谷氨酸—木质素吸附剂的制备及对Pb^(2+)的吸附性能  

Synthesis of Glutamic Acid-Lignin Adsorbent and Its Adsorptivity to Pb^(2+)

作　　者：马英梅[1] 方桂珍[1] 张锐[1] 李宏振[1] 马艳丽[1] 

机构地区：[1]生物质材料科学与技术教育部重点实验室(东北林业大学),哈尔滨150040

出　　处：《东北林业大学学报》2009年第10期88-90,共3页Journal of Northeast Forestry University

基　　金：黑龙江省"十一五"科技支撑项目(GB06B501-3)

摘　　要：以碱木质素、谷氨酸钠及甲醛为原料,依据Mannich反应制备谷氨酸—木质素吸附剂(GA-L)。采用FT-IR和凯氏定氮表征其化学结构,并分析了吸附时间、吸附剂用量、pH值及反应温度对Pb2+吸附性能的影响。研究结果表明,谷氨酸已接枝到木质素上,产物氮质量分数为2.62%;GA-L在3h达到饱和状态,最佳吸附剂用量为0.2g/L;对酸性介质中的Pb2+具有良好的吸附性能,吸附容量随初始重金属离子质量浓度和温度的增加而增大;引入的胺基和羧基明显提高了木质素的络合能力,GA-L对Pb2+的吸附容量可达87.28mg/g,与未改性木质素(35.07mg/g)相比提高了148.87%。25℃时初始Pb2+质量浓度在20～200mg/L范围内,吸附规律符合Langmuir平衡模型,吸附机理以单分子层化学吸附为主。Glutamic acid-lignin adsorbent （GA-L） was synthesized from alkali lignin modified with sodium glutamate and formaldehyde via Mannich reaction. Chemical changes were analyzed using FT-IR and Kjeldahl, and the effects of adsorption time, usage, pH value, and temperature on the adsorption properties of GA-L to Pb^2＋ were investigated. Results indicated that glutamic acid had been grafted into lignin, and the nitrogen content of the resulting product was 2.62 percent. GA-L reached saturation within 3 hours, and the optimum usage was 0.2 g/L. The material exhibited desirable adsorption property to Pb^2＋ existed in acidic medium, and the adsorption capacity enhanced as beth initial ionic concentration and temperature increasing. Owing to the introduction of amidocyanogen and carboxyl, the adsorption capacity of GA-L to Pb^2＋ reinforced significantly, and the maximum reached 87.28 mg/g, increasing by 148.87 percent compared with the unmodified GA-L （35.07 mg/g）. The adsorption data followed Langmuir model within the concentrations of Pb^2＋ ranging from 20 to 200 mg/L at 25 degrees C, and the chemieal monolaver adsorption was dominant.

关 键 词：碱木质素 谷氨酸 MANNICH反应 吸附 PB2+ 

分 类 号：X793[环境科学与工程—环境工程]