| abstract |
Process for working up an aqueous, salt-containing acid solution which contains at least one acid which forms at least one azeotrope with water, to obtain a salt-free acid solution and a salt solution with reduced acid content, in which the salt-containing acid solution is applied to a first column (K1), in which the saline acid solution is separated to obtain water as the top product, a higher-boiling vaporous water-acid mixture and a bottoms fraction in the form of a concentrated acidic salt solution, in which the bottoms fraction from the first column is separated to further remove acid from the concentrated saline solution (K1) to a downstream stripping column (K2) in which the bottom fraction is separated with energy input into (i) a vaporized acid fraction drawn off from the top region of the stripping column (K2) and (ii) one drawn off as a liquid from the bottom of the stripping column completely or largely acid-free concentrated salt solution. |