摘要
以粉煤灰为原料,采用“联合改性三步合成法”——超声辅助碱熔微波晶化法联合废旧玻璃/13X晶种/NaH_(2)PO_(4)浸渍三阶段改性合成沸石分子筛(GFS);作为对比,采用传统碱熔水热法合成沸石分子筛(FS);采用“三步合成法”——超声辅助碱熔微波晶化法合成沸石分子筛(WFS)。并采用X射线衍射(XRD)、扫描电镜(SEM)、傅里叶变换红外光谱(FTIR)、能量色散光谱(EDS)、N_(2)吸附-脱附等方法对材料的组成、形貌和结构进行了表征。结果表明,WFS和GFS较FS具有更高的比表面积和发达的介孔、微孔,且沸石分子筛晶型从NaA单晶型转为NaA/NaX双晶型。氨氮吸附实验结果表明,GFS(56.01 mg·g^(-1))较WFS(49.17 mg·g^(-1))和FS(39.75 mg·g^(-1))吸附性能更优,吸附动力学和热力学数据符合二级动力学模型和Langmuir模型,氨氮吸附过程为以离子交换为主的吸附,且为自发放热过程,低温促进氨氮吸附。
The synthesis of zeolite molecular sieves (referred to as GFS) using fly ash as a raw material was carried out in three stages.The method employed for this synthesis was called“combined modification three-step synthe-sis”,which involved ultrasonic-assisted alkali fusion microwave crystallization combined with waste glass/13X seed/Na H_(2)PO_(4) impregnation.To compare the results,traditional alkali fusion hydrothermal synthesis was used to synthe-size zeolite molecular sieves (referred to as FS).In addition,zeolite molecular sieves (referred to as WFS) were syn-thesized using the“three-step synthesis”method of ultrasonic-assisted alkali fusion microwave crystallization.The materials were characterized using various techniques including X-ray diffraction (XRD),scanning electron micros-copy (SEM),Fourier-transform infrared spectroscopy (FTIR),energy-dispersive spectroscopy (EDS),and N_(2) adsorp-tion-desorption analysis to determine their composition,morphology,and structure.The results indicated that WFS and GFS exhibited higher specific surface areas and well-developed mesopores and micropores compared to FS.Additionally,the crystal type of zeolite molecular sieves shifted from Na A single crystal to Na A/Na X twin crystal.Ammonia nitrogen adsorption experiments revealed that GFS (56.01 mg·g^(-1)) showed better adsorption performance than WFS (49.17 mg·g^(-1)) and FS (39.75 mg·g^(-1)).The adsorption of ammonia nitrogen follows the second-order kinet-ics model and the Langmuir model,as indicated by kinetic and thermodynamic data.This process primarily relies on ion exchange and is both spontaneous and exothermic.Lower temperatures enhance the adsorption of ammonia nitrogen.
作者
蔡元韬
王坤
郭欣辰
卢莹怡
张慧琦
韩熠垚
谢云龙
叶向荣
CAI Yuantao;WANG Kun;GUO Xinchen;LU Yingyi;ZHANG Huiqi;HAN Yiyao;XIE Yunlong;YE Xiangrong(Xingzhi College,College of Chemistry and Materials Science,Zhejiang Normal University,Jinhua,Zhejiang 321004,China;Zhejiang Institute of Photoelectronics,Jinhua,Zhejiang 321004,China)
出处
《无机化学学报》
SCIE
CSCD
北大核心
2024年第1期124-134,共11页
Chinese Journal of Inorganic Chemistry
基金
浙江省“尖兵”研发攻关计划项目(No.2022C01030)
金华市重点科学技术研究计划项目(No.2021-1-020)资助。
关键词
联合改性三步合成法
粉煤灰
NaA/NaX双晶型
吸附氨氮
combined modification three-step synthesis
fly ash
NaA/NaX double crystal zeolite
ammonia nitrogen adsorption
