519results about "Lactams preparation" patented technology

The present invention generally relates to processes for the chemocatalytic conversion of a carbohydrate source to an adipic acid product. The present invention includes processes for the conversion of a carbohydrate source to an adipic acid product via a furanic substrate, such as 2,5-furandicarboxylic acid or derivatives thereof. The present invention also includes processes for producing an adipic acid product comprising the catalytic hydrogenation of a furanic substrate to produce a tetrahydrofuranic substrate and the catalytic hydrodeoxygenation of at least a portion of the tetrahydrofuranic substrate to an adipic acid product. The present invention also includes products produced from adipic acid product and processes for the production thereof from such adipic acid product.

A MFI-molecular sieve catalyst for preparing caprolactam from cyclohexanone oxime by gas-phase Beckmann rearrangement is prepared through proportionally mixing MFI-molecular sieve with alkaline silica gel, shaping, drying and calcining. It has high conversion rate and selectivity.

This invention relates to a refine means of epsilon - caprolactam by separation and purification. The feature of the invention lay in that it includes the step of crystallize epsilon - caprolactam from ethereal solution containing crude epsilon - caprolactam.The product purity can reach 99.98%upwards, absorption value of potassium permanganate is greater than 10000 or more, the extinction value of epsilon - caprolactam at 290nm wavelength is 0.05 or smaller. The invention wholly meet the require of industrial product.

The present invention generally relates to processes for the chemocatalytic conversion of a glucose source to an adipic acid product. The present invention includes processes for the conversion of glucose to an adipic acid product via glucaric acid or derivatives thereof. The present invention also includes processes comprising catalytic oxidation of glucose to glucaric acid or derivative thereof and processes comprising the catalytic hydrodeoxygenation of glucaric acid or derivatives thereof to an adipic acid product. The present invention also includes products produced from adipic acid product and processes for the production thereof from such adipic acid product.

The present invention relates to a method and catalysts for the stereoselective addition of a nucleophile to a reactive π-bond of a substrate. The chiral, non-racemic catalysts of the present invention constitute the first examples of catalysts for nucleophilic additions that comprise a main-group metal and a tri- or tetra-dentate ligand.

A process for producing epsi-caprolactam is provided which comprises the steps of subjecting cyclohexanone oxime to a gaseous phase Beckmann rearrangement reaction in a fluidized bed system using a solid catalyst and re-generating the catalyst, wherein said process comprises a step of treating the catalyst with an oxygen-containing gas at an elevated temperature in a re-generation step so that the nitrogen content of the catalyst falls within a range of 10 ppm to 2,500 ppm on its way to the reaction step from the re-generating step. According to the present invention, epsi-caprolactam is produced with a high conversion or a high selectivity without interrupting the rearrangement reaction or the re-generation step.

The invention provides a method for producing caprolactam by taking high-purity benzene as a raw material, and the method comprises the following steps of: A. preparing cyclohexene from the raw material benzene through hydrogenation; B. separating and purifying cyclohexene; C. carrying out hydration on the cyclohexene for preparing cyclohexanol; D. separating and purifying cyclohexanol; E. carrying out dehydrogenation on cyclohexanol for preparaing cyclohexanone; F. refining cyclohexanone; G. carrying out oximation on cyclohexanone so as to prepare cyclohexanone-oxime; H. refining cyclohexanone-oxime; I. carrying out rearrangement on refined cyclohexanone-oxime so as to prepare caprolactam; and J. refining caprolactam, wherein the high-purity benzene is adopted as a raw material, so that the purity of benzene is more than 99.95%, the sulphur content is less than 5ppm, and the methylbenzene is not more than 100ppm. The method has the beneficial effects that the high-purity benzene is adopted as a raw material, so that the impurity is less, and the product quality is high; the raw material is high in comprehensive utilization rate and low in hydrogen consumption; and the mass of the raw material and intermediate products generated in all the steps of reaction can be strictly controlled, so that the direct commercial value of the intermediate products is fully exerted, and the optimal quality of the product caprolactam can be reached.

