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OP-II-27non-flow type. During the MW heating of the catalyst, the vaporized reaction productswere directed to a condenser. The liquid as well as the gaseous (non-condensed)products have been analyzed by GLC method.During the experiments, we observe intense heating of the catalysts used, and itleads to boiling of hydrocarbons and formation of vaporized products. The productscomposition for all reagents used, as a rule, includes hydrogen, liquid and gaseous(C 2 H 4 , C 3 H 6 and CH 4 mainly) hydrocarbons which are lighter than the initial ones.The specific feature of the MW-assisted hexadecane pyrolysis is the predominantformation of α-olefins as the main products. Selectivity of the α-olefins formationexceeds 80% for the next catalysts: cermet, magnetocenospheres andPd/Fiberglass. In the presence of zeolite or fiberglass, the formation of alkanes ismore expressed. Note that all materials demonstrating high selectivity in respect tothe olefins formation are composites which include small metal particles. One cansuppose that under microwaves these catalysts are heated non-uniformly. Thepresence of small overheated particles promotes the α-olefins formation because ofthe olefins concentration must increase with the temperature rising. On the otherhand, this selectivity is additionally reinforced by the “quenching” effect. Indeed,alpha olefins are known to be the primary products of thermal decomposition of longalkane molecules. Under conditions of ordinary heating, these primary products maydecompose as a result of secondary reactions. On the contrary, under MW heating,the primary products of the thermal decomposition appear to be immediately incontact with the much colder liquid reagent, which provides their rapid cooling(quenching).Using a mathematical simulation, the model of the decomposition initiation in thevicinity of an individual MW-absorbing catalyst particle has been formulated andstudied. It is shown that there are some critical conditions of the reaction initiationdepending on the particles properties and parameters of the MW radiation. Themodel of the hydrocarbon decomposition in the vicinity of an individual MWabsorbingcatalyst particle allowing the effects of thermal expansion is considered.AcknowledgementsFinancial support from Russian Academy of Sciences under Project No.2 of the BasicResearch Program 19 is gratefully acknowledged. The work is also supported by SiberianBranch of Russian Academy of Sciences under Integration Ordered Project No.5.151