Effect of Calcination Temperature on the Structure of Chitosan-Modified Montmorillonites and their Adsorption of Aflatoxin B1

Abstract

AbstractChitosan (CTS) modified montmorillonite (Mnt) composites (CTS-Mnt), which have been widely reported for the adsorption of heavy-metal ions and biological dyes, have not been applied to the field of mycotoxin adsorption. The current study was focused on the preparation of CTS-Mnt by calcination as a mycotoxin adsorbent for the efficient removal of aflatoxin B1 (AFB1). The CTS-Mnt samples obtained were characterized using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and nitrogen adsorption/desorption analysis. The CTS-Mnt samples prepared at various calcination temperatures exhibited varying structural configurations, surface hydrophobicities, and texture properties. The results revealed that stable CTS-Mnt speciments, obtained at <350°C, displayed superior adsorption capacity for AFB1 from a simulated gastrointestinal tract, increasing from 0.51 mg/g of raw Mnt to 4.97 mg/g. With increased calcination temperature, the effect of pH on the adsorption process of AFB1 becomes negligible. This study demonstrates that the novel CTS-Mnt has tremendous potential as an AFB1 adsorbent.