41 results about "O-Xylene" patented technology

The application discloses a synthesis method of 2,3,3',4'-biphenyl tetracarboxylic dianhydride, characterized in that 2,3-dimethylaniline is used as a starting raw material, 2,3-dimethylaniline diazonium salt is prepared through a diazotization reaction, then 2,3,3',4'-tetramethyl biphenyl is prepared through a coupling reaction of the 2,3-dimethylaniline diazonium salt and o-xylene under the catalysis of cuprous chloride, and finally 2,3,3',4'-biphenyl tetracarboxylic dianhydride is prepared through an oxidation reaction and dehydration to form anhydride. The coupling reaction in the synthesis method has good selectivity, 3,3,4',4'-tetramethyl biphenyl which is difficult to separate is not generated, high-purity a-BPDA can be finally obtained, and the coupling reaction in the synthesis method only needs to use low-cost cuprous chloride as a catalyst, so that the production cost is greatly reduced compared to a high-cost catalytic system in the prior art, and the synthesis method is more suitable for industrial mass production.

The application provides a catalyst and a preparation method and application thereof, and the catalyst comprises a carrier and an active metal component loaded thereon; the carrier comprises ZSM-5 zeolite and a binder, and the molar ratio of SiO2 / Al2O3 in the ZSM-5 zeolite is 15-50; the amount of strong acid centers on the outer surface of the catalyst is less than or equal to 10 mu mol / g; and the ratio of the saturated adsorption amount of p-xylene to the saturated adsorption amount of o-xylene of the catalyst is 3-20 under the condition of 400 DEG C. The catalyst provided by the application can catalyze the generation of benzene from toluene dealkylation under a medium-temperature condition, and the selectivity of benzene is good and the yield is high.

The invention discloses a microwave crystallization preparation method of a transition metal nitride ultrathin nanosheet, which comprises the following steps: (1) dissolving a transition metal salt and Li3N in an o-xylene solution, then adding an ethylenediamine solution, fully stirring, heating the solution, and carrying out microwave crystallization to obtain a precursor solution; and carrying out centrifugal collection, washing and vacuum drying to obtain the amorphous transition metal nitride nanosheet. The transition metal salt is WCl < 6 >, VCl < 3 > or MoCl < 5 >; and (2) in a nitrogen atmosphere, the amorphous transition metal nitride nanosheet is subjected to rapid microwave heating, and the highly crystallized transition metal nitride nanosheet is obtained. The preparation process of the TMN nanosheet with the surface-enhanced Raman effect, provided by the invention, has very strong controllability, the thickness of the prepared nanosheet is about 1-2nm, the phenomenon of sintering or aggregation is avoided, and the TMN nanosheet with the surface-enhanced Raman effect has an outstanding surface-enhanced Raman spectrum effect.

The invention discloses a covalent organic framework material for directly capturing carbon dioxide in air and coupling solar photo-thermal rapid desorption and a preparation method of the covalent organic framework material, and belongs to the field of materials. According to the material, piperazine with secondary amine sites and dialdehyde derivatives are used as raw materials, dioxane and mesitylene, m-xylene and mesitylene or o-xylene and mesitylene are used as solvents, and solvothermal reaction is performed; and after the reaction is finished, sequentially carrying out suction filtration and washing by using DMF and THF, carrying out Soxhlet extraction for 24 hours, and then carrying out vacuum drying to obtain the covalent organic framework. The aldehyde and the secondary amine are condensed according to the proportion of 1: 2, and the secondary amine site of the raw material piperazine is converted into the tertiary amine site in the covalent organic framework through aminal reaction. Tertiary amine nitrogen atoms can specifically recognize carbon dioxide in air and perform chemical adsorption, and firm covalent bonds can ensure the stability of a covalent organic framework, so that efficient air carbon dioxide capture is realized. In addition, ionic bonds formed by the covalent organic framework and carbon dioxide are also beneficial to coupling solar photo-thermal low-energy-consumption desorption.

