Process for dehydrating acid halide azeotropes with lithium salts

Claim 2

The process of claim 2 wherein said hydrogen halide component in gaseous form is cooled below about 27* C., thereby separating at least the major portion of any water vapor entrained therewith as aqueous hydrogen halide acid.

Claim 3

The process of claim 3 wherein said aqueous hydrogen halide acid is recycled.

Claim 4

The process of claim 2 wherein the hydrogen halide acid is hydrochloric acid, the lithium salt is lithium chloride, and the lithium chloride/hydrochloric acid aqueous mixture contains at least 30 wt percent lithium chloride.

Claim 5

The process of claim 2 wherein the hydrogen halide acid is hydrobromic acid, and the lithium salt is lithium bromide.

Claim 6

The process of claim 2 wherein the hydrogen halide acid is hydriodic acid, and the lithium salt is lithium iodide.

Claim 7

The process of claim 5 wherein the lithium chloride/hydrochloric acid mixture is maintained between 50* and 100* C.

Claim 8

The process of claim 5 wherein the lithium chloride/hydrochloric acid aqueous mixture contains 40-55 wt. percent lithium chloride.

Claim 9

The process of claim 5 wherein the lithium chloride/hydrochloric acid mixture is maintained between 110* and 135* C.

Claim 10

The process of claim 5 wherein the lithium chloride-water mixture remaining after the heating step is further heated to a temperature between about 100* and 170* C., thereby removing essentially all hydrogen chloride remaining therein.

Claim 11

The process of claim 11 wherein the lithium chloride-water mixture is rendered substantially anhydrous.

Claim 12

The process of claim 12 wherein the essentially HCl-free lithium chloride-water mixture is heated at a subatmospheric pressure such that the boiling point of said mixture ranges from about 40* C. to 80* C.

Claim 13

A process for dehydrating aqueous solutions of hydrogen halide acids seleCted from the group consisting of hydrochloric acid, hydrobromic acid, and hydriodic acid which comprises: a. maintaining a mixture of an aqueous solution of hydrogen halide acid and a lithium salt of said corresponding hydrogen halide at an elevated temperature to generate predominately gaseous hydrogen halide and minor amounts of water vapor, b. cooling said gaseous hydrogen halide and water vapor to condense the water vapor, c. returning the condensate to said mixture of aqueous solution of hydrogen halide and lithium salt, d. releasing said gaseous hydrogen halide, e. withdrawing the mixture of aqueous solution containing minor amounts of hydrogen halide and lithium halide and stripping therefrom substantially all the hydrogen halide leaving as bottoms, an aqueous solution of lithium halide, f. returning the evolved hydrogen halide to the mixture of aqueous solution of hydrogen halide and lithium halide, g. removing water from said bottoms and recycling the residual lithium halide to the mixture of aqueous solution of hydrogen halide and lithium halide; and h. introducing aqueous solution of hydrogen halide feed into the mixture of aqueous solution of hydrogen halide and lithium halide.