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Two experimental methods, the Nile Red dye extraction and the Williamson ether synthesis in biphasic conditions, were used to characterize the mixing performance of a new cheap impinging jet colliding mixer from Gjosa and to compare it to other commercial micromixers (Caterpillar CPMM-R300, T-mixer, LTF MR-MX and LTF MR-MS). The Nile Red method shows that the Caterpillar mixer is the best one. Excellent results are also achieved with two Gjosa mixers in series. These results are not reflected in the Williamson ether synthesis, where the best mixer is the Gjosa one.

Catalytic reactions involving C–H bond activations are central to the chemical industry. One such example, alkane dehydrogenation, has recently become very important due to shortfalls in propene production and a large supply of cheap propane. However, current technologies are inefficient and have only moderate selectivity. In order to understand how to improve currently used catalysts, we must know more about the mechanism by which propane is dehydrogenated. We show here that Co(ii) sites on silica are good catalysts for the dehydrogenation of propane, having high activity and selectivity that is reasonably stable over the course of 10 h. Mechanistic investigations of this catalyst show that the main activation mechanism is most likely C–H activation by 1,2 addition.

Heterogeneous catalysis is essential for the transformation of light hydrocarbons into chemical feedstocks. Many of the catalysts that mediate these transformations consist of isolated metal ions on the surface of a metal oxide support, such as silica or alumina. Due to the complexity of these catalysts, studying the active site and mechanism of these reactions is difficult. Surface organometallic chemistry (SOMC) could offer a solution to this problem by allowing the synthesis of well-defined surface organometallic species. This approach has been used to study the reactions of light hydrocarbons with isolated metal species on silica and alumina surfaces. These studies showed that proton transfers play a key role in the reactions of many hydrocarbons. The mechanisms of these reactions and their role in some common catalytic cycles are discussed.