219results about "Lactams preparation" patented technology

The invention relates to the field of caprolactam production, and discloses a green and efficient production process and device. The process comprises the following steps: continuously oximating cyclohexanone and hydroxylamine in a microreactor under the catalysis of mesoporous silica solid acid; carrying out gas phase rearrangement on cyclohexanone-oxime in the presence of a ZSM-5 molecular sieve under the assistance of microwaves; coupling, rectifying and purifying the crude product through a four-stage molecular sieve membrane; and performing catalytic cracking on the by-product to obtain N2 / H2O and recycling. The device comprises a micro-reaction unit, a microwave-radial reactor, a membrane coupling rectifying tower group and a tail gas cracking unit. Zero emission of ammonium sulfate is achieved, the product purity is larger than or equal to 99.95%, and energy consumption is reduced by 45%.

Disclosed is a process for hydrolytic depolymerization of a polyamide contained in a chemical feedstock F, wherein the process comprises: providing the chemical feedstock F; providing a liquid aqueous stream SW; preparing a mixture comprising the raw material F and the liquid aqueous stream SW and subjecting said mixture to polyamide 6 depolymerization conditions in a chemical reaction unit UR, thereby obtaining an aqueous stream SE exiting the UR, the stream SE comprising epsilon-caprolactam, wherein the mixture to be subjected to polyamide 6 depolymerization conditions comprises polyamide 6 and further comprises polyethylene terephthalate and polyamide 6.6 in a mass ratio rS = (mPA6.6 + mPET) / mPA6, wherein 0.01 < = rS < = 2.5.

A process for preparing a liquid high-purity ε-caprolactam stream ST, comprising preparing a liquid stream SC comprising ε-caprolactam, said preparing comprising depolymerizing a material M comprising polyamide 6, said liquid stream SC further comprising one or more oxidizable organic impurity compounds X, wherein the stream SC has an ε-caprolactam purity ΩGC(SC) of at least 99 %; providing a stream SO comprising at least one permanganate; preparing an oxidation reaction educt mixture MOE from the stream SC and the stream SO, and subjecting the mixture MOE to oxidation reaction conditions, obtaining an oxidation reaction product stream SP comprising ε-caprolactam, further comprising one or more oxidation products Y obtained from the oxidation of at least a part of the one or more compounds X, and optionally further comprising a part of the one or more organic compounds X; separating at least a part of the one or more oxidation products Y and optionally at least a part of organic compound X from the stream SP, obtaining the stream ST exhibiting an ε-caprolactam purity ΩGC(ST) of at least 99.5 % with ΩGC(ST) > ΩGC(SC), and an APHA value ΩGC(ST) of at most 10.

The present invention belongs to the technical field of petrochemical catalysis, and relates to a preparation method for improving the stability of a Cu-Beta zeolite catalyst for preparing caprolactam from caprolactone, and the use thereof. In the present invention, a cavity-modified dealuminated Beta zeolite is used as a carrier, and copper is loaded in pore channels of the zeolite carrier by means of an improved ammonia distillation method. The cavity modification refers to subjecting the dealuminated Beta zeolite carrier to a desiliconization technique controlled by the use of a weak organic base so as to enlarge silanol nests generated by dealumination of the dealuminated Beta zeolite carrier, thereby better accommodating and stabilizing the nano and sub-nano copper particles. The core of the improved ammonia distillation method involves impregnating a zeolite carrier with an equal volume of a copper-ammonia complex solution, such that the copper-ammonia complex mainly undergoes, during ammonia distillation, a reaction of depositing copper hydroxide in zeolite pore channels, thereby improving the sintering resistance. The Cu-Beta catalyst prepared using the method provided by the present invention exhibits high activity, selectivity and stability when applied to the reaction of caprolactam prepared from caprolactone via gas-solid phase hydroamination.

The utility model discloses a simple continuous flow microreactor device with replaceable packing. The simple continuous flow microreactor device comprises a liquid pipeline system, a gas pipeline system, a microreactor and a cooling and product collecting system, the micro-reactor is a filler type micro-reaction tube, the filler type micro-reaction tube comprises a tube body, the tube body is filled with a replaceable porous filler, and the porous filler has both a microporous structure and a mesoporous structure; filtering sieve plates for intercepting porous fillers with different sizes are respectively arranged at the upper end and the lower end of the pipe body, and are respectively connected with the material inlet and outlet joint through fixing pieces for stabilizing the fillers; a blade ring and a sealing ring are sequentially arranged between the fixing piece and the pipe body from top to bottom. The microreactor disclosed by the utility model is applied to preparation of amide compounds, and compared with a conventional microreactor, the microreactor disclosed by the utility model can obtain higher product yield.

