Acid Regeneration Process
Acid Regeneration Process The commercially most relevant field of application for HCl regeneration processes is the recovery of HCl from waste pickle liquors from carbon steel pickling lines. Other applications include the production of metal oxides such as, but not limited, to Al2O3 and MgO as well as rare earth oxides by pyrohydrolysis of aqueous metal chloride or rare earth chloride solutions. A number of different process routes are available. The most widely used is based on pyrohydrolysis and adiabatic absorption of hydrogen chloride in water, a process invented in the 1960s. However tightening environmental standards and stringent air permit policies render it increasingly difficult to establish new pyrohydrolysis based acid regeneration plants.