水溶液中趋磁微生物体吸附Ni^(2+)的模拟研究  

SIMULATION ON BIOSORPTION OF Ni^(2+) BY MAGNETOTACTIC MICROORGANISM IN AQUEOUS SOLUTION

作　　者：宋慧平[1] 成怀刚[1] 程芳琴[1] 

机构地区：[1]山西大学资源与环境工程研究所,太原030006

出　　处：《离子交换与吸附》2011年第5期392-399,共8页Ion Exchange and Adsorption

基　　金：国家自然科学基金(No.20906053);山东省自然科学基金(NO.ZR2009BQ002)

摘　　要：为了探索趋磁微生物体对水溶液中Ni2+的吸附机理,考察微观作用力对吸附过程的影响,本文通过酸碱滴定实验确定了趋磁微生物体具有吸附作用的表面功能基团,建立了由体内磁小体Fe3O4和表面功能基团-PO3H,-OH,-COOH构成的趋磁生物体模型,并通过分子动力学模拟方法从静电作用、分子间作用、热运动等方面研究了磁小体和功能基团对Ni2+的吸附过程的影响规律。模拟结果证明对Ni2+的吸附过程是基团的静电吸引力和范德华力相互作用的综合结果,不同基团的静电引力强弱是有区别的。模拟结果还表明,Ni2+对-PO3H的趋聚倾向最大,对-OH的趋聚倾向次之,而对-COOH和Fe3O4的趋聚作用较弱。采用化学修饰法分别掩蔽菌体表面基团,并做了吸附实验,吸附效果与模拟结果完全吻合。这些结论将对生物磁选的开发应用提供新的理论依据。For exploring the biosorption mechanism of magnetotactic microorganism in aqueous solution on microscope level, the species and concentrations of functional groups on the biomass were determined by potentiometric titration. The abstracted physical model of magnetotactic microorganism was built as the group composed of -PO3H, -OH, -COOH and Fe3O4. The adsorption characters of this group were examined by molecular dynamics simulation from the angles of Coulomb force and Van der Waals force. The results showed that electrostatics and thermal motion had effects on the motion of Ni^2＋, and the electrostatics of different functional groups was dissimilar. Collective tendency probability of -PO3H toward Ni^2＋ was the largest, and that of -COOH and Fe3O4 were small comparatively. The functional groups on the biomass were modified using different chemical reagent, respectively. Then, chemical modified biomass was used as adsorbent for adsorb Ni^2＋, and the experimental results agreed well with the simulating results. All above could provide new useful references for the application of bio-magnetic separation.

关 键 词：趋聚 生物吸附 库仑力 范德华力 

分 类 号：TQ085.41[化学工程]