环氧氯丙烷改性橙皮对偶氮染料的吸附研究

A Study on the Adsorption of Azo Dyes with Epichlorohydrin Modified Flavedo

以环氧氯丙烷为改性剂,对橙皮进行改性处理,利用FTIR和SEM对改性橙皮的官能团和表面形貌进行了分析,并利用改性橙皮对模拟染料废水中的亚甲基蓝和中性红进行吸附,探讨了溶液初始pH值、吸附剂用量、吸附时间、溶液初始质量浓度对亚甲基蓝和中性红的吸附影响。研究结果表明,室温下,pH为7,投加量为2 g/L,吸附时间为540 min,染料初始浓度为1 200 mg/L的条件下,改性橙皮对中性红和亚甲基蓝的最大吸附量分别为485.44 mg/g和561.79 mg/g,未改性橙皮对中性红和亚甲基蓝的最大吸附量分别为201.94 mg/g和254.63 mg/g;FTIR谱图的相关吸收峰的变化说明橙皮纤维素发生了醚化反应,SEM分析表明了橙皮的表面发生了显著变化;动力学研究表明,改性橙皮对亚甲基蓝和中性红的吸附均符合二级动力学方程,吸附作用遵循Langmuir等温吸附方程。

The flavedo was modified with epichlorohydrin, and characterized by SEM and FTIR. The adsorption of methylene blue and netural red by modified flavedo was studied,The effects of pH value, initial concentration, contact time and dosage on the adsorption performances for two azo dyes were investigated. The results indicate that in the conditions of pH of 7, the initial concentration of 1 200 mg/ L, the dosage of 2 g/L, the contact time for 540 min, the absorption capacities of modified flavedo for NR and MB were 485.44 mg/g and 561.79 mg/g at room temperature, while that of unmodified flavedo were 201.94 mg/g, 254.63 mg/g respectively; FT-IR demonstrated that the etherification happened on the cellulose; SEM analysis indicated that the surface of flavedo changed a lot after modification; The ad- sorption process of the mentioned dyes on modified flavedo obeyed pseudo-second-order kinetic equation and complied with Langmuir isotherm equation.