Preparation of polymeric aluminum ferric sulphate from waste residue of aluminum industry

Li Jun,Ju Yanmei,T Zhu,M Anpo,A Sharifi

doi:10.1051/e3sconf/202127104005

Li Jun, Ju Yanmei + Show 3 more

Open Access

https://doi.org/10.1051/e3sconf/202127104005

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Abstract

Polymeric aluminum ferric sulphate(PAFS) was prepared from high-sulfur bauxite flotation tailings and red mud by roasting, acid leaching and polymerization. The effects of leaching temperature, leaching time, liquid-solid ratio on the leaching rate of Al3+ and Fe3+were investigated. The optimal leaching conditions are as follows: leaching temperature 100℃, leaching time 90 min, sulfuric acid concentration 4.5mol/L and liquid-solid ratio 5 mg/L. Infrared spectroscopy and X-ray diffraction analysis was carried out on the PAFS prepared under the optimum process parameters. The characterization of PAFS shows that the synthesized PAFS had polymeric aluminum, iron and hydroxyl structures. Wastewater disposal test of synthetic PAFS shows that the removal rates of COD, turbidity and chromaticity are 45.61%, 75% and 94.18%, respectively.

Highlights

High-sulfur bauxite flotation tailings is a kind of solid waste discharged from the bauxite ore beneficiation process[1]
Optimization of acid leaching process The flue gas generated during the roasting of high sulfur bauxite flotation tailings is absorbed by the red mud slurry
3.1.1 Effect of temperature on leaching rate of Al3+ and Fe3+ The relationship between leaching rate of aluminum and iron and temperature is shown in Fig.4, which was obtained under the conditions of sulfuric acid concentration of 5.30 mol/L, liquid-to-solid ratio of 6 mL/g, and reaction time of 90 min

Summary

Introduction

High-sulfur bauxite flotation tailings is a kind of solid waste discharged from the bauxite ore beneficiation process[1]. There are still problems such as low value-added products or high process energy consumption or limited solid waste consumption, resulting that most of produced red mud and bauxite flotation tailings are stored in landfills[12]. As shown in Fig., goethite, hematite, quartz, and boehmite were identified as main phases of red mud; diaspora, pyrite, illite, kaolinite, and anatase were identified as main phases of high-sulfur bauxite flotation tailings. Materials High-sulfur bauxite flotation tailings and red mud were collected from an alumina plant of Chinalco, composed of particles less than 100 screen mesh. The water bath apparatus is shown in Fig., which is used to leach aluminum and iron from the waste slags. 1- Thermostatic water bath; 2- Beaker; 3- Stirrer; 4- Contact thermometer; 5- Control box Figure 2 Schematic diagram of aluminum and iron leaching experimental device

Experimental method

Results and discussion

Conclusions