化工学报 ›› 2012, Vol. 63 ›› Issue (3): 916-923.DOI: 10.3969/j.issn.0438-1157.2012.03.034

• 能源和环境工程 • 上一篇    下一篇

热处理对凹凸棒石结构及其脱硫性能的影响

张先龙,姜伟平,吴雪平,时博文,杨保俊,贾小彬,张翠平   

  1. 合肥工业大学化学工程学院
  • 收稿日期:2011-03-14 出版日期:2012-03-05 发布日期:2012-03-05
  • 通讯作者: 张先龙

Effect of heat treatment on structural character and desulfurization capability of palygorskite

ZHANG Xianlong,JIANG Weiping,WU Xueping,SHI Bowen,YANG Baojun,JIA Xiaobin,ZHANG Cuiping   

  • Received:2011-03-14 Online:2012-03-05 Published:2012-03-05

摘要: 凹凸棒石是一种性能优良的吸附材料,对小分子极性气体具有很好的吸附性,适宜的煅烧处理可以提高其吸附活性。考察了凹凸棒石经过不同条件热处理后对烟气中SO2吸附性能的变化行为。利用XRD、BET和TPD等方法表征了凹凸棒石脱硫剂在热处理过程中的结构变化。探讨凹凸棒石脱硫剂的结构特性与其脱硫性能的内在关系。研究发现:凹凸棒石的微观晶体结构随热处理温度的升高呈现显著的阶段性变化,而SO2吸附实验结果表明,这种结构变化的程度与凹凸棒石表面不同形态水分子的脱除密切相关。随着热处理温度的升高,凹凸棒石对SO2的吸附量呈现先增大后减少的趋势;凹凸棒石的表面吸附水和沸石水的存在占用大量的吸附位,对SO2的吸附是不利的;而结晶水的存在对SO2的吸附是有利的。

关键词: 凹凸棒石, SO2, 热处理, 烟气脱硫

Abstract: Palygorskite as an excellent adsorbent material shows a predominant performance on the adsorption of small gaseous polar molecules, which can be remarkably improved by suitable thermal treatment. In this study, the SO2 removal from the flue gas is investigated with the palygorskite treated at different temperatures. The structural transformation of palygorskite desulfurizer during the heat treatment process was characterized by XRD,BET and TPD. A correlation between structural characteristics and desulfurization performance of palygorskite adsorbent was discussed. Results indicate that, as the heat treatment temperature increases, the micro-crystal structure of palygorskite displays significant step changes, which is suggested to be closely related to the removal of water in different forms from palygorskite surface. The adsorption capacity of SO2 on palygorskite first increases and then decreases as the heat treatment temperature increases. Based on these results, it can be deduced that the water adsorbed on the surface and that in the pores of palygorskite inhibit the adsorption of SO2, but the crystalline water is favorable for SO2 adsorption.

Key words: palygorskite, SO2, heat treatment, flue gas desulfurization