Fig. 1. Adsorption efficiency of heavy metal Cr by Chlorella pyrenoidosa at different reaction time

Fig. 2. Adsorption efficiency of heavy metal Cr by Chlorella pyrenoidosa at different pH

Fig. 3. Activity of Chlorella pyrenoidosa. (a) Relationship between temperature and activity of Chlorella pyrenoidosa; (b) effect of activity of Chlorella pyrenoidosa on adsorption of heavy metal Cr

Fig. 4. Adsorption efficiencies of heavy metal Cr under different mass concentrations of Chlorella pyrenoidosa

Fig. 5. Adsorption of Chlorella pyrenoidosa to different concentrations of heavy metal Cr

Fig. 6. Characteristic XRF spectra of different mass concentrations of heavy metal Cr enriched by Chlorella pyrenoidosa

Fig. 7. Calibration curve of Kα characteristic line integral fluorescence intensity of Cr versus Cr mass concentration

Fig. 8. Variation of XRF spectra in surface water sample addition and recovery experiment. (a) Main spectral lines; (b) Kα characteristic lines of Cr