Process for converting heat stable amine salts to heat regenerable amine salts
AssigneeUnion Carbide Chemicals & Plastics Technology Corporation
InventorsVeronique Roy, Leo E. Hakka, Jean I. Sarlis
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Abstract
Processes are disclosed for converting heat stable amine salts to heat regenerable amine salts using a modified electrodialysis zone. The processes of the present invention can be used to reduce the level of heat stable salts in a lean solvent stream in an acid gas removal process and can be integrated with the acid gas removal process to utilize process streams as a source of ions.
Claims18
A process for converting heat stable amine salts to heat regenerable amine salts which comprises:
- (a) passing a feedstream comprising an amine in salt form having heat stable anions associated therewith to an electrodialysis zone having a cathode compartment, an anode compartment and at least one repeat unit comprising a reflux compartment disposed between the cathode compartment and the anode compartment, a product compartment disposed between the reflux compartment and the anode compartment, a feed compartment disposed between the product compartment and the anode compartment, and an acid compartment disposed between the feed compartment and the anode compartment, said feed stream being passed to the feed compartment;
- (b) passing a reflux stream comprising a salt or acid of a heat regenerable anion to the reflux compartment;
- (c) passing a direct current potential transversely across each compartment, said current being effective to cause:
- (1) amine cations to dissociated from the heat stable amine salts in the feed compartment and pass into the product compartment;
- (2) heat regenerable anions to dissociate from the salt or acid in the reflux compartment and pass into the product compartment;
- and (3) heat stable anions to dissociate from the heat stable amine salts in the feed compartment and pass into the acid compartment;
- and
- (d) discharging from the product compartment a product stream comprising an amine in salt form having regenerable anions associated therewith.
A process for converting heat stable amine salts to heat regenerable amine salts which comprises:
- (a) passing a feedstream comprising an amine in salt form having sulfate anions associated therewith to an electrodialysis zone having a cathode compartment, an anode compartment and at least one repeat unit comprising a reflux compartment disposed between the cathode compartment and the anode compartment, a product compartment disposed between the reflux compartment and the anode compartment, a feed compartment disposed between the product compartment and the anode compartment, and an acid compartment disposed between the feed compartment and the anode compartment, said regenerated solvent stream being passed to the feed compartment;
- (b) passing a reflux stream comprising a salt or acid of a sulfite anion to the reflux compartment;
- (c) passing a direct current potential transversely across each compartment, said current being effective to cause:
- (1) amine cations to dissociate from the heat stable amine salts in the feed compartment and pass into the product compartment;
- (2) sulfite anions to dissociate from the salt or acid in the reflux compartment and pass into the product compartment;
- and (3) sulfate anions to dissociate from the heat stable amine salts in the feed compartment and pass into the acid compartment;
- and
- (d) discharging from the product compartment a product stream comprising an amine in salt form having sulfite anions associated therewith.
Dependencies are inferred from the claim text.