改性谷壳生物炭负载磁性Fe去除废水中Pb^(2+)的效果及机制  

Effects and mechanisms of magnetic iron supported on rice husk biochar removing Pb^(2+) in wastewater

作　　者：曹玮[1] 周航[1] 邓贵友[1] 杜文琪[1] 杨文弢 辜娇峰[1] 彭佩钦[1] 廖柏寒[1] CAO Wei ZHOU Hang DENG Guiyou DU Wenqi YANG Wentao GU Jiaofeng PENG Peiqin LIAO Bohan(College of Environment Science and Engineering, Central South University of Forestry and Technology, Changsha 410004,China)

机构地区：[1]中南林业科技大学环境科学与工程学院,长沙410004

出　　处：《环境工程学报》2017年第3期1437-1444,共8页Chinese Journal of Environmental Engineering

基　　金：国家自然科学基金资助项目(41501344);农业部与财政部科研专项(农办财函[2014]28号);湖南省重点学科建设项目(2006180)

摘　　要：将谷売生物炭用酸改性后负载磁性Fe_3O_4,得到一种新的吸附材料(BC^Fe)。通过单因素吸附实验,研究了时间、pH、添加量、浓度以及温度等参数对BCTe吸附废水中Pb^(2+)的影响,并对其进行比表面积及傅里叶红外光谱分析,探讨该磁性生物炭对Pb^(2+)的吸附机理。结果表明对Pb^(2+)的吸附能在2 h内基本达到平衡。在Pb^(2+)溶液初始浓度为100mg·L^(-1),pH=5.0温度为25℃,分別添加0.1g和0.15 g的BC-Fe于50 mL Pb^(2+)溶液中,单位质量的BC-Fe对溶液中Pb^(2+)的吸附量分别为40.6 mg·g^(-1)和33.2 mg·g^(-1)去除率分别为81.3%和99.9%。该吸附过程符合拟二级动力学模型,理论平衡吸附量为43.9 mg·g^(-1)。用Langmuir等温吸附方程能够很好地描述其吸附行为;热力学研究表明对Pb^(2+)的吸附过程是自发的吸热过程。In this study rice husk biochar was modified by acid and loaded with magnetic nano-Fe3O4,forming a new adsorbent material（named BC-Fe）.A one-factor batch experiment was conducted using BC-Fe to remove Pb^2＋ ions from simulated wastewater,considering such factors as contact time,solution pH,adsorbent dose,initial Pb^2＋ concentration,and temperature.Meanwhile,the specific surface area and Fourier transform infrared spectra of BC-Fe were analyzed.The purpose of this study was to investigate the characteristics and mechanisms of Pb adsorption from wastewater onto BC-Fe.The results showed that the adsorption equilibrium was reached within 2 h.Under the conditions of an initial Pb^2＋ concentration of 100 mg·L^-1,a solution pH of 5.0,and a temperature of 25℃,the Pb^2＋ adsorption capacity and removal ratio achieved using 0.1 g of BC-Fe in 50 mL Pb^2＋ solution were 40.6 mg·g^-1 and 81.3%/respectively.The corresponding values for 0.15 g of BC-Fe were and33.2 mg·g^-1 and 99.9%.The adsorption reaction of Pb^2＋ onto BC-Fe was well described by quasi-two-level dynamics,and the equilibrium adsorption capacity was 43.9 mg·g^-1.The adsorption of Pb^2＋ onto BC-Fe was well fitted by the Langmuir adsorption isotherm model,and the thermodynamics data indicated that the adsorption of Pb^2＋ onto BC-Fe was spontaneous and endothermic.

关 键 词：生物炭 磁性 PB^2+ 吸附 机理 废水 

分 类 号：X703[环境科学与工程—环境工程]