127 results about "Hydrogen bromide" patented technology

A process for producing propylene and hydrogen from propane, the process comprising the steps of: a) reacting a mixture comprising propane and bromine to produce a first reaction mixture comprising bromopropane and hydrogen bromide, b) subjecting the first reaction mixture obtained in step a) to at least one separation step to obtain a bromopropane-rich composition and to obtain a hydrogen bromide-rich composition, c) subjecting the bromopropane-rich composition obtained in step b) to a catalytic reaction to produce a second reaction mixture containing propylene and hydrogen bromide, d) subjecting the second reaction mixture obtained in step c) to at least one separation step to obtain a hydrogen bromide-rich composition and to obtain propylene, and e) subjecting the hydrogen bromide-rich composition obtained in step b) and / or the hydrogen bromide-rich composition obtained in step d) to electrolysis to obtain hydrogen and a bromine-containing composition, wherein preferably at least a portion of the bromine-containing composition is recycled back to step a).

The invention belongs to the technical field of fine chemical synthesis, belongs to a nonionic short fluorine chain surfactant, and relates to a preparation method of a fluorinated polyether surfactant. The preparation method comprises the following steps: reacting trimethylolethane with a hydrogen bromide acetic acid solution to prepare an intermediate 1; reacting the intermediate 1 in an alkaline environment without an organic solvent to prepare an intermediate 2; reacting the intermediate 2 with pentafluoropropanol under the action of potassium hydroxide and a catalyst 1 to prepare a fluorinated monomer; finally, the fluorinated monomer is subjected to ring opening polymerization under the action of an initiator and a catalyst 2, and the fluorinated polyether type surfactant is prepared. The method has the advantages of easily available raw materials, mild reaction conditions, simple synthesis, low cost, high yield and short fluorine chain of the product, can replace a long-chain fluorine-containing surfactant which is difficult to degrade, and can be used as an additive in the fields of photoresists, coatings, adhesives and the like. The surface tension can be obviously reduced, the surface defects of a coating can be reduced, and the appearance can be improved by adding a very small amount of the surface tension reducing agent.

The application discloses a high-purity electronic-grade hydrogen bromide metal ion impurity control device and a control method. The device comprises an adsorption column, a bag-type dust collector and a rectifying tower. First impurity removal mechanisms are arranged at the upper end of the adsorption column and the top of the rectifying tower to remove gas-phase metal impurities. Second impurity removal mechanisms are arranged at the tower kettle of the rectifying tower to remove liquid-phase metal impurities. The bag-type dust collector comprises a flow channel, a keel frame and dust removal bags. Third impurity removal mechanisms are arranged on the flow channel. The dust collector device of metal ions is added to the existing process system, and the structure is designed to realize solid-liquid separation of liquid to intercept metal particles. The structures of the adsorption equipment and the rectifying equipment are designed to remove gas-phase metal impurities and liquid-phase metal impurities, thereby increasing the removal efficiency and effect of metal particles.

The invention belongs to the technical field of medicinal chemistry, and relates to a novel small nucleic acid drug intermediate and a preparation method thereof, the intermediate is a 2 '-FANA-dU phosphoramidite monomer, the preparation method comprises the following steps: 1, reacting a compound a with a 33% hydrogen bromide-acetic acid solution in dichloromethane, and performing post-treatment to obtain a compound b; 2, reacting uracil and the like to generate a white solid, and reacting the white solid with the compound b to obtain a compound c; 3, reacting the compound c in methanol and ammonia water, crystallizing and drying to obtain a compound d; 4, the compound d reacts with 4, 4 '-dimethoxytriphenylchloromethane, and a compound e is obtained through treatment; 5, the compound e reacts with anhydrous diisopropyl imidazole and a 2-cyanoethyl-N, N, N ', N'-tetraisopropyl phosphoramidite reagent, and the 2 '-FANA-dU phosphoramidite monomer is obtained.The 2'-FANA-dU phosphoramidite monomer prepared through the method can modify siRNA, the biological activity of the siRNA can be reserved or even enhanced, and the biological stability of the siRNA can be remarkably improved.

