Commercial bentonite (BFN) and organoclay (WS35), as well as iron oxide/clay composite (Mag_BFN) and iron/oxide organoclay
composite (Mag_S35) were prepared for toluene and naphthalene sorption. Mag_BFN and Mag_S35 were obtained, respectively, by
the precipitation of iron oxide hydrates onto sodium BFN and S35 clay particles. The materials were characterized by powder
X-ray diffraction (XRD), X-ray Fluorescence (XRF), and TG and DTA. From XRF results and TG data on calcined mass basis, a
quantitative method was developed to estimate the iron compound contents of the composites, as well as the organic matter
content present in WS35 and Mag_S35.