粉煤灰合成沸石对亚甲基蓝的吸附热力学和动力学研究

为了扩大粉煤灰的再利用领域,本文采用水热合成法制备了沸石;同时以其作为吸附材料,用于吸附染料亚甲基蓝的研究,考察了溶液初始p H值、吸附时间等因素对吸附效果的影响,并进一步拟合吸附动力学和吸附等温线,初步分析了吸附机理。结果表明：粉煤灰合成的沸石对亚甲基蓝具有较好的吸附能力;p H值是影响吸附效果的一个重要参数;沸石对亚甲基蓝的吸附过程在90 min达到吸附平衡;沸石对亚甲基蓝的吸附过程符合二级反应动力学和Langmuir吸附等温方程,说明该吸附过程是以化学吸附为主且典型的单分子层吸附。

Adsorption of Methylene Blue by Synthesized Zeolite from Coal Fly Ash

By using coal fly ash as main material,the hydrothermal synthesis method was adopted to prepare zeolite to expand coal fly ash＇s application area in this paper. At the same time,the new adsorbent of zeolite was used for removing methylene blue（ MB）. And the effects of performance parameters such as p H,adsorption time etc. were investigated. The adsorption kinetics and adsorption isotherms were simulated to supply theoretic evidence for application. And the mechanism was preliminarily analyzed. The results showed that synthesized zeolite from coal fly ash had good performance of MB adsorption. The p H is one of the most important parameters for removing MB in solution. The removal rate increased slowly with the increasing of adsorbing time and when it reached 90 min,the removal rate of MB tended to be equilibrium. The adsorption kinetics was described by pseudo-second rate model and the adsorption equilibrium was accorded with Langmuir isotherm adsorption equation,that shows adsorption of zeolite for MB could be chemical adsorption and typical single-molecule layer.