400 results about "Vacuum distillation" patented technology

The invention discloses a method for preparing 6N-grade high-purity zinc through twice vacuum distillation based on a uniform temperature field. The method comprises the following steps: pretreatment; first-stage distillation: putting the zinc ingot subjected to vacuum drying into a crucible of a vacuum distillation furnace, mounting a plurality of stages of condensation collecting trays on the top of the crucible in an overlapping manner, and then performing high-vacuum pumping, heating and heat preservation; second-stage distillation: after the heat preservation of the first-stage distillation is finished, heating and heat preservation are continued under high vacuum; a plurality of samples are respectively obtained from the multistage condensation collecting disc, and the samples with the zinc content not lower than 99.9999% are collected, namely the 6N-grade high-purity zinc product. According to the method, zinc ingots with the purity of 99.99%-99.995% are used as raw materials, a conventional vacuum distillation furnace is used as distillation equipment, multiple stages of condensation collecting plates are mounted on the top of a crucible in an up-and-down overlapping manner, a novel two-stage distillation process is developed in a matched manner, key parameters such as the vacuum degree, the heating temperature, the heating rate and the heat preservation time are accurately controlled, and the high-purity zinc ingot is obtained. And a 6N-grade high-purity zinc product is successfully prepared.

The invention discloses dibutyl adipate as well as a preparation method and application thereof, preparation raw materials comprise adipic acid, n-butyl alcohol and a catalyst, and the molar ratio of the adipic acid to the n-butyl alcohol to the catalyst is 1: (3-8): (0.001-0.005). Excessive n-butyl alcohol obtained through distillation and kettle residues obtained after vacuum rectification can be directly applied to the next batch of reaction, continuous circular reaction can be achieved by supplementing a small amount of catalyst, maximum utilization of raw materials is achieved, and the production cost is reduced. Compared with the product obtained by the prior art, the content of the product obtained by simple rectification is higher, the content of dibutyl adipate in the product is 99.8% or above, the risk of trace activated carbon residue after activated carbon adsorption treatment is avoided, and the cosmetic grade product standard is met.

The invention relates to a preparation method of soybean oil base polyhydric alcohol, in particular to a method for preparing soybean oil base polyhydric alcohol by directly using soybean oil. The soybean oil diluted by using a solvent reacts with hydrogen peroxide with the weight percentage being 30% for 2-5 hours at the temperature of 60-70 DEG C under catalysis of a catalyst with the weight percentage being 3-5%; vacuum distillation is conducted after the reaction is ended, and the solvent is evaporated; then low alcohol is added in a reactor to be subjected to a reaction for 4-6 hours under the pressure of 0.3-0.4 MPa and at the temperature of 70-80 DEG C, then the reaction is stopped, and the soybean oil base polyhydric alcohol is obtained. The method saves the using amount of hydrogen peroxide, reduces the post-treatment steps, and simplifies the production procedures, and accordingly the product cost is declined directly.

The invention relates to the technical field of organic chemical synthesis, and discloses a continuous production process of a cationic etherifying agent, which comprises the following steps: taking trimethylamine hydrochloride and epoxy chloropropane as raw materials; the method comprises the following six steps: raw material pretreatment, premixing, continuous reaction, continuous separation, refining and product storage: mixing and dissolving trimethylamine hydrochloride and a solvent, preparing a catalyst solution, uniformly mixing the three materials through a static mixer, feeding into a multi-stage tubular reactor, and carrying out segmented temperature control continuous reaction, and performing flash evaporation solvent removal and rectification on the reaction product to obtain a crude product, and performing ion exchange impurity removal and reduced pressure distillation refining to finally obtain a high-purity product. The method solves the problems of low yield and more byproducts in the traditional process, and is suitable for industrial large-scale production.