The present invention provides a method for recovering ε-caprolactam and polyether polyurethane from a material comprising nylon 6 and polyether polyurethane in a plant, wherein the plant comprises a separation section [B], a depolymerization section [C], a recovery section [D], and a purification section [E].

The present application belongs to the technical field of recycling of waste textiles, and particularly relates to a method for recycling waste nylon textiles, comprising: mechanically crushing the waste nylon textiles to obtain nylon fragments; mixing the nylon fragments, polyacrylic acid, metal or its compound, and then, under inert atmosphere and stirring, heating to 60-120 DEG C for 0.5-2 hours, and then, continuously heating to 220-300 DEG C, and catalytically depolymerizing under 1-5 MPa to obtain depolymerate; wherein the metal element of the metal or its compound is a metal having coordination ability with carbonyl; purifying the depolymerate to obtain caprolactam. The present application uses one-step mixing and two-step heating process, and the catalyst exists in the form of coexistence of metal coordination sites and carboxyl, so that the catalyst simultaneously plays the metal coordination activation role and the amide bond breaking and exchange reaction participated by carboxylic acid in the depolymerization process, forming a synergistically promoted efficient depolymerization mechanism, and effectively improving the efficiency of catalytic depolymerization.

The invention relates to the technical field of chemical engineering, and discloses an amide oil separation and ammonium sulfate crystallization integrated device. Comprising a neutralization reactor, a settling separation tank, a pre-crystallization solution tank, a DTB crystallizer, a centrifugal machine, a settling separator, a dryer, a mother liquor tank, a condensate water tank, an amide oil decanter, an ammoximation tert-butyl alcohol tower reboiler, a mother liquor heater set, a condenser, a vacuumizing condensing unit, a stirrer set and a reactor circulating pump. The invention further comprises a process for preparing the large-particle ammonium sulfate crystal from the saturated amide oil solution, rearrangement liquid from a lactam rearrangement system and gas ammonia are added into a neutralization reactor through an external circulation pipeline, and the large-particle ammonium sulfate crystal is prepared by fully utilizing heat in the gas ammonia dissolution and neutralization reaction and crystallization process. By combining the compound additive, the seed crystal and the continuous crystallization technology, the generation of large-particle ammonium sulfate crystals is promoted, meanwhile, the crystallization process is optimized, an efficient amide oil separation and continuous crystallization mode is realized, the energy consumption is saved, and the production efficiency is improved.

The present disclosure relates to a hierarchical porous titanosilicate molecular sieve containing framework titanium and anatase and a preparation method and application thereof. The titanosilicate molecular sieve has Ti 2p 3 / 2 XPS characteristics: the titanosilicate molecular sieve has spectral peaks at binding energy N1 and N2 positions; wherein the N1 is 459.2±0.2ev, the spectral peak peak area of the titanosilicate molecular sieve at the binding energy N1 position is recorded as A1; the N2 is 460.5±0.5ev, the spectral peak peak area of the titanosilicate molecular sieve at the binding energy N2 position is recorded as A2; X1 defined as below formula (1) is any value between 0.8-2.2ev: X1=N2-N1 formula (1); X2 defined as below formula (2) is any value between 0.1-0.8: X2=A2 / A1 formula (2). The present disclosure can exert the synergistic effect of framework titanium and anatase, can effectively improve the conversion rate of cyclohexanone oxime and the selectivity of caprolactam in the gas phase Beckmann rearrangement reaction of cyclohexanone oxime, and prolong the catalyst life.

The invention provides a preparation method and application of a solid acid catalyst for cyclohexanone-oxime gas phase rearrangement, and the method comprises the following steps: in the presence of a solvent, mixing and stirring a silicon source, an amine modifier and an activator for reaction; mixing the obtained reaction liquid with an acid treatment agent, and stirring while keeping the temperature; after heat preservation is finished, adding a strong acid modifier, continuously sealing, preserving heat and stirring, and after heat preservation is finished, evaporating the solution to dryness to obtain a catalyst precursor; and roasting the catalyst precursor to obtain the strongly acidic solid acid catalyst. The catalyst has good catalytic performance in the reaction process of preparing caprolactam through cyclohexanone-oxime gas phase rearrangement, the cyclohexanone-oxime conversion rate is high, caprolactam selectivity is high, impurities are few, the service life of the catalyst is long, generation of ammonium sulfate in a traditional technology is avoided, economic benefits are good, cost is low, and the catalyst is environmentally friendly.

The present invention provides a boron-containing Beta zeolite, a preparation method thereof and an application thereof, belonging to the field of catalyst preparation. The boron-containing Beta zeolite provided by the present invention contains silicon element and boron element; the molar ratio of silicon element to boron element in the boron-containing Beta zeolite is 15-60:1. The boron element introduced in the boron-containing Beta zeolite and the adjustment of the silicon-boron ratio in the present invention reduce the high-temperature acid sites and increase the low-temperature acid sites, thereby reducing the temperature of the Beckmann rearrangement reaction, reducing the synthesis of by-products, and improving the selectivity of cyclohexanone oxime. The results of the examples show that the selectivity of cyclohexanone oxime is 82.8-99.2% when the boron-containing Beta zeolite of the present invention is used for catalysis.

The present invention provides a process for recovering ε-caprolactam and polyether polyurethane from nylon 6 and polyether polyurethane comprising material in a plant, wherein the plant comprises a separation section [B], a depolymerization section [C], a recovery section [D], and a purification section [E].

The present invention relates to a method for preparing a mixture containing cyclohexanol and cyclohexanone, comprising the step of hydrogenating cyclohexyl hydroperoxide in cyclohexane in the presence of a Raney nickel catalyst to obtain cyclohexanol and cyclohexanone.

A method of depolymerizing a polyamide is provided. In some embodiments, the method includes combining a polyamide and an alkali metal catalyst to depolymerize the polyamide to a product, where the alkali metal catalyst is selected from catalysts having the formula MXRn, where M is an alkali metal, X is H, C, N, Si or Sn, R is independently selected from hydrogen, alkyl, silyl, and aryl, and n is 0-2.

This disclosure relates to a process for the synthesis of a compound of formula (I): (I) wherein w, x, y, and z are as defined in the description. The process includes the reaction of a compound of formula (II): (II) with carbonyldiimidazole, and the reaction of the resulting compound with propargylamine.

The present invention provides an improved process for recovering ε-caprolactam from multicomponent materials, in particular multilayer films, comprising nylon 6. Furthermore, the present invention provides a plant adapted to carry out the process of the present invention, and recovered ε-caprolactam obtainable by the process of the present invention, having a product carbon footprint of less than 2.5 kg CO2 equivalent per kg purified ε-caprolactam (based on Eco Invent version 3.7.1 (region: Europe) data).

This invention relates to the field of caprolactam preparation technology, specifically a method for preparing a porous perfluorosulfonic acid resin catalyst and its application in the liquid-phase Beckmann rearrangement to produce caprolactam. The method uses cyclohexanone oxime as a raw material, and one or more of isopropanol, n-butanol, acetonitrile, formamide, acetone, dioxane, tetrahydrofuran, ethyl acetate, N,N-dimethylformamide, and dimethyl sulfoxide as solvents. The porous perfluorosulfonic acid resin is used as the catalyst. The molar ratio of solvent to cyclohexanone oxime is (2-10):1, and the catalyst content is 0.1-0.5%. The reaction is carried out in a batch reactor under mechanical stirring, with a reactant residence time of 1-5 hours, a reaction temperature of 90-110°C, and a slightly positive pressure. After the reaction, the conversion rate of cyclohexanone oxime is ≥50%, dimethyl sulfoxide does not participate in the reaction, and the selectivity of caprolactam is ≥99%.

The present invention relates to a process for recovering epsilon-caprolactam from a nylon 6-containing multi-component material. The present invention provides an improved process for the recovery of epsilon-caprolactam from nylon 6-containing multi-component materials, in particular multilayer films. Furthermore, the invention provides: a plant configured to carry out the method of the invention; and the recovered [epsilon]-caprolactam obtainable by the process of the invention having a product carbon footprint of less than 2.5 kg CO2 equivalents per kg of purified [epsilon]-caprolactam.

The application provides a purification process method and device of a lactam, wherein an oxime is subjected to a rearrangement reaction with a catalyst, the obtained lactam is purified after the rearrangement reaction, and the method comprises the following steps: extracting the lactam by using an extraction solvent to obtain a lactam solution from which the catalyst is separated, performing alkali washing and water washing on the obtained lactam solution to obtain a lactam solution after alkali washing and water washing, performing hydrogenation reaction on the obtained lactam solution again, performing crystallization separation on the lactam solution after hydrogenation to obtain a lactam product crystal, and then performing treatment on the obtained lactam product crystal by means of solvent washing, rectification, distillation or crystallization to obtain the lactam with a purity of greater than or equal to 99.9%.