The invention discloses a preparation method of high-molecular-weight polyvinyl ether, and relates to the technical field of organic synthesis. Comprising the following steps: 1, adding vinyl ethyl ether into o-xylene, and adding alcohol and a catalyst to initiate polymerization; and 2, carrying out low-temperature polymerization, after the reaction is finished, adding deionized water, carrying out liquid separation and distillation, and adding o-xylene to adjust the solid content so as to form a solution, thereby obtaining the high-molecular-weight polyvinyl ether. Vinyl ethyl ether is dissolved in o-xylene, a catalyst is added at the temperature of 30-40 DEG C to initiate a polymerization reaction, polymerization continues at the temperature of-10-10 DEG C, and light yellow transparent viscous liquid, namely the high-molecular-weight polyvinyl ethyl ether, is obtained. The method is carried out in the solvent, the solvent does not need to be removed and recycled, the reaction route operation is simple, and the polymer molecular weight is controllable. The method has the advantages of no by-product and high yield.

The invention provides an organic solar cell device prepared through electric field assisted solution shear coating and a preparation method, and belongs to the technical field of organic photovoltaic device preparation. An organic solar active layer based on a non-fullerene receptor is selected, and a halogen-free solvent o-xylene is adopted; in the active layer film deposition process, an external pulse polarization electric field is applied to control molecular arrangement and microcrystal morphology, so that the photoelectric conversion efficiency of an organic photovoltaic device without extra thermal annealing is improved. The preparation process of the organic solar cell is simplified, the method has wide commercial application prospects, and a detailed solution is provided for commercialization of the organic solar cell.

This invention discloses an ultra-low friction lubricating material system with self-catalytic effect and its preparation method, belonging to the field of lubricant technology. The ultra-low friction lubricating material system is composed of a base oil, an organometallic catalyst, and organic additives. The organometallic catalyst is at least one selected from ferrocene, cobalt carbonate, cobalt oxalate, copper acetate, and nickel oxalate. The organic additives are at least one selected from o-xylene, ethylene glycol, dodecanol, oleic acid, and tetraethyl orthosilicate. During friction, the organometallic catalyst releases metal ions, which, under the action of frictional heat and contact pressure, catalyze the base oil components to form a carbonaceous lubricating film in situ on the surface of the friction pair. The organic additives provide an additional carbon source during friction, working together with the organometallic catalyst to reduce the break-in time for the friction pair to reach a stable state. This lubricating material system not only significantly reduces the coefficient of friction and wear rate but also significantly shortens the break-in time.

The application discloses a network soil thermal desorption catalyst, a preparation method and application thereof, and belongs to the field of environmental protection. The catalyst takes an iron net as a carrier and takes manganese-cobalt composite metal sulfide as an active component. The mass content of the active component is 3-6% based on the mass of the carrier. The scheme is characterized in that the iron net is subjected to oxidation pretreatment, so that an iron trioxide oxidation layer is formed on the surface; then the iron net is immersed in an active component solution to perform electrochemical deposition loading; finally, the finished catalyst is formed through special atmosphere calcination. The catalyst is environment-friendly, can efficiently induce the thermal desorption of organic pollutants in soil, and can realize 100% removal of o-xylene at 120 DEG C. Meanwhile, the catalyst is convenient to recycle, has higher economic benefits and wide market application prospect.

The application discloses a synthesis method of o-phthalaldehyde. O-xylene, a halogenated reagent and an organic solvent are mixed, and under ultraviolet light irradiation, a bromination product with different bromination degrees is generated by reaction; water is added into the reaction liquid, and the reaction is continuously carried out; after the reaction is completed, the organic solvent and water are removed by evaporation, and a crude ɑ, ɑ, ɑ', ɑ'-tetra-brominated o-xylene product is obtained; the crude product is recrystallized to obtain ɑ, ɑ, ɑ', ɑ'-tetra-brominated o-xylene product; and the ɑ, ɑ, ɑ', ɑ'-tetra-brominated o-xylene is hydrolyzed to obtain o-phthalaldehyde. The synthesis method optimizes the bromination and hydrolysis process, and by adding appropriate water in the o-xylene bromination process, the yield of the final product o-phthalaldehyde is improved.