The invention provides a process for preparing high-purity lithium sulfide through layer interface induction strengthening, which comprises the following steps: dissolving lithium chloride and sodium sulfide in N-methyl pyrrolidone, and stirring to form uniform slurry; pumping the obtained slurry into a fixed bed reactor filled with a molybdenum disulfide catalyst layered module, and reacting to obtain turbid liquid; performing temperature-controlled crystallization on the turbid liquid, filtering and separating to obtain sodium chloride crystals; performing reduced pressure distillation on the filtrate to obtain a lithium sulfide crude product; and dissolving the lithium sulfide crude product in absolute ethyl alcohol for washing, and carrying out suction filtration and drying to obtain lithium sulfide. According to the method disclosed by the invention, fixed bed catalytic reaction and programmed cooling crystallization separation are integrated, and process parameters are optimized, so that the core pain points of high energy consumption, poor safety, difficulty in separation, easiness in catalyst deactivation and the like in a traditional method are successfully solved; a green closed loop of the whole process flow is realized, and a reliable technical path is provided for industrial production of the high-performance lithium sulfide material.

The present application relates to a kind of dimethylamine piperidine continuous synthesis dimethylamine piperidine method of oxy group, by using reaction raw material mixed solution into continuous flow packed bed reaction zone, i.e.catalyst layer;Reaction temperature is 20-80 ℃, normal pressure, feed liquid is the mixture of dimethylamine piperidine, hydrogen peroxide and deionized water, oxidation is carried out on the catalyst layer of continuous flow packed bed adiabatic reactor to make dimethylamine piperidine into dimethylamine piperidine oxy group, realize the continuous preparation of dimethylamine piperidine oxy group;The obtained reaction liquid is quenched, then filtered to remove solid particle quenching agent, vacuum distillation to remove water and vacuum rectification treatment obtain high-purity dimethylamine piperidine oxy group;The process scheme overcomes the series of deficiencies in the previous preparation process, such as complicated steps, low product purity, low production capacity in unit production time, realizes the continuous preparation of high-purity dimethylamine piperidine oxy group, with the characteristics of efficient, safe, green manufacturing.

The application belongs to the technical field of oil and gas field development, and particularly relates to a temperature-resistant and salt-resistant foaming agent for drilling and a synthesis method thereof. The synthesis method is as follows: diphenylamine-4-sodium sulfonate, isopropyl alcohol and 1,3-dibromopropane are added into a four-necked flask, stirred, heated and refluxed to obtain a mixed solution; 90-95wt% of isopropyl alcohol in the mixed solution is distilled off under reduced pressure, distilled water is added, and the whole is transferred into a separatory funnel, fully shaken, separated, and a small amount of oil phase is discarded; the pH is adjusted to 2-3, a precipitate is separated out, suction filtration is performed, and an intermediate is obtained; the intermediate is transferred into a four-necked flask with isopropyl alcohol, sodium bromoethyl sulfonate is added, the pH is adjusted to 7-8, and the product solution is obtained by heating and refluxing; the product is obtained by vacuum distillation, recrystallization and drying. The foaming agent for drilling has the advantages of good temperature resistance, salt resistance and salinity resistance.

The invention belongs to the field of organic synthesis, and particularly relates to a method for preparing trimesoyl chloride in an immobilized catalysis mode. An immobilized catalyst is used as an acyl chloride reaction catalyst, thionyl chloride and benzene tricarboxylic acid are used as raw materials, and direct boiling reflux reaction is performed under the condition of not introducing other solvents; after the reaction is finished, filtering out the catalyst, and terminating the reaction; and then carrying out reduced pressure distillation to remove excessive reactant thionyl chloride, and then carrying out vacuum distillation to obtain the product trimesoyl chloride. By adopting the immobilized catalyst and taking the raw material as the reaction solvent, the method has the characteristics of mild reaction, simple process, high reaction speed, high product purity, high product yield and the like. And the immobilized catalyst and the reactant thionyl chloride can be recycled, so that the cost is saved, the reaction tail gas is easy to treat, the environmental pollution is not easily caused, and the method is suitable for industrial production. The final product is trimesoyl chloride, the purity can reach 99.2% or above, and the yield reaches 92% or above.

This invention provides a method for preparing dibenzoyl-p-benzoquinone dioxime using a microchannel reactor. The method includes the following steps: 1,3-dicyclohexylcarbodiimide and a catalyst are mixed uniformly and preheated to obtain a premix; a chloroform solution of p-benzoquinone dioxime, a chloroform solution of benzoic acid, and the premix are simultaneously introduced into the microchannel reactor for reaction; the resulting reaction solution is subjected to vacuum distillation, washing, filtration, and drying to obtain dibenzoyl-p-benzoquinone dioxime. The synthesis method of this invention features high reaction conversion rate, high production efficiency, few side reactions, and high safety. The obtained dibenzoyl-p-benzoquinone dioxime product has stable quality. Furthermore, the organic solvent used can be recovered and reused after vacuum distillation, overcoming the problems of inaccurate temperature control, poor safety, numerous side reactions, and difficult waste treatment in traditional processes. This provides a new approach for the synthesis of dibenzoyl-p-benzoquinone dioxime.

The utility model discloses a coking anti-blocking mechanism for a second-line distillation outlet of reduced pressure distillation, and particularly relates to the technical field of distillation kettles, the coking anti-blocking mechanism comprises a distillation kettle, a first distillation port and a second distillation port are respectively arranged on the distillation kettle, and a mounting groove is arranged in the second distillation port. A plurality of heating pieces which are arranged in a linear array are arranged in the mounting groove, an outlet pipe is arranged on the second distillation opening, and a plurality of guide grooves which are arranged in a linear array are formed in the outlet pipe. According to the distillation kettle provided by the utility model, exhaust and liquid discharge are realized through the first distillation port and the second distillation port on the distillation kettle, installation of a plurality of heating elements is realized through the installation groove of the second distillation port, liquid discharge is realized through the outlet pipe on the second distillation port, and liquid is guided through a plurality of guide grooves on the outlet pipe; the liquid flow rate is increased.

This invention provides a method for preparing high-purity imidazole ionic liquids, comprising the following steps: S1: 1-Ethyl-3-methylimidazolium chloride, sodium trifluoromethanesulfonate or sodium bis(trifluoromethanesulfonyl)imide, and glycerol solvent are added sequentially to a reactor, followed by stirring and reaction; S2: After the reaction is completed, stirring is turned off, and the resulting crude 1-ethyl-3-methylimidazolium ionic liquid and glycerol mixture are filtered and collected in a separator, with sodium chloride retained in the reactor and subsequently discharged; S3: Pure water is added to the separator, and the separator is stirred for a certain period of time before settling and separation; S4: The two phases in the separator are separated by a separator and then enter their respective purification devices; S5: The crude 1-ethyl-3-methylimidazolium ionic liquid is dehydrated by vacuum distillation to obtain the product; S6: The water and glycerol mixture is distilled under reduced pressure to obtain a reusable aqueous phase and a glycerol phase. This invention yields a product with a purity of over 99.5%; the solvents glycerol and water are reused after distillation. This method is simple, has a yield of over 94%, and is easy to implement in large-scale production.

Disclosed in the present invention is a method and system for preparing a starting material of a carbon material by means of staged hydrogenation of heavy oil. The method comprises: sequentially performing pretreatment, hydrogenation pretreatment, and vacuum distillation on heavy oil; performing selective hydrogenation treatment on a middle distillate obtained by vacuum distillation; performing hydrogenation ring-opening treatment on a heavy distillate obtained by vacuum distillation; and then performing post-treatment on a product obtained by the selective hydrogenation treatment and a product obtained by the hydrogenation ring-opening treatment, so as to obtain a starting material of a carbon material. The starting material of the carbon material prepared by the present invention has a relatively high content of tricyclic aromatic hydrocarbon and a relatively high content of tetracyclic aromatic hydrocarbon, and a relatively low content of impurities, and can be used for preparing a high-quality carbon material.

The application discloses a method for detecting low-concentration urea in reclaimed water and a continuous online monitoring device, and belongs to the technical field of water quality monitoring equipment. The method comprises the following steps: adding sulfuric acid solution into a water sample to be detected to adjust pH to 3-5, then adding sodium dodecyl sulfonate and ethylenediaminetetraacetic acid to form a urea stable system; concentrating the water sample by vacuum distillation under the condition of 60-80 DEG C; adding a chromogenic reagent and a stabilizing reagent into the concentrated water sample, and reacting under the condition of 65-75 DEG C for 10-15 minutes; and determining the absorbance by using an ultraviolet detector and calculating the urea content. The application further provides a continuous online monitoring device for realizing the method. The application can accurately detect low-concentration urea below 80 mu g / L, the single detection time is less than 30 minutes, the anti-interference capability is strong, and full-process automatic control is realized.

The application provides a photoresist waste liquid recycling device and process, by adding hydrochloric acid to the photoresist waste liquid in the acidification precipitation tank in the pretreatment module to adjust the pH value, the linear phenolic resin precipitation rate reaches more than 95%, and the linear phenolic resin can be used again to the production stage of the photoresist after centrifugal separation, a compound coagulant containing sulfide and polyaluminum chloride is added to the heavy metal capture tank in the pretreatment module, and the removal rate of heavy metal ions reaches 99.5%; then the photoresist fragments are separated by using an ultrafiltration device, and the diatomite modified by NaOH and polyetherimide is used for adsorption and decolorization, then two-stage vacuum distillation process is used to realize the recovery of high-purity solvents in the photoresist waste liquid, finally, the remaining residue is polymerized and cured by ultraviolet radiation, and the solid fuel with high heat value can also be prepared, so that the 'zero emission' and resource full recovery of the photoresist waste liquid are realized, and the treatment cost and environmental risk are significantly reduced.

The application discloses a catalyst for preparing malononitrile, a preparation method of the catalyst and a method for preparing malononitrile by using the catalyst. The catalyst is a solid catalyst, which is an acidic catalyst loaded with rare earth metal oxide. The method for preparing malononitrile is that cyanoacetic acid or cyanoacetate or cyanoacetamide and an ammonia source are subjected to ammoniation dehydration reaction in a continuous reactor to prepare malononitrile according to a certain molar ratio. Then, vacuum distillation (20 torr-25 torr) is carried out, and a fraction collected at 110 DEG C-120 DEG C is malononitrile product. The ammonia source can be ammonia gas, ammonia water, ammonium carbonate or urea. The method for preparing malononitrile can reduce production cost, improve production safety, reduce the discharge amount of three wastes in the preparation of malononitrile by using an existing process, and improve product quality, and is a sustainable and green synthesis route.

This invention relates to the field of organosilicon compound synthesis technology, specifically to a method for preparing pentaphenyltrimethyltrisiloxane and its application. The preparation method includes: S1, mixing diphenylmethylchlorosilane and methylphenyldichlorosilane for co-hydrolysis to obtain an intermediate raw material; S2, adding a catalyst to the intermediate raw material under vacuum to carry out a catalytic polymerization reaction to obtain a polymer product; S3, vacuum distilling and extracting the target component from the polymer product obtained in step S2 to obtain pentaphenyltrimethyltrisiloxane. The preparation method of this invention, by adjusting the raw material ratio, selecting a suitable catalyst, controlling its dosage, limiting the polymerization process parameters, and precisely controlling the distillation separation conditions, achieves a product purity of over 99% and a refractive index stable between 1.5765 and 1.5790, while also improving industrial production efficiency and meeting the product quality requirements of high-end fields.

The invention belongs to the field of valuable metal recovery and arsenic harmless treatment, and particularly relates to a preparation method of crude arsenic. The preparation method of the crude arsenic comprises the following steps: putting an arsenic-containing material into a container of a vacuum distillation device, and sequentially carrying out vacuum distillation and condensation to obtain crude arsenic with the purity of 99% or above in an arsenic condensation area; the arsenic-containing material comprises a high-arsenic alloy; the temperature of vacuum distillation is 470-550 DEG C; and the arsenic condensation area is arranged at a position 40-50mm above the opening of the container. By adopting a vacuum distillation mode, arsenic is volatilized and condensed to a target area (an arsenic condensation area), and other elements are difficult to volatilize or condense to the area. The method is easy to operate, the vacuum distillation temperature is low, and the crude arsenic with the purity being 99% or above can be obtained only through one-time distillation. According to the method, crude arsenic easy to store is prepared while the high-arsenic alloy is treated, subsequent arsenic oxidation is avoided, and the method has the advantages of being environmentally friendly, efficient, high in recovery rate and free of chemical reagent consumption.

