Fig 1.
SEM image of (a) Original dry sludge, (b) SBC, (c) MgSP-0.1 and (d) MgSBC-0.1, respectively.
Fig 2.
(a) N2 adsorption and desorption curve, (b) XRD patterns of SP, SBC and MgSBC-0.1 and (c) XPS spectra of SP, SBC, and MgSBC-0.1.
Table 1.
Elemental composition (Atomic%) and oxygen carbon atomic ratio of SP, SBC, P-MgSBC-0.1 and Des-MgSBC-0.1 estimated by X-ray photoelectron spectroscopy (XPS).
Fig 3.
(a-c) TEM images (500nm) of SP, SBC and MgSBC-0.1, (d-e) TEM images of MgSBC-0.1, (f-i) Elemental mapping of MgSBC-0.1.
Fig 4.
FTIR spectra of SP, SBC, and MgSBC-0.1.
Fig 5.
The effect of magnesium loading on the adsorption of P by Mg-loaded sludge-biochar.
Fig 6.
The phosphate adsorption isotherms and the kinetic curve (a and b) The fitting the phosphate adsorption isotherms of MgSBC-0.1 at different temperatures, (c) the kinetic curve of MgSBC-0.1, (d) particle diffusion model fitting of MgSBC-0.1.
Table 2.
Adsorption kinetics parameters of MgSBC-0.1.
Table 3.
Isothermal adsorption model parameters of MgSBC-0.1 at 298, 308, and 318 K, respectively.
Fig 7.
The effect of initial pH on phosphate capture.
Fig 8.
(a) The effect of coexisting anions on phosphate capture and (b) the effect of coexisting cations and gumic acids on phosphate capture.
Fig 9.
(a) XRD spectrum of P-MgSBC-0.1 biochar, (b) XPS spectra of MgSBC-0.1, P-SBC, and P-MgSBC-0.1, (c) XPS spectra of Mg 1s before utilization and (d) after utilization phosphate adsorption of MgSBC-0.1, respectively.