Mg-Fe-Al复合氧化物的制备及其对二甲酚橙吸附性能研究

Synthesis and Characterization of Mg-Fe-Al Composite Oxide as an Adsorbent for Xylenol Orange Removal

通过化学共沉淀法成功制备了Mg-Fe-Al复合氧化物,运用扫描电子显微镜(SEM)、红外光谱(FT-IR)、X射线衍射仪和比表面积(BET)等手段详细表征了Mg-Fe-Al复合氧化物的结构和形貌,并研究了Mg-Fe-Al复合氧化物对二甲酚橙的吸附行为。实验结果表明,当Mg-Fe-Al的摩尔比为2∶1∶1,合成pH为8,煅烧温度为300℃时,得到的Mg-Fe-Al复合氧化物比表面积达到316.54m^2·g^(-1),对二甲酚橙的最大吸附量达573.86mg·g^(-1)。该吸附过程符合Langmuir吸附方程,属于单分子层吸附。动力学研究表明,该吸附过程符合准二级动力学模型,吸附4h后达到平衡状态。

Mg-Fe-Al composite oxide was prepared by chemical co-precipitation method. The structure andmorphology of Mg-Fe-Al composite oxide were detected by scanning electron microscope （ SEM）, infrared spec-trometer （ FT-IR）, X-Ray Diffractomer and Brunauer-Emmett-Teller （BET）. The adsorption behavior of xylenol orange by Mg-Fe-Al composite oxide was investigated. The results showed that when the molar ratio of Mg-Fe-Al was 2：1 ： 1, synthesis pH = 8, and calcinations temperature was 300 ℃, the maximum adsorption capacity of xy- lenol orange could reach 573.86 mg.g-1. The BET surface area of the Mg-Fe-AI composite material was 316. 54 m 2.g-1 The adsorption process was in line with the Langmuir adsorption isotherm, indicating the monolayer ad- sorption. Kinetic study showed that the adsorption process conformed to the pseudo-second-order kinetic model, and adsorption could reach equilibrium state after 4 h.