基于响应曲面法的磁性离子交换树脂去除甲基橙和刚果红的优化

选取树脂用量、溶液初始pH值、吸附质浓度和吸附时间四个因素，用Box-Behnken响应曲面法分别建立了甲基橙和刚果红在磁性离子交换(MIEX)树脂上吸附的二次多项式回归模型，使用方差及显著性分析证明了回归方程的可靠性。优化了MIEX树脂去除甲基橙和刚果红的工艺参数，探究了最佳工艺条件下MIEX树脂对甲基橙(刚果红)的去除效果。使用NaCl再生饱和吸附后的MIEX树脂，用扫描电镜对吸附前后的树脂进行表征。结果表明，在最优工艺条件下，MIEX树脂对甲基橙和刚果红的去除率最高可达99.12%和98.29%。溶液初始pH值和树脂用量之间的交互作用对MIEX树脂去除甲基橙和刚果红有显著影响。NaCl溶液对MIEX树脂的再生效果显著。

Removal optimization of methyl orange and Congo red adsorbed on MIEX resin using response surface methodology

Four factors including resin dosage, solution pH, methyl orange or Congo red concentration and adsorption time were selected to investigate the effects on the removal of methyl orange or Congo red adsorbed on MIEX resin using Box-Behnken response surface methods. According to the experimental results, the quadratic polynomial regression model was established to predict the removal of methyl orange or Congo red. Variance and significance were used to test the reliability of the regression equation. Based on the regression model, the operation parameters of the removal of methyl orange (Congo red) adsorbed on MIEX resin were optimized and the optimal conditions were obtained. Under the optimal conditions, the removal efficiency of methyl orange and Congo red on MIEX resin were 99.12% and 98.29%, respectively. The interaction between solution pH and resin dosage had a significant effect on the removal efficiency of methyl orange and Congo red. The saturated resin adsorbed methyl orange or Congo red were regenerated using NaCl solution, and the surface morphology of MIEX resin were characterized by field scanning electron microscopy. The results showed that the spent resin can be regenerated well with NaCl solution.