As(III) removal by a recyclable granular adsorbent through dopping Fe-Mn binary oxides into graphene oxide chitosan

New sulfonated covalent organic framework for highly effective As(III) removal from water

“…The absorption of As(III) ions by TFPOTDB-SO 3 H was examined at various temperatures, from 298 to 323 K. The study found that with an increase in temperature, there was a corresponding increase in adsorption, suggesting that the uptake process is heat-absorbing. This finding agrees with previous studies [ [56] , [57] , [58] ] ( Fig. S3 ).…”

Biopolymeric Nanocomposites for Wastewater Remediation: An Overview on Recent Progress and Challenges

“…This process coincides with the oxidation of As(III) to As(V), catalyzed by O 2 and MnO 2 , followed by complexation with Fe-O groups. Additionally, a minor fraction of As is adsorbed through complexation with oxygen-containing functional groups, such as -OH and single -COOH, present in the chitosan-GO-based nanocomposite ( Figure 11 ) [ 179 ]. Similarly, Zheng et al has developed the composite nanofiber membrane based on the modified chitosan as carboxymethyl chitosan with a synthetic biodegradable polymer, polyvinyl alcohol, PVA, and GO by using the electrospinning method for the adsorption of heavy metal ions (Ni 2+ , Cu 2+ , Ag + , and Pb 2+ ).…”

“… Schematic illustration of mechanism of removal of As (III) by using binary-doped Fe-Mn with chitosan-GO granular adsorbent [ 179 ]. …”

Understanding the role of manganese oxides in retaining harmful metals: Insights into oxidation and adsorption mechanisms at microstructure level

“…Natural Mn oxides, with their low point of zero charge (PZC), large surface area, high negative charge, and high reduction potential, are key in controlling harmful metal concentrations, especially heavy metals, through adsorption, coprecipitation, and redox reactions [ 2 , 5 , 18 , [44] , [45] , [46] , [47] , [48] , [49] , [50] , [51] ]. Compared to traditional adsorbents like aluminum (Al) oxides, iron (Fe) oxides, green clay polymer sulfur, and carbon-based materials, Mn oxides offer superior adsorption efficiency and stability for metal removal from water [ [52] , [53] , [54] , [55] , [56] ]. They exhibit greater adsorption capacities for toxic metals like copper (Cu), cobalt (Co), nickel (Ni), zinc (Zn), lead (Pb), and cadmium (Cd) than Al oxides and Fe oxides [ [57] , [58] , [59] ].…”