The application discloses a kind of fast screening method of solvent residual quantity in food contact packaging material, sample is sent into gas chromatograph by headspace sampler and separates out the gas to be measured, and the gas to be measured is detected using hydrogen flame ion detector, and the chromatogram of sample is obtained;Add mixed standard intermediate liquid of known content in blank matrix to obtain the standard reference sample of the limited concentration to be measured, and the peak area of methyl acetate, benzene, toluene, ethylbenzene, o-xylene, m-xylene, p-xylene is measured respectively;By comparing the sum of the peak area of all detected substances in sample chromatogram with the chromatographic peak area of methyl acetate in standard reference sample, judge whether the total amount of residual solvent meets the limit requirement, and by comparing the peak area of benzene, toluene, ethylbenzene, o-xylene, m-xylene, p-xylene in sample with the peak area of corresponding substance in standard reference sample, judge whether each benzene solvent meets the limit requirement.

The invention discloses a method for preparing 9, 9-bis (3, 4-dicarboxyphenyl) fluorene dianhydride, which specifically comprises the following steps: S1, adding 9-fluorenone and o-xylene into a reaction kettle; S2, adding sulfuric acid and stirring; s3, cleaning is conducted; s4, preparing an intermediate 1; s5, stirring the raw materials until the raw materials are dissolved and clarified, cooling to room temperature without solid precipitation, and transferring to a continuous flow section; s6, carrying out continuous flow reaction treatment; and S7, adding acetic anhydride, filtering, and drying to obtain the 9, 9-bis (3, 4-dicarboxyphenyl) fluorene dianhydride. The invention relates to the technical field of catalyst preparation. According to the method for preparing 9, 9-bis (3, 4-dicarboxyphenyl) fluorene dianhydride, a continuous flow SK mixer is adopted to more fully realize gas-liquid mixing, so that the reaction rate is increased, the area of a continuous flow reaction unit is small, the risk in the industrialization process is reduced, continuous production is realized, and the problems of high safety risk, low productivity and the like of an intermittent reaction kettle are solved.

The invention discloses a centrifugal blowing control system and a control method for preparing phthalic anhydride by oxidizing o-xylene. The centrifugal blowing control system comprises a microcontroller, an oxidation fan arranged on one side of an air inlet of the oxidation reactor, a mass flow meter arranged on one side of a material inlet of the oxidation reactor, a reaction product monitor arranged on one side of a material outlet of the oxidation reactor, and a temperature sensor arranged in the oxidation reactor; the control method comprises the steps that oxidation reaction parameters are detected in real time, and a dynamic interlocking model between the current air outlet volumes of the oxidation fans is established based on the feeding amount and the reaction product concentration; and recalculating the required current air outlet volume according to the dynamic interlocking model, and adjusting the rotation frequency of the oxidation fan according to the current air outlet volume. According to the method, multi-parameter cooperative regulation and control are achieved, accurate air volume adaptation is achieved, manual valve adjustment is reduced, the workload is reduced, meanwhile, the process matching performance is improved, the energy consumption of the system can be effectively reduced, the production cost is reduced, and the phthalic anhydride yield is increased.

The application discloses a kind of twin ZSM-5 molecular sieve and synthesis method thereof, belong to inorganic chemistry technical field.The twin ZSM-5 molecular sieve is covered by the (010) crystal surface of one coffin-shaped ZSM-5 to the (100) crystal surface of another coffin-shaped ZSM-5, so that the molecular sieve surface has higher straight channel exposure ratio.Preparation process includes: (i) water, sodium hydroxide, aluminum source, template agent, silicon source are mixed and stirred to obtain synthesis gel A;(ii) three kinds of molecular sieves MCM-35, MOR, MCM-22 are added to alkaline environment according to the ratio of 1:2:4, and alkaline heat treatment is carried out to obtain mixture B containing "mfi, mor, mel" three kinds of structural units;(iii) A, B are mixed according to the water content of 1:1, and ZSM-5 molecular sieve product is obtained by hydrothermal crystallization.For the "primary aromatic hydrocarbon mixture" obtained after benzene, toluene, p-xylene are separated from the aromatic hydrocarbon mixture obtained by petroleum and non-petroleum route, twin ZSM-5 molecular sieve shows enhanced selectivity to o-xylene and m-xylene due to higher "straight channel exposure ratio" on the surface.

