落叶松单宁原位固化及其对Au(Ⅲ)吸附性能的研究  

In situ immobilization of tannin of Larix gmelini and its adsorption to Au(Ⅲ)

作　　者：侯旭[1] 廖学品[1] 石碧[1] 

机构地区：[1]四川大学皮革化学与工程教育部重点实验室

出　　处：《北京林业大学学报》2006年第1期71-75,共5页Journal of Beijing Forestry University

基　　金：国家自然科学基金资助项目(20476062);国家杰出青年基金项目(20325619).

摘　　要：以富含单宁的落叶松树皮为原料制备吸附材料,研究了该吸附材料对水溶液中Au(Ⅲ)的吸附特性.结果表明:以甲醛作为交联剂可以实现落叶松树皮中单宁的原位固化;当温度为303K,pH=4.0,Au(Ⅲ)的初始浓度为522.3mgL时,该吸附材料对Au(Ⅲ)的平衡吸附量达到Au(Ⅲ)1821.9mgg,而且平衡吸附量随温度的升高进一步增大.pH对吸附容量的影响较大,最佳pH为4.0.该吸附材料对Au(Ⅲ)的吸附平衡符合Langmuir方程,吸附动力学可以用拟二级速度方程来描述.固定床吸附实验表明,当原料液的浓度为Au(Ⅲ)239.2mgL,流出液的体积约为117个床层体积时才达到穿透点.分析表明,原位固化落叶松单宁对Au(Ⅲ)的吸附为氧化还原吸附.Tannins in the bark of Larix gmelini were immobilized in situ by cross-linking reaction of formaldehyde. The adsorption behavior of this new adsorbent to Au （ Ⅲ ） in aqueous solution was investigated. It was found that the adsorption capacity of this adsorbent to Au（ Ⅲ ） was Au 1 821.9 mg/g at 303 K when the initial concentration of Au（ Ⅲ） was 522.3 mg/L.The optimal pH for the adsorption of Au（ Ⅲ ） was 4.0, and that higher temperature led to higher adsorption capacity. The adsorption isotherm of Au （ Ⅲ） on the immobilized tannin of L. gmelini could be described by the Langmuir equation. The data of adsorption rate could be well fitted by the pseudo-second-order rate model. The breakthrough point of adsorption column was at 117 bed volumes when the inlet concentration of Au （Ⅲ） was 239.2 mg/L, indicating that this adsorbent has outstanding ability of recovering Au （Ⅲ）. Further studies indicated that the adsorption mechanism of immobilized tannin of L. grnelini to Au（ Ⅲ ） was mainly redox adsorption.

关 键 词：落叶松单宁 落叶松树皮 原位固化 吸附 Au(Ⅲ) 

分 类 号：S791.22[农业科学—林木遗传育种] S781.42[农业科学—林学]