ACID AND CATALYTIC PROPERTIES OF MNOM-ZRO2 (M = CA, BA, SM, YB) COMPOSITIONS

Influence of the nature of MnOm in zirconia-based systems MnOm-ZrO2 (M = Ca, Ba, Sm, Yb) of approximately equimolar composition on their aci d and catalytic properties in oxidative conversion of methane (OCM) ha ve been studied. The surface of MnOm-ZrO2 systems has been found to co ntain practically no Bronsted acid sites. Lewis acid sites are represe nted by three types of L-sites, their total concentration per m(2) dec reasing in the series (Zr, Ca)O-2 > (Zr, Sm)O-2 > (Zr, Yb)O-2. Activit y of the catalysts in the OCM reaction is proportional to the specific surface area. Their selectivity to Sigma C-2 hydrocarbons increases i n the series (Zr, Ca)O-2 < (Zr, Sm)O-2 < (Zr, Yb)O-2.