This utility model belongs to the technical field of hydrogen bromide gas drying towers, specifically a hydrogen bromide gas drying tower with replaceable packing, including a drying tower body, a protective net, and an installation mechanism. The protective net is installed on the outer wall of the drying tower body. The installation mechanism includes an installation shell, filter plates, and a fixing shell. The installation shell is located inside the drying tower body; an installation groove is formed on the inner wall of the installation shell; the filter plates are respectively installed inside the corresponding installation grooves; and the fixing shell is located inside the installation shell. This utility model places the fixing shell inside the installation shell, and then installs the filter plates into the corresponding installation grooves. A partition plate can divide the interior of the installation shell into multiple independent spaces for replacing and classifying different types of packing.

The present invention relates to the field of production wastewater oxidation recovery, and specifically to a production wastewater oxidation recovery device, comprising an evaporation box, an evaporation assembly being provided in the evaporation box, and a condensation assembly being provided at an upper port of the evaporation box; the evaporation assembly comprising a rotating shaft horizontally arranged across the evaporation box, a wheel body being coaxially fixedly connected to the middle position of the rotating shaft, and a plurality of arc-shaped evaporation plates being provided on the surface of the wheel body; in the present invention, the wheel body is designed to stir hydrogen bromide wastewater and an oxidant, hydrogen peroxide, continuously during rotation, thereby ensuring full contact between the oxidant and the wastewater and improving the oxidation reaction efficiency of the hydrogen bromide and hydrogen peroxide; and simultaneously, as the wheel body continuously rotates, each evaporation plate can be continuously rotated out of the mixed liquid. After being carried out, the evaporation plate can quickly heat and evaporate the elemental bromine solution on the evaporation plate, thereby significantly improving the evaporation effect.

The invention relates to the technical field of preparation of fluorine-containing organic intermediates, in particular to a method for preparing 2-bromoheptafluoropropane through photothermal conversion. The method comprises the following steps: respectively vaporizing, mixing and preheating heptafluoropropane and bromine, introducing into a photo-thermal reactor, carrying out bromination reaction to obtain mixed gas containing 2-bromoheptafluoropropane, introducing the mixed gas containing 2-bromoheptafluoropropane into a fluorine removal device containing silicon dioxide, carrying out fluorine removal reaction, washing with water, carrying out alkali washing, dehydrating, compressing, condensing, carrying out two-stage rectification, and drying to obtain 2-bromoheptafluoropropane. The high-purity 2-bromoheptafluoropropane is obtained. According to the method, hydrogen fluoride is removed from the mixed gas containing 2-bromoheptafluoropropane through a fluorine removal reaction, hydrogen bromide is removed through water washing, alkali washing and dehydration, impurities are removed through secondary rectification, finally, the high-purity 2-bromoheptafluoropropane product is obtained through drying and dehydration, and the purity of the product is up to 99.91-99.98%.

The application belongs to the technical field of fine chemical industry, and particularly relates to a hydrogen bromide purification method for removing bromine, water and impurities before liquefaction, which comprises the following steps: S1, removal of free bromine: hydrogen bromide gas is introduced into a first bromine removal tank filled with a red phosphorus filler layer; S2, preliminary removal of water: the gas treated in S1 is introduced into a first drying tank filled with liquid phosphorus tribromide; S3, deep removal of trace water: the gas treated in S2 is introduced into a second drying tank filled with resin or mordenite; and S4, separation of mechanical impurities: the gas treated in S3 is introduced into a cyclone separator. By adopting the red phosphorus filler layer and controlling the loading amount, particle size and loading density of the red phosphorus, the free bromine in the hydrogen bromide gas can be efficiently removed, liquid phosphorus tribromide is used as a drying medium and is supplemented in real time to maintain the mass concentration of the phosphorus tribromide, so that the bromine and water content in the gas can be effectively reduced, and high-quality gas is provided for subsequent deep drying and impurity separation.

