179 results about "M-Xylene" patented technology

The invention provides a strain of Mycobacterium sp.16F for efficiently degrading polycyclic aromatic hydrocarbon and benzene organic matters, which has a preservation number of CGMCC No.6367. The mycobacterium 16F can efficiently, safely and rapidly degrade polycyclic aromatic hydrocarbons and benzene organic matters, can grow and degrade by using fluorene, naphthalene, anthracene, acenaphthene, phenanthrene, pyrene and benzopyrene as the sole carbon source and energy in aerobic condition, and can utilize benzene, m-xylene, toluene, salicylic acid, catechol and other multiple aromatic organic matters. The mycobacterium 16F is sensitive to streptomycin, rifampin, tetracycline, kanamycins and other antibiotics, has good degradation effects to mixed polycyclic aromatic hydrocarbons in aging soils and monocyclic benzene organic matters in water bodies, can be used for restoring and purifying the water-soil environment combinedly polluted by aromatic hydrocarbon organic matters, is important for promoting sustainable development, and has a wide application prospect.

The invention belongs to the technical field of tobacco packing box, and in particular relates to a method for detecting contents of 21 volatile organic compounds (VOC), including benzene, methyl benzene, p-xylene, m-xylene, o-xylene, styrene, methanol, ethanol, acetone, isopropyl alcohol, methyl acetate, normal propyl alcohol, ethyl acetate, butanone, acetic acid isopropyl ester, n-butyl alcohol, propylene glycol monomethyl ether, n-propyl acetate, propylene glycol monoethyl ether, 4-methyl-2-pentanone, butyl acetate, cyclohexanone in a tobacco packing box. The method for detecting 21 volatile organic compounds in the tobacco packing box disclosed by the invention comprises the following steps of: sample pretreatment: preparing a piece of hard box packing paper; cutting and reserving a main packing surface by an area of 22.0cm*5.5cm; rolling the printing surface of the sample inwards to obtain a barrel-shaped part; putting the barrel-shaped part in a headspace bottle; adding 1000mu l of glycerol triacetate; sealing, and implementing a headspace-gas chromatography detection. The method disclosed by the invention is high in sensitivity, high in recovery rate, and excellent in precision of detecting result.

Methods for making carbon materials are provided. In at least one specific embodiment, the method can include combining one or more polymer precursors with one or more liquids to produce a mixture. The mixture can be an emulsion, dispersion, or a suspension. The liquid can include hexane, pentane, cyclopentane, benzene, toluene, o-xylene, m-xylene, p-xylene, diethyl ether, ethylmethylketone, dichloromethane, tetrahydrofuran, mineral oils, paraffin oils, vegetable derived oils, or any mixture thereof. The method can also include aging the mixture at a temperature and time sufficient for the polymer precursor to react and form polymer gel particles having a volume average particle size (Dv,50) of the polymer particles in gel form greater than or equal to 1 mm. The method can also include heating the polymer gel particles to produce a carbon material.

The invention discloses a method for adsorbing and separating paraxylene and ethylbenzene from C8 aromatic components. The method comprises the following steps: performing liquid-phase adsorption and separation on C8 aromatic hydrocarbons, thereby obtaining extracted oil rich in paraxylene and raffinate oil rich in ethylbenzene, m-xylene and o-xylene; introducing the raffinate oil into a gas phase adsorption and separation column, adsorbing ethylbenzene from the raffinate oil under the conditions of 190-270 DEG C, 0.4-0.8MPa and gas phase, allowing the non-adsorbed components to flow out of the gas phase adsorption and separation column to serve as adsorption residues, and purging an adsorbent bed layer by using purge gas under the pressure not less than the adsorption pressure, wherein the purged intermediate components is used as gas phase adsorption feedstock; reducing the pressure to 0.1-0.3 MPa, introducing the purge gas to desorb the adsorbed ethylbenzene so as to obtain the aspirate, performing xylene isomerization on the adsorption residues, wherein the isomerization products are taken as raw materials of the above liquid phase adsorption and separation. According to the method, the high-purity paraxylene and ethylbenzene can be separated from the C8 aromatic components, the adsorption residues hardly contain ethylbenzene, and isomerization can be performed under the non-hydrogen and low-temperature conditions.

