A KEY TO PROGRESS - IDENTIFICATION OF THE STATE OF CATALYSTS DURING THE CATALYTIC REACTION

We stress the importance of identifying the state in which catalysts a re during the catalytic reaction. Catalysts as prepared do not corresp ond to the real working catalyst. Several examples will be recalled, a nd a new one (Mo-Te-O catalyst) will be mentioned. in a more detailed way, it will be shown that the working state of MoO3 is MoxO3x-2 with 8 less than or equal to x less than or equal to 18. The pitfalls encou ntered when focusing on catalysts as prepared (as opposed to catalysts ''as they work'') is illustrated in the case of mixed SbxMoyOz oxides which decompose spontaneously during the reaction.