A high-silica content zeolite having a novel crystal structure, a zeolite membrane and manufacturing methods for these are provided, and the present invention relates to a zeolite having the chemical composition represented by [(Si_36-xT_y.O₇₂).M_z] (wherein M is a cation of an alkali metal such as Li, Na, K or Rb, T represents Al, Ga, Fe and Ce as skeleton substituting elements, x satisfies 0≦x≦3.0, y satisfies 0≦y≦1.0 and z satisfies 0≦z≦3.0), and having a micropore formed of covalent bonds between Si and O atoms, with a specific diffraction peak at 2θ in powder x-ray diffraction, together with a zeolite membrane and methods for manufacturing these.

A process for producing a pentacyl-type crystalline zeolite is provided which comprises the steps of (i) preparing a mixture of a silicon compound, water and tetrapropyl ammonium hydroxide, (ii) conducting a hydrothermal reaction of the mixture to obtain a reaction mixture containing zeolite crystals, (iii) separating zeolite crystals from the reaction mixture to collect a remaining solution, (iv) calcinating the resulting zeolite crystals, (v) treating the calcinated zeolite crystals with a solution such as ammonia water and (vi) recycling the solution collected in step (iii) to step (i), wherein in the mixture prepared in step (i) a molar ratio of hydroxide ion to silicon is from about 0.1 to about 0.4 and a molar ratio of potassium to silicon is about 0.1 or less. With this process, a zeolite catalyst having good performance can be produced with good reproducibility.

The process of preparing caprolactam with cyclohexanone oxime includes the vapor Beckmann rearrangement reaction of cyclohexanone oxime inside one first fixed bed reactor in the presence of MFI structure molecular sieve catalyst; the decomposition and conversion of the reaction side product O-alkyl-epsilon-caprolactim into caprolactam inside one second fixed bed reactor in the presence of MFI structure molecular sieve catalyst and water; and the separation and purification of the reaction effluent. Compared with single vapor Beckmann rearrangement reaction process of cyclohexanone oxime, the present invention has 1-3 % raised caprolactam yield.

The invention provides a nanometer all-silicon molecular sieve. The nanometer all-silicon molecular sieve is prepared from tetrapropylammonium hydroxide, a silicon source, water and amino acids. A mole ratio of the silicon source to tetrapropylammonium hydroxide to water is 1: [0.05 to 0.50]: [15 to 65]. The mass of the used amino acids is 0.5 to 5% of that of the silicon source. A mole number and a mass number of silica represent a mole number and a mass number of the silicon source. The invention also provides a preparation method of the nanometer all-silicon molecular sieve, and a use of the nanometer all-silicon molecular sieve in a cyclohexanone-oxime gas phase beckmann rearrangement reaction. The nanometer all-silicon molecular sieve has a high degree of crystallization, regular morphology and adjustable particle sizes of 40 to 160 nanometers. In a cyclohexanone-oxime gas phase beckmann rearrangement reaction, the nanometer all-silicon molecular sieve shows excellent catalytic activity, selectivity and stability.

The invention provides an all-silicon molecular sieve and a synthetic method thereof. Q4/Q3 of the all-silicon molecular sieve is (10-90):1, wherein Q4 is the peak intensity expressed by the peak height at the chemical shift of -112+/-2ppm in a 29SiNMR spectrogram of the all-silicon molecular sieve, and Q3 is the peak intensity expressed by the peak height at chemical shift of -103+/-2ppm in the 29SiNMR spectrogram of the all-silicon molecular sieve. The synthetic method of the all-silicon molecular sieve comprises the following steps: mixing a template agent, an organic silicon source, an inorganic ammonium source and water to be subjected to hydrolytic alcohol removal, aging the obtained product, mixing the aging product with a solid silicon source, crystallizing the mixture in a closed reaction kettle, and recovering the all-silicon molecular sieve. The all-silicon molecular sieve provided by the invention has higher activity in cyclohexanone-oxime beckmann rearrangement.

Processes to prepare 5-cyanovaleric acid or its ester are provided, by carbonylation of a pentenenitrile, wherein pentenenitrile is reacted with carbon monoxide and water and/or an alcohol in the presence of a catalyst system. The catalyst system contains:

• • (a) a metal of Group VIII or a compound thereof and
  • (b) a bidentate phosphine, arsine and/or stibine ligand, wherein the bidentate ligand has the general formula (I):

R¹R²-M¹-R-M²-R³R⁴  (I)

 wherein M¹ and M² are independently P, As or Sb, R is a divalent organic bridging group, which bridging group comprises a chain of 3 to 5 atoms directly connecting the 2 phosphorus atoms, which chain consists of carbon atoms and optionally a nitrogen, oxygen or sulphur atom or a silano or dialkylsilicon group, which alkyl groups independently comprise from 1 to 4 carbon atoms, and R¹–R⁴ represent the same or different optionally substituted tertiary alkyl groups,

(c) an acid having a pKa less than 3, as measured at 18° C. in an aqueous solution.