The invention relates to a method for synthesizing BTX aromatic methyl into unsym-trimethyl benzene. The method takes BTX aromatic hydrocarbon (comprising any one or more of benzene, toluene, o-xylene, m-xylene, p-xylene and mixed xylenes) and a methylating agent (selected from one or more of methyl alcohol, dimethyl ether and methane chloride) as raw materials to prepare unsym-trimethyl benzene by a methylation reaction under the catalytic action of an acid catalyst. The acid catalyst is selected from any one of halide, liquid acid, complexacid, heteropolyacid, solid super acid, acidic ion exchange resin, acidic oxide, hydrogenous zeolite molecular sieve or supported acid catalyst. The pressure of the methylation reaction is 0.01-10.0Mpa, the temperature is 30-700 DEG C, the mass space velocity of raw material liquid is 0.1-10.0h<-1>, and the mole ratio of the aromatic hydrocarbon and the methylating agent is 1:10 to 10:1. The methylation reaction can adopt a continuous fixed bed reaction or continuous stirred-tank reaction. The method has rich raw material resources, low cost, mild reaction condition as well as higher once-through conversion of the raw materials and yield of the unsym-trimethyl benzene.

To provide a release film which has an extremely low gas permeability, an enormously small mold contamination by a mold resin and a high releasability.A gas barrier release film for semiconductor resin molds, comprising a release layer (I) having excellent releasability, a plastic support layer (II) supporting the release layer, and a gas restraint layer (III) made of a metal or a metal oxide, formed between the release layer and the support layer, and having a xylene gas permeability of at most 10−15 (kmol m / (s·m2·kPa)) at 170° C. The release layer (I) is preferably formed from a fluororesin such as an ethylene / tetrafluoroethylene copolymer, and a metal oxide layer is preferably a layer of an oxide such as an aluminum oxide, a silicon oxide or a magnesium oxide.

A method for production of p-xylene comprises the steps: a raw material containing a C8 aromatic hydrocarbon mixture goes into a rectifying tower, the C8 aromatic hydrocarbon mixture is separated from the lateral line of the rectifying tower, light hydrocarbons having the carbon number of 7 or less are obtained at the tower top, and heavy hydrocarbons having the carbon number of 9 or more are obtained at the tower bottom; the C8 aromatic hydrocarbon mixture goes to an adsorption separation unit, and is subjected to contact separation with an adsorbent to obtain a p-xylene, or m-xylene or ethylbenzene material flow; the remaining C8 aromatic hydrocarbons go to an isomerization unit, and under the action of an isomerization catalyst, isomerized C8 aromatic hydrocarbons are generated and are used as feeding materials to circularly return to the rectifying tower. With adopting of the method for production of p-xylene, equipment investment and occupied land area can be reduced, energy consumption also can be reduced, business operation costs are reduced, and economic benefits and social benefits are improved.

The invention relates to a method for preparing m-phenylenediamine. The method comprises the following steps of: (1) preparing m-phthalamide by taking m-xylene as an initial raw material; and (2) reacting isophthalamide with hypohalite or halogen in an alkaline solvent to prepare m-phenylenediamine. Compared with the prior art, the method for preparing m-phenylenediamine completely avoids a mixedacid nitration process, does not generate waste acid, does not generate a strong explosive compound dinitrobenzene, and is safe, clean and efficient.

