Direct Contact Membrane Distillation for Separation of Hcl From A Mixture of Acids

Abstract

HCl is separated from HCl –H₂SO₄  solution by membrane distillation process(MD). The flat –sheet membranes made from polyvinylidene fluoride (PVDF) and polypropylene (pp.). Plate and frame these types of membrane where used in the process. The feed is a mixture of HCl and H₂SO₄ acids compositions depended on metals treated object.HCl concentration increased in the permeate during the process but sulfuric acid increased gradually in the feed .During the concentration of solution acids concentrations in the feed at the beginning were 50 g/dm³ of sulfuric acid and 50 g/dm³ of hydrochloric acid at 333K feed temperature the permeate flux was 71 dm³/m².d. At a higher  concentration of HCl  in the feed  111g /dm³  and 61 g/ dm³ of sulfuric acid  at the feed temperature 333K  volume permeate flux was 57 dm³/ m².d . At a higher concentration of  sulfuric acid  in the feed 161 g/dm³ and 60 g/dm³ of HCl decrease the permeate flux from 71 to 35 dm³/m².d at 333K . The permeate flux increase from 35 at 333K to 85 at 343 K increase the temperature caused an increase in permeate flux. Increases in sulfuric acid concentration from 50 to 161 g/dm3 decrease the volume permeate flux from 71 to 35 dm3 /m².d, HCl concentration was achieved a higher value 9.1 g/dm³ during the process at the feed concentration 161g/dm³ of sulfuric acid and 60g/dm³ of hydrochloric acid at feed temperature 343K.