22 results about "Durene" patented technology

The present application belongs to the technical field of aromatic hydrocarbon production, and relates to a method and system for producing trimethylbenzene and quarterphenyl by alkylation. Light aromatic hydrocarbons and methanol are used as raw materials, and alkylation is carried out under the catalysis of a modified molecular sieve catalyst and at a temperature of 250-600 DEG C. The material after alkylation is subjected to further alkylation under the catalysis of the modified molecular sieve catalyst and at a temperature of 250-600 DEG C. The modified molecular sieve catalyst is composed of a molecular sieve and a metal oxide supported in the molecular sieve, the molecular sieve is one or more of HY, Hbeta, IM-5, NU87, EU-1 and mordenite, and the metal in the metal oxide is one or more of Mg, Cu, La, Zn and Mo. The present application solves the technical problems of low content of trimethylbenzene and quarterphenyl components and difficult separation of trimethylbenzene and quarterphenyl in the industrial separation method by directly producing trimethylbenzene and quarterphenyl.

The present application relates to a method for liquid phase oxidation of durene, which comprises: a first stage, in the presence of a catalyst, with acetic acid as a solvent, a liquid phase oxidation reaction of an oxidant source and durene to produce an intermediate mixture, the catalyst containing Co salt, Mn salt, Zr salt and bromide compound; a second stage, adding a mixture of bromide and pure water to the intermediate mixture, and continuing the oxidation reaction with the oxidant source to produce pyromellitic acid; wherein the concentration of oxidant in the oxidant source of the first stage is lower than the concentration of oxidant in the oxidant source of the second stage. By controlling the concentration of oxidant in the oxidant source of the first stage to be lower than the concentration of oxidant in the oxidant source of the second stage in the liquid phase oxidation process of durene, the yield of pyromellitic acid and the purity of crude pyromellitic acid are significantly improved.

The invention belongs to the technical field of organic chemical synthesis, and provides a process for producing pyromellitic dianhydride by liquid-phase oxidation, which comprises the following steps: proportionally adding durene and acetic acid into a batching kettle, matching by using a catalyst, stirring and heating a liquid material to obtain the liquid material, and adding the liquid material into the batching kettle to obtain the pyromellitic dianhydride; when a liquid material is pumped into the micro-channel continuous reactor, the flow of the liquid material pumped into the micro-channel continuous reactor needs to be obtained, pumping peak-valley analysis is carried out according to the flow of the liquid material, a pumping peak time period and a pumping valley time period are screened out, and the change types of the pumping peak time period and the pumping valley time period are identified; according to the method, the oxygen introduction strategy is formulated, the gas introduction adjustment amount is obtained, and the oxygen introduction amount is dynamically adjusted, so that oxygen introduction and liquid material pumping are highly coordinated in the time dimension, and the problems of violent reaction fluctuation or incomplete reaction and the like caused by imbalance of the gas-liquid proportion are solved.

The utility model discloses a reactor pressure stabilizing device for synthesizing durene, which relates to the field of pressure stabilization of an inner cavity of an L fixed fluidized bed and comprises a fixed fluidized bed, a first pressure sensor is mounted on the periphery of the fixed fluidized bed, and the sensing end of the first pressure sensor is inserted into the inner cavity of the fixed fluidized bed. A pressure relief mechanism is installed on the periphery of the fixed fluidized bed and located below the first pressure sensor, a pressure supplementing mechanism is installed at the position, symmetrical to the pressure relief mechanism, of the periphery of the fixed fluidized bed, and a downward pressing mechanism penetrating through an inner cavity of the pressure supplementing mechanism is installed on the periphery of the pressure supplementing mechanism. By arranging the pressure supplementing mechanism and the pressure relief mechanism, the pressure supplementing operation or the pressure relief operation can be performed on the fixed fluidized bed according to the real-time pressure in the fixed fluidized bed, so that the reaction pressure in the fixed fluidized bed is maintained.

The utility model discloses an improved nitrogen supercharging device for synthesizing durene through alkylation of unsym-trimethylbenzene and methanol, which relates to the field of piston type booster pumps and comprises a transverse pipe, a vertical pipe protruding upwards is integrally formed above the outer wall of the transverse pipe, and the inner wall of a top opening of the vertical pipe is in threaded connection with a threaded connector. The threaded connector penetrates to the position above the vertical pipe, a sealing ring is installed at the butt joint position of the vertical pipe and the threaded connector, a hydraulic push cylinder is installed at the top of the threaded connector through a flange piece, a piston plate is installed at the bottom end of a piston rod part of the hydraulic push cylinder, and the hydraulic push cylinder is located in an inner cavity of the vertical pipe. One-way mechanisms are installed at the two ends of the inner wall of the transverse pipe. By arranging the one-way mechanism with the arc-shaped plate, the problem of abrasion caused by reciprocating motion of the ball sealer can be effectively solved, and the problem that the pressurizing effect is reduced further can be solved through the design of the one-way mechanism.

The present application relates to the technical fields of organic chemical synthesis, and discloses a method for synthesizing pyromellitic acid. The method comprises the following steps: (1) under gas-liquid reaction conditions, contacting liquid-phase materials containing durene, a solvent and a catalyst with an oxygen-containing gas in a micro-channel reactor to perform first oxidation, so as to obtain first oxidation materials, wherein the conditions of the first oxidation are such that the conversion rate of the durene reaches more than 99%, and the total molar amount of a monocarboxyl product, a dicarboxyl product and an intermediate product of the oxidation of the monocarboxyl product to the dicarboxyl product in the first oxidation materials is more than 85% of the molar amount of the first oxidation materials; and (2) sending the first oxidation materials into a reaction kettle to perform second oxidation. The method for synthesizing pyromellitic acid provided by the present application has the advantages of high yield, good selectivity, low possibility of blockage of the micro-channel reactor, high oxidation efficiency, safe reaction, economy and environmental protection.

The invention discloses a method for preparing durene by utilizing unsym-trimethylbenzene and methanol, which comprises the following steps: mixing unsym-trimethylbenzene, methanol and hydrogen, heating and gasifying, feeding into a fixed bed reactor, and carrying out alkylation reaction through a molecular sieve catalyst with hierarchical pore distribution to prepare durene, after a reaction product flowing out of the alkylation reactor is subjected to gas-liquid separation and oil-water separation, liquid-phase hydrocarbon components enter a rectification separation system, and light hydrocarbon with the carbon number of C6 or below, methylbenzene, xylene, trimethylbenzene, tetramethylbenzene and aromatic hydrocarbon fractions with the carbon number of C11 or above are separated out. The mesoporous channel of the catalyst increases the contact probability of the raw material and the active site of the molecular sieve, promotes the playing of the activity of the catalyst in a fixed bed, reduces the diffusion resistance of the raw material and the product, promotes the rapid diffusion of the product, and reduces the occurrence of side reactions, so that the conversion rate of unsym-trimethylbenzene and the selectivity of durene are improved; therefore, high durene yield can be obtained.

The present application belongs to the technical field of oil exploration, and relates to a method for identifying late-stage natural gas charging proportion. The method comprises the following steps: calculating a crude oil conversion rate; calculating a calculated value of a gas-oil ratio of a reservoir; establishing a corresponding relationship between the sum of the absolute concentrations of 3-methyl durene and 4-methyl durene and a measured value of the gas-oil ratio of the reservoir; taking the sum of the angle concentrations as a benchmark, adjusting the calculated value of the gas-oil ratio of the reservoir, so that the late-stage natural gas proportion is 0-99%, and obtaining a late-stage natural gas charging proportion identification chart; detecting the sum of the absolute concentrations of 3-methyl durene and 4-methyl durene in the crude oil to be evaluated; and based on the sum of the absolute concentrations and the measured value of the gas-oil ratio of the reservoir, according to the late-stage natural gas charging proportion identification chart, the identification of the late-stage natural gas charging proportion in the oil and gas reservoir to be evaluated is realized. The method is fast, intuitive and easy to operate, and improves the speed and accuracy of the identification of the late-stage natural gas charging proportion.