The invention relates to a high-silicon MFI zeolite adsorbent without adhesive and a preparation method thereof, which mainly aim at solving the problems of small adsorption capacity of an adsorbent for PX in mixed xylene C8, as well as low adsorption rate and poor separation effect in the prior art. The high-silicon zeolite adsorbent without adhesive is prepared through the steps of adding high-silicon MFI powder in specific grain size distribution into a silicon adhesive for forming and performing crystal transformation, wherein the grain size of the adsorbent is 16-40 meshes; at room temperature, when a solid-liquid ratio is 3 to 5, the adsorption capacity of per gram of adsorbent for p-xylene in a 1,3,5-trimethylbenzene solution containing 10% of p-xylene based on weight percent is greater than 0.102g, the selectivity coefficient of p-xylene for ethylbenzene, o-xylene and m-xylene is higher than 9.0, and within initial three minutes, the adsorption rate of the per gram of adsorbent for p-xylene is greater than 22mg / minute. By virtue of the technical scheme, the technical problems are well solved and the high-silicon MFI zeolite adsorbent without adhesive can be used for separation of p-xylene in C8 arene.

A decorative film having an outer layer containing a polyamide composition with the following components: a) from 50 to 100 parts by weight of polyamide prepared from: alpha) from 70 to 100 mol % of diamine selected from m-xylylenediamine, p-xylylenediamine and mixtures thereof, beta) from 0 to 30 mol % of other diamines having from 6 to 14 carbon atoms, and gamma) from 70 to 100 mol % of aliphatic dicarboxylic acids having from 10 to 18 carbon atoms and delta) from 0 to 30 mol % of other dicarboxylic acids having from 6 to 9 carbon atoms, and b) from 0 to 50 parts by weight of another polyamide, where a) and b) total 100, having good chemicals resistance, good stress cracking resistance, improved scratch resistance, and improved gloss. Typical application are vehicle manufacture and use as surface lacquer of ski and sled.

The invention discloses a method for measuring the content of benzene and benzene series in hot melt glue. The method comprises the following steps of: selecting benzene, methylbenzene, ethylbenzene, o-xylene, p-xylene or m-xylene as standard substances of the benzene and the benzene series, and gradually diluting to form a standard working solution by taking glyceryl triacetate as a matrix correction fluid; taking a hot melt glue sample and adding the hot melt glue sample into the matrix correction fluid, and detecting and analyzing the standard working solution and the sample by using a headspace gas chromatography mass spectrometry; and finally, drawing a standard curve and calculating a result. In the invention, a complex pretreatment process of the sample, and influences and interference caused by volatile components in the sample are eliminated. According to the method, the recovery rate ranges from 95% to 101%, the average relative standard deviation ranges from 3.04% to 4.14%, and the repeatability is good.

Base compounds including 1,3-oxazinan-6-one derivatives of N-alkyl or N-alkenyl or N-cycloalkyl or N-aryl propionic acids and paraformaldehyde, and their application as corrosion inhibitors with multifunctional properties serving as inhibitory / dispersant of asphaltene in production processes, transportation, refining and storage of crude oil and derivatives. The corrosion inhibitor with inhibitory / dispersant of asphaltenes properties comprises an active substance base of 1,3-oxaninan-6-ones and hydrocarbon solvents such as benzene, toluene, mixed xylenes, o-xylene, m-xylene and p -xylene, diesel, kerosene, jet fuel, alcohols, aliphatic branched and unbranched alcohols containing from 3 to 10 carbon atoms, such as isopropanol, butanol and pentanol, and mixtures of hydrocarbon solvents with aliphatic branched or unbranched liquid fuels. In addition, a process for obtaining 1,3-oxazinan-6-ones derivatives of N-alkyl or N-alkenyl or N-cycloalkyl or N-aryl propionic acids and paraformaldehyde is described.

