31 results about "P-Xylene" patented technology

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.

This application provides an isolation structure and its manufacturing method. The isolation structure includes a substrate, an isolation trench, a flexible dielectric layer, and a filling layer located within the substrate. The flexible dielectric layer is made of hydroxyl-para-xylene. The filling layer covers the surface of the flexible dielectric layer and fills the isolation trench. This flexible dielectric layer can reduce cracks caused by excessive stress in subsequent thermal processes and can adapt to spatial distortion caused by the expansion of residual gas in the isolation trench through deformation under thermal conditions, reducing damage to the substrate, enhancing the electron coupling ability of the HiK material, improving the yield of devices on the substrate, and reducing dark current in devices and white spots in display images from the source. In addition, this flexible dielectric layer does not contain metal, so it will not cause metal ion contamination to the substrate. It eliminates the need for an additional isolation layer, improving the performance of devices on the substrate while simplifying device structure and processes and reducing manufacturing costs.

This utility model discloses an integrated drying and gas purification machine for slide staining, including a machine body, a protective door hinged to the left side of the front end of the machine body, a placement platform in the middle of the bottom wall of the machine body, an electric heating wire on the upper side of the inner part of the machine body, a cavity in the lower side of the inner part of the machine body, an air inlet with an air inlet pipe in the left side of the upper end of the machine body, and an exhaust port on the right end of the machine body. It also includes a purification mechanism; the purification mechanism includes a filter chamber, a filter element, a sealing door, and a fixing component. The filter chamber is located on the right side of the inner part of the machine body, and the filter element is placed inside the filter chamber. A sealing door is hinged to the upper side of the top wall of the filter chamber. The fixing component is located inside the filter chamber and is used to fix the filter element. This integrated drying and gas purification machine for slide staining optimizes the driving method, improves the stability of the filter element during purification, and ensures the purification effect of xylene.

The application discloses a kind of xylene gas sensor based on C / MnWO4 core-shell structure nanocomposite and preparation method thereof, belong to gas sensor technical field.Sensor is composed of Al2O3 substrate, Pd metal interdigital electrode, three parts of C / MnWO4 core-shell structure nanocomposite sensitive layer coated on Al2O3 substrate and Pd metal interdigital electrode using hydrothermal method preparation.C / MnWO4 core-shell structure nanocomposite is prepared by growing, crystallizing and enriching MnWO4 nanoparticles on porous loose carbon microspheres and forming active semiconductor shell.The sensor prepared by the application has the characteristics of simple preparation method, low cost and low equipment requirement.The sensor has good selectivity, high response and fast response speed for xylene gas, and has good detection performance for low concentration xylene, is suitable for mass production, and has important application value.

The present application relates to a kind of toluene, methylating agent is obtained in the production method of paraxylene concentration greater than 80% of dimethylbenzene with water vapor as medium to promote reaction.The main problem is that in the existing toluene shape selective methylation fixed bed reaction process, hydrogen and / or nitrogen are used as carrier gas to promote the reaction, which causes high fixed equipment investment, high device material requirements and other problems.The present application solves the problem by shape selective methylation of toluene and methylating agent, adding water vapor instead of hydrogen and / or nitrogen as carrier gas as medium to promote the reaction, and the catalyst para-selectivity is 80-95%, the laboratory life can reach 1000 hours, which can better solve the problem.The method has the advantages of high product purity, no complex separation, simple operation, low fixed asset investment, low material consumption, etc., and can be used for the industrial production of paraxylene.

The present invention provides an oxidation-resistant coating and a surface-modified metal material. The oxidation-resistant coating comprises a chloro-substituted parylene, a fluoro-substituted parylene, and an alkyl-substituted parylene, and the weight ratio of chloro:fluoro:alkyl in the oxidation-resistant coating is 1-10:6-27:2-15. The oxidation-resistant coating can be used to coat the surface of an oxidation-prone metal material to form a surface-modified metal material.

This invention relates to the field of photovoltaic cell technology, specifically to an interface-modified NiOx thin film and its preparation method, comprising: preparing a NiOx thin film; and depositing a solution containing a passivating agent onto the NiOx thin film, wherein the passivating agent is selected from any one of tetraethyl p-xylene diphosphate, diethyl 4,4'-biphenyldimethyl diphosphonate, and 1,4-phenylene di(methylene)diphosphonic acid. This invention effectively passivates NiOx surface defects through bidentate chelation coordination of passivating agent molecules, while simultaneously utilizing a rigid framework to form a dense physical barrier, synergistically improving interface stability and charge transport efficiency, and significantly enhancing the open-circuit voltage, fill factor, and photoelectric conversion efficiency of perovskite solar cells.

An oxidation resistant coating includes a chloro-substituted parylene, a fluorine-substituted parylene, and an alkyl-substituted parylene. A weight ratio of chlorine to fluorine to an alkyl group in the oxidation resistant coating is 1-10:6-27:2-15. The oxidation resistant coating is utilized to coat the surfaces of a metallic body made of a readily oxidizable material for forming a surface-modified metal material.

The disclosed apparatus and method for generation and conversion comprises / uses a fractionation train (4-6) for producing a xylene fraction (24); a xylene separation unit (10) for processing the xylene fraction to produce a para-xylene extract (39) and a raffinate (40); an isomerization unit (11) for processing the raffinate to produce an isomer of xylene (42) sent to the fractionation train; a synthesis gas generation unit (14; 15) for processing a hydrocarbon feedstock (30) to produce a synthesis gas (34) containing CO and CO2; a methanol synthesis reaction section (50) for processing the synthesis gas (34) to produce methanol (51); and a toluene alkylation reaction section (13) for processing a fraction containing toluene (23) with methanol (51) to produce an alkylated effluent (32) containing xylene sent to the fractionation train.

This invention is directed to a corrosion-resistant permanent magnet, to a method for producing a corrosion-resistant permanent magnet, and to an intravascular blood pump comprising the magnet. The magnet is corrosion resistant due to a composite coating comprising a first layer structure and optionally a second layer structure on the first layer structure, each layer structure comprising an inorganic layer, a linker layer on the inorganic layer, and an organic layer formed from poly(2-chloro-p-xylylene) on the linker layer. The inorganic layers comprise aluminum and / or aluminum oxide.

The application discloses a kind of cascade catalyst and its preparation method and preparation method of p-xylene, it is related to catalyst technical field.The cascade catalyst includes first layer catalyst and second layer catalyst that are arranged in cascade and mass ratio is 1: (0.1~10), first layer catalyst is copper doped ZnO-ZrO2, the mass percentage of Cu in first layer catalyst is 0.1-20 wt%;Second layer catalyst includes metal modified molecular sieve, and the modified metal element in metal modified molecular sieve includes at least one of Si, Zn and Ga, and the content of modified metal element is 1wt%~20wt%.The cascade catalyst provided by the application can be used as the catalyst for preparing p-xylene from CO2-rich synthesis gas and toluene after activation, can significantly improve CO, CO2 and toluene conversion rate, effectively inhibit the isomerization reaction of dimethylbenzene, improve the selectivity of target product p-xylene.

This invention relates to the field of molecular sieve adsorbent technology, and particularly to an EMT / FAU composite molecular sieve, its preparation method, and its application. The EMT / FAU composite molecular sieve has a multi-level pore structure of micropores, mesopores, and macropores; and the EMT / FAU composite molecular sieve includes an EMT topological molecular sieve and a FAU topological molecular sieve; the FAU topological molecular sieve is formed by in-situ crystallization of a binder and chemically bonded to the EMT topological molecular sieve. The advantages of this invention are: shortening the intracrystalline diffusion path through small-grained EMT; constructing a multi-level pore network and enhancing compressive strength through in-situ crystallization; and precisely controlling the pore size and adsorption sites through stepwise ion exchange, achieving a high degree of matching with the toluene process using light desorbents; the resulting Sr / Ba-EMT / FAU composite molecular sieve, when used in the separation of p-xylene using light desorbents, exhibits advantages such as fast mass transfer, high selectivity, and good compressive strength.

The invention relates to a method for recovering 2, 5-hexanedione from p-xylene bio-based reaction liquid, which comprises the following steps: uniformly mixing a skeleton monomer, a cross-linking agent, a functional monomer, a pore-foaming agent, an initiator and a dispersing agent, and then carrying out suspension polymerization reaction; collecting the polymeric microspheres, removing the pore-foaming agent, and drying to obtain the polar macroporous adsorption resin for specific separation. A chromatographic column is filled with adsorption resin for column packing, and an adsorption resin separation system is formed; the method comprises the following steps: introducing a p-xylene bio-based reaction liquid containing 2, 5-hexanedione into an adsorption resin separation system, and further adsorbing and separating 2, 5-hexanedione in the p-xylene bio-based reaction liquid; and regenerating the resin by using an eluent, and collecting the 2, 5-hexanedione. Compared with the prior art, the method provided by the invention successfully realizes efficient recovery of p-2, 5-hexanedione from the p-xylene bio-based reaction liquid.

A porous hollow spherical photonic crystal sensor for detecting xylene gas and a method thereof, comprising synthesizing PS@SiO2 core-shell colloids, assembling into spherical photonic crystals by microfluidics, calcining to remove the polystyrene inner core to form a hollow SiO2 structure, and introducing a porous structure by controllable chemical etching. Subsequently, functionalization is performed by using P(VBC-co-MMA) to obtain a porous hollow spherical photonic crystal sensor, which is endowed with strong molecular affinity for xylene, and selective gas adsorption of the porous photonic crystal is realized. Benefiting from the super-symmetrical spherical structure, the obtained photonic crystal sensor exhibits an inherent angle-independent optical response, overcoming the limitation of angle dependence of thin film photonic crystal sensors. Exposure to xylene gas shows a significant reversible red shift of the optical stop band and a clear color change, which is due to the increase of the effective refractive index caused by vapor diffusion and adsorption. By monitoring the movement of the optical stop band in air and saturated xylene, visual detection of xylene gas can be realized.

This invention relates to a method for separating and purifying p-xylene. The method involves contacting a reaction solution containing p-xylene and ketone / aldehyde impurities with a polar macroporous adsorption resin to adsorb and remove at least some of the ketone / aldehyde impurities, obtaining a p-xylene-rich solution. The p-xylene-rich solution is then subjected to distillation to obtain purified p-xylene. Compared with existing technologies, this invention uses macroporous adsorption resin combined with distillation technology to separate and purify p-xylene from bio-based reaction solutions. The product has high purity, stable operation, and is suitable for large-scale production, effectively promoting the industrial application of bio-based p-xylene processes.

This invention provides a catalyst for the liquid-phase oxidation of terephthalic acid and its application. The catalyst comprises a cobalt salt, a zirconium salt, a bromine-containing compound, and an auxiliary agent; the mass ratio of Co, Zr, Br, and the auxiliary agent in the catalyst is 500:(250–350):(500–1200):(30–80); the auxiliary agent is selected from compounds with the structure shown in formula (1), wherein R is selected from C1–C4 alkyl groups. The catalyst for the liquid-phase oxidation of terephthalic acid provided by this invention has a low Br content and good catalytic performance; its application in the liquid-phase oxidation of p-xylene to terephthalic acid can reduce the impurity content in the product and effectively improve the product yield.

A toluene disproportionation method using a treated UZM-44 zeolite is described. This method produces an effluent stream containing para-xylene and benzene. The molar ratio of benzene to xylene in the effluent stream (Bz / X) may be in the range of 1.00 to 1.14, the molar ratio of para-xylene to xylene in the effluent stream (pX / X) may be in the range of 0.80 to 1.0, and the conversion rate of toluene may be 20% to 40%.

Processes and a catalyst for the cycloaddition of an olefin, such as C2 to C4 olefins like, ethylene, propylene and butylene, to a biomass derived compound, such as dimethylfuran, furan, methylfuran. The catalyst has a relatively low silica to alumina ratio of around 25 compared with conventional catalysts which have a ratio greater than 1000. The catalyst has phosphorus and may be a beta zeolite. Such a catalyst can be used to generate a high yield of bio-based para-xylene.

The present application relates to the technical field of liquid phase adsorption separation, and discloses a method for separating and purifying target components from raw materials and application thereof, and a method for separating and purifying p-xylene and / or o-xylene from a C8 aromatic hydrocarbon mixture, which comprises: injecting raw materials F, a weak desorbent D1 and a strong desorbent D2 into a liquid phase simulated moving bed respectively, performing adsorption separation, and taking out extract E containing target components and raffinate R; the liquid phase simulated moving bed comprises n adsorbent layers, and the weak desorbent D1 is injected into the liquid phase simulated moving bed from any layer between the injection point of the strong desorbent D2 and the raffinate R taking-out point along the circulating material flow direction in the simulated moving bed; wherein, the relative selectivity coefficient of the strong desorbent D2 is greater than 1 and the relative selectivity coefficient of the weak desorbent D1 is less than 1 with respect to the target components. The method can improve the separation efficiency of separating and purifying target components from raw materials.

The present disclosure relates to an apparatus for the methylation of aromatic hydrocarbons in an aromatic complex for producing xylene isomer products. More particularly, the present disclosure relates to an apparatus for the selective methylation of toluene and / or benzene in an aromatic complex to produce para-xylene by using treated toluene instead of crude toluene.

This invention relates to the field of catalyst technology, and discloses a catalyst for the aromatization of methanol to p-xylene, its preparation method, and its application. The catalyst includes a support and a metal modifier and / or a non-metal modifier supported on the support; the support includes a porous matrix and a shape-selective confinement modification layer disposed on the outer surface and pores of the porous matrix; the porous matrix includes a ten-membered ring channel acidic molecular sieve; the shape-selective confinement modification layer is an amorphous borosilicate glass. When used in the methanol aromatization reaction, the catalyst of this invention can control the reaction pathway and product diffusion behavior, achieving high p-xylene selectivity and resulting in a high p-xylene content in the product. Furthermore, it can reduce the product purification burden when used for the further preparation of terephthalic acid.

This invention provides an energy-saving secondary crystallization process and system for separating para-xylene. The process includes the following steps: S1, feeding a mixed xylene raw material into a primary dynamic layer crystallizer for dynamic crystallization at -20°C to 0°C, centrifuging the crystallized material to obtain primary crystallization mother liquor and primary crystal crystals, and melting the primary crystal crystals to obtain para-xylene product; S2, feeding the primary crystallization mother liquor into a secondary static crystallizer for static crystallization at -60°C to -20°C to obtain secondary crystal crystals and secondary crystallization mother liquor; S3, melting the secondary crystal crystals and mixing them with the mixed xylene raw material from step S1; S4, passing the secondary crystallization mother liquor through a heat exchanger and a heater sequentially, and then collecting it as a by-product or discharging it externally. This process can simultaneously ensure high product purity, high total yield, and low system energy consumption while maintaining stable operation of the cryogenic system.

Disclosed are a fast fluidized bed reactor, device and method for preparing para-xylene and co-producing light olefins from methanol and / or dimethyl ether and benzene, resolving or improving the competition problem between an MTO reaction and an alkylation reaction during the process of producing para-xylene and co-producing light olefins from methanol and / or dimethyl ether and benzene, and achieving a synergistic effect between the MTO reaction and the alkylation reaction. By controlling the mass transfer and reaction, competition between the MTO reaction and the alkylation reaction is coordinated and optimized to facilitate a synergistic effect of the two reactions, so that the conversion rate of benzene, the yield of para-xylene, and the selectivity of light olefins are increased. The fast fluidized bed reactor comprises a first reactor feed distributor and a plurality of second reactor feed distributors; the first reactor feed distributor and the plurality of second reactor feed distributions are sequentially arranged along the gas flow direction in a reaction zone of the fast fluidized bed reactor.

The application discloses a kind of composite PP-R pipe materials and preparation method and application thereof, it is related to PP-R pipe material technical field, the composite PP-R pipe material, including by inside to outside sequentially connected PP-R inner layer, impact resistance oxygen barrier layer and PP-R outer layer, the impact resistance oxygen barrier layer includes parylene, polyglycolic acid, compatibilizer.The composite PP-R pipe material adds impact resistance oxygen barrier layer as middle layer in it, the material of the impact resistance oxygen barrier layer uses the cooperation of parylene and polyglycolic acid (PGA), with excellent mechanical properties and gas barrier property, and can keep structural performance stable under low temperature environment below-10 DEG C, can be applied in PP-R pipe material system to improve its low temperature brittleness, improve low temperature impact resistance.

The present application relates to the field of paraxylene production, and discloses a method for producing paraxylene and co-producing dimethylnaphthalene. The method comprises: separating C5 + raw materials to obtain C6, C7 and C8 + components; selectively performing hydrodealkylation reaction on the C8 + component to obtain C8 + product; performing aromatic hydrocarbon separation on the C8 + product to obtain C8 component, C9-C 10 component and C 10 + component; performing disproportionation and transalkylation reaction on at least part of the C9-C 10 component and the C7 component to obtain a product rich in dimethylbenzene; performing demethylation reaction on the C 10 + component to obtain C 10 -C 11 component and C 12 + component; performing transalkylation reaction on the C 10 -C 11 component and the remaining part of the C9-C 10 component to obtain a product rich in 2,6-dimethylnaphthalene. The method can realize high-value utilization of by-product naphthalene series and co-production of 2,6-dimethylnaphthalene.