Mechanism of adsorption of cadmium and lead ions by iron-activated biochar

Abstract

Heavy metal removal from aqueous matrices may help reduce disease and cancer incidences. In this study, reed biochar (RBC) and RBC modified by ferrous ammonium sulfate addition (1 mol Fe L-1) were compared for potential Cd and Pb removal from varying pH aqueous solutions. Surface functional groups were identified using Fourier transform infrared (FTIR) analysis, and their surface physicochemical structure was observed using scanning electron microscopy-energy dispersive spectrometry (SEM-EDS). Batch experiments showed that the modified-reed biochar (MRBC) had greater Cd and Pb removal capacities over a wide pH range (1 to 8), as well as greater metal sorption capacities compared to RBC. Metal reaction kinetics occurred relatively quickly (i.e., within 60 min), and Langmuir modeling suggested that Cd and Pb removal by MRBC was maximized at 2.97 mg g−1 and 17.5 mg g−1 at 45 °C, respectively. The MRBC effectively sorbed Cd and Pb likely due to associations with functional groups modified by the Fe addition. In the future, MRBC may be used as an efficient and eco-friendly adsorbent for Cd and Pb removal from aqueous solutions and may help reduce water-borne issues associated with metal contamination.

Effects of excessive impregnation, magnesium content, and pyrolysis temperature on MgO-coated watermelon rind biochar and its lead removal capacity

“…In general, the Pb removal capacities of the MWRBs are outstanding compared with other modified biochars and biochar composites (Table 1). Corncob biochar/montmorillonite composite 400 153 (Fu et al, 2020) H 3 PO 4 pretreated miscanthus sacchariflorus hydrothermal biochar 200 316 (Zhou et al, 2019) Fe-Mn-S/corn straw hydrothermal biochar composite 120 182 (Yang et al, 2019) HCl pretreated date seed biochar 550 189 (Mahdi et al, 2019) Iron activated reed biochar 450 17.5 (Cui et al, 2019) H 3 PO 4 pretreated chicken feather biochar 450 78.4 (Chen et al, 2019a) Urea-functionalized magnetic palm biochar 400 188 (Zhou et al, 2018) Biochar-supported reduced graphene oxide composite 600 34.0 (Zhang et al, 2018b) Eggshell pretreated biochars 450 103-261 (Wang et al, 2018a) Biochar-supported hydrated manganese oxide nanoparticles 400 110 (Wan et al, 2018) Magnetized Douglas fir biochar 900-1000 27 (Karunanayake et al, 2018) Chitosan modified biochar 425 134 (Dewage et al, 2018) Microwave (Yuan et al, 2016) MgCl 2 pretreated sawdust biochar 600 202 (Jellali et al, 2016) NaOH modified hickory wood biochar 600 53.6 (Ding et al, 2016) Manganese-oxide/biochar composite 700 93.4 (Wang et al, 2015a) 3.5 Environmental implications…”

Solvent-Free Synthesis of MnOx-FeOx/Biochar for Hg0 and o-Xylene Removal from Flue Gas

“…FTIR spectra of the as-prepared Mn–Fe-oxides/biochar composites are shown in Figure . The mechanochemical process is reported to be effective in increasing the abundance of functional groups on biochar. , C–H (870 cm –1 ), CO (1595 cm –1 ), and C–O–C (1030 cm –1 ) , peaks were observed in the spectra of the mechanochemical-synthesized MnFe/Char-BM x samples.…”

Changes in surface characteristics and adsorption properties of 2,4,6-trichlorophenol following Fenton-like aging of biochar

“…Survey scan spectra in the 1351–0 eV binding energy range were recorded with a pass energy of 100.0 eV, others in 20.0 eV 13 . The spectra were separated using Systat Peakfit, Version 4.12 (Seasolve, China) 5 .…”

“…Because of the specific surface characteristics (porous structure, micropores etc. ), abundant microchannels and stable aromatic chemical structure (such as alkaline pH and rich organic functional groups) 4 , biochar has been widely used as an environmentally friendly amendment for the treatment of wastewater and soil pollution 5 . For example, wood chip biochar (3–5%, wt) had a high ability to remove 2,4‐dinitrotoluene (DNT) and 2,4‐dichlorophenol (DCP) from an aqueous solution 6 .…”