柑橘渣的阳离子化改性及其对刚果红的吸附性能

摘要

To improve the adsorption performance of citrus pulp(CP),using cationic(3-chloro-2-hydroxypropyl)trimethylammonium chloride(CHPTAC),as monomer,CHPTAC-modified citrus pulps(CP-CHPTAC)were prepared under alkaline condition.The adsorption behavior to the anionic dye Congo red was investigated.The effects of the amount of CHPTAC,initial concentration of Congo red,adsorption time and pH value on the adsorption were tested.The isothermal adsorption model and adsorption kinetics were also analyzed.The results showed that with the increase of CHPTAC dosage,the equilibrium adsorption capacity of Congo red increased.At a pH of 4.6 and adsorption temperature of 25 ℃,the decolorization rate of Congo red reached 94％by CP-CHPTAC with graft ratio of 20.6％,and the adsorption process conform to the Langmuir isotherm model and pseudo-second-order kinetic model.The CP-CHPTAC suggested a good reusability and stability as it exhibited remarkable adsorption efficiency on Congo red after 6 times regeneration cycles.%为提高柑橘渣(CP)的吸附性能,以(3-氯-2-羟丙基)三甲基氯化铵(CHPTAC)为阳离子单体,在碱性条件下对柑橘渣进行改性,制备了阳离子改性柑橘渣(CP-CHPTAC).研究了该吸附剂对阴离子染料刚果红的吸附行为,考察了CHPTAC用量、刚果红溶液初始浓度、吸附时间和pH值对吸附效果的影响,并对等温吸附模型和吸附动力学进行分析.结果表明,随着CHPTAC接枝率的增大,刚果红平衡吸附量提高; 在pH值4.6,吸附温度25℃条件下,接枝率为20.6％的CP-CHPTAC对刚果红的脱色率达94％以上,吸附过程符合Langmuir等温吸附模型及伪二级动力学模型.CP-CHPTAC经过6次再生测试后,对刚果红仍有良好的吸附效果,显示出优异的重复使用性和稳定性.