Influence of interfering anions on Cu²⁺ and Zn²⁺ ions removal on chestnut outer shell-derived hydrochars in aqueous solution

Abstract

Hydrothermal carbonization method was used to produce different hydrochars from chestnut outer shell at various temperatures while resolving the environmental issues of agricultural bio-waste. Hydrochars were adopted as adsorbents to remove heavy metal ions (copper and zinc ions) from aqueous solution. Hydrochar samples were characterized by Scanning Electron Microscope (SEM), Fourier Transform Infrared (FTIR), and Brunauer-Emmett-Teller (BET) nitrogen adsorption-desorption isotherm. An increase in the hydrothermal temperature from 160 °C to 220 °C results in higher BET surface area (18.81 m2 g-1) and the porosity of the samples. The resultant hydrochar at 220 °C exhibited a more excellent adsorption performance (8.13 mg g-1 for copper nitrate) than the other two hydrochars at low hydrothermal temperature. The current study addressed the influence of interfering anions of nitrates, sulfates and chlorides on the adsorption performance. The result shows that the hydrochar possesses larger removal efficiency for heavy metal nitrates that that of chlorides and sulfates

Reuse potential of residues of artichoke (Cynara scolymus L.) from industrial canning processing as sorbent of heavy metals in multimetallic effluents

“…Stock metal solutions (1000 mg•L -1 ) of Cu(II), Cd(II) and Pb(II) were prepared by dissolving the respective metal salts (Cu(NO3)2•3 H2O, Cd(NO3)2•4 H2O, Pb(NO3)2) in Milli Q water. Nitrates salts were used as it has been shown that this counterion is less interfering in the sorption process than sulfates or chlorides (Hong et al, 2017). Working solutions were obtained by diluting the respective stock solution to the desired concentration of 10, 20 and 50 mg/L of each metal ion.…”

Adsorption behaviors on trace Pb2+ from water of biochar adsorbents from konjac starch

“…The main source of biochar raw materials is agricultural biomass (Tan et al., 2015). Banana peel (Anwar et al., 2010), chestnut shell (Hong et al., 2017), corn straw (Yang et al., 2018) and other agricultural wastes were used to prepare for biochar which haves good adsorption effect on heavy metal ions. Many studies have shown that different biochar has a high adsorption capacity for Pb 2+ , and the adsorption performance of biochar is closely related to their structure and composition (Jia et al.2019; Li et al., 2020; Niu et al., 2020).…”