煤基NaA分子筛材料的合成及其对Cd2+的吸附  

Synthesis of coal-based NaA molecular sieve material and Cd2+adsorption

作　　者：刘甜 郭军康 张蕾 王孜昊 喻先伟 王家圆 毕江涛[2] LIU Tian;GUO Junkang;ZHANG Lei;WANG Zihao;YU Xianwei;WANG Jiayuan;BI Jiangtao(Environmental Science and Engineering,Shaanxi University of Science and Technology,Xi′an 710021,China;School of Ecological Environment,Ningxia University,Yinchuan 750021,China)

机构地区：[1]陕西科技大学环境科学与工程学院,西安710021 [2]宁夏大学生态环境学院,银川750021

出　　处：《农业环境科学学报》2023年第2期443-450,共8页Journal of Agro-Environment Science

基　　金：国家自然科学基金项目(41977274);陕西省科技创新团队项目(2022TD-09);陕西省重点产业链项目(2022ZDLNY02-02)。

摘　　要：为实现废弃物资源化利用,采用煤矸石为原料制备分子筛环境修复材料。通过对煤矸石(CG)的硅铝比进行调节,利用煅烧-水热晶化法分别在500℃和750℃下成功合成了NaA-500和NaA-750两种煤基NaA分子筛材料。进一步采用X射线衍射(XRD)、扫描电镜(SEM)等表征方法探讨了分子筛的结构特征和表观形貌,并对吸附过程进行吸附动力学和等温吸附线的研究分析,以深入探究其对Cd^(2+)的吸附特性。结果表明:相比煤矸石,NaA-750和NaA-500对Cd^(2+)的最高吸附量分别为392.9 mg·g^(-1)和208.9 mg·g^(-1),分别是煤矸石的4.5倍和2.4倍,且NaA-750和NaA-500对Cd^(2+)的吸附过程遵循准二级动力学规律。吸附等温线结果显示,NaA-500和NaA-750对Cd^(2+)的吸附符合Langmuir等温吸附模型。综上所述,以煤矸石为原料制备的NaA型分子筛对Cd^(2+)的吸附能力明显提升且具有较高的吸附容量,对去除废水中Cd^(2+)具有潜在应用价值。To realize waste resource utilization,coal gangue has been applied as a raw material to produce molecular sieve environmental remediation materials.NaA-500 and NaA-750 have been successfully synthesized by adjusting the silica-alumina ratio of coal gangue through calcination-hydrothermal crystallization approach at two temperature of 500℃and 750℃,respectively.The structural characteristics and apparent morphology of the molecular sieves were further investigated using X-ray diffraction(XRD)and scanning electron microscope(SEM)characterization techniques.The adsorption kinetics and isotherm models were employed to evaluate the Cd^(2+)adsorption behavior on the synthesized materials.The maximum adsorption capacity of both coal-based molecular sieve materials towards Cd^(2+)increased significantly,compared with that of coal gangue.The maximum Cd^(2+)adsorption capacity of NaA-750 was 392.9 mg·g^(-1),and that of NaA-500 was 208.9 mg·g^(-1),which were 4.5 times and 2.4 times that of coal gangue.The NaA-500 and NaA-750 experimental results showed that the pseudo-second-order models and Langmuir isotherm model were more suitable for fitting the experimental data,respectively.In conclusion,the adsorption performance of NaA molecular sieve which prepared from coal gangue to Cd^(2+)is significantly improved and with high adsorption capacity,indicating that NaA molecular sieve has potential application value for the removal of Cd^(2+)from wastewater.

关 键 词：煤矸石 分子筛 Cd2+ 吸附 固废资源化 

分 类 号：TQ424.25[化学工程] X703[环境科学与工程—环境工程]