The present work focuses on the extraction of Cu, suitable for production, directly from a leach solution of a chalcopyrite concentrate as an alternative to the conventional smelting and refining method. Firstly, the main aspects of the kinetics of chalcopyrite leaching in a sulphuric-acid solution and transformation reactions of chalcopyrite at high temperatures were briefly reviewed. Secondly, atmospheric-acid leaching experiments were performed as a function of the acid content and temperature under agitation. Direct leaching experiments resulted in very low and scattered Cu recoveries, hence revealing a sulphide passivation layer on the chalcopyrite. In order to get rid of this layer, the sulphides in the chalcopyrite were transformed into sulphates with heat treatment at 500°C prior to the leaching process, in which a high dissolution of species was obtained. Finally, the leaching of the pre-heated concentrate resulted in a 99.82 % Cu extraction. Consequently, optimized process parameters were proposed by comparing the Cu extraction and the increased purity of the pregnant solution without Fe impurities. Keywords: chalcopyrite concentrate, leaching, heat treatment, passivation layer, copper extraction, selectivity Namen tega dela je ekstrakcija bakra (Cu), ki bi bila primerna za neposredno proizvodnjo iz lu`ine koncentrata halkopirita, kot alternative obi~ajni metodi s taljenjem in rafinacijo. Najprej je bil opravljen pregled glavnih vidikov kinetike izlu`evanja halkopirita v raztopini solne kisline in reakcij pretvorbe halkopirita pri visokih temperaturah. Nato so bili izvedeni preizkusi izlu`evanja na zraku v kislini, v odvisnosti od vsebnosti kisline in temperature z me{anjem. Neposredni preizkusi izlu`evanja so pokazali zelo nizko in raztreseno pridobitev bakra, ker se je halkopirit prekril s sulfidnim pasivacijskim slojem. Da bi se tega sloja znebili, so bili sulfidi v halkopiritu pretvorjeni v sulfate, s toplotno obdelavo pri 500°C pred postopkom izlu`evanja, pri katerem je bilo dose`eno dobro raztapljanje vzorca. Kon~no je bilo dose`eno 99,82 % izlu`evanje bakra (Cu) iz predogretega koncentrata. Posledi~no so bili predlagani optimalni parametri procesa s primerjavo ekstrakcije bakra (Cu) in pove~ane~istosti nosilne raztopine brez ne~isto~`eleza (Fe).

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