The application provides a synthesis method of 6-bromo-2-chloro-3-nitropyridine and relates to the technical field of organic synthesis. 2-amino-3-nitro-6-chloropyridine is reacted with a hydrobromic acid acetic acid solution to obtain 2-amino-3-nitro-6-bromopyridine, which is diazotized to obtain 6-bromo-2-hydroxy-3-nitropyridine, and then the 6-bromo-2-hydroxy-3-nitropyridine is reacted with a chlorinating reagent to obtain 6-bromo-2-chloro-3-nitropyridine. The synthesis method of 6-bromo-2-chloro-3-nitropyridine has the advantages of easy availability of raw materials, low price, mild reaction condition, simple process, high economic benefit, suitability for large-scale production, and the like, can solve the current situation of high price of 6-bromo-2-chloro-3-nitropyridine, and can play a positive role in the promotion of downstream products of 6-bromo-2-chloro-3-nitropyridine.

The present invention discloses a method for determining chloride ions in electronic grade hydrogen bromide by ion chromatography, comprising the following steps: (1) preparing and analyzing Cl ‑ Standard solution, obtain the working curve of concentration and peak area; (2) Pretreatment of hydrogen bromide sample: connect three washing bottles in series on the hydrogen bromide sampling tube, the first one is a buffer bottle, the second and third ones are absorption bottles filled with 100mL high-purity water, after absorption, combine the obtained hydrogen bromide absorption solution; (3) add alkali solution to adjust the pH value of hydrogen bromide solution to 4-10, and make up the volume with a volumetric flask to prepare the solution to be tested; (4) use ion chromatograph to detect the solution to be tested and obtain the trace amount of Cl in electronic grade hydrogen bromide ‑ The chromatogram of the test was obtained, and the Cl in the test solution was detected according to the external standard method. ‑ Quantitatively obtain Cl in electronic grade hydrogen bromide ‑ The method is simple to operate, has good reproducibility and high sensitivity.

The utility model relates to the technical field of hydrogen bromide purification, and discloses an electronic-grade hydrogen bromide purification device which comprises a settling tank, a rotary feeding mechanism is arranged on the settling tank, and a waste gas discharge mechanism is arranged at the top of the settling tank; the rotary feeding mechanism comprises a supporting seat, the supporting seat is fixedly mounted at the top of the settling tank, a fixed pipeline is fixedly mounted on the inner wall of the supporting seat, and a first valve pipe is fixedly connected to the top of the fixed pipeline. Through the overall design of a rotary introduction mechanism, ozone can be introduced from a first valve pipe, the ozone can penetrate through a rotary pipeline to be output from the end of a branch pipeline, meanwhile, through work of a driving motor, the rotary pipeline can be driven to rotate integrally, so that the ozone is rotationally introduced into a stock solution, and meanwhile, a stirring paddle can be driven to rotate; the stirring paddle can stir the stock solution, so that the contact effect of the stock solution and the ozone is further improved, the utilization rate of the ozone is improved, and the consumption of the ozone is reduced.

The invention relates to the technical field of electronic gas purification, in particular to silicon-oxygen-silicon-containing polydivinylbenzene and a preparation method and application thereof, and the silicon-oxygen-silicon-containing polydivinylbenzene comprises a polydivinylbenzene skeleton; a silicon-oxygen-silicon bond is chemically bonded on the polydivinylbenzene skeleton. The silicon-oxygen-silicon-containing polydivinylbenzene is prepared by adopting an in-situ synthesis method, the silicon-oxygen-silicon-containing polydivinylbenzene reacts with the dry hydrogen bromide gas to obtain the silicon-bromine bond-containing polydivinylbenzene, and the water content in the hydrogen bromide gas can be reduced through hydrolysis reaction. The silicon-oxygen-silicon-containing polydivinylbenzene has stable properties, is environment-friendly in the preparation and transfer processes and the use process of the silicon-oxygen-silicon-containing polydivinylbenzene as a water removal material, does not introduce metal impurities, and has a good water removal effect.

The invention discloses low-defect few-layer graphene water-based conductive paste and a preparation method and application thereof, and belongs to the technical field of conductive paste. The low-defect few-layer graphene water-based conductive paste comprises the following components in parts by weight: 1-3 parts by mass of low-defect few-layer graphene, 100 parts by mass of ultrapure water and 0.8-1.2 parts by mass of a conductive additive, the low-defect few-layer graphene is obtained by performing room-temperature intercalation on graphite powder, performing chemical expansion and performing water-phase stripping by adopting an aqueous solution of 5 '-adenine nucleotide salt, the conductive additive is amphiphilic polythiophene; the amphiphilic polythiophene is obtained by polymerizing 2, 5-dibromo-3-triethylene glycol monomethyl ether thiophene and 3-[10-(4-toluene ether) decyl] thiophene which are used as monomers and then treating by hydrogen bromide and anhydrous acetic anhydride; the low-defect few-layer graphene water-based conductive paste prepared by the invention has few graphene defects, good dispersity and excellent conductivity.

