Removal of aflatoxin B from aqueous solution using amino-grafted magnetic mesoporous silica prepared from rice husk.

It is urgent to solve the contamination of aflatoxin B (AFB) in food and water. In this study, the mesoporous silica was prepared from rice husk, which was then magnetized using the precipitation technique, followed by amino-modification with 3-aminopropyltriethoxysilane, forming amino-grafted magnetic mesoporous silica (NMMS). X-ray diffraction, Fourier transformed infrared spectra, and thermogravimetric analysis showed the successful grafting of amino groups on NMMS with a percentage of grafting up to 13.33%. The NMMS had an adsorption capacity of 169.88 μg/g and a removal rate of 93.43% for AFB in aqueous solutions at 20 °C, pH 7.0 for 2.0 h. The adsorption of AFB by NMMS followed a quasi-second-order kinetics and fitted well with the Langmuir model. Furthermore, the removal rate of AFB by NMMS remained 72.43% after repeating the adsorption-desorption process for five times. This study provided a facile approach to prepare NMMS for effective removal of AFB.