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A combined strategy of calcium-cured alkali roasting and water leaching was devised to treat secondary aluminum dross. The effects of calcium oxide dosage, sodium hydroxide dosage, roasting temperature, and time on aluminum extraction behavior and fluorine curing behavior were studied. Under optimal experimental conditions: roasting temperature of 1000 °C, Al꞉NaOH mole ratio of 1꞉0.6, F꞉CaO mole ratio of 1꞉2.5, and roasting time of 2.0 h, fluorine and aluminum were separated, with 99.98% of the fluoride solidified and 52.97% of the aluminum extracted. The sodium aluminate products obtained by evaporation and crystallization from leaching solution met the industrial standards of China. The aqueous residue can be used as a raw material for quick-setting cement. Overall, this study provides an effective and environmentally friendly strategy for the treatment of secondary aluminum dross.

Microscopic phase-field method was used to simulate the site occupation of a series of alloys with a stoichiometric composition of Ni75Al25–xFex(x=0, 5–10) aged at 1273 K. With the change of Fe content, quantitative calculations were made on each atomic site occupation probability (SOP) in L12-Ni3(Al1–xFex), so as to find out the dynamic response law. The result of the study shows that, with the increase of Fe content, the Fe atom preferentially occupies the Bsites (corner sites of FCC) with its SOP value being increased gradually, and the SOP of the Al atom on the Bsites is greatly decreased. Meanwhile, AlNiand FeNianti-sites form in the precipitation of L12phase. Moreover, with the increase of Fe content, the formation of AlNiand FeNianti-sites becomes much easier. In addition, it has been found that the instantaneous dynamic evolution of the atomic SOP is completed at the early stage of the growth of L12phases.