PROCESS FOR PRODUCING UNSATURATED NITRILE

• US 20190225576A1
• Filed: 06/08/2018
• Published: 07/25/2019
• Est. Priority Date: 06/09/2017
• Status: Active Grant

• Current Assignee: Asahi Kasei Kabushiki Kaisha (Asahi Kasei Corporation)
• Original Assignee: Asahi Kasei Kabushiki Kaisha (Asahi Kasei Corporation)
• Inventors: TAMURA, Sho, NAGATA, Dai
• Granted Patent: US 10,640,458 B2
• Time in Patent Office: Days
• CPC Class Codes: B01J 21/08 Silica
• CPC Class Codes: B01J 2208/00548 Flow
• CPC Class Codes: B01J 23/002 Mixed oxides other than spinels, e.g. perovskite
• CPC Class Codes: B01J 23/28 Molybdenum
• CPC Class Codes: B01J 23/30 Tungsten
• CPC Class Codes: B01J 23/8876 Arsenic, antimony or bismuth
• CPC Class Codes: B01J 2523/00 Constitutive chemical elements of heterogeneous catalysts
• CPC Class Codes: B01J 2523/14 Rubidium
• CPC Class Codes: B01J 2523/22 Magnesium
• CPC Class Codes: B01J 2523/3712 Cerium
• CPC Class Codes: B01J 2523/41 Silicon
• CPC Class Codes: B01J 2523/53 Antimony
• CPC Class Codes: B01J 2523/54 Bismuth
• CPC Class Codes: B01J 2523/55 Vanadium
• CPC Class Codes: B01J 2523/56 Niobium
• CPC Class Codes: B01J 2523/68 Molybdenum
• CPC Class Codes: B01J 2523/69 Tungsten
• CPC Class Codes: B01J 2523/842 Iron
• CPC Class Codes: B01J 2523/847 Nickel
• CPC Class Codes: B01J 35/31 Density
• CPC Class Codes: B01J 35/40 : characterised by dimensions, e.g. grain size in a colloidal state B01J35/23; crystallite size B01J35/77
• CPC Class Codes: B01J 35/50 : characterised by their shape or configuration
• CPC Class Codes: B01J 37/088 : Decomposition of a metal salt
• CPC Class Codes: B01J 8/0055 : using cyclones
• CPC Class Codes: B01J 8/1818 : Feeding of the fluidising gas B01J8/44 takes precedence
• CPC Class Codes: B01J 8/1827 : the fluidising gas being a reactant
• CPC Class Codes: B01J 8/24 : according to "fluidised-bed" technique B01J8/20 takes precedence
• CPC Class Codes: C07C 253/24 : by ammoxidation of hydrocarbons or substituted hydrocarbons
• CPC Class Codes: C07C 253/26 : containing carbon-to-carbon multiple bonds, e.g. unsaturated aldehydes
• CPC Class Codes: C07C 255/08 : Acrylonitrile; Methacrylonitrile
• CPC Class Codes: Y02P 20/52 : using catalysts, e.g. selective catalysts

Abstract

A process for producing unsaturated nitrile, using a fluidized bed reactor having an internal space having a catalyst capable of being fluidized therein, a feed opening to feed a starting material gas comprising hydrocarbon to the internal space, and a discharge port to discharge a reaction product gas from the internal space, the process comprising a reaction step of subjecting the hydrocarbon to a vapor phase catalytic ammoxidation reaction in the presence of the catalyst in the internal space to produce the corresponding unsaturated nitrile, wherein when in the internal space, a space where an existing amount of the catalyst per unit volume is 150 kg/m³ or more is defined as a dense zone and a space where an existing amount of the catalyst per unit volume is less than 150 kg/m³ is defined as a sparse zone in the reaction step, a gas residence time in the sparse zone is 5 to 50 sec.

Claims

1. A process for producing unsaturated nitrile, using a fluidized bed reactor having an internal space comprising a catalyst capable of being fluidized therein;

a feed opening to feed a starting material gas comprising hydrocarbon to the internal space; and

a discharge port to discharge a reaction product gas from the internal space, the process comprising a reaction step of subjecting the hydrocarbon to a vapor phase catalytic ammoxidation reaction in the presence of the catalyst in the internal space to produce the corresponding unsaturated nitrile, wherein

when in the internal space, a space where an existing amount of the catalyst per unit volume is 150 kg/m³ or more is defined as a dense zone and a space where an existing amount of the catalyst per unit volume is less than 150 kg/m³ is defined as a sparse zone in the reaction step, a gas residence time in the sparse zone is 5 to 50 sec.

2. The process for producing the unsaturated nitrile according to claim 1, wherein a superficial gas velocity in the sparse zone is less than 1 m/s in the reaction step.

3. The process for producing the unsaturated nitrile according to claim 1, wherein an oxygen concentration in the reaction product gas discharged from the discharge port is 0.1 vol % or more in the reaction step.

4. The process for producing the unsaturated nitrile according to claim 1, wherein the oxygen concentration in the reaction product gas discharged from the discharge port is 0.1 vol % or more but 5.0 vol % or less in the reaction step.

5. The process for producing the unsaturated nitrile according to claim 1, wherein

when the oxygen concentration in the reaction product gas discharged from the discharge port is less than 2.0 vol % in the reaction step, the relation of

(the gas residence time)≤

7.5×

(the oxygen concentration)+30 is satisfied, and

when the oxygen concentration in the reaction product gas discharged from the discharge port is 2.0 vol % or more in the reaction step, the relation of

(the gas residence time)≤

−

3×

(the oxygen concentration)+50 is satisfied.

6. The process for producing the unsaturated nitrile according to claim 1, wherein the hydrocarbon is propane and/or propylene.