CO_2 sequestration utilizing basic-oxygen furnace slag：Controlling factors,reaction mechanisms and V–Cr concerns

2 orders） by slag carbonation.In contrast,slag carbonation did not promote chromium release until the reaction duration exceeded 24 hr.However,the water chromium content was generally at least an order lower than the vanadium concentration,which decreased when the reaction duration exceeded 24 hr.Therefore,long reaction durations of 48-96 hr are proposed to reduce environmental impacts while keeping high carbonation degrees.Mineral textures and water compositions indicated that Mg-wustite,in addition to CaO-containing minerals,can also be carbonated.Consequently,the conventional expression that only considered carbonation of the CaO-containing minerals undervalued the CO2 sequestration capability of the BOF-slag by20%.Therefore,the BOF-slag is a better CO2 storage medium than that previously recognized.