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