物理化学学报 >> 2012, Vol. 28 >> Issue (05): 1223-1229.doi: 10.3866/PKU.WHXB201202234

催化和表面科学 上一篇    下一篇

改性碳纳米管常温下吸附分离低浓度CO2

叶青1, 张瑜1, 李茗2, 施耀1   

  1. 1. 浙江大学工学部化学工程与生物工程系工业生态与环境研究所, 杭州 310028;
    2. 浙江树人大学, 杭州 310015
  • 收稿日期:2011-10-18 修回日期:2012-01-18 发布日期:2012-04-26
  • 通讯作者: 施耀 E-mail:shiyao@zju.edu.cn
  • 基金资助:

    国家自然科学基金(20976159)资助项目

Adsorption of Low Concentration CO2 by Modified Carbon Nanotubes under Ambient Temperature

YE Qing1, ZHANG Yu1, LI Ming2, SHI Yao1   

  1. 1. Institute of Industrial Ecology and Environment, Department of Chemical and Biological Engineering, Faculty of Engineering, Zhejiang University, Hangzhou 310028, P. R. China;
    2. Zhejiang Shuren University, Hangzhou 310015, P. R. China
  • Received:2011-10-18 Revised:2012-01-18 Published:2012-04-26
  • Contact: SHI Yao E-mail:shiyao@zju.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (20976159).

摘要: 采用浸渍法将四乙烯五胺(TEPA)和三乙烯四胺(TETA)负载至碳纳米管(CNTs)上, 得到一种固态胺吸附剂CNTs-TEPA和CNTs-TETA, 用以吸附低浓度下的CO2. 利用扫描电镜(SEM)、透射电镜(TEM)、傅里叶红外(FTIR)光谱、N2 物理吸附脱附、元素分析和热重分析(TGA)等方法表征样品. 结果表明: CNTs-TEPA 和CNTs-TETA形态并未发生变化, 仍保留CNTs 规整有序的孔道结构, 但样品的比表面积和孔容都显著减小. 在常温条件下, CNTs-TEPA和CNTs-TETA的CO2吸附量与CNTs 相比有显著提高, 同时, 在胺浸渍质量相同的情况下, 改性后的CNTs-TEPA 效果优于CNTs-TETA. 温度从20 ℃升至30 ℃, CNTs-TEPA 和CNTs-TETA 的CO2吸附量分别从126.7、101.2 mg·g-1升至139.3、110.4 mg·g-1. CNTs 的吸附量随着温度的增加变化不明显. 最后, 采用Suyadal 和Yasyerli 两种模型对CO2的动态吸附穿透曲线进行拟合, 结果说明Yasyerli 模型对CNTs、CNTs-TEPA和CNTs-TETA的CO2吸附过程的拟合程度更高.

关键词: 碳纳米管, CO2吸附, 三乙烯四胺, 四乙烯五胺, 失活模型

Abstract: Solid amine adsorbents for low concentration CO2 removal were developed using carbon nanotubes (CNTs) impregnated with tetraethylenepentamine (TEPA) and triethylenetetramine (TETA). The adsorbents were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FITR), N2 adsorption/desorption, elemental analysis and thermogravimetric analysis (TGA). After impregnation, the shapes, fundamental channels and pore structures of the adsorbents were unchanged. However, the surface area and pore volume decreased. The adsorption behavior toward low concentration CO2 was investigated in a fixed-bed column. The results indicated that the adsorption capacity was enhanced substantially by modification. The CO2 adsorption capacity of CNTs-TEPA was higher than that of CNTs-TETA with the same amount of amine loading. The adsorption capacity increased steadily from 126.7 to 139.3 mg·g-1 for CNTs-TEPA and from 101.2 to 110.4 mg·g-1 for CNTs-TETA as the temperature increased from 20 to 30 ℃. The adsorption capacity of the raw CNTs experienced a modest increase, but began to decrease gradually with further temperature increases. Suyadal and Yasyerli deactivation models were applied to investigate the experimental breakthrough curves of raw and modified CNTs. It was concluded that the Yasyerli deactivation model is more appropriate to analyze the breakthrough curves of CO2 adsorption on solid amine adsorbents.

Key words: Carbon nanotube, CO2 adsorption, Triethylenetetramine, Tetraethylenepentamine, Deactivation model

MSC2000: 

  • O647