192results about "Preparation by hydrogen cyanide addition" patented technology

A process for preparing a hydrocyanation catalyst comprising contacting a bidentate phosphorous-containing ligand with a molar excess of nickel chloride in the presence of a nitrile solvent and a reducing metal which is more electropositive than nickel. Preferably, the nickel chloride is dried before use.

Hydrocyanation reactions employing multidentate phosphite ligands and multidentate phosphite ligands are disclosed. The ligands have phenyl containing substituents attached to the ortho position of the terminal phenol group and/or attached to the ortho position of the bridging group. Catalyst compositions havng such ligands achieve 97% or greater distribution in hydrocyanation.

Supported bis(phosphorus) ligands are disclosed for use in a variety of catalytic processes, including the isomerization, hydrogenation, hydroformylation, and hydrocyanation of unsaturated organic compounds. Catalysts are formed when the ligands are combined with a catalytically active metal, such as nickel.

Multidentate phosphite ligands are disclosed for use in reactions such as hydrocyanation and isomerization. The catalyst compositions made therefrom and the various catalytic processes which employ such multidentate phosphite ligands are also disclosed. In particular, the ligands have heteroatom-containing substituents on the carbon attached to the ortho position of the terminal phenol group.

Nickel-metal-containing solids for use in manufacturing nickel metal complexes are disclosed. The nickel-metal-containing solids are made by reducing basic nickel carbonates. By varying the molar ratios of carbonates and bicarbonates to nickel salts, the methods provide basic nickel carbonates that produce superior nickel metal-containing solids that react more effectively with phosphorous-containing ligands. The phosphorous containing ligands can be both monodentate and bidentate phosphorous-containing ligands.

Multiphasic reactions, especially those reactions using a phase transfer catalyst, are conducted in microchannel apparatus. Advantageously, these reactions can be conducted with two, planar microlayers of reactants in adjacent laminar flow streams. Microchannel apparatus and methods for conducting unit operations such as reactions and separations in microchannel apparatus is also described. Microchannel apparatus can provide advantages for controlling reactions and separating products, solvents or reactants in multiphase reactions.

A process is described for preparing 3-pentenenitrile, characterized by the following process steps:

• (a) reacting 1,3-butadiene with hydrogen cyanide over at least one catalyst to obtain a stream 1 which comprises 3-pentenenitrile, 2-methyl-3-butenenitrile, the at least one catalyst and 1,3-butadiene,
• (b) distilling stream 1 in a column to obtain a high-1,3-butadiene stream 2 as the top product and a low-1,3-butadiene stream 3 as the bottom product which comprises 3-pentenenitrile, the at least one catalyst and 2-methyl-3-butenenitrile,
• (c) distilling stream 3 in a column to obtain a stream 4 as the top product which comprises 1,3-butadiene, a stream 5 which comprises 3-pentenenitrile and 2-methyl-3-butenenitrile at a side draw of the column, and a stream 6 as the bottom product which comprises the at least one catalyst,
• (d) distilling stream 5 to obtain a stream 7 as the top product which comprises 2-methyl-3-butenenitrile, and a stream 8 as the bottom product which comprises 3-pentenenitrile.

The invention provides a hydrocyanation process for the production of adiponitrile and other dinitriles having six carbon atoms, the process comprising:

• • a) forming a reaction mixture in the presence of at least one Lewis acid, said reaction mixture comprising ethylenically unsaturated nitrites having five carbon atoms, hydrogen cyanide, and a catalyst precursor composition, by continuously feeding ethylenically unsaturated nitrites, hydrogen cyanide, and a catalyst precursor composition;
  • b) controlling X and Z, wherein X is the overall feed molar ratio of 2-pentenenitriles to all unsaturated nitriles and Z is the overall feed molar ratio of hydrogen cyanide to all unsaturated nitrites, by selecting a value for X in the range from about 0.001 to about 0.5, and a value for Z in the range from about 0.5/1 to about 0.99/1, such that the value of quotient Q, wherein

is in the range from about 0.2 to about 10, wherein 3PN is 3-pentenenitriles and 4PN is 4-pentenenitrile; and

• • c) withdrawing a reaction product mixture comprising adiponitrile;
  • wherein the ratio of the concentration of 2-pentenenitriles to the concentration of 3-pentenenitriles in the reaction mixture is from about 0.2/1 to about 10/1;
  • wherein the catalyst precursor composition comprises a zero-valent nickel and at least one bidentate phosphite ligand; and

wherein the bidentate phosphite ligand is selected from a member of the group represented by Formulas I and 11 as described herein.