The application discloses a method for preparing trimethylbenzene and tetramethylbenzene by methylating ethylbenzene-containing octa-aromatic hydrocarbon and methanol. The method comprises the following steps: contacting the ethylbenzene-containing octa-aromatic hydrocarbon and methanol with a methylation catalyst under the condition of hydrogen and / or water to prepare trimethylbenzene and tetramethylbenzene; and the methylation catalyst is a metal-modified surface-silicon-rich ZSM-5 full-crystalline molecular sieve catalyst. The method can strengthen the catalyst's activity of removing ethylbenzene, promote the conversion of ethylbenzene, inhibit the reaction of ethylbenzene and methanol to generate methyl-ethylbenzene byproducts, improve the quality of trimethylbenzene and tetramethylbenzene, improve the quality of C8 aromatic hydrocarbon by effective conversion of ethylbenzene, and reduce the purity and cost requirements of raw materials.

The application relates to a method and system for purifying durene, and belongs to the technical field of durene purification. The method comprises the following steps: performing primary suspension crystallization on durene-rich liquid at a set cooling speed to obtain primary suspension crystallization slurry with a first temperature; performing solid-liquid separation on the primary suspension crystallization slurry to obtain primary suspension crystallization mother liquor and primary suspension crystallization crystals; performing secondary suspension crystallization on the primary suspension crystallization mother liquor at a set cooling speed to obtain secondary suspension crystallization slurry with a second temperature; performing solid-liquid separation on the secondary suspension crystallization slurry to obtain secondary suspension crystallization crystals; and performing layer-type melt crystallization on the mixed crystals of the primary suspension crystallization crystals and the secondary suspension crystallization crystals to obtain durene crystallization products. Under the synergistic action of the two-stage suspension crystallization and the layer-type melt crystallization, the application can realize high yield and high purity of durene, and the method does not have a gasification and condensation process, and has low energy consumption.

The invention discloses a durene feeding device and a durene feeding method, and belongs to the technical field of chemical engineering. The feeding method comprises the following steps: (1) hot air enters from the bottom end of the absorption tower, molten durene is pumped from the top end of the absorption tower, and upward hot air in the absorption tower is saturated by downward molten durene; (2) molten durene flowing out of the bottom end of the absorption tower enters a durene storage tank and is circularly pumped into the absorption tower through a feeding pump; (3) before the saturated hot air flowing out of the top end of the absorption tower enters a buffer tank, the saturated hot air enters gas chromatography through a branch to analyze the content of durene in saturated steam; and (4) saturated steam flowing out of the top end of the absorption tower enters a buffer tank and is mixed with another stream of hot air, and formed mixed gas serves as reaction gas of the single-tube reactor. According to the invention, the feeding amount of durene is stable and adjustable in a range of 22-226 g / h, the concentration of durene in the reaction gas can be controlled at 6.7-26.7 g / m < 3 >, and the requirement of evaluating a pyromellitic dianhydride catalyst on a single-tube reactor is met.

The application discloses a production method of pyromellitic acid. The method comprises the following steps: contacting tetramethylbenzene with a catalyst to generate an oxidation reaction in the presence of an oxygen-containing gas to obtain pyromellitic acid; and the catalyst comprises carbon nanomaterial and alkali metal peroxysulfuric acid hydrogen salt. The pyromellitic acid prepared by the method of the application has no transition metal salt residue, the reaction has no corrosion, and the method of the application has the advantages of high pyromellitic acid yield.

The invention provides a catalyst containing a TPZ-3 / MOR eutectic molecular sieve as well as a preparation method and application of the catalyst. The catalyst comprises a binder, a metal active component, a metal additive and a TPZ-3 / MOR eutectic molecular sieve. The preparation method of the catalyst comprises the following steps: mixing and molding the TPZ-3 / MOR eutectic molecular sieve and the binder, then dipping the molded TPZ-3 / MOR eutectic molecular sieve and the binder in a precursor solution of the metal active component, dipping the molded TPZ-3 / MOR eutectic molecular sieve and the binder in a precursor solution of the metal additive, and then performing activation and reduction to obtain the catalyst containing the TPZ-3 / MOR eutectic molecular sieve. The catalyst disclosed by the invention is applied to isomerization synthesis of durene from tetramethylbenzene, so that the reaction efficiency can be greatly improved, the conversion rate of durene and tetramethylbenzene and the selectivity of durene are remarkably improved, and the yield of durene is improved.

