天然斜发沸石水热转化Na-P沸石及其吸附镉的性能研究

Hydrothermal Transformation of Natural Clinoptilolite Zeolite to Zeolite Na-P and Its Adsorption Property for Cd ion

以河北承德围场地区天然沸石为原料,对其进行水热改性制备Na-P沸石。采用X射线衍射仪、X射线光电子能谱仪、气体吸附仪、扫描电镜和能谱分析仪等对材料进行表征分析,采用Cd^(2+)离子评价材料的重金属离子去除性能。研究碱处理浓度、水热温度和时间对天然沸石结构的影响规律,着重研究所制备Na-P沸石的组成结构特征及重金属离子去除性能。结果表明:在NaOH浓度3 mol/L、水热温度100℃、水热时间12 h的条件下,斜发沸石可转化为纯度较高的Na-P沸石。所得材料对Cd^(2+)的吸附容量为35.7 mg/g,较天然沸石提升7倍。Na-P沸石性能的提升主要归功于其较低的硅铝比和较高的表面Na^(+)含量。

Natural clinoptilolite zeolites from Weichang region,Chengde city,Hebei province were transformed to a zeolite Na-P using hydrothermal method.The as-prepared materials were characterized and analyzed by X-ray diffraction,X-ray photoelectron spectroscopy,gas adsorption instrument,scanning electron microscope and energy spectrum analyzer.The heavy metal ions removal performance was evaluated by Cd^(2+) ion.The effects of alkali treatment concentration,hydrothermal temperature and time on the structure of natural zeolite were investigated.The composition,structural characteristics and heavy metal ion removal performance of the prepared zeolite Na-P materials were further studied.The results showed that clinoptilolite could be transform to zeolite Na-P with 3 mol/L NaOH solution under the conditions of hydrothermal temperature of 100℃and hydrothermal time of 12 h.The adsorption capacity of the obtained material for Cd^(2+) was 35.7 mg/g,which was 7 times higher than that of natural zeolite.Its excellent performance was mainly due to low silicon/aluminum ratio and relative higher exchangeable Na ion content.