The application discloses a triphenylmethane polyether dye and a preparation method thereof, and the preparation method comprises the following steps: (1) adding an organic catalyst and an oxidant into a triphenylmethane polyether dye leucoaqueous solution in the interval of 40-60 DEG C, adding an acid-binding agent to maintain a proper pH, and completing oxidation; the organic catalyst is a ferrocene-rotene iron compound; (2) adjusting the pH with an acid-binding agent aqueous solution, removing the organic catalyst by hot filtration, removing water through vacuum distillation of the filtrate, and performing pressure filtration to obtain the triphenylmethane polyether dye. The improved rotene iron catalyst is used in the application, the catalytic effect is obviously improved, the reaction temperature and activation energy are reduced, the defects of excessive hydrogen peroxide oxidation are overcome, and the obtained product meets the EN71-3 standard.

The invention relates to a method for recovering valuable metal from lead-antimony alloy by using a vacuum distillation process, and belongs to the technical field of metallurgical engineering. The method comprises the following steps that (1) a raw material lead-antimony alloy is subjected to primary vacuum distillation in a vacuum furnace, in the primary vacuum distillation process, Pb, Sb and Bi elements with low boiling points are volatilized preferentially, and volatile matter lead-antimony-bismuth alloy mainly containing Pb, Sb and Bi and residual copper-silver alloy rich in Cu and Ag are obtained; wherein the raw material lead-antimony alloy mainly comprises the following chemical components (wt%): 38-40% of Sb, 39-42% of Pb, 1-3% of Cu, 5-7% of Bi, 0.5-3% of As and 0.5-3% of Ag; (2) carrying out secondary vacuum distillation on the volatile matter lead-antimony-bismuth alloy in a vacuum furnace to obtain a lead-antimony alloy and a bismuth alloy; wherein the process conditions of the secondary vacuum distillation in the vacuum furnace are as follows: the temperature is kept at 450 DEG C for 10-15 minutes, the temperature is kept at 500 DEG C for 10-15 minutes, the temperature is kept at 550 DEG C for 10-15 minutes, the temperature is kept at 700 DEG C for 3-5 hours, and the vacuum degree is 5-10

The invention discloses a preparation method of liquid aliphatic secondary amine, which comprises the following steps: 1, carrying out reductive alkylation reaction on aliphatic secondary amine, 3, 3-dimethyl-2-butanone and hydrogen under the action of a platinum-carbon catalyst and a sulfur-containing organic matter; and 2, filtering the reaction mixture, and carrying out vacuum distillation to obtain the target product. According to the method, hydrogen is used as a reducing agent, the process is green and environment-friendly, side reactions are few, and the purity of the prepared aliphatic secondary amine can reach 98% or above. The preparation method comprises the following steps: dissolving trace dimethyl sulfoxide in an ethanol solution to form a dimethyl sulfoxide-ethanol dispersion mixed solution, adding the dimethyl sulfoxide-ethanol dispersion mixed solution into a high-pressure hydrogenation reaction kettle, fully mixing the dimethyl sulfoxide-ethanol dispersion mixed solution with an obtained imine mixture, and adding a platinum-carbon catalyst. The preparation method of the liquid aliphatic secondary amine, which is disclosed by the invention, has the advantages of high catalyst selectivity and strong activity, and is suitable for producing the liquid aliphatic secondary amine.

The utility model discloses a noble lead vacuum distillation furnace, which relates to the technical field of vacuum distillation furnaces and comprises a discharge box, a vacuum distillation furnace component is fixedly mounted at the top of the discharge box, and a feeding component is fixedly mounted at the top of the vacuum distillation furnace component. According to the noble lead vacuum distillation furnace disclosed by the utility model, the third inserting plate type valve and the second inserting plate type valve are respectively arranged at the two ends of the feeding box, and the gas inlet pipe is used for filling protective gas into the feeding box through the gas inlet pipe before materials are fed, so that the materials fall into the crucible through the material guide pipe; by arranging the discharging box, the interior of the vacuum distillation furnace assembly is still in a vacuum state when the vacuum distillation furnace assembly is discharged, the vacuum distillation furnace assembly rapidly enters a machining state, meanwhile, discharging of a traditional discharging pipe is avoided, and the production efficiency of the vacuum distillation furnace assembly is improved. Corrosion and replacement of the discharge pipe are avoided, and the use cost is reduced.

