Heterogene Gasphasenkatalyse im Mikrowellenfeld

A New Reactor for Combined Conventional and Microwave Heating

“…Further, the application of energy occurs over all the volume of the dielectric material to be heated. Moreover, a targeted heating of a catalytic site or substance seems to be possible due to the selective interaction of the microwaves [3].…”

Nonthermal Effects of Microwaves in Organic Synthesis

“…At the macroscopic level because it is essential when strong MW-absorbing solid catalysts are involved, for example, graphite [54] or Magtrieve (an oxidant) [55] where the (high) temperatures are not homogeneously distributed. However, some controversy also exists about the effects of MW irradiation in heterogeneous catalysis because modification of the catalyst's electronic properties, and even structures, has been proposed [56]. 3) Decrease in the activation energy G = is certainly the main effect.…”

Microwave Theory

“…The non-absorbing components are thus not heated directly, but only by heat transfer from the heated component. For heterogeneous mixtures, in particular for gas/solid systems involving heterogeneous gasphase catalysis [37,38] the sometimes observed rate enhancements and changes in selectivities have been attributed to the formation of localized (macroscopic) hot spots having temperatures of 100-150 C above the measured bulk temperature [39]. The measurement and estimation of temperature distributions induced by microwave heating in solid materials is, however, very difficult.…”