2种介孔硅藻的制备及其对废水中Cd^(2+)的吸附

Preparation of two kinds of mesoporous diatomite and their adsorption for Cd^(2+) in wastewater

以硅藻土为天然硅源,CTAB为模板剂制得介孔硅藻(DM)和磁性介孔硅藻(MDM)。采用SEM、FTIR和STA对制备的产品进行了表征,并以Cd^(2+)为目标污染物,研究了2种吸附材料对Cd^(2+)的吸附性能。结果表明,当初始Cd^(2+)质量浓度为10 mg/L,温度为25℃,pH=6,DM和MDM投加量为3 g/L,吸附时间为30 min时,DM和MDM对Cd^(2+)的去除率分别为85.67%和98.75%,且均可再生使用5次。DM和MDM对Cd^(2+)的吸附分别符合Freundlich和Langmuir等温吸附模型,吸附过程均符合准二级动力学方程。

Using diatomite as natural silicon source,and CTAB as template,mesoporous diatomite(DM)and mag-netic mesoporous diatomite(MDM)have been prepared,and the prepared products characterized by means of SEM FTIR and STA.Taking Cd2+as target pollutant,the adsorption capabilities of two kinds of adsorbing materials for Cd2+have been investigated.The results show that when the initial Cd2+mass concentration is 10 mg/L,temperature 25℃,pH 6,dosages of DM and MDM are both 3 g/L,and reaction time lasts for 30 min,the removing rates of DM and MDM for Cd2+are 85.67%and 98.75%,respectively.Both of them have good adsorption effect on Cd2+and can be reused 5 times.The behavior of DM and MDM adsorption for Cd2+complies with Freundlich and Langmuir isotherm models,respectively,and both of the adsorption processes complies with pseudo-second-order kinetics equation.