The invention provides a large-area photovoltaic device PTAA hole transport layer and a preparation method thereof, and a perovskite cell, and the preparation method comprises the steps: dissolving PTAA in a green solvent of o-xylene and / or anisole, and forming a precursor solution with the concentration of 0.75-3 mg / mL; depositing on the surface of a substrate through a solution method process; then vacuum auxiliary deposition is carried out, and standing is carried out for 10-90 s under the vacuum degree of 10-100 Pa so as to precisely regulate and control solvent volatilization; and finally, annealing for 5-30 minutes at the temperature of 100-130 DEG C to obtain the PTAA hole transport layer. Through the synergistic effect of the green solvent system and the vacuum-assisted deposition process, the uniformity and compactness of the PTAA film layer on the large-area substrate are remarkably improved, and the defects of strips, water stains and the like are effectively eliminated; when the material is applied to a perovskite battery, upper perovskite can be induced to form a high-quality thin film, interface defects are reduced, and non-radiative recombination is inhibited.

A feed mixture comprising one or more xylene isomers and C9+ aromatic hydrocarbons may be separated in a first distillation column to obtain a first overhead stream comprising m-xylene and / or p-xylene and a first bottoms stream comprising o-xylene and C9+ aromatic hydrocarbons. The first bottoms stream may be optionally isomerized through liquid-phase isomerization and fed to a second distillation column to obtain a second overhead stream comprising at least o-xylene and a second bottoms stream comprising C9+ aromatic hydrocarbons. The second overhead stream may be optionally isomerized through liquid-phase isomerization. Liquid-phase isomerization may occur upon at least one of the first bottoms stream, the second overhead stream, an optional side stream obtained from the first or second distillation columns, or within the first or second distillation columns, such that the second overhead stream or an isomerized second overhead stream is rich in p-xylene.

The utility model belongs to the field of tetrachloro-o-xylene manufacturing equipment, and particularly relates to a power-adjustable light source generator device for tetrachloro-o-xylene production, which comprises a light source bin for tetrachloro-o-xylene production, a plurality of adjusting bases are fixedly mounted on the inner wall of the top of the light source bin, and illumination mechanisms are arranged on the adjusting bases; a plurality of storage grooves are formed in the inner wall of the bottom of the light source bin, material barrels are placed in the storage grooves, a sealing base is fixedly installed on one side of the light source bin, a sealing door is rotatably installed on the inner side of the sealing base, and an observation window is fixedly installed on one side of the light source bin. According to the utility model, each group of light sources can be accurately adjusted, so that illumination dead angles are avoided, meanwhile, the condition that raw materials are not uniformly illuminated can be avoided, the purity of manufactured tetrachloro-o-xylene is higher, and the practicability of the equipment is improved.

The application discloses a preparation method of 2,2'-di(trifluoromethyl)-4,4',5,5'-biphenyl dianhydride, which comprises the following steps: ① iodization reaction of o-xylene to obtain 1,2-diiodo-4,5-xylene; ② coupling reaction of the product of step ① to obtain 2,2'-diiodo-4,4',5,5'-tetramethyl biphenyl; ③ trifluoromethylation of the product of step ② to obtain 2,2'-di(trifluoromethyl)-4,4',5,5'-tetramethyl biphenyl; ④ oxidation of the product of step ③ with an oxidant to obtain 2,2'-di(trifluoromethyl)-4,4',5,5'-biphenyl tetraacid; and ⑤ dehydration and cyclization of the product of step ④ to obtain 2,2'-di(trifluoromethyl)-4,4',5,5'-biphenyl dianhydride. The synthetic route provided by the application has the advantages of mild reaction condition, simple treatment, high efficiency and low cost.

