Removal of Arsenic (III, V) from aqueous solution by nanoscale zero-valent iron stabilized with starch and carboxymethyl cellulose

Abstract

In this work, synthetic nanoscale zerovalent iron (NZVI) stabilized with two polymers, Starch and Carboxymethyl cellulose (CMC) were examined and compared for their ability in removing As (III) and As (V) from aqueous solutions as the most promising iron nanoparticles form for arsenic removal.Batch operations were conducted with different process parameters such as contact time, nanoparticles concentration, initial arsenic concentration and pH.Results revealed that starch stabilized particles (S-nZVI) presented an outstanding ability to remove both arsenate and arsenite and displayed ~ 36.5% greater removal for As (V) and 30% for As (III) in comparison with CMC-stabilized nanoparticles (C-nZVI). However, from the particle stabilization viewpoint, there is a clear trade off to choosing the best stabilized nanoparticles form. Removal efficiency was enhanced with increasing the contact time and iron loading but reduced with increasing initial As (III, V) concentrations and pH. Almost complete removal of arsenic (up to 500 μg/L) was achieved in just 5 min when the S-nZVI mass concentration was 0.3 g/L and initial solution pH of 7 ± 0.1. The maximum removal efficiency of both arsenic species was obtained at pH = 5 ± 0.1 and starched nanoparticles was effective in slightly acidic and natural pH values. The adsorption kinetics fitted well with pseudo-second-order model and the adsorption data obeyed the Langmuir equation with a maximum adsorption capacity of 14 mg/g for arsenic (V), and 12.2 mg/g for arsenic (III).It could be concluded that starch stabilized Fe0 nanoparticles showed remarkable potential for As (III, V) removal from aqueous solution e.g. contaminated water.

Polymeric Nanocomposites of Iron–Oxide Nanoparticles (IONPs) Synthesized Using Terminalia chebula Leaf Extract for Enhanced Adsorption of Arsenic(V) from Water

“…Polyvinyl alcohol (PVA) showed mechanical and chemical stability over other polymers and also possessed excellent adsorption capacity for the removal of toxic pollutants [50,65]. Ascorbic acid-coated Fe3O4 nanoparticles 16.56 mg/g pH = 7, 300 K, 60 mg/L adsorbent [60] Starch and Carboxymethyl cellulose (CMC) zerovalent iron 14 mg/g Adsorbent = 100-1000 mg/L, As = 2 mg/L, pH= 7 [61] Zero valent iron reduced graphene 29.04 mg/g 10 mg adsorbent, As(V) = 1-15 ppm, pH = 7.0 [62] Montmorillonite-supported nanoscale zero-valent iron 45.5 mg/g As = 5-250 mg/L, Adsorbent = 1 g/L, pH = 7 [63] Chitosan nanocompositesmagnetic nanoparticles 35.7 mg/g Adsorbent = 1 g/L, pH = 6.8 [24] Plant-synthesized IONPs chitosan hybrid 147 ± 7 mg/g As(V) = 300-8000 µg/L, Adsorbent = 25 g/L [64]…”

Removal of Heavy Metals from Industrial Waste Water by Biomass-Based Materials: A Review

“…Very recently, synthetic nanoscale zerovalent iron (NZVI) stabilized with two polymers, Starch and Carboxymethyl cellulose (CMC) were investigated and compared for their capability in removing As (III) and As (V) from aqueous solutions as the most promising iron nanoparticles form for arsenic removal [79]. Furthermore, [80] studied the removal of copper (II) and lead(II) ions from aqueous solutions by Starch-graftacrylic acid/montmorillonite (S-g-AA/MMT) Nanocomposite.…”

Application of Stabilized Nanoparticles for In Situ Remediation of Metal-Contaminated Soil and Groundwater: a Critical Review

“…Starch stabilization was also found to enhance ZVI's ability for arsenic removal from aqueous solutions [38]. Kanel et al [39] also reported that polyoxyethylene sorbitan monolaurate-stabilized ZVI nanoparticles can effectively remove As(III) from water.…”