State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, PR China.
J Colloid Interface Sci. 2013 Aug 15;404:42-8. doi: 10.1016/j.jcis.2013.04.018. Epub 2013 Apr 24.
The present study offers an economic one-pot synthesis of Al-containing ordered mesoporous silica MCM-41 from the coal fly ash. The samples were characterized by small-angle XRD, N2 adsorption, TEM, mapping, (27)Al MAS NMR, EDX, and NH3-TPD. The effects of pH values to the final mesostructures have also been investigated. The results show that the material prepared at the pH value of 10 displays the largest pore volume of 0.98 cm(3)/g, the highest BET surface area of 1020 m(2)/g, and the lowest Si/Al molar ratio of 2. Using this material as adsorbent for phosphates, the adsorption capacity reaches 64.2mg/g at 298 K, which is much higher than that of large pore mesoporous silica SBA-15 (53.5mg/g), diatomite (62.7 mg/g), and MCM-41 (31.1 mg/g). In addition, the thermodynamics and kinetics for the phosphate adsorption were also investigated. Our present study shows an economic way to treat phosphates using the industrial solid waste of coal fly ash.
本研究提供了一种从粉煤灰中经济地合成含铝有序介孔硅 MCM-41 的方法。采用小角 XRD、N2 吸附、TEM、mapping、(27)Al MAS NMR、EDX 和 NH3-TPD 对样品进行了表征。还考察了 pH 值对最终介孔结构的影响。结果表明，在 pH 值为 10 的条件下制备的材料具有最大的孔体积（0.98 cm(3)/g）、最高的 BET 比表面积（1020 m(2)/g）和最低的 Si/Al 摩尔比（2）。将这种材料用作磷酸盐的吸附剂，在 298 K 时的吸附容量达到 64.2mg/g，远高于大孔介孔硅 SBA-15（53.5mg/g）、硅藻土（62.7 mg/g）和 MCM-41（31.1 mg/g）。此外，还研究了磷酸盐吸附的热力学和动力学。本研究为利用粉煤灰这种工业固体废物处理磷酸盐提供了一种经济的方法。
