Removal of antimonite and antimonate in aqueous solution by mugwort biochar modified by Acidithiobacillus ferrooxidans after pyrolysis

In the research, iron oxides-biochar composites (ALBC) were prepared from pristine biochar modified by Acidithiobacillus ferrooxidans (A. ferrooxidans) and pyrolyzed at 500 degrees C and 700.C in order to remove antimonite (Sb (III)) and antimonate (Sb(V)) from water. The results indicated that biochar prepared at 500 degrees C and 700 degrees C (ALBC500 and ALBC700) were loaded with Fe2O3 and Fe3O4, respectively. In bacterial modification systems, ferrous iron and total iron concentrations decreased continuously. The pH values of bacterial modification systems including ALBC500 increased first and then decreased to a stable state, while the pH values of bacterial modification systems with ALBC700 continued to decrease. The bacterial modification systems can facilitate the formation of more jarosites by A. ferrooxidans. ALBC500 had optimal adsorbing capacities for Sb(III) (18.81 mg center dot g(-1)) and Sb(V) (14.64 mg center dot g(-1)). The main mechanisms of Sb(III) and Sb(V) adsorption by ALBC were electrostatic interaction and pore filling.

Automated summary

In this study, iron oxides-biochar composites (ALBC) were prepared by modifying pristine biochar with Acidithiobacillus ferrooxidans (A. ferrooxidans) and pyrolyzing it at 500°C and 700°C to remove antimonite (Sb (III)) and antimonate (Sb(V)) from water. The results showed that biochar prepared at 500°C and 700°C (ALBC500 and ALBC700) contained Fe2O3 and Fe3O4, respectively. The bacterial modification systems decreased the concentrations of ferrous iron and total iron. The pH values of the systems with ALBC500 increased first and then stabilized, while the systems with ALBC700 continued to decrease. The optimal adsorption capacities for Sb(III) and Sb(V) were achieved by ALBC500 (18.81 mg center dot g(-1)) and ALBC (14.64 mg center dot g(-1)), respectively. The main mechanisms of Sb(III) and Sb(V) adsorption by ALBC were electrostatic interaction and pore filling.