ε-caprolactam is also prepared by reduction of 5-cyanovaleric acid or ester obtained above to 6-aminocaproic acid or ester, and then cyclisation of the 6-aminocaproic acid or ester to ε-caprolactam.

The invention provides a method for preparing caprolactam through gas phase Beckmann rearrangement of cyclohexanone-oxime gas. According to the method, under the condition of rearrangement reaction, cyclohexanone-oxime is in contact with a catalyst, and the catalyst is obtained by the steps of forming a molecular screen with an aluminum-free MFI (Melt Flow Index) structure, and enabling the molecular screen to be in contact with an alkaline buffer solution of a nitrogen-containing compound. The method is high in cyclohexanone-oxime conversion rate, and is capable of realizing long-period and continuous production; the selectivity of caprolactam is capable of reaching 95.8 percent.

The invention relates to a preparation method for a catalyst containing a MFI structure zeolite. The method is characterized in that: raw materials comprising the MFI structure zeolite and alkaline silica sol are subjected to mixing, forming, drying and baking to obtain a baked product, then the baked product contacts a alkaline buffer solution of a nitrogen compound, wherein a pH value of the alkaline silica sol is 9-11, a weight ratio of the MFI structure zeolite to the alkaline silica sol (according to a SiO2 content) is 1-50:1.

A curable coating composition, and process of application thereof, particularly useful as a clearcoating applied over a pigmented basecoat that has significantly decreased VOC and improved scratch, etch, and mar resistance, is provided in accordance with the present invention, which is contains a silane functional oligomeric or polymeric material comprising carbamate groups and a crosslinking component comprising groups that are reactive with the carbamate groups.

The invention relates to a method for synthesizing cyclohexanone-oxime and caprolactam, particularly a method for synthesizing cyclohexanone-oxime and caprolactam by performing catalytic hydrogenation on nitrocyclohexane used as a raw gas phase. The method has the advantages of high controllability, low cost, environmental protection, higher conversion ratio of raw materials and higher yield, and has industrialization application prospects. The reaction process is simple, no coproduct ammonium sulfate is generated in the reaction process, and no wastewater or waste gas is generated to pollute the environment, and thus, the method is an environment-friendly production technique.

A method of producing epsilon -caprolactam from cyclohexanone in the gaseous phase using MFI catalysts on whose surface symmetrically arranged OH groups are present.

Provided herein are processes for preparing caprolactam from a starting material such as one or more of the cis,cis-, cis,trans- and trans,trans-double-bond isomers of muconamide, muconic acid ester, or muconic acid. The starting material, intermediates, and caprolactam prepared therefrom can contain carbon atoms derived from biomass containing detectable ¹⁴C content determined according to ASTM D6866 and optionally containing a ¹⁴C content up to 0.0000000001% (one part per trillion). Caprolactam so prepared can be used to make various polyamides.

The invention discloses a catalyst for producing caprolactam as well as a preparation method and application of the catalyst. The catalyst for producing the caprolactam is prepared by the following steps: synthesizing an MFI type zeolite molecular sieve; putting the MFI type zeolite molecular sieve into an nitrogen-containing organic alkali and organic silicon mixed water solution, and then carrying out a reaction at the temperature of 120-190 DEG C for 24-72 hours for modification treatment; mixing the zeolite molecular sieve treated by modification with a bonding agent, feeding a nitric acid solution into the mixture, kneading, molding, drying, and roasting to obtain the molecular sieve-based catalysts. After the zeolite molecular sieve is treated by the nitrogen-containing organic alkali combined with organosilane, the hydroxyl active center on the surface of the zeolite molecular sieve is effectively inhibited, so that the hydrophobicity of the catalyst is improved, and the reaction product caprolactam is rapidly diffused outside from pores of the catalyst; therefore, the side reactions of the caprolactam on the surface of the catalyst can be reduced, and the reaction activity, stability and product selectivity of the catalyst are improved.