obtained carbon quantum dots are uniform in size, high in purity, stable in fluorescence, non-toxic and pollution-free, and have important application value in the aspects of biomedicine and optoelectronic devices.

The invention relates to a preparation method of a bright oil, which comprises the following steps: enabling light-weight deasphalted oil to be in contact with a solvent in which macro-molecule polycyclic aromatic hydrocarbon can be selectively dissolved, thus obtaining a wax-containing refined oil; enabling the wax-containing refined oil to be in contact with a dewaxing solvent, thus obtaining a dewaxed oil and a micro-crystalline wax paste; enabling a mixture of the dewaxed oil and hydrogen gas to be in contact with a hydrotreating catalyst, thus obtaining a first hydrogenated full distillate oil; respectively enabling a mixture of the first hydrogenated full distillate oil and hydrogen gas to be in contact with a hydroisomerizing catalyst and a hydrorefining catalyst, thus obtaining a second hydrogenated full distillate oil; and separating out the distillate of which the boiling point is higher than 500 DEG C from the second hydrogenated full distillate oil, wherein the distillate is the bright oil product. By using the traditional method, only a low-viscosity index bright oil product can be produced; or by using the conventional isomerization dewaxing method, a high-viscosity intermediate-base or mixed-base material of the bright oil can not be obtained. By using the preparation method provided by the invention, a bright oil product which has satisfactory kinematic viscosity, high viscosity index and low pour point and does not contain floccules at normal temperature can be produced, and the micro-crystalline wax can be produced as a byproduct.

The invention discloses a caprolactam preparation method. The method is characterized in that caprolactam is prepared from cyclohexanone through oximation and rearrangement, and the method comprises the following steps: carrying out a catalytic reaction on cyclohexanone, hydrogen peroxide and ammonia to generate cyclohexanone oxime, extracting and separating by using a solvent A, adding a solvent B to the above obtained oil phase, carrying out a Beckmann rearrangement reaction under the action of oleum, carrying out slaking flash evaporation separation on the obtained product, hydrolyzing, extracting by using water, and carrying out original process refining to prepare finished caprolactam. The method shortens the caprolactam production process flow, reduces the consumption of raw materials and energy, generates less ammonium sulfate than original technologies, and improves the quality of the caprolactam product.

The invention relates to the technical field of nanometer photocatalysts, in particular to a photocatalyst with a function of catalytically oxidizing alcohol to form aldehyde in a high-selectivity manner, and preparation and application of the photocatalyst. Palladium nanometer particles are uniformly loaded on the surfaces of bismuth oxychloride (BiOCl) ultrathin nanometer sheets to form the photocatalyst. The thicknesses of the BiOCl ultrathin nanometer sheets are 3-10 nm, the diameters of the BiOCl ultrathin nanometer sheets are 50-100 nm, the particle sizes of the palladium nanometer particles are 2-10 nm, and the mass fraction of the palladium nanometer particles in the photocatalyst is 1-3 wt%. The photocatalyst, the preparation and the application have the advantages that sunlight in full wave bands can be absorbed by the photocatalyst, separation of photo-induced carriers can be improved, the surface catalytic activity can be greatly improved, and the photocatalytic efficiencycan be comprehensively improved; the photocatalyst with the function of photocatalytically selectively oxidizing the alcohol to form the aldehyde is high in catalytic efficiency and product selectivity as compared with other types of photocatalysts.