Abstract: A process for preparing at least one partial oxidation and/or ammoxidation product of a hydrocarbon by partially dehydrogenating at least one saturated hydrocarbon H under heterogeneous catalysis and using the resulting product gas mixture A, which comprises the partially dehydrogenated hydrocarbon H, as such or in modified form for heterogeneously catalyzed partial oxidation and/or ammoxidation of the partially dehydrogenated hydrocarbon present in the product gas mixture A, said process including at least one mechanical separating operation inserted between the product gas mixture A and the heterogeneously catalyzed partial oxidation and/or ammoxidation.

Abstract: The process for manufacturing unsaturated mononitriles, such as acrylonitrile and methacrylonitrile, has been modified to add a partially condensed quench effluent stripper column to remove high boiling organic compounds from the reactor effluent prior to introduction into the extractive distillation recovery column. The high boiling organic compounds are preferably removed after the ammonia in the reactor effluent has been neutralized and the neutralization products have been removed. The targeted high boiling organic compounds are associated with fouling in the recovery section of the plant.

Abstract: A catalyst for the selective oxidation and amoxidation of alkanes and/or alkenes, particularly in processes for obtaining acrylic acid, acrylonitrile and derivatives of these, including a least one oxide of Mo, Te, V, Cu and at least another A component selected from among Nb, Ta, Sn, Se, W, Ti, Fe, Co, Ni, Cr, Ga, Sb, Bi, a rare, alkaline or alkali-earth earth, in such a way that the catalyst presents, in a calcined form, an X-ray diffractogram with five intensive diffraction lines, typically the most intense corresponding to diffraction angles of 2? at 22.1±0.4, 27.1±0.4; 28.1±0.4, 36.0±0.4 and 45.1±0.4. In the preferred embodiment, the catalyst has the following empiric formula: MoTehViCujAkOx in which h, i, j, k are values comprised between 0.001 and 4.0 and x depends on the oxidation status or valency of the Mo, Te, V, Cu and A elements.

Abstract: In a process for preparing at least one partial oxidation and/or ammoxidation product of propylene, the propylene is obtained from crude propane by dehydrogenating and subjected in the presence of unconverted propane as a constituent of a gas mixture 2 which comprises a total C4-hydrocarbon content of ?3% by volume to a heterogeneously catalyzed gas phase partial oxidation and/or partial gas phase ammoxidation.

Abstract: The invention relates to a process for preparing unsaturated nitrites from the corresponding alkanes which comprises the steps: a) feeding an alkane into a dehydrogenation zone and catalytically dehydrogenating the alkane to the corresponding alkene to obtain a product gas stream A which comprises the alkene, unconverted alkane and possibly one or more further gas components selected from the group consisting of steam, hydrogen, carbon oxides, hydrocarbons having a lower boiling point than the alkane or the alkene (low-boilers), nitrogen and noble gases, b) at least partially removing further gas components from the product gas stream A to give a feed gas stream B which comprises the alkane and the alkene, c) feeding the feed gas stream B, ammonia, an oxygen-containing gas and, if desired, steam into an oxidation zone and catalytically ammoxidizing the alkene to the corresponding unsaturated nitrile to give a product gas stream C which comprises the unsaturated nitrile, ammoxidation by-products, unconverte

Abstract: Process for recovery of highly pure acrylonitrile by quickly vaporizing under vacuum the contaminated acrylonitrile as well as fresh acrylonitrile followed by contacting with hydrophilic agents in an extractive distillation column using plural number of packed sections.

Abstract: Economical processes are disclosed for recovery and refining of valuable nitrogen-containing organic compounds formed by catalytic oxidation of least one feed compound selected from the group consisting of propane, propylene, isobutane and isobutylene in the presence of ammonia to produce a gaseous. Processes of the invention include quenching the gaseous reactor effluent with an aqueous quench liquid; forming an aqueous solution comprising the corresponding unsaturated mononitrile, hydrogen cyanide and other organic co-products; and using an integrated sequence of distillations and phase separations to recover for recycle of a useful aqueous liquid, and obtain the desired nitrogen-containing products. According to the invention aqueous solutions are fractionated in an integrated system of multi-stage columns while an effective polymerization inhibiting amount of at least one member of a preselected class of p-phenylenediamine compounds is maintained therein.

Abstract: An overhead stream from the quench system in a process for purifying acrylonitrile is condensed and recycled directly to the quench system as part of the quench liquid. The stream can be condensed in a column or in a partial condenser.

Abstract: Process for recovery of highly pure acrylonitrile by quickly vaporizing under vacuum the contaminated acrylonitrile as well as fresh acrylonitrile followed by contacting with hydrophilic agents in an extractive distillation column using plural number of packed sections.

Abstract: Process for isolating one or more organic substances from a gas mixture in which these organic substances are present, in which the gas mixture is subjected to a quenching in a column, characterized in that quenching is carried out in the upper part of the column and the quenching liquid is subjected to stripping in the lower part of the column.

Abstract: A process for purifying a nitrile such as acrylonitrile is disclosed. The process comprises (1) contacting a product mixture, which comprises acrylonitrile and hydrogen cyanide, with an acid or a precursor of the acid to produce an acid-treated product; and (2) recovering the nitrile from the acid-treated product. The product mixture can be produced by contacting ammonia with a hydrocarbon such as an olefin under a condition effective to produce a nitrile and hydrogen cyanide.

