论文部分内容阅读
将天然累托石(rectorite,REC)与铝交联剂在适宜条件下进行交联反应而制得的铝交联累托石(Al-cross-linked rectorite,ACLREC),由Fourier变换红外光谱和X射线粉末衍射谱显示,经铝交联后REC的基本骨架并没有发生变化,而其(001)面的间距d001由2.37nm提高到2.78nm。在静态条件下,研究了ACLREC对水溶液中Th(Ⅳ)的吸附性能和吸附热力学,考察了pH值、离子强度、吸附时间等因素对吸附效果的影响。结果表明:pH值和离子强度是影响吸附的主要因素,离子交换反应和表面络合反应是ACLREC吸附Th(Ⅳ)的主要机理。在25℃,pH=3.5～4.0,吸附时间为4h,ACLREC用量为0.8g/L,Th(Ⅳ)浓度为0～10mg/L条件下进行吸附,Th(Ⅳ)去除率可达99%以上。热力学分析表明,ACLREC对Th(Ⅳ)的吸附是一个自发的且反应程度较高的过程,符合Freundlich模型。
Al-cross-linked rectorite (ACLREC) prepared by cross-linking natural rectorite (REC) with aluminum cross-linker under suitable conditions was characterized by Fourier transform infrared spectroscopy The results of X-ray powder diffraction (XRD) showed that the basic framework of REC did not change after cross-linking with aluminum, and the spacing d001 of (001) plane increased from 2.37nm to 2.78nm. Under static conditions, the adsorption properties and adsorption thermodynamics of ACLREC on Th (Ⅳ) in aqueous solution were investigated. The effects of pH, ionic strength and adsorption time on the adsorption were investigated. The results showed that pH and ionic strength were the main factors affecting the adsorption. Ion exchange reaction and surface complexation were the main mechanisms of ACLREC adsorption on Th (Ⅳ). The adsorption rate of Th (Ⅳ) was over 99% at 25 ℃, pH = 3.5-4.0, adsorption time 4h, ACLREC dosage 0.8g / L and Th (Ⅳ) concentration 0-10mg / . Thermodynamic analysis showed that adsorption of Th (Ⅳ) by ACLREC was a spontaneous and highly reactive process, which accorded with Freundlich model.