Binary mixture tests reduction

The tests with the three formulations gave similar steady-state friction coefficient of about 0.12. So, the binary additive combination did not provide any friction reduction. However, friction fluctuations were significantly decreased when using the binary mixture. This smoothing effect on the friction luis already been observed in the literature when h-BN powder was added in a base oil [7]. 

To better address the role of Pt in the reduction mechanism, a physical mixture of the binary Pt/y-Al203 and BaAy-A O, samples was also prepared and tested. This catalytic system is constituted by all the components of the reference ternary system, even if in the physical mixture Pt and Ba are deposited on different alumina particles [44],... 

To darify better the role of Pt in the reduction mechanism, a physical mixture of the binary Pt/Y-Al2O3 (1 100 w/w) and Ba/Y-Al2O3 (20 100 w/w) samples was prepared and tested [117]. Also in this case NO was stored at 350 °C upon adsorption of NO in the presence of excess O2 [102], then the stability/reactivity of stored nitrates was investigated by means of TPD and H2 TPSR. The TPD data showed that decomposition of adsorbed nitrates occurs at temperatures very dose to that of adsorption the presence of H2 (TPSR run) does not decrease significantly the temperature threshold for nitrate decomposition (which is still observed near 350 °C), but instead provokes the reduction of the evolved NO to NH3 and N2. Hence the previously invoked Pt-catalyzed route is active only when Pt and Ba are dispersed over the same particle of the support. 

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