(1. 南華大學(xué)化學(xué)化工學(xué)院，衡陽 421001；
2. 南華大學(xué)鈾礦冶生物技術(shù)國防重點(diǎn)學(xué)科實(shí)驗(yàn)室，衡陽 421001；
3. 中南大學(xué)資源與安全工程學(xué)院，長沙 410083；
4. 南華大學(xué)船山學(xué)院，衡陽 421001)
摘 要: 采用啤酒酵母菌為生物大孔模板，三嵌段聚合物(P123)為介孔相模板制備合成介孔氧化硅SBA-15。再采用Fe3O4為鐵源，二乙基磷酰乙基三乙氧基硅烷(PTS)和氨丙基三乙氧基硅烷(APS)為有機(jī)改性基團(tuán)，通過后嫁接法使有機(jī)改性基團(tuán)對介孔氧化硅SBA-15進(jìn)行功能化改性，得到新型功能化吸附劑G-PA-SBA-15，并通過掃描電鏡、粉末X射線衍射和比表面分析儀分別表征吸附劑G-PA-SBA-15和SBA-15的結(jié)構(gòu)。考察溶液pH值、吸附時(shí)間、鈾初始濃度和溫度等因素對吸附劑G-PA-SBA-15和SBA-15吸附鈾的影響。結(jié)果表明：吸附劑G-PA-SBA-15直徑均勻分布、孔徑均一，吸附鈾的最佳條件是pH值為6.0、吸附時(shí)間為1.0 h、鈾初始濃度為20 mg/L和吸附反應(yīng)溫度為25 ℃。對吸附動(dòng)力學(xué)模型和吸附等溫模型進(jìn)行分析，G-PA-SBA-15對鈾的吸附動(dòng)力學(xué)過程符合準(zhǔn)二級動(dòng)力學(xué)模型(相關(guān)系數(shù)R2均大于0.99)，吸附等溫線符合BET等溫線模型，說明該吸附體系是一個(gè)多層吸附過程。
關(guān)鍵字: 介孔氧化硅SBA-15; 功能化改性; 鈾; 吸附動(dòng)力學(xué); 吸附等溫線
（1. School of Chemistry and Chemical Engineering, University of South China, Hengyang421001, China;
2. Key Discipline Laboratory for National Defence for Biotechnology in Uranium Mining and Hydrometallurgy,
University of South China,Hengyang421001, China;
3. School of Resources and Safety Engineering, Central South University, Changsha 410083, China;
4. Wang Chuanshan College, University of South China, Hengyang421001, China）
Abstract:Mesoporous silica SBA-15 was synthesized using Saccharomyces Cerevisiae as the biological macroporous templet, and using P123 as the mesoporous phase templet. The novel functional adsorbent G-PA-SBA-15 was prepared using Fe3O4 as the iron source, and using PTS and APS as the organic modification group by the functional modification of mesoporous silica SBA-15 after grafting. SEM, XRD and BET were used to characterize the structures of G-PA-SBA-15 and SBA-15, and the effects of pH value, adsorption time, initial concentration of uranium ions and temperature on the adsorption of G-PA-SBA-15 and SBA-15 on uranium were investigated. The results show that the optimal uranium adsorption conditions are as follows: the pH of the solution is 6.0; the adsorption time is 1.0 h; the initial concentration of uranium ions is 20 mg/L and the adsorption temperature is 25 ℃. The adsorption kinetic models and the adsorption isotherm models of G-PA-SBA-15 on uranium were studied. The kinetic models of G-PA-SBA-15 can be described by the pseudo-second-order model well, its correlation coefficient are all above 0.99 (R2>0.99), and isotherm models are fitted to BET adsorption models, indicating that the adsorption process is a multilayer adsorption process.
Key words: mesoporous silica SBA-15; functional modification; uranium; adsorption kinetics; adsorption isotherm
