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In order to utilize blast furnace slag resource at low cost, pollution-free, refinement and high value-added, a novel technical route was proposed to collaboratively produce zeolite and hydrotalcite-like compound. In this study, the changing property of slag in the treatment process was investigated and the thermodynamic and kinetic analyses of the leaching reaction were conducted to prove its feasibility. The silica gel and residue liquid were separated effectively from the slag. Then, 13X zeolite and hydrotalcite-like compound were successfully synthesized from water quenching blast furnace slag using hydrochloric acid treatment followed by hydrothermal method and co-precipitation method. The successful formation of 13X zeolite and hydrotalcite-like compound were obtained effectively with good surface morphology and crystal structure. Mass balance of the blast furnace slag utilization process was established. Meanwhile, these two samples exhibited good behavior of CO 2 adsorption capacity and enjoyed a promising market prospect. The maximum adsorption capacities of 13X zeolite and hydrotalcite-like compound were 116.48 mg g−1 at 313 K and 149.63 mg g−1 at 873 K, respectively. Finally, the preliminary economic evaluation of the integrated system was conducted, and the economic benefit of 1 kg slag was about 1.281 $. [Display omitted] • A novel resource utilization method of the blast furnace slag was proposed. • 13X zeolite and hydrotalcite-like compounds could be produced collaboratively. • The technology prototype combined slag utilization and CO 2 sequestration was established. • The new technology achieves the objective of high value-added resources production. [ABSTRACT FROM AUTHOR]

The resource utilization of blast furnace slag was the research hotspot at home and abroad. This study aimed to obtain hydrotalcite-like compounds from slag using co-precipitation method. The optimum process conditions for the synthesis of hydrotalcite-like compounds were investigated using single-factor in a self-designed laboratory-scale system. Furthermore, the synthesis mechanism of hydrotalcite-like compounds was established. The pH of 11.5, precipitation temperature of 343 K, crystallization temperature of 383 K, and crystallization duration of 6– 10 h were shown to be the optimum process conditions for the synthesis of hydrotalcite-like compounds. The leachate formed a typical crystal layered structure of hydrotalcite-like compounds under optimum process conditions through chemical reactions between compounds and sufficient crystallization. The completion of this work provided a new technological path for the utilization of blast furnace slag, which was more conducive to the energy saving and emission reduction of the iron and steel industry. [Display omitted] • A novel resource utilization method of the blast furnace slag was proposed; • Optimum process conditions for the synthesis of hydrotalcite-like compounds were derived; • The synthesis mechanism of hydrotalcite-like compounds by using slag as raw material was established. [ABSTRACT FROM AUTHOR]