Carbonylation process using a flash step with washing

Claim 2

A process for the production of a carboxylic acid, the process comprising the steps of: a) reacting (i) an alcohol and/or a reactive derivative of an alcohol and (ii) carbon monoxide in the presence of solid catalyst particles in a reaction zone to produce a carboxylic acid, and forming in the reaction zone a reaction effluent comprising (i) the carboxylic acid, (ii) carbon monoxide, and (iii) at least one of the solid catalyst particles, attrited solid catalyst particles, and heavy by-products; b) flashing at least a portion of the reaction effluent in a flash zone, and recovering from the flash zone an overhead fraction comprising the carboxylic acid; c) forming from the overhead fraction a vapor phase comprising carbon monoxide and an at least partial liquid phase comprising the carboxylic acid; d) separating the vapor phase and the at least partial liquid phase in an overhead receiver; e) recycling the at least partial liquid phase to the flash zone; and f) recovering a product comprising the carboxylic acid from the at least partial liquid phase.

Claim 3

The process of claim 1 further characterized in that the flash zone operates at a temperature of less than about 220° C.

Claim 4

The process of claim 1 wherein at least 50% by weight of the at least partial liquid phase is liquid.

Claim 5

The process of claim 1 further characterized in that the flashing of the reaction effluent in Step (b) comprises depositing at least one of the solid catalyst particles, the attrited solid catalyst particles, and the heavy by-products on a surface within the flash zone, and the recycling of the at least partial liquid phase in Step (e) comprises contacting at least a portion of the surface containing deposits of at least one of the solid catalyst particles, the attrited solid catalyst particles, and the heavy by-products with liquid and removing at least a portion of the deposits from the surface.

Claim 6

The process of claim 4 further characterized in that the flash zone comprises a vessel having an inner wall, and at least part of the surface comprises at least part of the inner wall.

Claim 7

The process of claim 4 further characterized in that the flash zone comprises a packed section containing packing, and at least part of the surface comprises at least part of the packing.

Claim 8

The process of claim 1 further characterized in that a bottom stream comprising at least one of the solid catalyst particles and the attrited solid catalyst particles is withdrawn from the flash zone, and at least a portion of the bottom stream is recycled to the reaction zone.

Claim 9

The process of claim 1 wherein the overhead fraction comprises at least one of the group consisting of carbon monoxide, an ester corresponding to the esterification of the alcohol and the carboxylic acid, and water.

Claim 10

The process of claim 1 wherein the solid catalyst particles comprise a polyvinylpyridine resin.

Claim 11

The process of claim 1 wherein the solid catalyst particles comprise a polyvinylpyrrolidone resin.

Claim 12

The process of claim 1 wherein the alcohol comprises methanol, and the carboxylic acid comprises acetic acid.

Claim 13

A process for the production of a carboxylic acid, the process comprising the steps of: a) reacting (i) an alcohol and/or a reactive derivative of an alcohol and (ii) carbon monoxide in the presence of solid catalyst particles in a reaction zone to produce a carboxylic acid, and forming in the reaction zone a reaction effluent comprising carbon monoxide, water, an ester corresponding to the esterification of the alcohol and the carboxylic acid, the carboxylic acid, and at least one of the group consisting of the solid catalyst particles, the attrited solid catalyst particles, and the heavy by-products; b) flashing the reaction effluent in a vertically-oriented flash zone, wherein the flash zone has a rectification section in an upper portion of the flash zone and a packed section in a lower portion of the flash zone and wherein the packed section contains packing, withdrawing from the flash zone at a point above the top of the rectification section a vapor fraction comprising carbon monoxide, water, and the ester, forming in the flash zone at a point below the top of the rectification section and above the top of the packed section a liquid fraction comprising the carboxylic acid, and withdrawing a bottom stream comprising the carboxylic acid and at least one of the group consisting of the solid catalyst particles, the attrited solid catalyst particles, and the heavy by-products from a point below the packed section; c) recycling the liquid fraction to a point below the point of formation of the liquid fraction and above the top of the packed section; and d) recovering a crude product comprising the carboxylic acid from the liquid fraction.

Claim 14

A process for the production of a carboxylic acid, the process comprising the steps of: a) reacting (i) an alcohol and/or a reactive derivative of an alcohol and (ii) carbon monoxide in the presence of solid catalyst particles in a reaction zone to produce a carboxylic acid, and forming in the reaction zone a reaction effluent comprising carbon monoxide, water, an ester corresponding to the esterification of the alcohol and the carboxylic acid, the carboxylic acid, and at least one of the group consisting of the solid catalyst particles, the attrited solid catalyst particles, and the heavy by-products; b) flashing the reaction effluent in a vertically-oriented flash zone, wherein the flash zone has a rectification section in an upper portion of the flash zone and a packed section in a lower portion of the flash zone and wherein the packed section contains packing, withdrawing from the flash zone at a point above the top of the rectification section a vapor fraction comprising carbon monoxide, water, and the ester, forming in the flash zone at a point below the top of the rectification section and above the top of the packed section a liquid fraction comprising the carboxylic acid, and withdrawing a bottom stream comprising the carboxylic acid and at least one of the group consisting of the solid catalyst particles, the attrited solid catalyst particles, and the heavy by-products from a point below the packed section; c) recycling the liquid fraction to a point below the point of formation of the liquid fraction and above the top of the packed section; and d) recovering a crude product comprising the carboxylic acid from the liquid fraction.

Claim 15

The process of claim 12 further characterized in that the flashing of the reaction effluent in Step (b) comprises depositing at least one of the solid catalyst particles, the attrited solid catalyst particles, and the heavy by-products on the packing within the packed section, and the recycling of the crude fraction in Step (c) comprises contacting at least a portion of the packing containing deposits of at least one of the solid catalyst particles, the attrited solid catalyst particles, and the heavy by-products with liquid and removing at least a portion of the deposits from the packing.

Claim 16

The process of claim 12 wherein the carboxylic acid comprises acetic acid and the ester comprises methyl acetate.

Claim 17

The process of claim 1 wherein the at least partial liquid phase comprises water.

Claim 18

The process of claim 12 wherein the solid catalyst particles comprise a polyvinylpyridine resin.

Claim 19

The process of claim 12 wherein the solid catalyst particles comprise a polyvinylpyrrolidone resin.

Claim 20

The process of claim 12 wherein the liquid fraction comprises water.

Claim 21

The process of claim 12 further characterized in that a vapor phase comprising carbon monoxide, a water-poor phase comprising the ester, and a water-rich phase comprising the ester are formed from the vapor fraction; the vapor phase, the water-poor phase, and the water-rich phase are separated in an overhead receiver; and the water-rich phase is recycled to the flash zone.

Claim 22

The process of claim 19 further characterized in that the water-rich phase is recycled to a point above the top of the rectification section.

Claim 23

The process of claim 19 further characterized in that the water-poor phase comprises methyl iodide.