Production of cyclic imides suitable for oxidation catalysis

Patent metadata

Field	Value
Publication number	US-11161812-B2
Application number	US-201716096091-A
Country	US
Kind code	B2
Filing date	Apr 18, 2017
Priority date	May 26, 2016
Publication date	Nov 2, 2021
Grant date	Nov 2, 2021

Abstract

Disclosed are novel processes for the production of cyclic imide compounds such as N-hydroxyphthalimide (NHPI). The processes may be particularly well-suited for commercial-scale production of cyclic imides such as NHPI. Such cyclic imide compounds are suitable for use as oxidation catalysts, and specifically may be used to oxidize cyclohexylbenzene to cyclohexyl-1-phenyl-1-hydroperoxide. Such an oxidation may be particularly useful in a process for the production of phenol and/or cyclohexanone from benzene via a process comprising hydroalkylation of benzene to cyclohexylbenzene, oxidation of the cyclohexylbenzene to cyclohexyl-1-phenyl-1-hydroperoxide, and cleavage of the cyclohexyl-1-phenyl-1-hydroperoxide to phenol and cyclohexanone. The cyclic imide production process may advantageously include water washing and reactant recovery steps to maximize purity and yield.

First claim

The invention claimed is:

1. A process comprising:
(a) contacting a hydroxylamine solution with a cyclic carboxylic acid anhydride so as to form a reaction medium having initial temperature T i of less than 65° C.;
(b) raising the reaction medium temperature to a transition temperature T t within the range from 65° C. to less than 75° C., thereby forming a first slurry comprising solid intermediate hydroxamic acid within the reaction medium;
(c) further heating the reaction medium to a final temperature T f within the range from 75° C. to 200° C., thereby converting at least a portion of the solid intermediate hydroxamic acid to solid cyclic imide, such that the reaction medium comprises a second slurry comprising the solid cyclic imide;
wherein the cyclic carboxylic acid anhydride has the general formula (II)

and further wherein the cyclic imide has the general formula (I)

where, in each formula (I) and (II), X is an oxygen atom or a hydroxyl group, and further wherein each of R 7 , R 8 , R 9 , and R 10 is independently selected from: (1) H; (2) C 1 to C 20 linear, cyclic, or aromatic hydrocarbon groups; (3) SO 3 H; (4) NH 2 ; (5) OH; (6) a halogen; and (7) NO 2 ;
wherein the process comprises continuously feeding the hydroxylamine solution and carboxylic acid anhydride to a continuous flow reactor via one or more feed inlets, so as to establish the reaction medium flowing continuously in a downstream direction within the continuous flow reactor; at a second location along the continuous flow reactor that is downstream of the one or more feed inlets, feeding steam or water into the reaction medium; at a third location along the continuous flow reactor that is downstream of the second location, feeding additional steam or additional water into the reaction medium; agitating the reaction medium within the continuous flow reactor between the second and third locations; and recovering a reaction product comprising solid cyclic imide from the reaction medium; and
wherein, the continuous flow reactor is in fluid communication with (i) a first steam conduit and (ii) a second steam conduit downstream of the first steam conduit,
wherein (b) raising the reaction medium temperature to the transition temperature T t comprises adding steam to the reaction medium through the first steam conduit, and
wherein (c) further heating the reaction medium to the final temperature T f comprises adding additional steam to the reaction medium through the second steam conduit.

2. The process of claim 1 , wherein each of R 7 , R 8 , R 9 , and R 10 is independently selected from one of: (i) H and (ii) linear or branched alkyl groups having 1 to 5 carbon atoms.

3. The process of claim 2 , wherein the carboxylic acid anhydride is phthalic anhydride, the intermediate hydroxamic acid is N-hydroxyphthalamic acid (NHPA), and the cyclic imide is N-hydroxyphthalimide (NHPI).

4. The process of claim 1 , wherein the temperature of the reaction medium is raised from the initial temperature T i to the transition temperature T t at a rate within the range from 0.01 to 500° C./min.