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.

The present invention relates to a process of hydrocyanation of ethylenically unsaturated organic compounds to compounds having at least one nitrile function, particularly the hydrocyanation of diolefins such as butadiene, or of substituted olefins such as alkene nitrites such as pentenenitriles; the subject hydrocyanation is carried out in the presence of a catalytic system comprising a metallic element and mono- and pluri-dentate organophosphorus ligands.

The invention provides a hydrocyanation process for the production of adiponitrile and other dinitriles having six carbon atoms, the process comprising:

• • a) forming a reaction mixture in the presence of at least one Lewis acid, said reaction mixture comprising ethylenically unsaturated nitriles having five carbon atoms, hydrogen cyanide, and a catalyst precursor composition, by continuously feeding ethylenically unsaturated nitriles, hydrogen cyanide, and a catalyst precursor composition;
  • b) controlling X and Z, wherein X is the overall feed molar ratio of 2-pentenenitriles to all unsaturated nitriles and Z is the overall feed molar ratio of hydrogen cyanide to all unsaturated nitriles, by selecting a value for X in the range from about 0.001 to about 0.5, and a value for Z in the range from about 0.5/1 to about 0.99/1, such that the value of quotient Q, wherein

is in the range from about 0.2 to about 10, wherein 3PN is 3-pentenenitriles and 4PN is 4-pentenenitrile; and

• • c) withdrawing a reaction product mixture comprising adiponitrile;
  • wherein the ratio of the concentration of 2-pentenenitriles to the concentration of 3-pentenenitriles in the reaction mixture is from about 0.2/1 to about 10/1;
  • wherein the catalyst precursor composition comprises a zero-valent nickel and at least one multidentate phosphorus-containing ligand;
  • wherein the multidentate phosphorus-containing ligand is selected from the group consisting of a phosphite, a phosphonite, a phosphinite, a phosphine, and a mixed phosphorus-containing ligand or a combination of such members; and
  • wherein the multidentate phosphorus-containing ligand gives acceptable results according to at least one protocol of the 2-Pentenenitrile Hydrocyanation Test Method.

A process to prepare substantially pure glycolonitrile in an aqueous medium is provided by reacting hydrogen cyanide and formaldehyde. The formaldehyde feed stream is heated prior to reacting with hydrogen cyanide, resulting in an aqueous glycolonitrile solution with fewer impurities, especially less unreacted formaldehyde, than is obtained by other methods. The process enables production of an aqueous glycolonitrile solution that requires less post-reaction purification (if any at all) prior to enzymatically converting the glycolonitrile into glycolic acid.

The invention discloses a method for preparing 3-cyan-3,5,5-trimethyl cyclohexanone. The method comprises the following steps of: taking isophorone as a raw material and adding hydrocyanic acid into the isophorone to perform addition reaction at the high temperature of between 100 and 200 DEG C under the action of an alkali catalyst to produce a crude product of the 3-cyan-3,5,5-trimethyl cyclohexanone; reducing the temperature to 80 to 120 DEG C, adding at least one organic acid serving as a neutralizer and a stabilizer into the reaction mixture and adding an organic solvent or a mixed solvent of the organic solvent and water into the reaction mixture; performing crystallization by cooling and filtering the mixture so as to obtain the finished 3-cyan-3,5,5-trimethyl cyclohexanone. The method can greatly reduce the production cost and has simple industrialized process and easy operation.

