Effect of polymerization degree of polyethylene glycol on microtopography and adsorbability of mesoporous η-Al2O3 fibers
-
摘要: 分别以2种不同聚合度的聚乙二醇（PEG）PEG600和PEG2000为模板导向剂，采用水热法合成η-Al2O3（PEG600）和η-Al2O3（PEG2000）介孔纤维，借助XRD、TEM和N2吸附测试对材料进行表征，研究了PEG聚合度对介孔η-Al2O3纤维性质的影响。通过静态吸附平衡实验考察了介孔η-Al2O3纤维对亚甲基蓝的吸附特性。结果表明：2种模板导向剂均可用于合成介孔η-Al2O3纤维。PEG聚合度对介孔结构、比表面积、孔体积和孔径有较大影响。η-Al2O3（PEG600）的比表面积和孔体积分别为189.899 m2·g-1和0.329 cm3·g-1，分别是η-Al2O3（PEG2000）的1.4倍和1.2倍，平均孔径也比η-Al2O3（PEG2000）的大。2种介孔η-Al2O3纤维对亚甲基蓝的吸附机制均为多分子层吸附。根据BET多层分子吸附方程计算得η-Al2O3（PEG600）和η-Al2O3（PEG2000）对亚甲基蓝的平衡吸附量分别为256.391 3 mg·g-1和204.045 9 mg·g-1。Abstract: The mesoporous η-Al2O3(PEG600)and η-Al2O3(PEG2000)fibers were synthesized by hydrothermal method, using polyethylene glycol (PEG)of different polymerization degree (PEG600 and PEG2000)as the templates, respectively. The prepared samples were characterized by XRD, TEM and N2 adsorption, and the effect of polymerization degree of PEG on the properties of the mesoporous η-Al2O3 fibers was investigated. The absorption property of mesoporous η-Al2O3 fibers toward methylene blue was studied by static equilibrium adsorption experiments. The results show that both of the two templates can be used to synthesize the mesoporous η-Al2O3 fibers. It is found that the polymerization degree of PEG has great effect on mesoporous structure, surface area, pore volume and pore diameter. The surface area and pore volume of η-Al2O3(PEG600)are 189.899 m2·g-1 and 0.329 cm3·g-1, which are 1.4 times and 1.2 times of that of η-Al2O3(PEG2000), respectively. And the average pore diameter of η-Al2O3(PEG600) is also bigger than η-Al2O3(PEG2000). The adsorption mechanism of the two kinds of mesoporous η-Al2O3 fibers is multi molecular layer adsorption. According to the calculation of BET multi molecular layer adsorption equations, the equilibrium adsorption capacities of η-Al2O3(PEG600)and η-Al2O3(PEG2000)towards methylene blue are 256.391 3 mg·g-1 and 204.045 9 mg·g-1, respectively.
-
Keywords:
- PEG /
- polymerization degree /
- mesoporous /
- Al2O3 /
- methylene blue /
- adsorption /
- BET equation
-
-
计量
- 文章访问数: 1024
- HTML全文浏览量: 74
- PDF下载量: 296
下载:
