皮革胶原基絮凝剂对印染废水的脱色性能

Decolorization property of dyeing effluents with leather collagen-based flocculants

采用碱性水解法从皮革废屑中提取胶原蛋白(HC),以丙烯酰胺(AM)、2-甲基丙烯酰氧乙基三甲基氯化铵(DMC)为改性单体,设计合成了HC-g-PAM、HC-g-PDMC和HC-g-P(DMC+AM)三种胶原基絮凝剂。利用核磁共振仪、扫描电镜以及电位分析仪对接枝产物的结构与性能进行表征,以甲基橙(MO)溶液模拟印染废水作为目标污染物,探究合成参数与絮凝条件对脱色性能的影响。结果表明:胶原基絮凝剂具有疏松、粗糙和多孔化的蜂窝状表面结构,正电荷密度显著增强;絮凝剂最佳投放量为40~60 mg/L,降低pH、减小NaCl浓度及控制废水温度在20℃左右有利于提高絮凝效果,HC-g-P(DMC+AM)的絮凝能力最强,其对MO溶液的脱色率最高可达91.3%。

Collagen(HC)is extracted from leather shavings by alkaline hydrolysis.Three collagen-based floccu⁃lants,namely HC-g-PAM,HC-g-PDMC and HC-g-P(DMC+AM)are designed and synthesized with acryl⁃amide(AM)and 2-methacryloyloxyethyltrimethylammonium chloride(DMC)as modified monomers.The struc⁃ture and properties of the graft products are characterized by nuclear magnetic resonance,scanning electron microscope and potential analyzer.The Methyl Orange(MO)solution is used to simulate the dyeing wastewa⁃ter as the target pollutant to explore the effects of synthesis parameters and flocculation conditions on the de⁃colorization performance.The results show that the collagen-based flocculant has loose,rough and porous honeycomb surface structure,and the positive charge density is significantly increased.The optimal dosage of flocculant is 40-60 mg/L.Reducing pH,reducing NaCl concentration and controlling wastewater temperature at about 20℃are conducive to improving flocculation effect.HC-g-P(DMC+AM)has the strongest flocculation ability,and its decolorization rate of MO solution can reach 91.3%.