Arsenic removal from water using a one-pot synthesized low-cost mesoporous Fe-Mn-modified biosorbent

Abstract

This paper investigates the removal of arsenic from water using an environmentally friendly modified biosorbent, chitosan coated with Fe-Mn binary oxide (Chit-FeMn), simply prepared with an one-pot low-cost procedure by simultaneous oxidation and coprecipitation. The sorbent was characterized by SEM, EDS, XRD, FTIR, BET specific surface area, and point of zero charge (pH pzc) measurements. The kinetic data fitted a pseudo-second order model for both As(III) and As(V), suggesting chemical adsorption on the sorbent surface and that intra-particle diffusion is not the only rate-limiting step during adsorption. The adsorption isotherms were best fit to the Freundlich model, and the non-monolayer adsorption model for arsenic on Chit-FeMn is therefore proposed. Below pH 9, the effect of pH on As(III) and As(V) removal by Chit-FeMn was insignificant, with As removals remaining above 85 %. Cland NO 3 had negligible influences on As(III) and As(V) removal, whereas PO 4 3-, SiO 3 2-, CO 3 2and SO 4 2were observed to compete with arsenic species for adsorption sites. The adsorbent was successfully applied to remove arsenic from real arsenic contaminated groundwater samples to below 10 µg L-1 suggesting that Chit-FeMn is a promising candidate for the low cost removal of both As(V) and As(III) during drinking water treatment.

Hollow Polyaniline Microsphere/Fe3O4 Nanocomposite as an Effective Adsorbent for Removal of Arsenic from Water

“…In contrast, there exist unfavorable electrostatic interactions between the non-ionic As(III) species and the positively charged adsorbent surface. Thus, good removal of As(III) in our case may be due to the oxidation reaction of As(III) to As(V) followed by sorption on the positive surface of PNHM/Fe 3 O 4 -40 45,46 . Alternatively, the possibility of adsorption of As(III) on the surface of PNHM/Fe 3 O 4 -40 via surface complexation rather than electrostatic interactions also cannot be ruled out 47 .…”

Enhancement of Uranium Recycling from Tailings Caused by the Microwave Irradiation-Induced Composite Oxidation of the Fe–Mn Binary System

“…However, the appropriateness of the SCM model sharply deteriorated in the middle and late stages of the leaching experiments (i.e., particularly after 60 min) with the increase of Fe­(III) concentrations and the participation of Mn­(VII). The unleached solid cores in the U tailing particles had endured a reverse increase after the first shrink process over time, which may be subjected to the re-desorption and surface covering caused by the formation of some new Fe–Mn species during the experiments. , …”

“…Some bands at 576, 617, 887, and 1290 cm −1 were formed after the sequential experiments, which explained the participation of oxidants and the generation of derived Fe and Mn species. 65,75,76 Fewer peaks were found in the spectrum of specimens acquired from the coupling experiments. The MW combined with oxidant participation was more conducive to strengthening the effect of acid leaching on the U extraction from the U tailing specimens.…”

“…The unleached solid cores in the U tailing particles had endured a reverse increase after the first shrink process over time, which may be subjected to the re-desorption and surface covering caused by the formation of some new Fe−Mn species during the experiments. 65,66 3.4. Explorations of Reaction Mechanisms.…”

Preparation of PVDF/FMBO composite electrospun nanofiber for effective arsenate removal from water

“…This process continues until the nanocomposite As(V) adsorption capacity stops. 49,50 The isotherm experiments were conducted to evaluate adsorption capacities of the PVDF NFs in the absence and presence of FMBO adsorbent showed in Fig. 6.…”