(北京科技大學(xué) 土木與環(huán)境工程學(xué)院，北京 100083)
摘 要: 研究溶液pH值、Cu2+初始濃度、吸附時間、吸附劑投加量及溫度對中藥渣和麥麩吸附模擬礦山酸性廢水中較高濃度Cu2+的影響。結(jié)果表明，隨pH值的升高中藥渣和麥麩對Cu2+的吸附量均增大；吸附劑最佳投加量為10 g/L；吸附過程更好地符合擬二級動力學(xué)模型；在pH值為3時，二者的最大吸附量分別為14.03和7.34 mg/g，吸附平衡符合Langmuir等溫線方程；熱力學(xué)研究表明，二者對Cu2+的吸附為非自發(fā)的放熱反應(yīng)。Zeta電位顯示中藥渣和麥麩在水溶液中均帶負(fù)電，能夠以靜電引力吸附Cu2+；紅外光譜分析表明，中藥渣吸附Cu2+的官能團(tuán)主要為羥基、羧基、酰胺基和酯基等，而麥麩吸附Cu2+的主要官能團(tuán)為羥基、酰胺基和硅氧基等。
關(guān)鍵字: 礦山酸性廢水；中藥渣；麥麩；生物吸附
（School of Civil and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China）
Abstract:Effective parameters including solution pH, initial Cu2+ concentration, contact time, mass of adsorbents and temperature were studied to assess the biosorption of high Cu2+ ions from simulated acid mine drainage by herb-medicine residues and wheat bran. The results show that biosorption capacities of both of them increase with the raising solution pH; the addition of adsorbents is optimized to be 10 g/L; pseudo-second-order model is more suitable for biosorption processes. The maximum biosorption capacities are 14.03 and 7.34 mg/g, respectively at solution pH value of 3; Langmuir model is observed to fit well. Thermodynamics analysis indicates that biosorption processes of herb-medicine residues and wheat bran are exothermic and unspontaneous. By means of Zeta potentials, it is found that both herb-medicine residues and wheat bran bear negative charges in solution, which can adsorb Cu2+ by electrostatic pull. For FT-IR spectrum, the results indicate that the functional groups of herb-medicine residues are hydroxyl, carboxyl, amide and ester, while the functional groups of wheat bran are hydroxyl, amide and silicon-oxygen groups.
Key words: acid mine drainage; herb-medicine residues; wheat bran; biosorption