This invention relates to the field of mesitylene production technology, specifically a method for producing benzene and mesitylene from xylene. The method comprises the following steps: xylene undergoes an alkyl transfer reaction catalyzed by a catalyst in a reactor; the reaction products are separated to obtain a xylene-mesitylene mixture and toluene; the xylene-mesitylene mixture is then cryogenically crystallized to obtain mesitylene. This method for producing benzene and mesitylene from xylene produces products with stable composition and high selectivity for mesitylene. Under specific catalyst and reaction conditions, benzene and mesitylene can be controllably produced without anhydrous formation. The mesitylene selectivity is between 52% and 64%, and the product composition is stable. This method avoids the problem of acidic water formation caused by using methanol as a raw material, thus improving production efficiency and reducing production costs.

The utility model discloses a separation and purification device for durene, which relates to the technical field of durene production and comprises a purification tank, a support column is arranged at the lower end of the purification tank, a feed port is arranged at the top end of the purification tank, and a purification component and a stirring component are arranged in the purification tank. The purification assembly and the stirring assembly are both fixed on a top plate of the purification tank, a crystal scraping assembly is arranged on the purification assembly, and a discharging assembly is arranged at the lower end of the purification assembly. Through mutual cooperation of the first scraping assembly, the second scraping assembly and the discharging assembly, the problems that an existing durene separation and purification device is difficult in material taking, meanwhile, durene has toxicity, the danger of manual material taking is high, and the practicability of the device is poor are solved.

The invention provides an amorphous silica-alumina solid acid catalyst as well as a preparation method and application thereof, in particular to a method for preparing durene by adopting a sanding method, and relates to the technical field of catalysis and organic synthesis. The preparation method comprises the following steps: mixing an amorphous silicon source, a soft template agent, a growth inhibitor, hexadecyl trimethyl ammonium bromide and water; mixing organic aluminum with an organic solvent; and mixing the two obtained mixed solutions, carrying out hydrothermal crystallization, and carrying out solid-liquid separation, drying and roasting to obtain the amorphous silica-alumina solid acid catalyst. The solid acid catalyst synthesized in situ is rich in L acid, large in specific surface area, stable in active center, rich in mesopores and high in catalytic performance. The invention provides a method for preparing durene by adopting a sanding method. The conversion rate of unsym-trimethylbenzene and the yield of durene are high; by further utilizing the excellent mass transfer and heat transfer capabilities of the microreactor and combining the characteristics of heterogeneous catalysis and easy separation of the solid catalyst, the reaction rate is remarkably increased, the reaction time is shortened, and the reaction yield is increased.

A fuel composition comprising: (i) a gasoline base fuel comprising durene at a level of at least 1.5% by weight based on the weight of the fuel composition; and (ii) an ionic or non-ionic oil-soluble polar organic nitrogen-containing compound capable of acting as a wax crystal growth inhibitor in a gasoline base fuel. The fuel composition of the present invention makes it possible to increase the durene level in the fuel composition while reducing the crystallization problems associated with durene.

The invention provides a catalyst containing a ZSM-50 / MOR eutectic molecular sieve as well as a preparation method and application of the catalyst. The catalyst comprises a ZSM-50 / MOR eutectic molecular sieve, a binder, a metal active component and a non-metal auxiliary agent. The preparation method of the catalyst comprises the following steps: mixing and molding the ZSM-50 / MOR eutectic molecular sieve and the binder, then dipping in a precursor solution of the non-metal additive, then dipping in a precursor solution of the metal active component, and then activating and reducing to obtain the catalyst containing the ZSM-50 / MOR eutectic molecular sieve. The catalyst disclosed by the invention is applied to isomerization synthesis of durene from tetramethylbenzene, so that the reaction efficiency can be greatly improved, the conversion rate of durene and tetramethylbenzene and the selectivity of durene are remarkably improved, and the yield of durene is improved.