5. The process of claim 1 , further comprising monitoring the temperature of the reaction medium at a first location and, based at least in part upon the temperature at the first location, controlling one or both of (i) reaction medium flow rate in the continuous flow reactor and (ii) flow rate of the steam through the first conduit in order to raise the reaction medium temperature to the transition temperature T t .

6. The process of claim 5 , wherein the controlling results in raising the reaction medium temperature from the initial temperature T i to the transition temperature T t at a rate within the range from 0.01 to 500° C./min.

7. The process of claim 1 , further comprising monitoring the temperature of the reaction medium at a second location and, based at least in part upon the temperature at the second location, controlling one or both of (i) reaction medium flow rate in the continuous flow reactor and (ii) flow rate of the additional steam through the second steam conduit in order to raise the reaction medium temperature to the final temperature T f .

8. The process of claim 1 , wherein the hydroxylamine solution comprises (a) 30-70 wt % hydroxylamine, (b) water, and (c) less than 1 wt % of compounds other than hydroxylamine and water.

9. The process of claim 1 , wherein the hydroxylamine solution is formed by a process comprising:
(a-1) contacting a hydroxylammonium salt with an aqueous base to form at least a portion of said hydroxylamine solution.

10. The process of claim 9 , wherein the hydroxylammonium salt is hydroxylammonium sulfate.

11. The process of claim 9 , wherein the aqueous base is selected from the group consisting of sodium hydroxide and ammonia.

12. The process of claim 1 , wherein the solid cyclic imide comprises NHPI crystals having diameter within the range from 5 μm to 50 μm, and length within the range from 200 μm to 525 μm.

13. The process of claim 1 , further comprising providing at least a portion of the solid cyclic imide to an oxidation reaction.

14. The process of claim 1 , further comprising contacting at least a portion of the solid cyclic imide with cyclohexylbenzene and an oxygen-containing gas so as to obtain cyclohexyl-1-phenyl-1-hydroperoxide.

15. A process comprising:
(a) contacting a hydroxylamine solution with a cyclic carboxylic acid anhydride so as to form a reaction medium having initial temperature T i of less than 65° C.;
(b) raising the reaction medium temperature to a transition temperature T t within the range from 65° C. to less than 75° C., thereby forming a first slurry comprising solid intermediate hydroxamic acid within the reaction medium;
(c) further heating the reaction medium to a final temperature T f within the range from 75° C. to 200° C., thereby converting at least a portion of the solid intermediate hydroxamic acid to solid cyclic imide, such that the reaction medium comprises a second slurry comprising the solid cyclic imide;
wherein the cyclic carboxylic acid anhydride has the general formula (II)

and further wherein the cyclic imide has the general formula (I)

where, in each formula (I) and (II), X is an oxygen atom or a hydroxyl group, and further wherein each of R 7 , R 8 , R 9 , and R 10 is independently selected from: (1) H; (2) C 1 to C 20 linear, cyclic, or aromatic hydrocarbon groups; (3) SO 3 H; (4) NH 2 ; (5) OH; (6) a halogen; and (7) NO 2 ;
wherein the process comprises continuously feeding the hydroxylamine solution and carboxylic acid anhydride to a continuous flow reactor via one or more feed inlets, so as to establish the reaction medium flowing continuously in a downstream direction within the continuous flow reactor; at a second location along the continuous flow reactor that is downstream of the one or more feed inlets, feeding steam or water into the reaction medium; at a third location along the continuous flow reactor that is downstream of the second location, feeding additional steam or additional water into the reaction medium; agitating the reaction medium within the continuous flow r

Assignees

• Exxonmobil Chemical Patents Inc

Inventors

• Weber Jörg F W
• Jaensch Helge
• Witt Andrew R
• Becker Christopher L
• Nadler Kirk C
• Galvan Kendele S
• Batton Amy B

Classifications

• B01J2219/00029

  Batch processes · CPC title

• B01J19/0013

  Controlling the temperature of the process · CPC title

• B01J2219/00164

  controlling the flow · CPC title

• B01J19/18

  Stationary reactors having moving elements inside (B01J19/08, B01J19/26 take precedence) · CPC title

• C07D209/48 Primary

  with oxygen atoms in positions 1 and 3, e.g. phthalimide · CPC title