Characterization of cinchonidine doped montmorillonite supported noble metal catalysts by thermoanalytical methods

The characterization of new cinchonidine doped K-10 montmorillonite support ed noble metal catalysts is described. Our aim was the mapping of thermal s tability of these new catalytic materials by thermogravimetry (TG), differe ntial thermogravimetry (DTG) and differential thermoanalysis (DTA) methods accompanied by X-ray diffraction (XRD) measurements. The catalysts were prepared by various methods including conventional, micr owave and ultrasonic treatments. They were characterized first by X-ray dif fraction to verify the stability of montmorillonite crystal structure durin g preparation. Then, TG and DTG methods were applied to determine their sta bility under the experimental conditions usually applied. The main changes observed were the loss of water and the decomposition of the organic modifi ers in the higher temperature region. The catalyst showed the best performa nce were prepared and characterized using microwaves and ultrasonic irradia tion in order to get more insight to the effect of preparation methods on t heir stability. As a consequence, the catalysts were found to be stable and regenerable under 450-500 K, however, higher temperatures resulted in the complete destruction of the catalysts.