高铝粉煤灰基NaP1型沸石/水合金属氧化物的制备及其对亚甲基蓝的吸附

Preparation of NaP1 Zeolite/Hydrated Metal Oxides Based on High Alumina Coal Fly Ash and Its Adsorption of Methylene Blue

以高铝粉煤灰为原料,通过水热法制备沸石,然后在室温下,采用沉淀法在其表面负载水合金属氧化物,分别得到了沸石/水合氧化锆和沸石/水合氧化铁。通过XRD、SEM、BET对吸附剂进行表征,并对沸石及负载型沸石吸附亚甲基蓝的吸附动力学和吸附等温线进行研究。结果表明,粉煤灰基沸石为NaP1型,比表面积为50. 88 m^2/g,平均孔径为8. 01 nm。沸石及负载型沸石吸附亚甲基蓝过程均符合准二级动力学模型,以化学吸附为速率控制步骤,吸附等温线均更符合Langmuir方程。其中,沸石/水合氧化铁的理论饱和吸附量高达185 mg/g,并且在无需调节溶液的pH值条件下,再生后的样品对亚甲基蓝的去除率仍然达到90%以上。因此,高铝粉煤灰基沸石原位负载水合金属氧化物材料是一种新型高效、绿色环保的吸附剂。

Zeolite/hydrated zirconia and zeolite/hydrated iron oxide were obtained respectively by the process in which zeolite was prepared from high alumina coal fly ash by hydrothermal method,and then at room temperature,hydrated metal oxides were loaded on the surface by precipitation method.These adsorbents were characterized by XRD,SEM and BET,and the adsorption kinetics and adsorption isotherm of zeolite and loaded zeolite for methylene blue were studied.The results show that the coal fly ash-based zeolite is identified as NaP1,with the specific surface area of 50.88 m^2/g and the average pore diameter of 8.01 nm.The adsorption process for methylene blue is well fitted to pseudo-second-order model and chemical adsorption is taken as the rate control step.The adsorption isotherm fits the Langmuir model.For zeolite/hydrated ferric oxide,its calculated saturated adsorption capacity reaches 185 mg/g,and without adjusting pH value of the solution,the removal rate of methylene blue by its regenerated sample is still above 90%.Therefore,high alumina coal fly ash-based zeolite loaded with hydrated metal oxides is a new kind of adsorbent with high efficiency.