Regenerating HCl pickling acid in hot dip galvanizing industry
Could someone advise us how to regenerate pickling acid (HCl) in the hot dip galvanizing industry...enhancing probably some product? i.e., Can the rough mixture FeCl2, FeCl3 be used as coagulant? is it possible in drinkable water treatment? What do you think of oxidizing it into iron sulphate which is said to be strongly recommended as fertilizer...
Achraf Bouzgarrou - Tunisia 1999
Dear Mr Achraf,
Try adding about 5 % of sulfuric acid to the dead HCl bath.
It does revive the pickling activity of spent HCl baths to an extent and the bath life can be prolonged for some more time by dosing sulfuric. Careful not to add too quickly.
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