The present invention discloses a method and an apparatus for preparing p-xylene from methanol. The method is mainly characterized in that first methanol feedstock produces a methanol aromatization reaction in a methanol aromatization reactor (2), and liquefied gas feedstock, a methanol aromatization gas product and non-aromatic raffinate oil separated from an aromatic hydrocarbon extraction apparatus produce a low-carbon hydrocarbon aromatization reaction in a low-carbon hydrocarbon aromatization reactor (6); second methanol feedstock as well as benzene and methylbenzene separated from an aromatic hydrocarbon rectifying tower (12) produce an alkylation reaction in an alkylation reactor (19), o-xylene, m-xylene and ethylbenzene separated from the aromatic hydrocarbon rectifying tower produce an isomerization reaction in an isomerization reactor (20), and fresh raw material benzene as well as C9 and aromatic hydrocarbons separated from the aromatic hydrocarbon rectifying tower produce a transalkylation reaction in a transalkylation reactor (21). P-xylene (13) separated from the aromatic hydrocarbon rectifying tower serves as a product. The present invention discloses the related apparatus. The method and the apparatus can produce p-xylene as much as possible.

The invention discloses a method for preparing m-xylene diamine by continuous hydrogenation, which adopts m-phthalonitrile as the raw material and carries out multi-phase hydrogenation. The method is characterized in that the mixture of m-phthalonitrile and a solvent and hydrogen contact a granular solid catalyst in a slurry bed reactor to carry out continuous hydrogenation reaction; the reactive solution and the solid catalyst are continuously fed into a separator for liquid-solid separation; the separated reactive solution is separated to obtain the final product; and the separated catalyst can be recycled after regeneration and returned to the slurry bed reactor. The method can achieve continuous hydrogenation of m-phthalonitrile, and has the advantages of good conversion rate and selectivity, convenient operation, and high equipment utilization rate and hydrogenation efficiency, and the catalyst is not easy to abrade and crush and can be continuously regenerated and recycled.

The invention discloses a preparation method of tetraglycidyl m-xylene diamine epoxy resin, which comprises the following steps: (1) adding epichlorohydrin and deionized water into a reaction device, dropwisely adding m-xylene diamine for a ring-opening reaction; (2) adding an aqueous alkali into the material obtained in step (1) for a ring-closure reaction, wherein the molar ratio of the alkali in the aqueous alkali to the m-xylene diamine is 4:1; (3) after the reaction, recovering epichlorohydrin, adding an inert solvent and deionized water, performing extraction layering, removing the water layer; (4) refining the organic layer with the aqueous alkali, wherein the molar ratio of the alkali in the aqueous alkali to the m-xylene diamine is 1:1-2.5:1; (5) washing the refined material with water, removing the solvent to obtain the tetraglycidyl m-xylene diamine epoxy resin. The method of the invention is simple in process, easy to implement, and low in cost, and the prepared tetraglycidyl m-xylene diamine epoxy resin has low viscosity, low organic chloride content, and a high epoxy value.

Polyester films which comprise not only thermoplastic polyester, e.g. polyethylene terephthalate, but also from 5 to 45% by weight of poly(m-xyleneadipamide) and optionally from 0.02 to 1% by weight of fillers, and which have, on at least one surface, an adhesion-promoting layer comprised of a hydrolyzed amino-functional silane. The films of the invention are produced by a sequential stretching process, and feature improved mechanical properties, such as a modulus of elasticity greater than 3500 N / mm2 in both orientation directions, high gloss, low haze, and very good barrier properties with respect to oxygen transmission. Films of the invention are therefore a suitable packaging material for foods and other consumable items, and as starting material for production of laminates via extrusion coating.

The present invention is an improved process and apparatus for producing para-xylene, particularly with respect to a process that involves the methylation of toluene and / or benzene to selectively produce para-xylene, wherein streams having differing amounts of ethylbenzene are separately treated in the recovery of para-xylene. A first hydrocarbon feed comprising xylenes and ethylbenzene is provided to a first para-xylene adsorption section, and a second hydrocarbon feed comprising xylenes and less EB than the first hydrocarbon feed is provided to a second para-xylene adsorption section. Segregating the feeds with differing ethylbenzene contents increases the overall efficiency of the adsorption of para-xylene by the adsorption units. Efficiency and energy savings may be further improved by subjecting the lower-content ethylbenzene stream to liquid phase isomerization.

