Fig 1.
Chemical structure of Direct Yellow 27.
Table 1.
Different kinetic, isotherm, and thermodynamic models.
Fig 2.
Determination of point of zero charge (pHpzc) of corncob.
Fig 3.
SEM micrographs of native (A) and DY27-loaded (B) corncob at 1200× magnification.
Fig 4.
Influence of solution pH on DY27 biosorption capacity of corncob.
Fig 5.
Effect of corncob particle size on DY27 biosorption capacity of corncob.
Fig 6.
Influence of initial DY27 concentration on its biosorption capacity of corncob.
Table 2.
Kinetic model parameters for DY27 biosorption onto corncob at different solution pH levels.
Table 3.
Kinetic model parameters for DY27 biosorption onto corncob at different corncob particle sizes.
Table 4.
Kinetic model parameters for DY27 biosorption onto corncob at different initial DY27 concentrations.
Fig 7.
Isotherms of DY27 biosorption by corncob at different temperatures.
Table 5.
Parameters of the isotherm models for the biosorption at 18°C [qm exp: 73.71 ± 4.8 mg g-1].
Table 6.
Parameters of the isotherm models for the biosorption at 35°C [qm exp: 55.79 ± 4.29 mg g-1].
Table 7.
Parameters of the isotherm models for the biosorption at 50°C [qm exp: 38.99 ± 3.9 mg g-1].
Table 8.
Parameters of the isotherm models for the biosorption at 60°C [qm exp: 28.23 ± 1.0 mg g-1].
Table 9.
Thermodynamic parameters for the biosorption.
Fig 8.
FTIR spectra of (A) native corncob, (B) DY27-loaded corncob, and (C) DY27 dye.
Table 10.
Summary of infrared spectral bands observed in the native corncob, DY27-loaded corncob, and DY27 dye.
Fig 9.
CSLM images of a) lignin (green); b) lignin and DY27 dye in green and red colors, respectively; and c) fluorescein-induced fluorescence of corncob proteins in blue color. d) An overlay image showing the interaction between the DY27 dye and the corncob proteins in violet color.
Fig 10.
CSLM images of a) lignin (green); b) DY27 dye on the corncob surface in red color; and c) calcofluor white-induced fluorescence of corncob cellulose in blue color. d) An overlay image showing the interaction between the DY27 dye and the corncob cellulose in violet color.
Fig 11.
Effect of eluents on (A) DY27 desorption and (B) desorption kinetics.