Effect of heat treatment on the formation of copper active centers obtained by the interaction of copper chloride with H-mordenite

The effect of temperature conditions on the formation of copper active sites obtained by solid state ion exchange between copper chloride and H-mordenite zeolite using X-ray absorption spectroscopy in near-threshold (XANES) and extended (EXAFS) spectral regions behind the copper $K$-edge measured in in-situ conditions of the reaction at temperatures varying from room temperature to 400$^\circ$C. The analysis of the spectra performed using direct calculations of CuK-XANES and taking into account anharmonic corrections for CuK-EXAFS fitting enables us to establish that there is no ion exchange up to 200$^\circ$C and copper remains in the CuCl state. An increase in the temperature higher 200$^\circ$C leads to the incorporation of copper atoms to the zeolite framework.