Harnessing Magnetite Poly(ethylene Glycol)-Block-Poly(propylene Glycol)-Block-Poly(ethylene Glycol) (PEG-PPG-PEG) Composites for Efficient Arsenic Removal in Water Treatment

Abstract

Elevated arsenic levels in soil and water resources due to improper waste management by industry cause detrimental impacts on the environment and human health due to its carcinogenicity and high toxicity. This work demonstrated a facile and scalable method for the synthesis of γ-Fe2O3-PEG-PPG-PEG composites for practical arsenic adsorption. The synthesis of γ-Fe2O3-PEG-PPG-PEG composites resulted in a high percentage yield of 91.4%. Morphological analyses confirmed the microstructures and crystallinity of γ-Fe2O3-PEG-PPG-PEG composites. Besides, HR-TEM showed a homogeneous distribution of γ-Fe2O3 nanoparticles with an average particle size of 25 nm. The peak at 452 cm−1 in FT-IR spectra corresponds to the Fe–O stretching vibration, thus confirming the presence of γ-Fe2O3 nanoparticles. The synthesized composites showed increasing surface area (31–117 m2/g) and thermal stability with increasing γ-Fe2O3 nanoparticle compositions. The As(V) batch adsorption study revealed efficient As(V) removal up to 56.5 µg/g determined by the Langmuir adsorption isotherm. Furthermore, the equilibrium adsorptions were attained between 30 and 120 min. Notably, the adsorption capacity of the γ-Fe2O3-PEG-PPG-PEG composites increased significantly as the As(V) initial concentration increases. The research findings showed that the γ-Fe2O3-PEG-PPG-PEG composites could be potential adsorbents to treat arsenic-contaminated wastewater. Besides, the synthesized composites were proven to be economical and practical for scaling up due to their high product yield.