130results about How to "High purity" patented technology

It is an object of the present invention to provide, for the case of continuously producing aromatic carbonates containing a diaryl carbonate as a main product by taking an alkyl aryl carbonate as a starting material, which is obtainable through a transesterification reaction between a dialkyl carbonate and an aromatic monohydroxy compound, using a continuous multi-stage distillation column in which a catalyst is present, and continuously feeding the starting material into the continuous multi-stage distillation column, a specific process that enables the diaryl carbonate to be produced with high selectivity and high productivity stably for a prolonged period of time on an industrial scale of not less than 1 ton per hour. Although there have been various proposals regarding processes for the production of aromatic carbonates by means of a reactive distillation method, these have all been on a small scale and short operating time laboratory level, and there have been no disclosures whatsoever on a specific process or apparatus enabling mass production on an industrial scale. According to the present invention, there is provided a specified continuous multi-stage distillation column, and there is also provided a specific process that enables a diaryl carbonate to be produced with high selectivity and high productivity stably for a prolonged period of time on an industrial scale of not less than 1 ton per hour from an alkyl aryl carbonate.

This invention provides a process of preparing reaction-derived decabromodiphenyl oxide product of high purity. The process comprises feeding a solution comprising a solvent and diphenyl oxide and/or partially brominated diphenyl oxide into a reaction zone containing a refluxing reaction mixture comprising an excess of bromine and a catalytic amount of Lewis acid bromination catalyst. Substantially concurrently with the feeding, a sufficient amount of hydrogen bromide coproduct is removed from the reaction zone so as to form a reaction-derived decabromodiphenyl oxide product of high purity.

The invention discloses a preparation method of a furfural-modified lignin-based phenolic resin adhesive and belongs to the technical field of the biomass energy chemical industry. According to the method, a xylose solution is prepared from biomass hemicellulose through hydrolysis under catalysis of diluted acid, furfural is prepared through dehydration of xylose under catalysis of concentrated acid, lignin is extracted under catalysis of alkali, and an alkali lignin solution is obtained; alkali lignin is subjected to phenolation modification with phenol as a phenolation reagent and alkali as a catalyst, phenol is replaced with the modified lignin in different proportions, formaldehyde is replaced with furfural in different proportions, and the lignin-based phenolic resin adhesive is prepared through collaborative copolymerization of lignin, furfural, phenol and formaldehyde. The product furfural prepared through hydrolysis and dehydration of hemicellulose is taken as a crosslinking agent, the industrial application problem that the glue strength of the adhesive is reduced due to the fact that the proportion of lignin replacing phenol is increased in the prior art is solved, and the total replacement rate of chemical products from biomass for phenol and formaldehyde from fossil resources is increased.

The invention discloses a production method for simultaneously preparing metal manganese and manganese dioxide in an ion exchange membrane electrolytic method. An electrolytic bath is successively divided into a cathode chamber, a septation chamber and an anode chamber by utilizing an anion exchange membrane and a cation exchange membrane, a cathode and an anode as well as a cathode solution and an anode solution are respectively correspondingly arranged in the cathode chamber and the anode chamber, the cathode solution is a manganese sulfate solution comprising additives and a buffering agent, the anode solution is an acidic manganese sulfate solution comprising a surfactant, and the septation chamber is filled with a thin sulfuric acid solution; and when the constant-current electrolysisis performed, the manganese ions reduce metal manganese element on the cathode, the manganese dioxide electric deposition reaction occurs on the cathode, and 1mol/L to 2mol/L of sulfuric acid solution can be obtained in the septation chamber by virtue of electrochemical regeneration manner. By adopting the production method, the electric deposition of manganese on the cathode and the electrolyticgeneration of manganese dioxide on the anode can be simultaneously performed, the current efficiency is high, the environmental pollution is light, and a sulfuric acid byproduct can be produced and can be recycled to the anode solution, so that the reutilization of the resource can be realized; and a metal manganese product and manganese dioxide product are good in quality and high in purity.

