(1. 南華大學(xué) 生物化學(xué)與分子生物學(xué)國(guó)防支撐學(xué)科實(shí)驗(yàn)室，衡陽(yáng) 421001；
2. 南華大學(xué) 化學(xué)化工學(xué)院，衡陽(yáng) 421001；
3. 中南大學(xué) 資源與安全工程學(xué)院，長(zhǎng)沙 410083；
4. 長(zhǎng)沙理工大學(xué) 化學(xué)與生物工程學(xué)字院，電力與交通材料保護(hù)湖南省重點(diǎn)實(shí)驗(yàn)室，長(zhǎng)沙 410004)
摘 要: 為了解決耐輻射奇球菌(DR)容易以懸浮態(tài)生長(zhǎng)，菌體與水的密度差較小，吸附鈾后難以分離等問(wèn)題，首先使用氯化亞砜對(duì)羧基化磁性納米Fe3O4粒子進(jìn)行酰氯功能化，以此作為DR菌固定載體，再與二乙烯三胺化學(xué)修飾的DR菌進(jìn)行固定化，得到一種新型功能化磁性耐輻射奇球菌吸附劑NFGDR，并通過(guò)紅外光譜儀和掃描電鏡分別表征吸附劑NFGDR的結(jié)構(gòu)。考察溶液pH值、吸附時(shí)間、鈾初始濃度和吸附劑投加量等因素對(duì)吸附劑NFGDR吸附鈾的影響，對(duì)吸附動(dòng)力學(xué)模型和吸附等溫模型進(jìn)行分析。結(jié)果表明:吸附劑NFGDR表面具有大量吸附鈾的基團(tuán)，吸附鈾后表面形態(tài)發(fā)生變化；吸附鈾的最佳條件是pH值為5、吸附時(shí)間為80 min、鈾初始濃度為10 mg/L和吸附劑投加量為5 mg。吸附劑NFGDR對(duì)鈾的吸附動(dòng)力學(xué)過(guò)程符合準(zhǔn)二級(jí)動(dòng)力學(xué)模型， 吸附等溫線符合Langmuir等溫線模型，說(shuō)明該吸附體系是一個(gè)單層吸附過(guò)程。同時(shí)，使用3種不同的解析劑對(duì)吸附劑NFGDR解析再生6次后，其對(duì)鈾的吸附率均在80%以上，說(shuō)明其具有良好的再生性能。
關(guān)鍵字: 功能化；磁性載體；耐輻射奇球菌；鈾；吸附機(jī)理
（1. Support Discipline Laboratory of National Defence for Biochemistry and Molecular biology,
University of South China, Hengyang 421001, China;
2. School of Chemistry and Chemical Engineering, University of South China, Hengyang 421001, China;
3. School of Resources and Safety Engineering, Central South University, Changsha 410083, China;
4. The Key Laboratory of Powder and Transport Materials Protection in Hunan Province, College of Chemistry and Chemical Engineering, Changsha University of Science & Technology, Changsha 410004, China）
Abstract:In order to solve the problems such as Deinococcus radiodurans (DR) growing in a suspended state, the small difference between the bacteria density and the water density, and the hard separation after uranium adsorption, the novel functional magnetic Deinococcus radiodurans adsorbent NFGDR was prepared. At first, the carboxylation magnetic Fe3O4 nanoparticle was chloride functionalization using sulfoxide chloride, and it was immobilized with the chemical modification DR using Diethylenetriamine as the magnetic carrier. FT-IR and SEM were used to characterize NFGDR, and the effects of pH value, adsorption time, initial concentration of uranium and the adsorbent dosage on the adsorption of NFGDR on uranium were investigated. The adsorption kinetic models and the adsorption isotherm models of NFGDR on uranium were studied. The results show that a lot of functional groups are found on the cell wall of NFGDR for adsorbing uranium , and its surface form changes because of adsorbing uranium. The optimal uranium adsorption conditions are as follows: the pH of the solution is 5; the adsorption time is 80 min; the initial concentration of uranium is 10 mg/L and the adsorbent dosage is 5 mg. The kinetic model of NFGDR can be described by the pseudo-second-order model well, and the isotherm model is fitted to Langmuir adsorption model, indicating that the adsorption process is a monolayer cover adsorption process. At the same time, the uranium adsorption percents are over 80% after NFGDR was regenerated 6 times using 3 different analytical agents. It shows that NFGDR has good regeneration performance.
Key words: functionalization; magnetic carrier; Deinococcus radiodurans; uranium; adsorption mechanism