To provide a method for manufacturing a cyclic lactam that can manufacture the cyclic lactam with high selectivity, and a device for manufacturing a cyclic lactam. A method for manufacturing a cyclic lactam, the method including performing a depolymerization reaction by using 1 part by mass or more of a polyphosphoric acid per 100 parts by mass of a polyamide resin containing a repeating unit represented by Formula (a). In Formula (a), n1 is an integer of 3 to 22, and n1 may be a different value for each of the repeating unit.

A process for hydrolytically depolymerizing polyamide 6 prepared from ε-caprolactam, the process comprising (i) providing a chemical feedstock F comprising the polyamide 6 and further comprising at least one further organic polymeric compound; (ii) providing a liquid aqueous stream Sw; (iii) admixing the feedstock F with the stream Sw and subjecting the obtained mixture to polyamide 6 depolymerization conditions in a reaction unit UR, obtaining an aqueous stream SE comprising ε-caprolactam and one or more decomposition products of one or more of the at least one further organic polymeric compound; (iv) generating an aqueous stream SR comprising at least part of the water and at least part of at least one of the one or more decomposition products comprised in the stream S, said stream SR; (v) feeding at least part of the aqueous stream SR back to the chemical reaction unit UR.

The invention provides a photochemical reactor with a total reflection characteristic, a method and a system, and relates to the technical field of photochemistry. According to the invention, the light source is aligned with the direction of the reaction fluid, and the light energy is restrained in the reaction system by utilizing the total reflection condition, so that an optical waveguide structure which is propagated in order is formed, and the problem of serious loss caused by disordered light energy scattering, device wall absorption and transmission in the prior art is fundamentally solved. And due to the ordered and efficient utilization of light energy, the reaction rate is higher under the same light intensity, or higher light intensity can be used under the small pipe diameter, so that the reaction efficiency is greatly improved, and the reaction time is shortened. The structure of the reactor is only a simple tubular structure, no complex optical fiber coupling or nesting channel is needed, linear amplification can be achieved through simple series connection or parallel connection, and no obvious bad amplification effect exists. The two total reflection modes can be flexibly selected to adapt to reaction systems with different refractive indexes, the applicability is wide, the structure is simple, the energy consumption is low, and the requirements of green chemistry are met.

The invention relates to the field of production of caprolactam by Beckmann rearrangement of cyclohexanone-oxime, and discloses a gasification method and system of cyclohexanone-oxime. The method comprises the following steps: gasifying a circulating cyclohexanone oxime liquid phase, inert gas and a first solvent in a gasifier, and then carrying out gas-liquid separation to obtain a first gas-phase material and a liquid-phase material; (2) returning part of the liquid-phase material to the gasifier for gasification; (3) mixing the rest of the liquid-phase material with a second solvent to obtain a mixed solution; then feeding the mixed solution to a fluidized bed to be in contact with solid particles for secondary gasification to obtain solid particles attached with heavy substances and a second gas-phase material; carrying out Beckmann rearrangement reaction on the first gas-phase material and the second gas-phase material; wherein the temperature of the solid particles is at least 20 DEG C higher than that of the mixed liquid. The method provided by the invention can reduce the throwing amount of heavy impurities, improve the utilization rate of cyclohexanone-oxime, reduce the unit consumption of cyclohexanone-oxime, and improve the activity and service life of the catalyst.

This invention discloses a kinetically controlled method for preparing hierarchical porous molecular sieves, belonging to the field of catalyst preparation technology. It employs a two-step crystallization method: first, nucleation occurs at low and ultra-low H2O / SiO2 molar ratios; then, after the low-temperature phase, water is added, followed by rapid growth at high temperature and high H2O / SiO2 molar ratios. The solid-phase and liquid-phase crystallization mechanisms in the synthesis system work in succession to prepare hierarchical molecular sieves. This invention, without adding any mesoporous pore-forming agents, only modulates the crystallization temperature and the H2O / SiO2 molar ratio of the synthesis system to kinetically control the crystallization mechanism, resulting in molecular sieves with higher catalytic performance than those obtained using traditional methods. Furthermore, it overcomes the drawbacks of traditional hierarchical porous molecular sieve preparation processes, such as high cost, high calcination energy consumption, poor mesopore connectivity, and severe contamination from pore-forming agents.

