木纤维对Sr^(2+)和Cs^+的吸附性能及机理研究  

STUDY ON ADSORPTIVE PROPERTY AND MECHANISM OF WOOD FIBER FOR Sr^(2+) AND Cs^+

作　　者：冯媛[1] 易发成[1] 

机构地区：[1]西南科技大学国防科工委核废物和环境安全国防重点学科实验室,四川绵阳621010

出　　处：《水处理技术》2011年第4期23-28,共6页Technology of Water Treatment

基　　金：国防科研项目(A3120080126);国家自然科学基金项目(10376028)

摘　　要：采用间歇法研究了木纤维对Sr2+、Cs+的吸附作用,探讨了木纤维的粒度、溶液的pH、不同介质、吸附时间、温度及木纤维用量等因素对Sr2+、Cs+吸附效果的影响,并用准2级动力学模型、扫描电镜、红外光谱及能谱图分析了吸附机理。结果表明,在室温、木纤维用量为0.2 g、浓度分别均为0.5 mmol·L-1的Sr2+、Cs+溶液50 mL、pH为5.0、振荡吸附时间分别为120和60 min的条件下,Sr2+的吸附去除率达到82.4%,Cs+则只有25%;木纤维对Sr2+、Cs+的吸附使表面形态发生变化,其吸附动力学行为符合准2级吸附速率模型(R2分别为0.999 9和1.000);与Sr2+、Cs+相互作用的基团主要是羟基、碳氢键、碳碳双键和亚甲基,木纤维吸附Sr2+、Cs+的过程中存在离子交换。因此,木纤维对Sr2+、Cs+的属于物理和化学混合吸附类型。A intermittence method was adopted to study the adsorption of wood fiber for Sr^2＋ and Cs^＋ under various conditions including different adsorbent size, pH, media, adsorption time, temperature and dosage of adsorbent, and mechanisms for Sr〉 and Cs^＋ removal were discussed by FTIR and energy spectrum analysis. When 0.2 g wood fiber dissolved in 50 mL solution, with Sr〉 and Cs^＋ concentration 0.5 mmol·L^-1, pH=5.0, then batch adsorpted respectively for 120 rain and 60 rain at room temperature, the removal rate of Sr^2＋ achieved 82.4%, while Cs^＋ was 25%. The biosorption kinetics can be described by the pseudo second-order equation quite well （R2=0.999 9 and 1.000）. FTIR analysis indicated that hydroxyl, hydrogen bond, carbon-carbon bond and methylene groups were the main functional groups in the reaction with Sr^2＋ and Cs^＋. Energy spectrum analysis indicated that wood fiber adsorption process of uranium ions existed in ion exchange. Therefore, there was physical adsorption and chemical adsorption existing in the adsorption process, which adsorption types were mixed.

关 键 词：木纤维 Sr^2+ Cs^+ 吸附性能 机理 

分 类 号：TQ424[化学工程]