木质素胺的合成及絮凝脱色作用

Flocculated Decolorization Properties and Synthesis of Ligninamine

以造纸黑液中提取的木质素为原料,通过Mannich反应将木质素胺化改性合成木质素胺;以氮元素含量来确定木质素的改性率。通过黏度和表面张力的测定对木质素胺的物理性能进行分析,并用FT-IR、TG-DSC、UV等对木质素和木质素胺的结构进行了探讨。另外对样品进行了絮凝脱色试验,研究了染料初始浓度、木质素用量对品红脱色效果的影响。结果表明,与木质素相比,木质素胺的黏度增大,表面张力降低,表面活性增强,相对分子质量增加,分解温度提高,絮凝脱色效果也明显优于木质素;当品红初始浓度为12mg/L,木质素胺浓度为0.5g/L,脱色时间100min时,脱色率可达93%以上。

Cationic lignin amines were obtained by the Mannich reaction between hexanediamine and lignin from black liquor. The amination modification effect of the lignins was determined by nitrogen content. Physical properties of ligninamine were analyzed by measuring viscosity and surface tension. The structure of lignin and ligninamine was discussed through FT-IR, thermal analysis technique （TG-DSC） and UV. The test of flocculated decolorization for the modified lignin samples was carried out, and initial dye concentration and effect of lignin content on magenta decolorization were studied. The results show that ligninamine has the larger viscosity, lower surface tension, greater molecular weight, higher decomposition temperature and better surface activity than the lignin. The flocculation capacity and decolorization efficiency of ligninamine is obviously better than those of lignin. The decolorization rate is above 93% under the optimal conditions of initial concentration of magenta 12mg/L, ligninamine concentration 0.5g/L,adsorption time 100 min.