The application belongs to the technical field of oil exploitation, and particularly relates to an acid liquid for acid treatment of an oil layer and a preparation method thereof. The preparation method is as follows: the specific steps of the preparation method are as follows: in a reactor, piperazine-1,4-diethyl sulfonate monosodium salt, ethanol and bromoalkane are added, heated to reflux, and during the reaction, sodium hydroxide solution is used to maintain pH 7-8; 1-bromo-6-(trimethylammonium) hexyl bromide is added, heated to reflux, and during the reaction, sodium hydroxide solution is used to maintain pH 8-9; vacuum distillation is performed to obtain a viscous solid, cyclohexane recrystallization is performed to obtain a solid, and the solid is dried at 90 DEG C overnight to obtain corrosion-inhibiting acid; hydrochloric acid, hydrofluoric acid, hydroxyethylidene diphosphonic acid, corrosion-inhibiting acid and water are added to the reactor, stirred uniformly, and the acid liquid is obtained. The acid liquid has the advantages of low corrosion rate and long acidification time.

The application discloses a synthesis method of aza-cyclic modified hydroxyalkyl diethanolamine borate linking agent, which comprises the following steps: (1) adding hydroxyalkyl diethanolamine and boric acid into a three-neck flask provided with a stirrer, a thermometer and a vacuum distillation device, and stirring and heating to react until no water is generated; (2) adding an aza-cyclic compound into the reaction system obtained in the step (1), increasing the reaction temperature, and removing water generated in the reaction by vacuum distillation when no water vapor is generated, so as to obtain a target product. The borate linking agent obtained by the synthesis method has good hydrolysis resistance, and when the borate linking agent is used in a hydroxyl-terminated solid propellant, the mechanical properties of the hydroxyl-terminated solid propellant can be effectively improved.

The invention discloses a preparation method of high-purity 2-fluoroethanol, and particularly relates to the technical field of preparation of 2-fluoroethanol, which comprises the following steps: S1, in a dual-catalyst system consisting of a phase transfer catalyst and a Lewis acid catalyst and an organic solvent, carrying out fluoridation reaction on 2-chloroethanol and anhydrous potassium fluoride at 60-120 DEG C for 2-10 hours to obtain 2-chloroethanol; and S2, sequentially carrying out integrated purification of filtration, reduced pressure distillation, adsorption treatment and rectification on the reaction mixture. According to the invention, through synergistic activation and mass transfer of double catalysts, the reaction rate and selectivity are significantly improved, the water segregator is utilized to remove reaction water to push equilibrium movement, the conversion rate is improved, and water and impurities are systematically removed by virtue of composite adsorption and precise rectification of molecular sieves and activated carbon, so that high-quality 2-fluoroethanol with high purity and low moisture is finally obtained. The whole preparation process is mild in condition, high in yield, good in safety and suitable for industrial production.

The invention discloses a method for synchronously extracting and separating pectin and polyphenol in pericarpium citri reticulatae, and belongs to the technical field of plant extraction.The method comprises the following steps that S1, pericarpium citri reticulatae powder is extracted in an organic weak acid water solution at the temperature of 65-75 DEG C; s2, continuously extracting in the organic weak acid / low-alcohol-content alcohol water solution under the condition of 50-60 DEG C; and S3, filtering while the solution is hot, cooling, slowly adding absolute ethyl alcohol until a precipitate is separated out, slowly cooling, keeping the temperature, standing, filtering, washing the solid to obtain a pectin extract, and carrying out reduced pressure distillation and extraction on the liquid to remove the solvent to obtain the polyphenol extract. The method comprises a step of sequentially extracting in an organic weak acid aqueous solution and an organic weak acid / low-alcohol-content alcohol aqueous solution, and a step of separating by filtering and precipitating, so that the synchronous extraction and separation of pectin and polyphenol can be realized, and higher yield and purity can be obtained.

