硫酸改性麻黄废渣对Cu^(2+)的吸附研究  

Study on the adsorption of Cu^(2+) by chemically modified ephedra waste

作　　者：时洋[1] 马春芳[1] 朱彦姝[2] 冯宁川[2] 

机构地区：[1]宁夏医科大学药学院,宁夏银川750004 [2]宁夏医科大学基础医学院,宁夏银川750004

出　　处：《环境污染与防治》2014年第8期24-28,共5页Environmental Pollution & Control

基　　金：国家自然科学基金资助项目(No.21266026)

摘　　要：用硫酸对麻黄废渣进行化学改性,制备改性麻黄废渣,并用于模拟废水中Cu2+的吸附。通过扫描电子显微镜、傅里叶红外光谱仪和官能团滴定等方法对改性麻黄废渣进行表征;采用静态吸附实验,考察了溶液pH、吸附剂用量、吸附时间等对吸附效果的影响。结果表明,麻黄废渣改性后,酸性基团数量明显增加,羟基和羧基也均有大幅度的增加,表面比改性前变得粗糙和疏松多孔,表面积增大,更有利于对Cu2+的吸附。室温(25℃)下改性麻黄废渣吸附Cu2+的较佳条件为:溶液pH 5.0、吸附时间60min、改性麻黄废渣用量4g/L。改性麻黄废渣对Cu2+的吸附可以用准二级动力学方程描述,Cu2+的饱和吸附量为2.20mmol/g,与改性前(1.49mmol/g)相比有明显提高。改性麻黄废渣吸附—解吸附循环使用5次中,Cu2+的平均解吸率达到83%左右,麻黄废渣平均再生率达到94%以上,经5次循环使用,Cu2+吸附率仍可达到99.46%,说明改性麻黄废渣具有良好的重复利用性能。The ephedra waste was chemically modified by sulfuric acid to adsorb Cu2＋ ions from simulated wastewater. The obtained modified ephedra waste was characterized by Scanning electron microscope （SEM）, Fourier infrared spectrometer （FTIR） and functional group titration method. The static adsorption experiments were carried out to investigate the effect of solution pH, adsorbent dosage and contact time on Cu2＋ removal efficiency. Results showed that the number of acidic group increased obviously,so as the carboxyl and hydroxyl groups. The surface of modified ephedra waste was coarse, poriferous and of lax structure, the superficial area was greatly increased, which was benefited for the Cu2＋ adsorption. The optimum conditions for Cuz＋ adsorption on modified ephedra waste at room temperature were solution pH of 5.0, contact time of 60min,adsorbent dosage of 4 g/L. The Cuz＋ adsorption on modified ephedra waste could be well fitted by pseudo-second order kinetics equation. The maximum Cu2＋ adsorption capacity of modifiedadsorbent was 2.20 mmol/g,more than that of unmodified adsorbent （1.49 mmol/g）. During the 5 cycles of adsorption-desorption process,the average Cu2＋ desorption rate was 83%, the average regeneration rate was above 94% ,Cu2＋ of recycled adsorbent could reach to 99.46%,indicating the perfect recycle performance of modified ephedra waste.

关 键 词：麻黄废渣 化学改性 CU2+ 吸附 

分 类 号：X703[环境科学与工程—环境工程]