The invention provides a vanadium-titanium-phosphorus oxide catalyst prepared from an ionic liquid additive as well as a preparation method and application of the vanadium-titanium-phosphorus oxide catalyst, and belongs to the technical field of catalyst preparation. The preparation method comprises the following steps: fully and uniformly mixing an ionic liquid aqueous solution, respectively dipping the ionic liquid aqueous solution and an active component on a carrier, and drying and calcining after dipping to obtain the supported composite metal oxide catalyst. The catalyst provided by the invention is simple in preparation process and low in cost, and when the catalyst is applied to production of pyromellitic dianhydride from durene, the characteristics of high space velocity, high activity, short residence time, small catalyst dosage, simple reaction, one-step realization and the like can be realized. The catalyst has excellent catalytic performance in durene oxidation reaction, and is suitable for industrial application.

The invention provides a tetramethylbenzene isomerization catalyst and a preparation method and application thereof.The preparation method comprises the steps that an MCM-22 molecular sieve is subjected to first activation treatment with alkali liquor, MCM-22 seed crystals and crystallization alkali liquor are obtained, the MCM-22 seed crystals, sodium metaaluminate and silica sol are mixed and then subjected to extrusion molding treatment, a to-be-crystallized carrier is obtained, and the to-be-crystallized carrier is obtained; then mixing the to-be-crystallized carrier with crystallization alkali liquor to obtain a to-be-crystallized raw material, sequentially performing crystallization treatment, roasting treatment and ammonium exchange treatment on the to-be-crystallized raw material to obtain a carrier, and finally performing metal salt dipping treatment on the carrier to obtain the tetramethylbenzene isomerization catalyst. The tetramethylbenzene isomerization catalyst prepared by adopting the method has a through pore channel structure, relatively high crystallinity and catalytic activity, and can improve the yield and selectivity of durene when the durene and the tetramethylbenzene are subjected to catalytic treatment.

The utility model discloses novel equipment for separating durene through freezing crystallization, which relates to the field of durene preparation and comprises a workbench, the inner side of the workbench is connected with a pressure plate through an air cylinder, and the inner side of the workbench is further provided with a collecting box and a lifting mechanism arranged on the pressure plate and the collecting box in a sliding manner through a sliding rail; the lifting mechanism comprises a lifting unit and a filtering unit. By arranging the lifting mechanism, the collecting box and the filter screen box can be moved to the position below the pressing disc through the guide rail, materials in the filter screen box are extruded and squeezed through the pressing disc, solid and liquid of the materials are separated, the separated liquid is transferred into the collecting box through the filter screen box, separation is completed, and after the pressing disc is reset, the materials can be conveniently collected. Supporting blocks distributed on the two sides are in butt joint with butt joint blocks, the filter screen box is lifted to be separated from the collecting box, the materials can be conveniently separated from the filter screen box under the gravity effect, follow-up squeezing work is facilitated, and the working efficiency is further improved.

The invention discloses a durene centrifugal buffer stock bin with a spiral conveying cavity, which belongs to the technical field of durene conveying and comprises a base, a cyclone cylinder for centrifugally separating durene gas-solid mixture, the spiral conveying cavity for hermetically conveying materials, a spiral conveying rod and a motor. The closed spiral conveying cavity with the spiral conveying rod is integrated at the bottom of the stock bin, material buffering between upstream and downstream procedures can be achieved, closed quantitative conveying of materials can be achieved through forced pushing of the spiral conveying rod, in addition, in the using process, the rotary wall scraping mechanism and the bin body shaking mechanism are controlled to operate through mechanical linkage, and the material conveying efficiency is improved. A scraping plate in the rotary wall scraping mechanism rotates along the inner wall of the bin body to continuously remove hanging materials adhered to the bin wall and avoid material accumulation and hardening, an eccentric wheel in the shaking mechanism is in transmission fit with an elastic supporting piece to drive the bin body to generate high-frequency small-amplitude shaking, and a bridging structure formed by the materials in the bin is rapidly broken.