General and Prospective Views on Oxidation Reactions in Heterogeneous Catalysis

Abstract

In this short review paper we have assembled the main characteristics of partial oxidation reactions (oxidative dehydrogenation and selective oxidation to olefins or oxygenates, as aldehydes and carboxylic acids and nitriles), as well as total oxidation, particularly for depollution, environmental issues and wastewater treatments. Both gas-solid and liquid-solid media have been considered with recent and representative examples within these fields. We have also discussed about their potential and prospective industrial applications. Particular attention has been brought to new raw materials stemming from biomass and to liquid-solid catalysts cases. This review paper also summarizes the progresses made in the use of unconventional activation methods for performing oxidation reactions, highlighting the synergy of these technologies with heterogeneous catalysis. Focus has been centered on usual catalysts activation methods but also on less usual ones, such as the use of ultrasounds, microwaves, grinding (mechanochemistry) and photo-activated processes, as well as their combined use.

Ultrasonic–biogenic synthesis of silver on anodized aluminum with superior antibacterial properties

“…35 In fact, high ultrasonic radiation (20 kHz) creates local heating effects from cavitation (formation, growth, and collapse of bubbles) to assist the nucleation and growth of biogenic Ag-NPs. 36,37 According to the theory of hot-spot mechanism, implosion of cavities (resulting from both high local temperature and cooling rate of 5000-25 000 K and 410 11 K s À1 , respectively), following the ultra-sonic process, leading to an increased and faster chemical reaction rate. 35 The average size of biogenic Ag-NPs was B58 AE 25 nm (ESI, † can be found in Fig.…”