The invention belongs to the technical field of analysis and detection, and particularly relates to an HPLC (High Performance Liquid Chromatography) quantitative detection method for o-methylbenzyl chloride and impurities thereof. The method comprises the following steps: preparing a blank solution, a test solution and a reference solution, respectively injecting the blank solution, the test solution and the reference solution into a liquid chromatograph, recording chromatograms, and calculating according to a peak area normalization method to obtain the content of o-methylbenzyl chloride in the test solution. The content of o-xylylene dichloride and / or o-xylene in the test solution is calculated according to the peak area by an external standard method, and the content of other impurities in the test solution is calculated according to a main component self-contrast method. The separation degree of the main peak and each impurity peak is good, and the precision, the accuracy, the stability, the durability and the reproducibility are all excellent. And a detection technology is provided for quality control of o-methylbenzyl chloride.

The invention relates to the technical field of organic synthesis and preparation, in particular to a multi-step synthesis process for preparing o-trifluoromethyl benzoyl chloride from o-xylene, which comprises the following steps: oxidation preparation of o-toluic acid: adding o-xylene and a solvent into a reaction container, reacting under the action of an oxidation system, and separating to obtain o-trifluoromethyl benzoyl chloride; after the reaction is finished, carrying out post-treatment to obtain o-toluic acid; by optimizing the process for preparing o-toluic acid through oxidation, selecting an adaptive catalytic system and accurately regulating and controlling reaction conditions, the problems of low oxidation efficiency, more raw material residues and excessive oxidation in the existing process are effectively solved, the yield and purity of o-toluic acid are remarkably improved, a high-quality raw material is provided for subsequent steps, and the method is suitable for industrial production. The efficiency and the product quality of the whole preparation process are guaranteed from the source.

This invention provides a method for the oxidation of o-xylene to phthalide, comprising reacting o-xylene with an oxidant in the presence of a catalyst, wherein the catalyst comprises at least two transition metal ions and carbon nanotubes. The method for the oxidation of o-xylene to phthalide provided by this invention utilizes a composite catalyst of at least two transition metal ions and carbon nanotubes, effectively improving the selectivity of phthalide.

The invention relates to the field of engineering plastics, in particular to a low-precipitation high-toughness glass fiber reinforced PBT (polybutylene terephthalate) composite material and a preparation method thereof. The PBT composite material comprises the following components in percentage by mass: 80.00 to 85.00 percent of polybutylene terephthalate resin; 12.00% to 18.00% of reinforcing fibers; 1.00% to 3.00% of a precipitation-resistant silicon-based modifier; 0.10% to 0.20% of an antioxidant; 0.10% to 0.20% of a lubricant; wherein the precipitation-resistant silicon-based modifier is prepared by pretreating diatomite with a silicon hydroxyl activating treatment agent and then carrying out surface grafting reaction on the pretreated diatomite and an epoxy-based interface compatilizer; the precipitation amount of the composite material after being refluxed in o-xylene for 24 hours is lower than 0.65%, and the notch impact strength is not lower than 4.35 KJ / m < 2 >. The diatomite is subjected to surface grafting modification, so that the precipitation amount of the PBT composite material is lower than 0.65%, the impact strength is still kept to be higher than 4.50 KJ / m < 2 >, and the refrigerant resistance and the toughness are synergistically improved.

