标题: High efficiency selective recovery of Al from high-alumina fly ash by multistage activation and carbonation on-site application scale

作者: Zhang, SS (Zhang, Shanshan); Yu, LJ (Yu, Lijie); Lv, Y (Lv, Yi); Zeng, TY (Zeng, Tianyu); Hou, HB (Hou, Haobo); Lan, JR (Lan, Jirong)

来源出版物: CHEMICAL ENGINEERING JOURNAL 卷: 506 文献号: 160003 DOI: 10.1016/j.cej.2025.160003 Early Access Date: JAN 2025 Published Date: 2025 JAN 15

摘要: A method of calcination activation-chemical separation-carbonization precipitation was developed for selective recovery of Al from high-alumina fly ash (HAFA). Specifically, calcium carbide slag, CaF2 and HAFA were used for mechanical mixing and calcination, and then, Al was leached with sodium carbonate solution, followed by the use of CaO to separation and removal of Si, the next step of filtration to remove the residue to obtain, and finally, the precipitation recovery of Al was realized by the passage of CO2 into the solution. Consequently, the formation of soluble calcium aluminate (C12A7) and insoluble dicalcium silicate (C2S) is promoted, effectively achieving the separation of silicon and aluminum during the calcination process. Desiliconization and carbonation of the leaching solution yielded aluminum hydroxide with a conversion rate of 96.67 % and a purity of 98.40 %. Pilot-scale experiments achieve an overall aluminum extraction rate of over 80 % and an aluminum purity of 98 %. In addition, the process absorbs 0.564 tons of CO2 per ton of Al(OH)3 produced. This study highlights the feasibility of large-scale collaborative carbon sequestration and efficient HAFA resource treatment.

作者关键词: High-alumina coal fly ash; Alumina extraction; Calcination; Waste utilization; Alumina production

KeyWords Plus: CALCIUM ALUMINATE; EXTRACTION; TRANSITION; MULLITE; WASTE

地址: [Zhang, Shanshan; Yu, Lijie; Zeng, Tianyu; Hou, Haobo] Wuhan Univ, Sch Resource & Environm Sci, Wuhan 430072, Peoples R China.

[Hou, Haobo] Zhaoqing Wuhan Univ, Environm Technol Res Inst, Zhaoqing 526200, Guangdong, Peoples R China.

[Lan, Jirong] Hong Kong Polytech Univ, Dept Civil & Environm Engn, Hong Kong 999077, Peoples R China.

[Lv, Yi] China Three Gorges Corp Sci & Technol Res Inst, Wuhan 430010, Peoples R China.

通讯作者地址: Hou, HB (通讯作者)，Wuhan Univ, Sch Resource & Environm Sci, Wuhan 430072, Peoples R China.

Lan, JR (通讯作者)，Hong Kong Polytech Univ, Dept Civil & Environm Engn, Hong Kong 999077, Peoples R China.

电子邮件地址: houhb@whu.edu.cn; jironglan@whu.edu.cn

影响因子：13.4