Mesoporous Silica Nanoparticles for the Uptake of Toxic Antimony from Aqueous Matrices
Xiuzhen Yang, Bin Zhou, Changye Wang, Ronghao Tan, Shuangchan Cheng, Atif Saleem, Yuezhou Zhang
Abstract
High Resolution Image Download MS PowerPoint Slide Contamination of water sources by toxic antimony Sb(III) ions poses a threat to clean water supplies. In this regard, we have prepared a mesoporous silica nanoparticle (MSN)-derived adsorbent by reverse microemulsion polymerization, using cetyltrimethylammonium chloride (CTAC) and triethanolamine (TEA) as co-templates. The physical and chemical properties were characterized using advanced tools. The MSN exhibits a higher surface area of up to 713.72 m 2 ·g –1, a pore volume of 1.02 cm 3 ·g –1, and a well-ordered mesoporous nanostructure with an average pore size of 4.02 nm. The MSN has a high adsorption capacity for toxic Sb(III) of 27.96 mg·g –1 at pH 6.0 and 298 K. The adsorption data followed the Langmuir isotherm, while the kinetics of adsorption followed the pseudo-second-order model. Interestingly, the effect of coexisting iron showed a promoting effect on Sb(III) uptake, while the presence of manganese slightly inhibited the adsorption process. The recyclability of the MSN adsorbent was achieved using a 0.5 M HCl eluent and reused consecutively for three cycles with a more than 50% removal efficiency. Moreover, the characterization data and batch adsorption study indicated physical adsorption of Sb(III) by mesopores and chemical adsorption due to silicon hydroxyl groups.