The invention relates to the technical field of catalysts, and discloses a ZSM-5 type structure-containing all-silicon molecular sieve catalyst and a preparation method thereof, and a cyclohexanone-oxime gas phase Beckmann rearrangement reaction method, the method comprises the following steps: (1) mixing a silicon source, KOH, an organic alkali and water, and hydrolyzing to obtain a colloid mixture; (2) crystallizing the colloid mixture, and optionally concentrating the obtained crystallization mother liquor to obtain molecular sieve slurry; (3) mixing the molecular sieve slurry with a binder, and pulping to obtain molecular sieve-binder slurry; carrying out spray molding on the molecular sieve-binder slurry, and then roasting; and (4) contacting the product obtained by roasting in the step (3) with an alkaline buffer solution containing ammonium salt, ammonia water, magnesium salt and bromine salt, and then drying. The microsphere type all-silicon-1 molecular sieve catalyst prepared by the method has relatively high cyclohexanone-oxime conversion rate and caprolactam selectivity.

The application relates to the field of molecular sieves, and discloses a ZSM-5 molecular sieve, a preparation method and application thereof, and a catalytic cracking method of triisopropylbenzene. The ZSM-5 molecular sieve has a cross-assembled aggregate crystal morphology formed by sheet-shaped nanocrystals, and the sheet-shaped nanocrystals adjacent to each other in the molecular sieve have a cross-assembled aggregate crystal morphology formed by 90 DEG + / -10 DEG rotation symbiosis and 30 DEG + / -5 DEG rotation symbiosis.

The present application relates to the technical field of polymer material chemical recycling, and in particular to a kind of nano-enzyme catalyst and process for its use in hydrothermal method degradation polycaprolactam.The nano-enzyme catalyst provided by the present application uses specific single metal or double metal combination as metal center, and is combined with specific organic ligand, can be efficiently and deeply degraded PA6 at relatively low temperature, and the catalyst can also be recycled, completely realizing the green recycling of PA6.The nano-enzyme catalyst provided by the present application can make the conversion rate of PA6 molecule reach 100% using hydrothermal method, and the caprolactam yield can be stably above 94%, avoiding the use of organic solvent with high toxicity, and realizing the whole green recycling from " waste containing PA6" to " renewable caprolactam monomer".

The application provides a photochemical reactor, method and system with total reflection characteristics, and relates to the technical field of photochemistry.The application aligns a light source with the direction of a reaction fluid, and uses total reflection conditions to constrain light energy in a reaction system, thereby forming an orderly propagating optical waveguide structure, and fundamentally solving the problem of serious loss caused by disordered scattering of light energy, wall absorption and transmission in the prior art.Orderly and efficient use of light energy enables faster reaction rate under the same light intensity, or higher light intensity can be used under small pipe diameter, thereby greatly improving reaction efficiency and shortening reaction time.The reactor structure of the application is only a simple pipe structure, and does not need complex optical fiber coupling or nested channels, and linear amplification can be realized through simple series connection or parallel connection without obvious adverse amplification effect.Two total reflection modes can be flexibly selected to adapt to reaction systems with different refractive indexes, are widely applicable, and have simple structure and low energy consumption, and meet the requirements of green chemistry.

The present disclosure relates to a kind of multi-level hole pure silicon molecular sieve and its preparation method and cyclohexanone oxime catalytic reaction method.The multi-level hole pure silicon molecular sieve has the following diffusion coefficient characteristics: with cyclohexane as probe molecule, the diffusion coefficient of the probe molecule in the multi-level hole pure silicon molecular sieve is 0.015-0.02 μm 2 / min, measured by zero-length column method.The present disclosure can effectively improve the molecular diffusion performance of molecular sieve, and when the molecular sieve is used for cyclohexanone oxime gas phase Beckmann rearrangement reaction, the selectivity of caprolactam and the service life of catalyst can be effectively improved.

The present invention relates to a method for amorphizing a material comprising at least one polymer, comprising the following steps: a) adding the material to a solution S1 containing at least one salt and having a pH less than or equal to 7; b) exposing the solution S1 to a temperature T1 greater than or equal to 20°C; c) maintaining the material in said solution S1 until the polymer is amorphized; d) adjusting the pH of the solution S1 to a pH greater than or equal to 4 or transferring the material obtained into a solution S2 containing at least one salt and having a pH greater than or equal to 4 and in which the mass concentration of salt is greater than or equal to 10% by weight relative to the total weight of the solution S2.