钛柱撑蒙脱石颗粒的制备及其对镉离子的吸附

为脱除废水中镉离子,以钠基蒙脱石作基质材料,钛酸四丁酯为钛源,制备了钛柱撑蒙脱石。然后将聚乙烯醇、海藻酸钠、钛柱撑蒙脱石以一定的质量比制备钛柱撑蒙脱石颗粒,并进行颗粒的散失实验及镉离子的吸附实验,同时进行吸附等温线及吸附动力学研究。结果表明,Ti-MMT具有较大的晶面间距(d₀₀₁=3.43 nm)。当m(聚乙烯醇)∶m(海藻酸钠)∶m(钛柱撑蒙脱石)=0.6∶1.0∶20.0时,投加0.25 g颗粒于pH值=6的100 mg/L的镉离子废水中,在40℃下,吸附120 min,颗粒对Cd²⁺的吸附量达到7.89 mg/g,去除率达到98.63%,且颗粒对Cd²⁺的吸附符合Langmuir等温线模型,吸附动力学符合拟二级动力学方程。

Preparation of titanium pillared montmorillonite particles and its adsorption of cadmium ions

In order to remove cadmium ions from wastewater,sodium montmorillonite was used as the matrix material,and tetrabutyl titanate was used as the titanium source to prepare titanium pillared montmorillonite. Then,polyvinyl alcohol,sodium alginate and titanium pillared montmorillonite were prepared to prepare titanium pillared montmorillonite particles with a certain mass ratio,and cadmium ion adsorption experiments and particle loss experiments were carried out. The results show that titanium pillared montmorillonite had a large interplanar spacing d 001 of 3.43 nm. When polyvinyl alcohol:sodium alginate:titanium pillared montmorillonite was 0.6∶1.0∶20.0,0.25 g of granules were added to 100 mg/L of Cd^ 2+ wastewater. The adsorption capacity of Cd 2+ by titanium pillared montmorillonite reached 7.89 mg/g and the removal rate reached 98.63% after 120 min adsorption at 40 ℃ with ph of 6. The adsorption of Cd^ 2+ by the particles fitted well to the Langmuir isotherm model and the adsorption kinetics followed the pseudo-second-order model.