28 UDC 622.712.2 Обогащение полезных ископаемых Fathi Habashi, Professor emeritus, Fathi.Habashi@arul.ulaval.ca Department of Mining, Metallurgical, and Materials Engineering Laval University (Quebec City, Canada) Причиной повышения популярности соляной кислоты стала разработка технологии переработки растворов хлористого железа (2), с регенерацией соляной кислоты и получением товарных оксидов железа. <...> При переработке сложных золотосодержащих руд соляной кислотой под давлением позволяет не использовать для извлечения золота раствора цианида, так как извлечение золота из его хлоридов может быть осуществлено стандартными технологиями. <...> Түйінді сөздер: оксигидролиз, болатты улау, ильменит, синтетикалық рутил, қиын өңделетін алтынқұрамды кендер, каолинит, анортозит. <...> Sulfuric acid is the cheapest acid and is used as a leaching agent in many hydrometallurgical processes. <...> However, hydrochloric acid although more expensive since it is prepared by reaction of sulfuric with sodium chloride has replaced sulfuric acid in many reactions involving iron oxide. <...> It replaced sulfuric acid for the first time in 1960s in pickling of steel because of pollution problems [1]. <...> Ferrous chloride produced in pickling can be economically decomposed to ferric oxide and HCl according to: 2FeCl2 which also shows that the acid can be regenerated but ferrous sulfate cannot be economically decomposed to recover sulfuric acid for recycle. <...> Since then, hydrochloric acid has been used in many leaching processes. <...> Hydrochloric acid is a corrosive acid and is usually handled in rubber-lined equipment. <...> Regeneration of hydrochloric acid Regeneration of HCl is conducted in fluidized bed or in spray roaster. <...> Fluidized bed oxyhydrolysis In a fluidized bed, ferrous chloride solution is introduced onto a bed of hot + 2H2 O + ½O2 → Fe2 O3 + 4HCl, ferric oxide where heating is provided by the hot fluidizing combustion gases (pic. 1). <...> The solution is fed on top of the bed of oxides. <...> Spray roaster oxyhydrolysis In spray roaster, the ferrous chloride solution is sprayed into an empty cylindrical vessel, while the required energy is supplied by the up <...>