A method for the production of 2-hydroxy-4-(methylthio)butyronitrile having good storage stability in a multi-zone reactor, is provided. 3-methylmercaptopropionaldehyde is reacted with hydrogen cyanide in the presence of a base as catalyst in a main reaction zone of the multizone reactor to form a reaction mixture comprising the 2-hydroxy-4-(methylthio)butyronitrile, unreacted 3-methylmercaptopropionaldehyde, the catalyst and residual amounts of gaseous hydrogen cyanide. The residual gaseous hydrogen cyanide is removed from the main reaction zone to an absorption and post-reaction zone of the reactor which comprises a mixture of 3-methylmercaptopropionaldehyde and the catalyst; and the gaseous hydrogen cyanide is further reacted with the 3-methylmercaptopropionaldehyde in the absorption and post reaction zone. A molar ratio of hydrogen cyanide to 3-(methylthio)propanal in the main reaction zone is from 0.98 to 1.03.

The present invention is use of chiral oxazolinyl. The complex comprising 1-[2-(4S)-4-R-4.5-dihydro-2- oxazolinyl-ethyl]piperidine or 1-[2-(4S)-4-isopropyl-4.5- dihydro-2-oxazolinyl-ethyl] tetrahydropyrrole, and the chloride or diethylate of bivalent metal Zn, Cu, La or Sm is used as the chiral catalyst for the addition reaction between aromatic aldehyde, substituted aromatic aldehyde or butyl aldehyde and cyanide or nitrile to prepare chiral target product. In the addition reaction of para aromatic aldehyde, R-form as main target product may be obtained in the conversion rate higher than 80 %, and ee % greater than 97 %; and in other addition reaction, S-form as main target product may be obtained in the conversion rate higher than 80 %, and ee % greater than 99 %.

The invention provides a reactor for preparing isophorone nitrile and a method for continuously preparing the isophorone nitrile by adopting the reactor. A plurality of millimeter to micron-sized narrow regular reaction channels which are arranged in parallel are arranged in the reactor, and inner members are arranged in the reaction channels, so that the reactor has good heat and mass transfer effects, and the dwell time can be accurately controlled, thereby obtaining a high reaction conversion rate and a high product yield. Compared with a traditional batch reactor or a common continuous tubular reactor, the method has obvious advantages on many aspects of improvement in the reaction effect in preparation of the isophorone nitrile, safety in production, energy conservation, consumption reduction and the like.

A novel nickel particulate form is provided that efficiently forms a zero-valent nickel complex with a phosphorus-containing ligands in an organic liquid to form a hydrocyanation catalyst. Particles in the nickel particulate form comprise nickel crystallites. For example, the nickel particulate form can have a BET Specific Surface Area of at least about 1 m²/gm; an average crystallite size less than about 20-25 nm, the nickel particulate form can have at least 10% of the crystallites in the nickel form can have can have a diameter (C10) of less than about 10 nm, and/or there are on average at least about 10¹⁵ surface crystallites per gram nickel. A ratio of BET SSA to C50 for the nickel particulate form can be at least about 0.1×10⁹ m/gm and preferably at least about 0.4×10⁹ m/gm. Methods of preparation and use are also provided.

The invention concerns a hydrocyanation method for ethylenically unsaturated organic compounds in particular to obtain nitriles, and more particularly hydrocyanation of substituted diolefins or of olefins for producing dinitriles, and/or the isomerization of nitriles obtained by hydrocyanation. The invention more particularly concerns hydrocyanation catalysed by a nickel-based compound. Thus the catalyst used in said production method is treated in output with hydrogen cyanide to recover and re-dissolve the nickel precipitated in the form of nickel hydroxide. The method enables to regenerate and prolong the life span of a catalyst charge. Moreover, it enables to reduce pollution in the installations using said method.

A process for preparing a hydrocyanation catalyst comprising contacting a bidentate phosphorous-containing ligand with nickel chloride in the presence of a nitrile solvent and a reducing metal which is more electropositive than nickel the nickel chloride being introduced as an aqueous solution and the water being removed concurrently with the reduction reaction by azeotropic distillation.

The invention provides a preparation method of isophorone nitrile. According to the method, addition reaction between isophorone and hydrocyanic acid is performed to produce isophorone nitrile in the presence of a basic catalyst, wherein the basic catalyst is a basic anion exchange resin. The crude product prepared by the preparation method can be directly purified, the steps of catalyst treatment for separating the product from the catalyst thereby simplifying the preparation process, reducing equipment investment, shortening material process flow and lowering material consumption, and achieving more environmentally-friendly effect.