The application discloses a high-temperature-resistant metalized capacitor film and a preparation method thereof, and belongs to the technical field of thin film or thick film capacitors. The application provides a novel method for preparing a metalized capacitor film, which comprises the following steps: taking 4-vinylbenzocyclobutene as raw material, and combining the raw material with hydrogen bromide after an addition reaction to obtain a substitution product; combining 2-methoxy-4-vinylphenol with the substitution product after demethylation to obtain a polymerization monomer containing a double bond and a cycloalkane structure; polymerizing the polymerization monomer with decafluorobiphenyl and 4-allylphenol to obtain a base film; and plating a metal layer on the base film to obtain the high-temperature-resistant metalized capacitor film. The application has good thermal stability, and solves the technical problem that a thermoplastic base film is deformed or decomposed at high temperature, and is difficult to meet the use requirement.

The invention relates to the technical field of biomass organophosphorus flame-retardant environment-friendly amino resin adhesive synthesis, and discloses a biomass organophosphorus flame-retardant environment-friendly amino resin adhesive synthesis method, which comprises: drying an agricultural waste biomass raw material until the water content is less than or equal to 5%, crushing, and screening with a 80-120 mesh sieve to obtain biomass powder. According to the synthesis method of the biomass organophosphorus flame-retardant environment-friendly amino resin adhesive, a phosphorus-carbon synergistic flame-retardant system is constructed through biomass (agricultural wastes) and organophosphorus, and the oxygen index of the adhesive can be increased to be greater than or equal to 33.5% (far greater than 22% of pure amino resin and 30% of an inorganic flame retardant) without high addition amount; meanwhile, hydroxyl groups and carboxyl groups in the biomass and a resin matrix form hydrogen bonds, so that 30%-40% of bonding strength reduction caused by agglomeration of a traditional inorganic flame retardant is effectively avoided, and the normal bonding strength of the product is ensured to be greater than or equal to 1.9 MPa; and halogen flame retardants are abandoned, so that no toxic gases such as hydrogen bromide and dioxin are released during combustion.

The application provides a preparation method of high-content 2-trifluoromethyl-4-heptafluoroisopropylaniline, in which 2-trifluoromethyl aniline and 2-bromine heptafluoropropane are reacted in the presence of hydrosulfite, a solvent and a catalyst to obtain high-content 2-trifluoromethyl-4-heptafluoroisopropylaniline through reaction and post-treatment; the catalyst is selected from phosphoric acid, pyrophosphoric acid, hypophosphorous acid, metaphosphoric acid, phosphorous acid, pyrophosphorous acid, hydrobromic acid, hydrogen bromide gas, hydrogen chloride gas or sodium bisulfite. The preparation method is simple in operation and mild in chemical reaction conditions; under the preferred reaction conditions, the conversion content reaches more than 96% in one reaction, the post-treatment steps are few, rectification is not needed, the content of the final product is more than 98%, the total reaction yield is more than 93%, the industrial production is easy, and the method has a high application prospect.

The present invention relates to a process for producing carbon comprising the step of exothermically pyrolyzing a starting composition containing at least 50% by mole of dibromomethane, less than 5% by mole of hydrogen donor and less than 0.5% by mole of oxygen in a pyrolysis reactor at a temperature of 600 to 2,000°C to carbon and hydrogen bromide.

This invention relates to a flame-retardant acrylic fabric and its preparation method. The fabric is characterized by being prepared by the following method: First, chloropropyl-POSS is reacted with melamine to obtain a substituted product; the substituted product is reacted with an aqueous solution of hydrogen bromide to obtain a modified solution; finally, the acrylic fabric is immersed in the diluted solution for finishing, thus obtaining the flame-retardant acrylic fabric. The flame-retardant acrylic fabric prepared by this invention has an initial limiting oxygen index (LOI) of over 34%, falling within the range of flame-retardant materials; after five washes, its LIO does not decrease significantly, remaining above 31%.

