Novel process for decontamination and additional valorization of steel making dust processing using two-step correlative leaching
Artikel i vetenskaplig tidskrift, 2020

Recycling of steel making dusts often targets Zn removal. Other heavy metals such as Mo, W or Cr do not receive as much attention, and the decontamination of the dusts from these constituents is scarcely addressed in the literature. This study presents a novel approach of the selective separation of Mo from steel making dusts using alkaline solutions with low concentrations, before Zn removal using concentrated alkaline medium. Such an approach has never been reported before and can contribute to more efficient decontamination of the steel making dusts and will increase the value of recovered components since Mo can be significantly preconcentrated. Two samples originating from two steel producers were investigated. One sample contained 2.65% of Mo and 1.87% of Zn, and the second sample had 0.61% of Mo and 35.9% of Zn. Temperature was found to have a low impact on the leaching efficiency of Mo, while increased NaOH concentration promoted leaching of Zn. Excellent pre-concentration of Mo was achieved by using a S:L ratio of 1:3. Almost 5170 mg/L Mo, 1000 mg/L W, no Fe and only 2 mg/L Zn were present in the solution after leaching at 30 °C for 30 min. For the samples containing lower concentrations of Mo and high concentrations of Zn, the selectivity of the process was affected when using higher concentrations of NaOH. A final leachate containing 797 mg/L of Mo and only 11 mg/L Zn was obtained after leaching with 0.05 M NaOH. DFT computations showed that the 2D layered structures of MoO3 and WO3 are decisive factors that account for their high solubilites. © 2019 Elsevier B.V.

Selective recovery

Alkaline leaching

Molybdenum

Steel making dust

Författare

Martina Petranikova

Chalmers, Kemi och kemiteknik, Energi och material, Kärnkemi

Vincent Ssenteza

Cláudio M. Lousada

Kungliga Tekniska Högskolan (KTH)

Burcak Ebin

Chalmers, Kemi och kemiteknik, Energi och material, Kärnkemi

Cristian Tunsu

Chalmers, Kemi och kemiteknik, Energi och material, Kärnkemi

Journal of Hazardous Materials

0304-3894 (ISSN)

Vol. 384 121442

Ämneskategorier

Analytisk kemi

Materialkemi

Metallurgi och metalliska material

DOI

10.1016/j.jhazmat.2019.121442

PubMed

31668760

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Senast uppdaterat

2020-01-08