The application belongs to the technical field of high polymer materials, and particularly relates to a synthesis process of 2,3,6,7-naphthalene tetracarboxylic dianhydride. The steps are as follows: alpha,alpha,alpha',alpha',4,5-hexabromo-o-xylene is reacted with 2-(triphenylphosphoranyl) butanedioic acid dialkyl ester in an organic solvent in the presence of an acid-binding agent to obtain 6,7-dibromo-2,3-naphthalene dicarboxylate; the 6,7-dibromo-2,3-naphthalene dicarboxylate is reacted with a cyanation reagent to obtain 6,7-dicyano-2,3-naphthalene dicarboxylate; the 6,7-dicyano-2,3-naphthalene dicarboxylate is hydrolyzed in an alkaline aqueous solution, and after the reaction is completed, acidification is performed to obtain 2,3,6,7-naphthalene tetracarboxylic acid; and the 2,3,6,7-naphthalene tetracarboxylic acid is dehydrated in an acid anhydride environment to obtain 2,3,6,7-naphthalene tetracarboxylate dianhydride. The application has the advantages that raw and auxiliary materials are easy to obtain and low in cost, is suitable for mass industrial production, the synthesis process avoids harsh environments such as high temperature and high pressure, the conversion rate is high, the product quality is stable, and high-purity products can be obtained.

The invention pertains to a process for producing a biaryl compound having at least 2 aryl moieties by cross dehydrogenative coupling (CDC) comprising the step of reacting aryl compounds comprising at least one aryl carbon-hydrogen bond in the presence of an oxidant and a catalyst system comprising a Pd salt and an S,O-ligand, the S,O-ligand comprising at least one oxygen atom and at least one sulfur atom. The process according to the invention makes it possible to manufacture biaryl compounds having at least two aryl moieties in an efficient and cost-effective manner from widely available starting materials. The process can be carried out in under conditions which are attractive for commercial operation while showing attractive yield and selectivity. In one embodiment the synthesis of 3,3',4,4'-tetramethyl-1,1'-biphenyl from o-xylene makes it possible to obtain a 4,4' biphthalic anhydride in two steps rather than in four steps as described above.

The application discloses a method for preparing o-phthalaldehyde from o-xylene. V2O5-TiO2 doped with metal elements is used as a catalyst, o-xylene and an oxygen-containing gas are reacted to obtain a mixed oxidation product containing o-phthalic anhydride, o-phthalic acid and phthalide; the mixed oxidation product is reacted with a reducing agent in a solvent, and o-phthalalcohol is obtained after separation; and the o-phthalalcohol is reacted with an oxidizing agent, and o-phthalaldehyde is obtained after separation. The application avoids the use of corrosive substances such as bromine or chlorine and nitric acid, has low requirements on equipment, is small in environmental pollution, and is high in overall yield of o-phthalaldehyde.

The invention belongs to the field of catalysts, and particularly relates to a method for recovering fullerene from a fullerene-containing supported catalyst, which comprises the following steps: carrying out reflux extraction or Soxhlet extraction on the fullerene-containing supported catalyst by using an organic solvent, carrying out solid-liquid separation on the obtained extract, and collecting a liquid-phase substance; wherein the organic solvent comprises one or more of toluene, carbon disulfide, p-xylene, m-xylene and o-xylene, the active component of the supported catalyst comprises one or more of IB group metal and VIII group metal, and the carrier of the supported catalyst comprises at least one oxide; and concentrating and drying the liquid phase substance to obtain the recovered fullerene. The invention also relates to the recovered fullerene. According to the method, the recovery rate of the fullerene is high, and the purity of the recovered fullerene is high.

The invention discloses a continuous reaction system for producing 2-hydroxy-benzonitrile, which comprises two groups of batching kettles, a static mixer, a micro-channel reactor and a heat exchanger, the two groups of batching kettles are respectively salicylamide-o-xylene solution preparation kettles and thionyl chloride-catalyst system preparation kettles; the batching kettle is communicated with the static mixer through a pipeline, the static mixer is communicated with the micro-channel reactor, reaction liquid enters the heat exchanger from an outlet of the micro-channel reactor for cooling, an outlet of the heat exchanger is communicated with an inlet of the degassing tower, the bottom of the degassing tower is communicated with an alkalization kettle, and the alkalization kettle is communicated with a multi-stage crystallization kettle. And the multi-stage crystallization kettle is communicated with a vacuum drying box. According to the system disclosed by the invention, the degassing tower, the alkalization kettle and the multi-stage crystallization are connected in series, so that the integration of reaction, separation and purification is realized. The degassing tower adopts nitrogen stripping to recover unreacted SOCl2, and three-stage tail gas absorption is matched, so that the utilization rate of SOCl2 is increased to 95% or above, and the environmental protection requirement is met.