The invention discloses a preparation method of a 4-(allyl)-4-methyl-1, 1 '-biphenyl liquid crystal monomer, which comprises the following steps: S1, by taking p-phenylboronic acid, dechlorobenzyl alcohol, Pd / Cl and sodium carbonate as raw materials, reacting for 1-12 hours in a toluene and water system under the protection of nitrogen to obtain 4'-methyl-[1, 1 '-biphenyl]-4-benzyl alcohol (intermediate 1); s2, taking the intermediate 1 and hydrochloric acid as raw materials, and petroleum ether, toluene or ethanol as a solvent to obtain 3-(chloromethyl)-4 '-methyl-1, 1'-biphenyl (intermediate 2); s3, finally, chloropropene, the intermediate 2, magnesium particles and dibromoethane are used as raw materials, and tetrahydrofuran, petroleum ether or methylbenzene is used as a solvent; according to the present invention, the target compound is synthesized by using the existing raw materials and the technical equipment, such that the use amount of the catalyst is small, the catalytic efficiency is high, and compared with the hydrogen bromide, the corrosion on the equipment is weak, the conversion rate is high, the yield is high, the post-treatment process is simple, and the cost is reduced and the effect is improved.

The present application provides a hydrogen bromide hydrogenated nitrile rubber raw material composition, hydrogen bromide hydrogenated nitrile rubber and a preparation method thereof. The hydrogen bromide hydrogenated nitrile rubber raw material composition comprises a first component and a second component; the first component comprises acrylonitrile and butadiene monomers; and the second component comprises a functional monomer. The functional monomer can introduce bromine atoms, hydroxyl groups, ether groups and long-chain alkyl groups into the molecular chain of the hydrogenated nitrile rubber in a macromolecular form, so that the hydrogen bromide hydrogenated nitrile rubber obtained by polymerization has good low-temperature resistance and vulcanization speed.

The application discloses a device and method for treating flue gas, which comprises a urea supply device, a flue gas pipeline, a cooling device, a dust removal device, a denitration device and an absorption device, wherein the urea supply device is provided with a urea outlet, the flue gas pipeline is provided with a high-temperature flue gas inlet, a urea inlet and a mixed flue gas outlet, the urea inlet is connected with the urea outlet, the cooling device is provided with a mixed flue gas inlet, a cooled flue gas outlet and a cooling medium inlet, the mixed flue gas inlet is connected with the mixed flue gas outlet, the dust removal device is provided with a cooled flue gas inlet and a dust-removed flue gas outlet, the cooled flue gas inlet is connected with the cooled flue gas outlet, the denitration device is provided with a dust-removed flue gas inlet and a denitration flue gas outlet, the dust-removed flue gas inlet is connected with the dust-removed flue gas outlet, and the absorption device is provided with a denitration flue gas inlet and a purified flue gas outlet. The device can be used for treating flue gas containing nitrogen oxides, bromine and / or hydrogen bromide, and the water consumption and treatment cost can be reduced.

The application is suitable for the technical field of inorganic substance preparation method, and provides a preparation method of bromine, which comprises the following steps: step one: a certain amount of sodium bromide and hydrobromic acid are added into a mother liquor pool and stirred to obtain a mother liquor; step two: a predetermined amount of stearic acid and polyvinylpyrrolidone are added; step three: preheating is carried out, and then the preheating is fed into an absorption tower; step four: the liquid at the bottom of the absorption tower flows into the upper part of a bromine evaporation tower, and is heated by steam in the bromine evaporation tower; water vapor and chlorine gas are introduced from the bottom of the bromine evaporation tower, and bromine steam enters the absorption tower; step five: the distillation acid liquid generated by the bromine evaporation tower flows into a preheater to be preheated; bromine steam flows out from the upper part of the bromine evaporation tower to obtain a bromine and water mixture; step six: the bromine and water mixture flows into a bromine water separation bottle to be separated, and bromine products are obtained, thereby, the bromine source is hydrogen bromide and sodium bromide; the stearic acid can effectively reduce the surface tension, so that the reaction is more uniform, and the system is stable.

