IR spectroscopic investigation of hydrodechlorination on Pt-containing zeolites Original Research Article

Two PtY-FAU zeolite samples, prepared by impregnation and ion exchange methods, and a Pt ion exchanged ZSM-5 zeolite sample reduced with two methods were studied in hydrodechlorination reactions. The generation of acid sites was investigated by IR spectroscopy after pyridine adsorption. Hydrodechlorination of CCl4 resulted CH4 and CHCl3 as main products besides HCl. With increasing temperature the hydrodechlorination of CHCl3 also took place. For CHClF2 no hydrodechlorination was observed at under identical experimental conditions. For trichloroethene (TCE) and tetrachloroethane (TCA) the product distribution corresponded to a hydrodechlorination reaction giving ethane and HCl as the main products. In spite of the hydrogen atmosphere under hydrodechlorination conditions side reactions occurred on Pt-containing zeolites with high Brønsted acidity, small amount of oxygen-containing product, phosgene was formed with the participation of the framework oxygen of the zeolite.