Effect of treatment with acetic acid and size-fractionation of a raw clay on its chemical and physical properties and aflatoxin B۱ (AFB۱)-adsorption capacity

In this study, the effect of particle size of raw and modified bentonite on aflatoxin B۱ (AFB۱) absorption was investigated. Sample was treatment with acetic acid and the size fractionation of clays (raw bentonite and remove calcium carbonate) were performed by centrifuge. Absorption of AFB۱ was determined in concentration (۱.۶ mg/l) by spectrophotometer. According to XRD analyses results montmorillonite was the dominant clay mineral and dolomite and kaolinite were the associate minerals. Among all samples, the particles size <۲μm modified had the highest cation exchange capacity and adsorption capacity. But the sizes of particles had no considerable influence on AFB۱-adsorption capacity. Adsorption capacity was probably low due to the presence of crystals of free iron oxides which act as cementing factors in particles of clay.