(1. 中南大學(xué) 資源加工與生物工程學(xué)院，長(zhǎng)沙 410083；
2. 中南大學(xué) 生物冶金教育部重點(diǎn)實(shí)驗(yàn)室，長(zhǎng)沙 410083)
摘 要: 在N,N-二甲基甲酰胺中，以次磷酸鈉作為催化劑，采用檸檬酸對(duì)泡桐皮、蘆葦、花生葉3種生物質(zhì)材料進(jìn)行化學(xué)改性，制備得到生物吸附劑，并研究Cr(Ⅵ)溶液pH值、初始溶液Cr(Ⅵ)濃度、吸附時(shí)間等因素對(duì)水溶液中Cr(Ⅵ)吸附率的影響。采用紅外光譜分析儀對(duì)吸附材料的分子結(jié)構(gòu)及其化學(xué)鍵進(jìn)行表征。結(jié)果表明：3種改性生物質(zhì)材料在pH值為2、Cr(Ⅵ)初始濃度為30 mg/L時(shí)，吸附性能較好，吸附平衡時(shí)間為120 min。可以用準(zhǔn)二級(jí)動(dòng)力學(xué)方程很好地描述生物質(zhì)材料吸附過程。改性后的泡桐皮、蘆葦、花生葉對(duì)Cr(Ⅵ)的最大吸附率分別為96.78%、91.85%和89.63%，其中改性后泡桐皮具有最大的吸附量。
關(guān)鍵字: 泡桐皮；蘆葦；花生葉；Cr(Ⅵ)；化學(xué)改性；重金屬；生物質(zhì)吸附
（1. School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China;
2. Key Laboratory of Biometallurgy, Ministry of Education, Central South University, Changsha 410083, China）
Abstract:Paulownia peel, reed and peanut leaf were chemically modified with citric acid by using sodium hypophosphite monohydrate (NaH2PO2·H2O) as a catalyst in N,N-dimethylformamide (DMF) to obtain biosorbents. The effects of pH of Cr(Ⅵ) solution, initial concentration of Cr(Ⅵ), adsorption time on the adsorption efficiency of Cr(Ⅵ) in aqueous solution were investigated. Fourier transform infrared spectroscopy were used to characterize the molecular structure and its chemical bond of the adsorbent. The results show that, when pH value is 2 and the initial concentration of Cr(Ⅵ) is 30mg/L, three biomass materials have superior adsorptive properties. The adsorption processes achieves equilibrium within 120 min and are found to be well described by the pseudo-second order adsorption kinetics. The maximum adsorption efficiencies of Cr(Ⅵ) by modified paulownia peel, reed and peanut leaf are 96.78%, 91.85% and 89.63%, respectively. Among these biosorbents, the modified paulownia peel has the highest adsorption quantity.
Key words: paulownia peel; reed; peanut leaf; Cr(Ⅵ); chemical modification; heavy metal; biomass adsorption