The application discloses a chlorinated phthalic anhydride production method, and relates to the chemical industry field, and aims at solving the problem of repeatedly increasing and decreasing pressure and temperature during the production of chlorinated phthalic anhydride. The chlorinated phthalic anhydride production method comprises the following steps: under the action of a catalyst, taking chlorinated o-xylene and acetic acid as raw materials, taking air as an oxidant, and performing an oxidation reaction in an oxidation reactor to obtain a gas phase product and an oxidation reaction liquid; the oxidation reaction liquid at least contains chlorinated phthalic acid, and the gas phase product at least contains acetic acid; performing acetic acid separation on the gas phase product to obtain acetic acid and a purified reaction liquid; then performing dehydration on the purified reaction liquid to obtain a crude anhydride product; and at least two chlorinated phthalic anhydride monomers are separated from the crude anhydride product. The chlorinated phthalic anhydride production method is used for producing chlorinated phthalic anhydride monomers.

The invention relates to the field of chemical equipment, in particular to a device and method for preparing phthalic anhydride from mixed raw materials of o-xylene and naphthalene, and the device comprises an air compressor, an o-xylene storage tank, a naphthalene storage unit, an oxidation reactor and a crude product storage tank, the naphthalene storage unit comprises a naphthalene storage tank and a support arranged on the periphery of the naphthalene storage tank, a ton bag can be placed between the naphthalene storage tank and the support, a first lifting rope and a second lifting rope are installed on the ton bag, the first lifting rope is led out from the four top corners of the upper surface of the ton bag, and the second lifting rope is led out from the two top corners of the lower surface of the ton bag. A first crane and a second crane are arranged on the support, an opening is formed in the top of the naphthalene storage tank, a feeding unit is installed on the opening and comprises a feeding hopper, a cutting device is arranged on one side wall in the feeding hopper, and the cutting device can cut the side wall, making contact with the cutting device, of a ton bag. The naphthalene storage unit provided by the invention provides a convenient scheme for unloading flaky naphthalene packaged by ton bags. The preparation method provided by the invention is high in raw material conversion rate and good in selectivity.

Provided are: a solid composition capable of forming a coating film having excellent light resistance and impact resistance; a method for producing the solid composition; a powder coating material; and a method for producing a coated article. The solid composition of the present invention comprises: a fluorine-containing copolymer having a unit based on chlorotrifluoroethylene and a unit based on vinyl ether; a compound containing a piperidinyl group; ethylbenzene; and a mixed xylene containing o-xylene, m-xylene, and p-xylene.

The invention discloses a method for nitration synthesis of nitro-o-xylene by using a micro-channel reactor. The method comprises the following steps: (1) respectively conveying nitric acid and o-xylene into the micro-channel reactor through a constant flow pump; (2) mixing and contacting the two streams of liquid in the micro-channel reactor and reacting, and after the reaction is completed, enabling the mixed reaction liquid to flow out from an outlet of the micro-channel reactor; (3) after the mixed reaction liquid flows out, introducing the mixed reaction liquid into an oleic acid separation process to separate an organic phase from waste acid; and (4) introducing the separated organic phase into a rectification process to respectively obtain 3-nitro-o-xylene and 4-nitro-o-xylene. The micro-channel reactor is used for synthesizing the nitro-o-xylene, the reaction safety and selectivity are improved by accurately controlling the reaction conditions and the material ratio, and meanwhile waste acid and other impurities are effectively removed through the oleic acid separation procedure; and the rectification process ensures the high-purity separation of 3-nitro-o-xylene and 4-nitro-o-xylene.