摘要
通过紫色土对Cr(Ⅵ)在不同酸度的静态吸附实验,用Langmuir吸附模型进行拟合得到土壤对Cr(Ⅵ)的吸附曲线和曲线方程,得到酸度影响紫色土对Cr(Ⅵ)的吸附的规律。结果显示:在pH为3.0、5.0和7.0的溶液中,紫色土对Cr(Ⅵ)的吸附随pH降低而降低;不同亚类紫色土吸附能力为石灰性紫色土>中紫色土>酸性紫色土。石灰性紫色土胶体核的碳酸钙含较高,加强了土壤中碳酸盐、氧化物对铬的吸附和固定作用;不同pH环境紫色土对Cr(Ⅵ)吸附的不同,一方面是pH影响了土壤的电势,部分Cr(Ⅵ)转变为Cr(Ⅲ)而沉淀;另一方面是pH影响了土壤中的H+浓度,使胶体团的电位平衡发生破坏,土壤中活性铝和铁溶蚀作用使H+和Cr(Ⅵ)竞争吸附加强,降低对Cr(Ⅵ)的吸附。
Through the purple soil in the static adsorption Cr(Ⅵ) experiment of different pH,Cr(Ⅵ) adsorption curve and curve equation of adsorptionby langmuir adsorption model were got. The results showed that purple soil adsorption of Cr( Ⅵ)decreased with pH decreasing at pH of 3. 0,5. 0 and 7. 0 in the solution; Adsorption capacity of different sub-types of purple soil ordered: calcareous purple soil > purple soil > acid purple soil. Calcareous purple soil colloid nuclear calcium contained more carbonate,and strengthened the adsorption and fixation of carbonates and oxide of chrome in the soil; Different pH of purple soil showed different adsorption on Cr(Ⅵ). The potential pH affected the chromium in soil,part of the Cr(Ⅵ) changed to Cr(Ⅲ) and became the precipitation; the H+concentration was affected by pH in the soil,the balance of potential was damaged by active aluminums and iron in the soil,while the adsorption of Cr(Ⅵ) reduced because the competition adsorption of H+and Cr(Ⅵ).
出处
《环境工程》
CAS
CSCD
北大核心
2015年第S1期857-860,共4页
Environmental Engineering
基金
四川理工学院研究生创新基金资助项目(y2013022)