| 摘要 |
PURPOSE:To recover chromic acid and mineral acid, by adding alkali to the ex- haust liquid containg trivalent chromium salt and mineral acid salts of the other meatls and also, (not) containing mineral acids and making the residual liquid at a specific pH value after separating another metals hydroxide and then, adsorbing alkaline component by anion exchange resin etc. CONSTITUTION:Alkali is added to the exhaust liquid discharged from the formation treatment of Al, containing trivalent chromium salt and mineral acid salts of the other metals (AlPO4 etc.) and also, (not) containing mineral acids and then, hydroxides, such as Al(OH)3 etc., are separated. Next, pH of residual liquid is made more than ten and alkaline component is removed by adsorption by treating with anion exchange resin or metal adsorbent after forming hexavalent chromic acid alkali and then, chromic acid and mineral acids are recovered. |
