Nano-zinc oxide-doped activated carbon from popped rice and its application for feed additive

Abstract

This study synthesized nano-zinc oxide (ZnO)-doped activated carbon based on popped rice. The rice was prepared by heating unmilled rice using hot air to create a porous structure. The popped rice was chemically activated using zinc chloride (ZnCl2) solution at impregnation ratios of ZnCl2 to popped rice (1:1 and 1:2). Pyrolysis was conducted under constant nitrogen flow by raising the temperature at a heating rate of 10°C/min to 800°C and maintaining this temperature for 1 h. The adsorption properties of the activated carbon were investigated using methylene blue (MB). The results of ultraviolet-visible spectroscopy (UV-Vis) showed the prepared activated carbon had a high adsorption capacity of MB that could be compared to that of commercial activated carbon. The structure and morphology of the activated carbon containing ZnO nanoparticles were characterized using raman spectroscopy, field-emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM)/energy-dispersive spectroscopy (EDS). The specific surface area and porosity were analyzed using the Brunauer-Emmett-Teller (BET) method. The ability to bind 3 different types of mycotoxins was evaluated. The outcome indicates that high surface-area-activated carbon with ZnO nanoparticles exhibited the potential to bind aflatoxin B1, zearalenone, and fumonisin B1, which could be used as an animal feed additive.