Abstract: The process of manufacturing an unsaturated mononitrile selected from the group consisting of acrylonitrile and methacrylonitrile comprising transporting a reactor effluent containing the unsaturated mononitrile to a first column where the reactor effluent is cooled with at least one aqueous stream, transporting the cooled effluent containing the unsaturated mononitrile into a second column where the cooled effluent is contacted with at least one second aqueous stream to absorb the unsaturated mononitrile into at least one second aqueous stream, transporting the second aqueous stream containing the unsaturated mononitrile from the second column to a first distillation column for separation of the crude unsaturated mononitrile from the second aqueous stream, and transporting the separated crude unsaturated mononitrile to a second distillation column to remove at least some impurities from the crude mononitrile, and transporting the partially purified crude unsaturated mononitrile to a third distillation column

Abstract: A process for purifying a nitrile such as acrylonitrile is disclosed. The process comprises (1) contacting a product mixture, which comprises acrylonitrile and hydrogen cyanide, with glycolic acid or a glycolic acid-generating compound to produce a glycolic acid-treated product; and (2) recovering the nitrile from the glycolic acid-treated product. The product mixture can be produced by contacting ammonia with an olefin under a condition effective to produce a nitrile and hydrogen cyanide.

Abstract: A method for improving purification efficiency when distilling off aldehyde contaminants during chemical manufacturing processes by adding a substituted aromatic amine having electron donating group substituents prior to the distillation column. The method is particularly useful for removal of aldehydes such as acrolein, generated as a by-product of acrylonitrile manufacture. Preferred aromatic amines are 2-amino aniline, 3,4-dimethyl aniline and 4-ethyl aniline.

Abstract: The process of the present invention comprises transporting a reactor effluent containing acrylonitrile/methacrylonitrile to a first column (quench) where the reactor effluent is cooled with a first aqueous stream, transporting the cooled effluent into an indirect contact cooler to condensed at least some of the cooled effluent to form a condensate comprising water and acrylonitrile/methacrylonitrile, transporting the remaining cooled gaseous effluent containing acrylonitrile/methacrylonitrile into a second column (absorber) where the cooled effluent is contacted with a second aqueous stream to absorb substantially all of the remaining acrylonitrile/methacrylonitrile into the second aqueous stream, transporting the second aqueous stream containing the acrylonitrile/methacrylonitrile to a first distillation column (recovery column) for separation of the crude acrylonitrile/methacrylonitrile from the second aqueous stream, and transporting the separated crude acrylonitrile/methacrylonitrile to a second distilla

Abstract: The present invention provides substituted phenols which are effective to inhibit polymer formation during the manufacture of acrylonitrile. Preferred substituted phenols are (a) hindered phenols, nonhindered phenols, and partially hindered phenols, or (b) combinations of hindered phenols with nonhindered or partially hindered phenols. A most preferred substituted phenol is p-nitrosophenol. In a preferred embodiment, the substituted phenols (with the exception of p-nitrosophenol) are combined with hydrogen transfer agents.

Abstract: This invention relates to a method for preparing acrylonitrile by ammoxydation using a multi-story quenching tower. The method comprises the steps of supplying the reacted gas into the first quenching chamber of the multi-story quenching tower, said first quenching chamber has a water supply pipe equipped with spray nozzles at a two-dimensional density of more than 2 nozzles/m.sup.2 for the sectional area of the multi-story quenching tower and contacting the reacted gas with 5 T or more of water per 1 T of the reacted gas fed from the nozzles.

Abstract: A process for the recovery of acrylonitrile or methacrylonitrile obtained from the reactor effluent of an ammoxidation reaction of propylene or isobutylene comprising passing the reactor effluent through an absorber column and recovery column and stripper column wherein the improvement comprises increasing the recovery column top pressure by mechanical means by about 0.1 to 5 psi to improve the hydraulic capacity of the recovery and stripper columns.

Abstract: A process for the recovery of acrylonitrile or methacrylonitrile obtained from the reactor effluent of an ammoxidation reaction of propylene or isobutylene comprising passing the reactor effluent through an absorber column, a first decanter, recovery column, a second decanter and stripper column wherein the improvement comprises maintaining inside temperature of the first and second decanter at between about 32.degree. F. to 75.degree. F.

Abstract: Methacrylonitrile higher in purity than that obtained by the conventional process is efficiently produced by the present improved process for producing purified methacrylonitrile in which the reaction mixture formed by the ammoxidation of isobutylene or tert-butyl alcohol is distilled using water as solvent to obtain a crude methacrylonitrile solution which contains methacrylonitrile as major constituent, methacrolein, hydrogen cyanide, and isobutyronitrile, and the crude methacrylonitrile solution is then purified in a product column, wherein the improvement comprises first removing isobutyronitrile from said crude solution, then feeding the remaining solution to the product column, withdrawing from the top a vapor containing methacrolein, condensing the vapor, returning a greater part of the condensate to the product column while removing the remainder from the distillation system, and withdrawing purified methacrylonitrile from the middle or lower section, preferably from a point lower than the feeding sta