酸改性甘蔗渣对电镀废水中Cr(Ⅵ)的吸附特性研究

Adsorption characteristics of Cr(Ⅵ)in electroplating wastewater by acid modified bagasse

研究了草酸和磷酸改性甘蔗渣对模拟废水中Cr(Ⅵ)的吸附效果,并通过扫描电子显微镜、傅里叶变换红外光谱仪和比表面积测试等方法对2种改性甘蔗渣进行表征。表征结果显示,3种吸附剂的比表面积表现为磷酸改性甘蔗渣>草酸改性甘蔗渣>普通甘蔗渣;2种酸改性甘蔗渣较普通甘蔗渣的含氧官能团种类和数量大幅度增加,吸附能力提高。吸附实验结果表明,3种吸附剂吸附量表现为草酸改性甘蔗渣>磷酸改性甘蔗渣>普通甘蔗渣。吸附热力学及动力学研究显示,Langmuir等温吸附模型能更好地描述吸附过程,吸附过程遵循准二级动力学方程。

The effect of oxalic acid and phosphate modified bagasse on the adsorption of Cr(Ⅵ)in simulated wastewater was studied.Two bagasses were characterized by SEM,FT-IR,and BET.The characterization results showed that the specific surface area of phosphate modified bagasse>oxalic acid modified bagasse>ordinary bagasse.The oxygen-containing functional groups type and number of two kinds of modified bagasse than that of ordinary bagasse,which greatly increased adsorption capacity.The results shown that the adsorption capacity was represented by oxalic acid modified bagasse-based>phosphate-modified bagasse-based>common bagasse.The results of adsorption thermodynamics and kinetics shown that the Langmuir isotherm adsorption model can better reflect the adsorption process and the adsorption process followed the pseudo-second order kinetic equation.