溴代十六烷基吡啶改性沸石对水中Cr(Ⅵ)的吸附去除作用

Adsorption removal of Cr(Ⅵ) in aqueous solution using modified clinoptilolite

以溴代十六烷基吡啶改性沸石为吸附分离材料,研究了其对水中Cr(Ⅵ)去除率的影响和吸附等温线以及吸附机理.结果表明,在改性沸石粒度为0.25～0.38mm、用量30g.L-1、溶液pH=6、25℃的条件下振荡吸附30min,水中Cr(Ⅵ)的去除率达到93%以上.改性沸石对水中Cr(VI)的吸附符合Langmuir等温吸附线,对Cr(Ⅵ)的饱和吸附量每100g改性沸石达到36.78mg.X射线衍射分析表明,改性沸石结构中吸附了溴代十六烷基吡啶分子基团C21H38NBr,红外光谱分析证明正是这一基团造成了改性沸石对水中Cr(Ⅵ)的吸附去除.

The adsoption removal of Cr(Ⅵ) in aqueous solution and the adsorption isotherm and adsoption mechanism were studied with C21H38NBr modified clinoptilolite used as a water treatment material.The result showed that after 30 min adsorption treatment at 25 ℃,the removal rate of Cr(Ⅵ) in aqueous solution surpassed 93% under treatment conditions of modified clinoptilolite particle size of 0.25-0.38 mm,clinoptilolite concentration of 30 g·L-1 at the initial pH=6.The adsorption of Cr(Ⅵ) to modified clinoptilolite could be expressed with Langmiur adsorption isotherm.The saturated adsorption amount of Cr(Ⅵ) reached 36.78 mg per 100 g with modified clinoptilolite.By comparing the XRD spectra of the modified clinoptilolite and the unmodified clinoptilolite,C21H38NBr could be found in the modified clinoptilolite.IR analysis indicated that the adsorption removal of Cr(Ⅵ) by modified clinoptilolite was the function of C21H38NBr in the modified clinoptilolite.