The invention relates to a method for preparing thin-diameter zirconium oxide fibers and a fiber board thereof. The method comprises the following steps of: preparing poly zirconium sol spinning solution by adopting basic zirconium carbonate, glacial acetic acid, water and yttrium nitrate as raw materials, obtaining thin-diameter poly zirconium sol fibers by ultrahigh-speed centrifugal swinging and high-speed hot airflow blowing and drafting, and performing thermal treatment and sintering on the thin-diameter poly zirconium sol fibers to obtain the thin-diameter zirconium oxide fibers; and performing vacuum suction molding and pressure leveling to prepare a wet fiber board blank by adopting the thin-diameter zirconium oxide fibers as a raw material and adopting poly zirconium sol spinningsolution diluted by adding water as adhesive, and drying and calcining the wet blank to obtain the zirconium oxide fiber board. The raw materials are easily obtained, the preparation of the adhesive is simple and convenient, and the method has low cost and no pollution and is suitable for large-batch industrialized production; the prepared thin-diameter zirconium oxide fibers have good bending flexibility; and the prepared zirconium oxide fiber board has uniform thickness, flat surface, accurate and controllable thickness, and good mechanical property and high-temperature bending resistance.

Crystalline raloxifene hydrochloride in hydrated form, particularly the monohydrate, processes for its preparation, pharmaceutical compositions comprising it and uses thereof.

The invention discloses a feed-grade manganese sulfate production control system based on visual technology. Compared with a production control system of high-purity manganese sulfate in the prior art, the production control system further comprises a crystallization module for carrying out automatic evaporative crystallization treatment on mixed mother liquor, a control module for further controlling the generation condition of crystals in the crystallization module based on an image technology, an extraction module for extracting the crystallized crystals which are crystallized in the crystallization module, and a packaging module for carrying out moisture constancy and sieving treatment on the crystallized crystals in the extraction module and further carrying out quantitative packaging treatment. Meanwhile, the crystallization step in the manganese sulfate production control system is automatically monitored, so that the generation condition of the crystallized crystals is effectively judged, and the production efficiency of the production control system is effectively improved.

The invention provides a device and method for continuously producing lithium chloride from salt lake lithium-rich brine. The above-mentioned device includes: a continuous buffering and homogenizing unit, which has a salt lake lithium-rich brine inlet and a buffering and homogenizing brine outlet; a continuous magnesium removal unit, which has a buffering and homogenizing brine inlet and a magnesium-removing brine outlet, a buffering and homogenizing brine inlet and a buffering and homogenizing brine. The outlet is connected, and the continuous magnesium removal unit is used to remove magnesium ion impurities in the buffered and homogenized brine discharged from the outlet of the buffered and homogenized brine, so as to obtain the magnesium-removed brine; the multi-effect falling film evaporator has the magnesium-removed brine inlet and the concentrated brine outlet, The magnesium-removing brine inlet is connected to the magnesium-removing brine outlet; the single-effect evaporative crystallizer has the concentrated brine inlet and the lithium chloride crystallization outlet, and the concentrated brine inlet and the concentrated brine outlet are connected; the continuous drying unit is connected to the lithium chloride crystallization outlet, using For drying the lithium chloride crystals. The above device can effectively separate lithium chloride from lithium-rich brine in salt lakes in a shorter process.

The invention relates to the technical field of lithium chloride in the PPS industry, and discloses a method for recovering the lithium chloride from bottom residue slurry containing the catalyst lithium chloride; the following steps are performed: 1, the bottom residue slurry containing the catalyst lithium chloride is with pure water to obtain diluted bottom residue slurry; and 2, the diluted bottom residue slurry is filtered to obtain first filtrate. The method for recovering the lithium chloride from the bottom residue slurry containing the catalyst lithium chloride greatly improves the recovery rate of the lithium chloride compared with the method in the prior art, and the purity of the obtained solid lithium chloride is high; and the lithium chloride in the bottom residue slurry is fully extracted. The solid lithium chloride recovery process is kept in an aqueous solution, and the recovery temperature is moderate. During the recovery process of the lithium chloride, NMP is not easy to decompose, and the environmental pollution problems caused by black dense smoke produced by decomposition of NMP can be greatly reduced.

