中华医学超声杂志

应用化学 ›› 2010, Vol. 27 ›› Issue (03): 338-341.DOI: 10.3724/SP.J.1095.2010.90242

• 研究论文 • 上一篇    下一篇

水滑石型固体碱碱性位的内标CO2-TPD-MS表征

黄登通,柯国梁,苏抒,杨乐夫*,方维平   

  1. (厦门大学化学化工学院,醇醚酯清洁化工生产国家工程实验室 厦门 361005)
  • 收稿日期:2009-04-07 修回日期:2009-07-01 出版日期:2010-03-10 发布日期:2010-03-10
  • 通讯作者: 杨乐夫,男,副教授; E-mail:lfyang@xmu.edu.cn; 研究方向：多相催化与能源化工
  • 基金资助:
    厦门大学“大学生创新性实验计划”项目；教育部科学技术研究重大（307017）资助项目

Internal standard quantitative characterization of basic sites on Mg-Al hydrotalcites by CO2-TPD-MS technique

HUANG De-Tong, KE Guo-Liang, SU Shu, YANG Le-Fu*, FANG Wei-Ping   

  1. (State Engineering Laboratory for Green Chemical Productions of Alcohols,Ethers and Esters,
    College of Chemistry and Chemical Engineering,Xiamen University,Xiamen 361005)
  • Received:2009-04-07 Revised:2009-07-01 Published:2010-03-10 Online:2010-03-10

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摘要：

通过共沉淀法制备了一系列不同镁铝比的水滑石样品，依据物相分析与热失重实验结果确认了合成的样品具有水滑石结构。以方解石型CaCO3为内标，对水滑石样品碱性位的CO2-TPD定量表征进行校正，并比较了不同实验参数对方法精密度的影响。经过各测试参数的敏感性分析证实，用CaCO3脱附峰面积校正后，水滑石碱密度测量结果的RSD分别由9.7%、12.3%下降为4.3%、7.3%，而汇总分析的RSD可从29.6％下降至6.6%。CO2-TPD定量分析精密度明显提高，证实了内标法的优势及其应用于固体碱定量表征的可行性。将内标法所得结果与固体碱催化酯交换反应的性能关联，结果发现，水滑石催化性能受到活性相的碱强度与碱密度双重指标的调控，碱强度和碱密度越大，酯交换催化效率越高。

关键词: CO2-TPD, 水滑石, 碱密度, 酯交换, 固体碱

Abstract:

A series of hydrotalcite samples with varied Mg/Al ratio are synthesized by coprecipitation route. Quantitative analysis on the basic sites of hydrotalcite samples is carried out by CO2-TPD technique which is calibrated by calcium carbonate internal standard, and the effects of various experimental factors on the precision of testing results are evaluated. The relative standard deviation (RSD) of experiments shows that the precision of test is obviously elevated on condition that the internal standard calibration is applied. Moreover, combined with the internal standard quantitative CO2-TPD-MS technique, the investigation on the catalytic performance of hydrotalcites in transesterification demonstrates that the solid base with the stronger alkalinity and the higher density of basic sites presents the higher catalytic activity.

Key words: solid base, CO2-TPD, hydrotalcite, density of basic sites, transesterification

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