摘要
将花生壳（PS）改性制备成花生壳生物炭（PSB），研究了吸附时间（10～5760 min）、吸附剂用量（0.1～5 g）、镉离子溶液初始 pH值（1～8）和浓度（10～800 mg·L-1）等因素对 Cd2＋去除效率的影响；利用场发射扫描电镜（SEM）、傅里叶红外光谱（FTIR）与模型拟合分析，探讨了 PS 和 PSB 的吸附性能与机理。实验结果表明，PS 和 PSB 是优良的生物质基吸附材料；pH 为5.0、Cd2＋溶液浓度为10 mg· L-1、吸附剂添加量为4 mg·mL-1时，PS 的去除效率为93.33豫，PSB 的去除效率为99.51豫；吸附容量分别可达26.88 mg·g-1、28.99 mg·g-1；Freundlich 与 Langmuir 吸附模型均能较好地描述 PS 和 PSB 对 Cd2＋的等温吸附过程，以 Freundlich 模型略优。SEM 电镜扫描和 FTIR 图谱分析表明 PS 和 PSB 对镉的吸附主要为多分子层的表层络合吸附：SEM 分析表明 PS 和 PSB 在吸附 Cd2＋以后表面具有大量的颗粒附着物；FTIR 分析表明 PS 与 PSB 吸附镉的主要机理为络合反应，PS 参与络合反应的主要官能团为-CHO、-C=O、-OH和-P=O，PSB 参与络合反应的主要官能团为-C=C-、-C以C-、-C以N 和-OH 等官能团。
Peanut shell is waste from agriculture and industry. This study was conducted to investigate the potential of peanut shell（PS）and its biochar（PSB）to remove cadmium（Cd2＋）from aqueous solution under different conditions including pH, initial Cd2＋ concentrations, ad-sorbent doses and time. The surface characteristics and mechanism of Cd adsorption were also investigated using scanning electron micro-scope, Fourier transform infrared spectroscopy（FTIR）, BET specific surface area analyses and model simulation. Both PS and PSB were excellent adsorbents for Cd2＋. At pH 5, 10 mg·L-1 of Cd2＋ concentration and 4 mg·mL-1 of adsorbent, Cd2＋ removal efficiencies were 93.33%and 99.51% for PS and PSB, respectively. The maximum adsorption for Cd2＋ was respectively 26.88 mg·g -1 and 28.99 mg·g-1 for PS and PSB. Freundlich and Langmuir models could be used to describe the adsorption data, with the former better than the latter. The adsorption was mainly polymolecular layer adsorption and the complexation was one of the adsorption mechanisms. The main functional groups involved in the complexation were -CHO,-C=O,-OH and-P=O for PS;while-C=C-,-C以C-,-C≡N and -OH for PSB. The SEM and FTIR analyses showed that a lot of particles or ash substances were deposited on the surface of PS and PSB after adsorption of Cd2＋.
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2014年第10期2022-2029,共8页
Journal of Agro-Environment Science
基金
国家科技支撑计划项目(2014BAD14B04)
中国科学院重点部署项目(No.KZZD-EW-16-02)
关键词
花生壳
花生壳生物炭
镉
傅里叶红外
等温吸附模型
生物质基材料
peanut shells（PS） peanut shell derived biochar（PSB） cadmium（II） Fourier Transform infrared spectroscopy（FTIR） isotherm models
biomass-based material
