合成条件对电解锰渣制备沸石过程中沸石种类和性能的影响

Effects of synthesis conditions on formation process and property of zeolite prepared from electrolytic manganese residue

采用X线衍射(XRD)、扫描电镜(SEM)、傅里叶变换红外光谱(FT-IR)和阳离子交换容量测试(CEC,cation exchange capacity)等手段,研究由电解锰渣合成沸石过程中反应体系初始硅铝物质的量比、反应温度、反应时间等合成条件对沸石种类及其CEC的影响。研究结果表明:随着初始硅铝物质的量比的增加,合成沸石的纯度和CEC均降低,但随着反应温度和反应时间的增加,合成沸石的纯度和CEC则随之增加。基于沸石产品纯度及CEC,制备沸石材料的优化条件为:反应体系初始硅铝物质的量比1.5,反应温度100℃,反应时间1.5h,在此条件下制备的沸石材料主要以A型沸石为主,CEC为3.45mmol/g,产品主要由立方体状晶体组成,结晶度较高,非常适合作为吸附材料使用。

Zeolites were synthesized from electrolytic manganese residue(EMR) via a two-step synthetic procedure. Based on the detailed analyses using X-Ray diffraction(XRD), scanning electron microscope(SEM),Fourier transform-infrared radiation(FT-IR) and cation exchange capacity(CEC) measurement, the major factors influencing the crystalline phase and CEC of zeolite were investigated in the aspects of molar ratio of Si to Al,reaction temperature and reaction time. The results show that the crystalline phase and CEC of zeolite are greatly affected by the molar ratio of Si to Al, reaction temperature and reaction time during the preparation process. The crystalline purity and CEC of zeolite decrease with the increase of initial molar ratio of Si to Al. And the crystalline purity and CEC of zeolite increase with the increase of reaction temperature and reaction time.Meanwhile, the optimal conditions for zeolites synthesized from electrolytic manganese residue are as follows: the initial molar ratio of Si to Al is 1.5, the reaction temperature is 100 ℃ and reaction time is 1.5 h. And the product synthesized under the optimal condition is mainly composed of Na-A zeolite with a CEC of 3.45 mmol/g. It exhibits cubic particles with a chamfered shape, and has high crystallinity, making this material a promising candidate for removal of pollutant diluted in wastewater.