The invention discloses a GC-MS method for measuring volatile characteristic organic matters in water based on multifunctional on-line sample introduction. According to the method, two kinds of onlinepretreatment methods of headspace and dynamic headspace of benzene series (benzene, methylbenzene, ethylbenzene, p-xylene, m-xylene, o-xylene, isopropyl benzene, chlorobenzene and styrene) are established; two kinds of online pretreatment methods of a solid-phase micro-extraction method and a magnetic stirring adsorption extraction method of two kinds of odor substances (geosmin and dimethyl isocamphitol), and four kinds of a formula which is as shown in the specification are established; and then online sample introduction GC-MS detection is carried out. The detection result shows that the detection limit, the recovery rate, the precision and the like of the on-line method for detecting the volatile organic matters in the three categories can meet the measurement requirements; the onlinedetermination efficiency is improved by one half to two thirds, and the method is simple, convenient, environment-friendly and efficient. According to the method, the sample detection sensitivity iseffectively improved by adding the aid and a secondary adsorption mode, and meanwhile, the traditional thermal desorption sample introduction mode is changed, and the accuracy and operability of sample detection are both optimized.

The present invention discloses a method for producing aromatic carboxylic acid by m-xylene and ethylbenzene multi-step co-oxidation. The method includes the following steps of: (1) rectifying p-xylene raffinate containing p-xylene, m-xylene, o-xylene and ethylbenzene to remove o-xylene and obtain mixture A containing o-xylene and ethylbenzene; (2) subjecting the mixture A to multi-step oxidation to produce a mixture B containing isophthalic acid and benzoic acid, and separating the mixture B by crystallization to obtain a crude product of isophthalic acid and crystallizing mother solution to obtain benzoic acid by evaporation and concentration; (3) washing the crude product of isophthalic acid using acetic acid and distilled water respectively and drying to obtain refined isophthalic acid. The steps of the production process and each unit operation are simple and feasible. In the meantime, the method has no organic wastewater discharged, and is a new economic and environmental protection process.

Biaxially oriented polyester films which have a polyester-containing base layer (B) and at least one overlayer (A) which comprises poly(m-xyleneadipamide) (MXD6) feature improved optical properties such as increased gloss and very good barrier properties, in particular toward passage of oxygen, and are therefore suitable as packaging materials for foods and other consumable items.

The invention discloses a preparation method of an m-xylene adsorbent. The method comprises the following steps: (1) uniformly mixing Y zeolite and kaolin to obtain initial molding powder, wherein thekaolin content is 1-10% by mass; putting the initial molding powder into rolling forming equipment; spraying water while rolling until all the powder is gathered into pellets so as to obtain initially-formed pellets; and (2) spraying water on the initially-formed pellets prepared in the step (1) while adding later-stage molding powder for later-stage ball rolling molding, wherein the later-stagemolding powder consists of 11-100 mass percent of kaolin and 0-89 mass percent of Y zeolite; drying the molded pellets, roasting at the temperature of 500-700 DEG C, treating with an alkaline solutionfor in-situ crystallization, and drying. The adsorbent prepared by the method has high compressive strength and burning bulk density, good adsorption selectivity and good mass transfer performance.

The invention relates to metal cutting gas. The metal cutting gas is prepared from natural gas and additives, and the additives are prepared from p-xylene, ethylbenzene, m-xylene and ferrocene. The cutting temperature of the natural gas metal cutting gas is higher than or equal to that of traditional acetylene gas, cutting quality is good, the source is wide, the preparation cost is low, and using is quite safe.

