Interaction of environmental factors on simultaneous biosorption of lead and manganese ions by locally isolated Bacillus cereus

•Simultaneous biosorption of Pb and Mn using native Bacillus cereus.•Effect of environmental factors on the simultaneous biosorption Pb and Mn.•Interaction between the environmental factors on the simultaneous biosorption.•Lagergren and Langmuir models were best fitted for the simultaneous biosorption.•Pb and Mn were precipitated and transported through the cell wall of Bacillus cereus.

In this study, the interaction of pH, biomass and initial concentrations of lead (Pb) and manganese (Mn) ions in simultaneous removal of Pb and Mn were investigated using the Box–Behnken design. The results showed that there was a significant interaction between pH-Pb:Mn concentrations, pH-biomass concentration and Pb:Mn-biomass concentrations. The maximum uptake of Pb and Mn was achieved at pH 7. By increasing the Pb and Mn concentrations from 10 to 50 mg/L, the uptake capacities also increased. By increasing the biomass concentration from 0.3 to 1.5 g/L, the uptakes (g/g) of both metal ions by Bacillus cereus I6 was depleted. The precipitation of Pb and Mn on the surface of B. cereus I6 cells was confirmed by energy dispersive X-ray (EDX) transmission electron microscopy (TEM), and Fourier transform infrared (FTIR). Thus, simultaneous biosorption of Pb and Mn by isolated I6 strain can be efficiently performed under different interactions of environmental factors.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide