Ziziphus spina-christi leaves biochar decorated with Fe3O4 and SDS for sorption of chromium (III) from aqueous solution

• Published in: Biomass conversion and biorefinery Vol. 14; no. 9; pp. 10251 - 10264
• Main Authors: Shiraghaei Koutenaei, Shima, Vatankhah, Gholamhossein, Esmaeili, Hossein
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-05-2024; Springer Nature B.V
• Subjects: Aqueous solutions; Biotechnology; Correlation coefficients; Electron microscopy; Energy; Fourier transforms; Infrared spectroscopy; Ion concentration; Iron oxides; Light diffraction; Microscopy; Nanocomposites; Original Article; Photon correlation spectroscopy; Renewable and Green Energy; Sorption; Spectrum analysis; Trivalent chromium; X-ray diffraction; Sorption; Cr(III) ions; Aqueous solution; @SDS nanocomposite; Biochar@Fe; O
• ISSN: 2190-6815; 2190-6823
• DOI: 10.1007/s13399-022-03029-4

The purpose of this study was to remove Cr(III) ions from aqueous solution using biochar@Fe
3
O
4
@SDS nanocomposite. Biochar@Fe
3
O
4
@SDS was synthesized as a novel adsorbent by chemical co-precipitation method. The structural features of the nanocomposite were investigated using energy-dispersive spectroscopy (EDS), dynamic light scattering (DLS), X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) analyses. The BET surface area and the mean pore diameter of the biochar@Fe
3
O
4
@SDS were 102.04 m
2
/g and 169.49°A, respectively, indicating the high porosity of the aforementioned nanocomposite. DLS and XRD analyses showed that the mean particle size and crystal size of biochar@Fe
3
O
4
@SDS are 78.9 nm and 28 nm, respectively. Also, the highest Cr(III) removal efficiency (99.5%) using biochar@Fe
3
O
4
@SDS was obtained at pH = 9, contact time = 40 min, temperature = 55 ºC, the Cr(III) ion concentration = 10 mg/L, and the nanocomposite dosage = 2 g/L. Moreover, the maximum sorption capacity obtained from the Langmuir model was 120.48 mg/g, which is a significant value compared to previous studies for Cr(III) removal. Furthermore, the isotherm study indicated that the Cr(III) sorption process using the aforementioned nanocomposite followed the Freundlich models due to the higher correlation coefficient (0.986). Also, the pseudo-second order kinetic model with a correlation coefficient of 1 was better fitted than the pseudo-first order model with experimental data. Subsequently, the thermodynamic study demonstrated that the sorption process of Cr(III) ions using biochar@Fe
3
O
4
@SDS is favorable, feasible, spontaneous, and endothermic.