The invention discloses a method for preparing 2,2-dimethyl-3-hydrocinnnamic aldehyde and a derivative thereof. In the method, the conventional and easily obtained alkyl-substituted benzene (including m-xylene, p-xylene, o-xylene and sym-trimethyl benzene) is taken as the raw material, and the derivative using the 2,2-dimethyl-3-hydrocinnnamic aldehyde as a matrix is obtained through Blanc bromomethylation and isobutylaldehyde alkylation. The method adopts the economical and easily obtained raw materials in the chemical industry market to synthesize the derivatives of the 2,2-dimethyl-3-hydrocinnnamic aldehyde by different methods, and the derivatives are substituted by two methyl in different positions on a benzene ring. The flavors of the derivatives are described. The benzyl bromide and isobutyraldehyde are used for alkylation reaction, thus shortening the reaction time and increasing the yield.

Polyester films which comprise not only thermoplastic polyester, e.g. polyethylene terephthalate, but also from 5 to 45% by weight of poly(m-xyleneadipamide) and optionally from 0.02 to 1% by weight of fillers. The inventive films have at least one adhesion-promoting surface and are produced by a sequential stretching process. The inventive films feature improved mechanical properties, such as a modulus of elasticity greater than 3500 N / mm2 in both orientation directions, high gloss, low haze, and very good barrier properties with respect to oxygen transmission. The inventive films are therefore suitable as packaging material for foods and other consumable items.

The invention provides a preparation method of 3,5-dimethylphenol. The method comprises the following steps: xylene (one or a mixture of o-xylene, m-xylene and p-xylene) and alkyl halide or anhydride are subjected to a reaction under the effect of a catalyst, and an intermediate 3,5-dimethylcarbonyl compound is produced under a certain condition; the intermediate is oxidized under the effect of a peroxide, such that 3,5-dimethylphenol ester is produced; and 3,5-dimethylphenol ester is hydrolyzed, such that 3,5-dimethylphenol is obtained. According to the method, xylene is adopted as an initial raw material, and is processed through the tree steps of carbonylation, oxidation and hydrolysis, such that a target product can be prepared with high yield. Therefore, an assumption of synthesizing 3,5-dimethylphenol with high yield under a mild condition is made possible. Compared to prior arts, the method provided by the invention has the advantages of low raw material cost, less three-waste, and mild reaction condition. The method is especially suitable for large-scale productions.

Polyester films which comprise not only thermoplastic polyester, e.g. polyethylene terephthalate, but also from 5 to 45% by weight of poly(m-xyleneadipamide) and optionally from 0.02 to 1% by weight of fillers. The polyester films have been ceramic-coated or metallized on at least one surface, and are produced by a sequential stretching process. The films of the invention feature improved mechanical properties, such as a modulus of elasticity greater than 3500 N / mm2 in both orientation directions, high gloss, low haze, and very good barrier properties with respect to oxygen transmission. The inventive films are therefore a suitable packaging material for foods and other consumable items.

The invention relates to a separation method of a toluene, methanol, isopropanol and dimethyl carbonate mixture. An apparatus used for realizing the method comprises a first extraction rectifying tower, a second extraction rectifying tower, an alcohol separating tower and a toluene tower, and o-xylene, m-xylene and p-xylene are adopted to extract and rectify toluene, methanol, isopropanol and dimethyl carbonate. The purity of each of products comprising toluene, methanol, isopropanol and dimethyl carbonate is high, and the separation cost is low.

The present invention discloses a novel process for the preparation of 1-[2-(2,4-dimethylphenylsulphanyl)phenyl] piperazine. The process uses o-halogenated benzenesulfonic acid and m-xylene as raw materials, which are subjected to dehydration condensation with methylsulfonic acid and phosphorus pentoxide as condensing agents to generate halogenated diarylsulfone. Halogenated diarylsulfone and piperazine are subjected to a substitution reaction in an aprotic solvent to produce piperazine ring substituted diarylsulfone; the piperazine ring substituted diarylsulfone is reduced by hexachlorodisilane in an aprotic solvent to obtain a product with high yield. This method has the advantages of cheap and easily available raw materials, avoidance of the usage of a noble metal catalyst and treatment of residual palladium, simple operation, mild reaction conditions, simple post-treatment, and potential application values.