Synthesis and characterization of cellulose-goethite composites and their adsorption properties with roxarsone

This study reports on the preparation of goethite and its supported forms onto cellulose as adsorbents for the adsorption of 4-hydroxy-3-nitrobenzene arsenic acid (roxarsone) from aqueous solution. Goethite nanoparticles (NPs) and their cellulose composites were prepared with good yield ∼97%, and characterized by thermal gravimetric analysis (TGA), Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, nitrogen gas adsorption/desorption (BET), powder X-ray diffraction (pXRD) and transmission electron microscopy (TEM). The monolayer uptake (Q_m) capacity of goethite was 19.2mg/g while the Q_m value for 30% Fe coated goethite-cellulose (GC) was 17.4mg/g. The greater content and dispersion of goethite NPs contribute active sites on the cellulose surface to yield greater uptake of roxarsone for the Fe loaded GC composites. GC composites are a cost effective and efficient way to disperse goethite NPs onto cellulose surface for the enhanced adsorption of roxarsone. The GC composites reduce NP leaching whilst maintaining comparable uptake of arsenic species at 30% iron oxide doping that rival the adsorption properties of the pure mineral phase of goethite.