响应面法优化氧化石墨烯对Cr(Ⅵ)的吸附

Optimization of Adsorption of Cr(Ⅵ) on Graphene Oxide by Response Surface Method

为了提高氧化石墨烯(GO)处理含铬废水的处理效果,采用响应曲面法对氧化石墨烯(GO)吸附Cr(Ⅵ)进行优化。以氧化石墨烯(GO)浓度、吸附时间和Cr(Ⅵ)初始浓度为自变量,以Cr(Ⅵ)去除率为响应值,进行三因素三水平的响应面实验,通过建立的二次多项式数学模型,研究各因素对响应值的影响,通过3D Surface模型分析三因素对响应值的交互作用。结果表明,GO浓度为2.6 g/L、Cr(Ⅵ)初始浓度5 mg/L、吸附时间为90 min,Cr(Ⅵ)去除率为60%左右,与预测值和实测值接近,氧化石墨烯(GO)浓度和吸附时间交互作用对Cr(Ⅵ)去除效果影响较显著。

To improve the treatment effect of chromium wastewater with graphene oxide（GO）, the adsorption process with graphene oxide was optimized by response surface method（RSM）. The concentration of GO, adsorption time and the initial concentration of Cr（Ⅵ） were selected as response factors, meanwhile, the removal rate of Cr（Ⅵ） was used as response value, the three-factor three-level response surface experiment design was carried out. A quadratic model about the removal rate associated with the above factors was derived,and the effect of each factor on response value was discussed with RSM. The interaction of three factors on response value was analyzed by 3 D surface model. The optimum adsorption conditions of GO were as follow： the concentration of GO 2.6 g/L, the adsorption time 90 min and the initial concentration of Cr（Ⅵ） 5 mg/L. Under above conditions, the removal rate was about 60%. Predicted values and measured values were close. The interaction between the concentration of GO and the adsorption time had significant effect for the removal of Cr（Ⅵ）.