杉木树皮吸附重金属离子性能和动力学研究  

Adsorption Performance of Heavy Metal Ions by Fir Bark and Its Kinetic

作　　者：苏文鹏[1] 杨益琴[1] 蒋玲玉[1] 周浩[1] 周永红[2] 

机构地区：[1]南京林业大学江苏省制浆造纸科学与技术重点实验室,江苏南京210037 [2]中国林业科学研究院林产化学工业研究所,江苏南京210042

出　　处：《林产化学与工业》2014年第4期9-15,共7页Chemistry and Industry of Forest Products

基　　金：'十二五'国家科技支撑计划资助项目(2012BAD32B05)

摘　　要：通过间歇吸附的方法研究了杉木树皮粉对水溶液中Cu2＋、Cd2＋和Pb2＋重金属离子的吸附性能,研究了树皮粉粒径大小、重金属离子水溶液的pH值、吸附时间和溶液的初始浓度对杉木树皮吸附重金属离子吸附量的影响,并对吸附过程的等温吸附方程和吸附动力学模型进行了模拟拟合.结果表明：杉木树皮粉可以有效地吸附水溶液中的重金属离子,树皮粒径大小以250～830 μm为宜,吸附适宜的水溶液pH值为5,吸附时间为30 min,此时0.6g树皮粉对100 mL初始质量浓度为150 mg/L的重金属离子溶液Cu2＋、Cd2＋和Pb2＋的吸附量分别为6.83、13.56和23.17 mg/g.45℃下等温吸附过程符合Freundlich和Langmuir等温吸附模型,但Langmuir等温吸附模型拟合相关性更高;吸附动力学符合Lagergren准二级动力学模型,拟合相关性R2大于0.997.说明杉木树皮粉可作为水溶液中重金属离子的有效吸附剂,其吸附主要为单分子层的化学吸附.The adsorption of copper, lead and cadmium ions （heavy metal ions, HMI） from aqueous solution by the powder of fir bark was investigated by using batch techniques. The effects of pH value, contact time and initial metal ions concentration and particle size of fir bark powder on the metal ions adsorption capacity have been studied. Fir bark was found to be a low cost and promising adsorbent for absorbing heavy metal ions from aqueous solution. The results showed that the suitable size of bark powder used as adsorbent is 250-830 μm. Under the condition with pH of 5.0 and a contact time of 30 min, 0.6 g bark powder in 100 mL initial ions concentration of 150 mg,/L resulted in themaximum adsorption capacity of 6.83, 13.56 and 23.17 mg/g for Cu2＋ , Cd2＋ and Pb2＋ , respectively. Kinetics fitted with Lagergren pseudo second-order models. Hence adsorption kinetic parameters were calculated, and the correlation coefficient R2 〉 0.997 was obtained. The adsorption data of metal ions at 45 ℃ has been described by the Freundlich and Langmuir isothermal absorption models, and Langmuir isothermal adsorption model was more satisfied. Ion exchange was probably one of the major adsorption mechanisms for binding divalent metal ions to the bark powder. From these results, it can be concluded that the powder of the fir bark could be a good adsorbent for extracting the metal ions from aqueous solution. Key words： fir bark;adsorption;heavy metal ions;adsorption kinetic;isothermal adsorption model

关 键 词：杉木树皮 吸附 重金属离子 吸附动力学 等温吸附模型 

分 类 号：TQ35[化学工程]