The invention discloses brominated polystyrene with high thermal stability and a preparation method thereof. The brominated polystyrene is novel brominated polystyrene with high thermal stability formed by adding a substance with a special structure into prepared brominated polystyrene and uniformly mixing. By introducing a special structure substance, a small amount of bromine-containing micromolecules which can trigger the decomposition of brominated polystyrene and are contained in the brominated polystyrene can be reacted and absorbed at a relatively high temperature, so that the accelerated decomposition reaction of the brominated polystyrene caused by the bromine-containing micromolecules is inhibited; in addition, the introduced special structure can absorb hydrogen bromide and other unstable bromine-containing small molecules released by the brominated polystyrene at the initial stage of thermal decomposition of the brominated polystyrene, so that the decomposition temperature of the brominated polystyrene is further increased. The brominated polystyrene with high thermal stability has the advantages of light product color, good mechanical properties of nylon materials and the like when being applied to flame-retardant nylon compounds, especially special nylon.

This invention provides a method for preparing pyrrolidine derivatives, belonging to the field of organic synthesis. The method comprises the following steps: Step 1, reacting compound 1 in the presence of an alkaline ester hydrolysis reagent to obtain compound 2; Step 2, adding compound 2 to an aqueous solution of hydrogen bromide, followed by the addition of sodium nitrite to react and obtain compound 3; Step 3, reacting compound 3 in the presence of a dehalogenating reducing agent to obtain compound 4; Step 4, reacting compound 4 in the presence of a carbonyl reducing agent to obtain compound 5. The preparation method provided by this invention enables the industrial production of compound 5 and its derivatives.

The invention discloses a 2, 6-diethyl-4-methyl bromobenzene full-continuous flow synthesis process and a reaction device thereof, and relates to the technical field of compound synthesis. A reaction substrate and a sodium nitrite solution mixed with a catalyst are respectively input into a full-continuous flow shear reaction device through a feed port; after flowing through the temperature zone 1, the mixture is mixed with hydrobromic acid and enters a temperature zone 2 to complete a diazotization reaction, a diazotization reaction solution is obtained, the diazotization reaction solution flows out of the temperature zone 2, enters the bromination unit, reacts with a bromination reagent in the bromination unit, sequentially flows through a temperature zone 3 and is output from a discharge port, and a final product 2 is obtained after extraction, water washing, desolvation and distillation. The catalyst is 2, 6-diethyl-4-methyl bromobenzene. A continuous process is adopted, so that the difficulty of industrial application is greatly reduced; and during industrial amplification, the required production scale can be obtained through one-time amplification without tedious and complex multi-time step-by-step amplification and adjustment and optimization of process conditions and parameters, so that manpower, material resources and project development time are greatly saved.

The invention discloses a production method and a production system of hydrogen bromide, and belongs to the technical field of electronic special gas preparation. A hydrobromic acid liquid raw material is conveyed to a first-stage rectifying tower, a first-stage tower substrate is conveyed to a second-stage rectifying tower, a second-stage tower substrate flows back to the first-stage rectifying tower, a first-stage tower top substance is conveyed to an adsorption column, and an adsorbed hydrogen bromide product is collected. Wherein the tower bottom temperature of the first-stage rectifying tower is 150-180 DEG C, the tower top temperature of the first-stage rectifying tower is-40--20 DEG C, the tower pressure of the first-stage rectifying tower is 250-750 kPa, the tower bottom temperature of the second-stage rectifying tower is 85-95 DEG C, the tower top temperature of the second-stage rectifying tower is 45-75 DEG C, and the tower pressure of the second-stage rectifying tower is 10-40 kPa. By adopting the multi-stage pressure swing distillation and adsorption dehydration under the parameter conditions, the high-purity hydrogen bromide product can be prepared, and the yield can be improved.

