Instituto Potosino de Investigación Científica y Tecnológica A.C., División de Ciencias Ambientales, Camino a la Presa San José 2055, Col. Lomas 4a sección, San Luis Potosí SLP 78216, Mexico.
J Hazard Mater. 2013 Feb 15;246-247:300-9. doi: 10.1016/j.jhazmat.2012.12.001. Epub 2012 Dec 20.
The effect of iron particle size anchored on the surface of commercial activated carbon on the removal of SO(2) from a gas phase was studied. Nanosize iron particles were deposited using forced hydrolysis of FeCl(3) with or without H(3)PO(4) as a capping agent. Dynamic adsorption experiments were carried out on either dry or pre-humidified materials and the adsorption capacities were calculated. The surface of the initial and exhausted materials was extensively characterized by microscopic, porosity, thermogravimetric and surface chemistry. The results indicate that the SO(2) adsorption capacity increased two and half times after the prehumidification process owing to the formation of H(2)SO(4) in the porous system. Iron species enhance the SO(2) adsorption capacity only when very small nanoparticles are deposited on the pore walls as a thin layer. Large iron nanoparticles block the ultramicropores decreasing the accessibility of the active sites and consuming oxygen that rest adsorption centers for SO(2) molecules. Iron nanoparticles of about 3-4 nm provide highly dispersed adsorption sites for SO(2) molecules and thus increase the adsorption capacity of about 80%. Fe(2)(SO(4))(3) was detected on the surface of exhausted samples.
研究了负载在商业活性炭表面的铁颗粒粒径对气相中 SO(2)去除的影响。采用 FeCl(3)的强制水解法，在有无 H(3)PO(4)作为封端剂的情况下沉积纳米铁颗粒。在干燥或预加湿的材料上进行动态吸附实验，并计算吸附容量。通过微观、孔隙率、热重和表面化学等方法对初始和耗尽材料的表面进行了广泛的表征。结果表明，由于多孔体系中形成了 H(2)SO(4)，预加湿过程后 SO(2)吸附容量增加了两倍半。只有当非常小的纳米颗粒作为薄涂层沉积在孔壁上时，铁物种才会增强 SO(2)的吸附能力。大的铁纳米颗粒会堵塞超细孔，降低活性位的可及性，并消耗用于 SO(2)分子的吸附中心的氧气。约 3-4nm 的铁纳米颗粒为 SO(2)分子提供了高度分散的吸附位，从而将吸附容量提高了约 80%。在耗尽样品的表面检测到了 Fe(2)(SO(4))(3)。