The present utility model relates to a vacuum distillation receiver adaptor for use in laboratory and pilot-scale distillation systems operating under reduced pressure conditions. The adaptor comprises an inlet connection configured to receive vapor or condensate from a distillation apparatus, first and second outlet connections configured for attachment to corresponding collection vessels, and an internal flow passage configured to selectively direct flow between the inlet connection and the outlet connections. The adaptor further includes an outlet selector valve configured to selectively establish fluid communication with either outlet connection, an inlet isolation valve configured to isolate the adaptor from the distillation apparatus, and a vent valve configured to selectively equalize pressure within a selected outlet connection.

The utility model relates to distillation device technical field, and disclose a vacuum distillation device for separation and purification, including vacuum equipment, the vacuum equipment includes vacuum cavity, closing subassembly and vacuum subassembly, the opening of vacuum cavity is connected with closing subassembly through hinged rotation, the rear portion of vacuum cavity is connected with vacuum subassembly through bellow, the inside fixed connection of vacuum cavity has work platform, the upper portion fixed mounting of work platform has heating cage, the upper portion of work platform still installs fixed mould, the inside of fixed mould places distillation flask, fixed mould and distillation flask all are in the inside of heating cage, the raw material in distillation flask is played heating effect to heating cage, this distillation device has with vacuum equipment and separates the distillation raw material, avoids the dampness inside vacuum container, is convenient for vacuum subassembly to draw a vacuum to improve distillation separation efficiency.

This invention provides a device for recovering valuable metals from molten slag, comprising a vacuum distillation furnace. The vacuum distillation furnace contains graphite discs for condensation and a heating coil for temperature control. A discharge pipe is located at the bottom of the vacuum distillation furnace. The vacuum distillation furnace includes multiple vertically arranged temperature control zones. Multiple sets of graphite discs are arranged vertically, with a condensation zone formed between adjacent discs. Through holes are formed on the surface of each graphite disc to connect adjacent condensation zones. This invention enables molten slag to undergo multiple condensation separations with a single heating process, significantly shortening the metal separation cycle.

The application discloses a method for recovering lactic acid methyl ester by catalytic depolymerization of polylactic acid in one pot. The method comprises the following steps: mixing polylactic acid, amine nitrogen ligand and methanol, dissolving by adding a solvent, and then adding a n-butyllithium solution to carry out a depolymerization reaction; and after the reaction is completed, the solvent is removed by vacuum distillation, and the crude product is dried in vacuum to obtain lactic acid methyl ester product. The application does not need to synthesize a complex organic metal catalyst, the depolymerization condition is mild, and the generation of by-products such as low-molecular-weight oligomers is effectively reduced. Therefore, the application has the advantages of simplifying the catalyst preparation process, improving the depolymerization efficiency, reducing the cost and the like, and is suitable for industrialized recovery and cyclic utilization of polylactic acid.

The present application relates to the technical field of nuclear fuel cycle and radioactive waste treatment, in particular to a method and system for treating uranium-containing organic phase, the system comprises pretreatment washing tank, pyrolysis reactor, phase separation tank, uranium recovery device, vacuum distillation device, tail gas treatment device and solidification device connected in sequence; the method first removes acid by water washing pretreatment of uranium-containing organic phase at 40-50 DEG C, then adds phosphoric acid to catalyze pyrolysis to decompose TBP and transfer uranium to phosphoric acid phase, recovers uranium and n-dodecane after phase separation, simultaneously treats tail gas and solidifies residual waste, and further provides online monitoring and control subsystem to realize automatic control and safety interlocking; the present application has mild reaction condition, avoids strong corrosive substance generation, total uranium recovery rate reaches more than 90%, about 80% of n-dodecane can be recycled, greatly reduces radioactive waste production amount, is safe and reliable in operation, and is suitable for radioactive waste organic extractant reduction and resourceful treatment in nuclear fuel cycle.