The invention belongs to the technical field of high polymer materials, and particularly relates to a preparation process of a high-impact-resistance flame-retardant PBT / ABS composite material. Comprising the following steps: preparing a flame-retardant impact-resistant rubber reinforcing agent; compounding a flame-retardant impact-resistant rubber reinforcing agent to prepare ABS resin; separating and recombining free chain segments and compounding the material. The preparation method comprises the following steps: adding 3-bromopropyltrimethoxysilane into a hydrogen bromide aqueous solution and absolute methanol, carrying out a water-bath heating reaction to prepare an octabromo cage type coupling agent with a hexahedral structure, and then controlling the mass ratio of the octabromo cage type coupling agent to butadiene to be 45: (6-8) to prepare the flame-retardant and impact-resistant rubber reinforcing agent containing a multi-arm polybutadiene structure and a Br group. In the preparation process of the ABS resin, the ABS resin is endowed with high impact resistance and tensile strength, and is endowed with high flame retardancy without influencing the physical properties, and the PBT / ABS composite material can also have good flame retardancy without additionally adding a flame retardant during the subsequent preparation of the PBT / ABS composite material.

The invention provides a method for preparing rubidium halide / cesium halide based on lithium precipitation mother liquor, which comprises the following steps: adding a first extraction agent into the lithium precipitation mother liquor, and mixing and extracting to obtain a cesium-loaded organic phase and cesium extraction raffinate; mixing the cesium-loaded organic phase with a first detergent, and washing to obtain a washed cesium-loaded organic phase; the washing cesium-loaded organic matter and a first stripping agent are mixed for countercurrent stripping, cesium-rich stripping liquid is obtained, and the stripping agent is a hydrogen bromide or hydrogen iodide aqueous solution; the cesium-rich strip liquor is subjected to oil removal, evaporation and crystallization, and a cesium halide product is obtained; roasting the cesium halide product to obtain white cesium halide powder; performing counter-current extraction on the cesium extraction raffinate to obtain a rubidium-loaded organic phase; carrying out countercurrent washing on the rubidium-loaded organic phase and a second detergent to obtain a washed rubidium-loaded organic phase; the washing rubidium-loaded organic phase and a second stripping agent solution are subjected to countercurrent stripping, and rubidium-rich stripping liquid is obtained; and deoiling, evaporating, crystallizing and calcining the rubidium-rich strip liquor to obtain a rubidium halide product.

This invention relates to the field of acyclic or carbocyclic compounds and discloses a method for preparing 6-bromo-2,3-difluorotrifluorotoluene, comprising: dissolving 2,3-difluorotrifluorotoluene in a mixed solvent composed of a polar modifier containing a proton acceptor site and a nonpolar solvent; adding a polyether stabilizer and an iron-based catalyst; and dropwise adding liquid bromine to trigger a directional bromination reaction. The method utilizes the protonated ion-pair complex formed by the in-situ generation of hydrogen bromide and the polar modifier, which, in conjunction with the polyether stabilizer, constructs a sterically hindered shielding structure at positions 4 and 5 of the substrate molecule. This invention forces the electrophilic substitution pathway to be directed towards position 6 of the substrate molecule, overcoming the bottleneck of extremely low positioning accuracy in passivated aromatic ring systems, transforming disordered isomers into a single dominant isomer, thereby reducing separation energy consumption.

This invention discloses a microwave-assisted synthesis process for 11-bromoundecenoic acid. The specific steps are as follows: undecenoic acid is mixed with a nonpolar solvent, an initiator is added, and the mixture is stirred. The resulting preliminary reaction mixture is then transferred to a microwave reactor. After adjusting the microwave power and controlling the temperature, the mixed solution undergoes an anti-Markovnikov addition reaction with hydrogen bromide gas within the microwave reactor to generate a bromoundecenoic acid solution. The resulting addition solution is then transferred to a crystallization vessel for freeze crystallization. The crystallized product is filtered to obtain 11-bromoundecenoic acid. This invention utilizes hydrogen bromide aeration and mechanical stirring in the microwave reactor to increase the gas-liquid mass transfer area and improve mass transfer efficiency. The microwave-assisted synthesis of 11-bromoundecenoic acid achieves molecular-level stirring, significantly shortening the reaction time and effectively increasing the yield of the target product. Simultaneously, the use of a nonpolar solvent with weak microwave absorption effectively avoids the thermal effect generated by microwaves, resulting in an even higher yield of the target product.