The invention discloses a synthesis method of hexafluorocyclotriphosphazene, which comprises the following steps: dissolving hexachlorocyclotriphosphazene in an organic solvent, adding a fluorinatingagent and a catalyst, carrying out fluorination reaction, and rectifying to obtain the target product hexafluorocyclotriphosphazene. The synthesis method of hexafluorocyclotriphosphazene has the advantages of mild reaction temperature, simple and easy-to-operate process, high yield, short time consumption, high purity, greenness, economy and convenience in industrial production.

The invention relates to a synthesis process of quizalofop-p-ethyl active compound, which comprises the following steps: carrying out esterification reaction on (R)-2-[4-(6-chloroquinoxaline-2-yloxy)]propionate and halogenated ethane as raw materials to synthesize quizalofop-p-ethyl, and reacting (R)-2-[4-(6-chloroquinoxaline-2-yloxy)] propionate with 2, 6-dichloroquinoxaline as a raw material through (R)-(+)-2-(4-hydroxyphenoxy acid)propionic acid to carry out etherification reaction. The quizalofop-p-ethyl prepared by the synthesis process disclosed by the invention is high in yield, the total ester content and the optical content of the quizalofop-p-ethyl reach 99%, and the purity of the quizalofop-p-ethyl is effectively improved.

The invention provides a method for refining acetylene, wherein a solvent is used for refining and removing impurities. The method is characterized in that the solvent is selected from one or more of liquid paraffin with the boiling range of 185-250 DEG C, distillate oil at vacuum side stream with the boiling range of 320-400 DEG C, distillate oil at second atmospheric side stream with the boiling range of 200-260 DEG C and distillate oil at first atmospheric side stream with the boiling range of 170-230 DEG C. The method provided by the invention is free from three-waste emission, and the DMY (dihydromyricetin) solvent in a solvent method can be recycled, so that the solvent is zero emission. The purity of recovered advanced alkyne is high and reaches over 99%, and the alkyne can be used as a fuel. The purity of acetylene purified is high, the content of impurities is lower than 0.05 %, and the loss of acetylene is low and is less than 0.5%.

The invention provides a method for preparing refined tellurium. The method comprises the following steps: dissolving crude tellurium dioxide in an acidic substance to obtain a dissolved matter; filtering the dissolved matter to obtain a solution and insoluble slag; taking the solution and a first reduction agent to react to removal impurities, so as to obtain an impurity-removed solution; takingthe impurity-removed solution to react with a second reduction agent; and filtering an obtained reaction product to obtain the refined tellurium. According to the method provided by the invention, theprepared product has high purity and a few of impurities; the method is simple and convenient to operate and the recovery rate of the tellurium is 99 percent or more; and the grade of the prepared tellurium product is 99.99 percent or more.

The invention provides a preparation method for p-hydroxy benzaldehyde. The preparation method comprises the following five steps: preparation of an intermediate I, preparation of an intermediate II,preparation of p-hydroxy benzaldehyde, impurity removal from a p-hydroxy benzaldehyde solution, and purification of the p-hydroxy benzaldehyde solution. The synthetic process is simple and standard, the production process and the production flow are easy to master, and the utilization ratio of a p-methylphenol raw material is improved effectively while the production operational standard of a p-hydroxy benzaldehyde product is improved effectively. By taking ammonia monohydrate as a reactant for the p-methylphenol raw material, the reaction on the p-methylphenol raw material is quicker and morecomplete, and ammonium sulfate impurity generated by the reaction is more easily treated. In the preparation process of the p-hydroxy benzaldehyde, a purification process on the p-hydroxy benzaldehyde is increased, so that the purity of the p-hydroxy benzaldehyde prepared can be improved effectively.