Water-Dispersible Magnetite-Reduced Graphene Oxide Composites for Arsenic Removal

TLDR

The hybrids exhibit high binding capacity for As(III) and As(V), addressing a major arsenic contamination problem in South Asian drinking water. The hybrids are synthesized by a chemical reaction yielding ~10 nm magnetite particles, and their high binding capacity arises from increased adsorption sites that reduce magnetite aggregation. The composites are superparamagnetic, enabling magnetic separation, and achieve >99.9 % arsenic removal at 1 ppb, making them practically usable for water treatment.

Abstract

Magnetite−graphene hybrids have been synthesized via a chemical reaction with a magnetite particle size of ∼10 nm. The composites are superparamagnetic at room temperature and can be separated by an external magnetic field. As compared to bare magnetite particles, the hybrids show a high binding capacity for As(III) and As(V), whose presence in the drinking water in wide areas of South Asia has been a huge problem. Their high binding capacity is due to the increased adsorption sites in the M−RGO composite which occurs by reducing the aggregation of bare magnetite. Since the composites show near complete (over 99.9%) arsenic removal within 1 ppb, they are practically usable for arsenic separation from water.