Pure Appl. Chem., Vol. 74, No. 3, pp. 413–418, 2002. © 2002 IUPAC 413 Plasma-assisted production of hydrogen from hydrocarbons* Maxim Deminsky ‡ , Victor Jivotov, Boris Potapkin, and Vladimir Rusanov RRC “Kurchatov Institute”, Kurchatov Square, Moscow, 123182, Russia Abstract: This paper is dedicated to the discussion of possible plasma applications for hydro- gen-rich gas production from hydrocarbons. Different types of plasma, both thermal and nonequilibrium ones, are under consideration. A special attention is devoted to experimental and theoretical results on hydrocarbon conversion in nonequilibrium plasma of pulse microwave discharge. A comparison of plasma methods and conventional catalytic technol- ogy is presented as well. INTRODUCTION Currently, industrial demand for hydrogen and hydrogen-rich gas is continuously growing. This is related first of all with hydrogen energy concept development in energy production and transportation. Conventional catalytic technology, essentially in the case of small- and moderate-scale portable appli- cations, has certain problems because of relatively low specific productivity, high metal capacity, and equipment size. Even thermal plasma, being very high energy density media, is giving an attractive alternative for hydrogen and syngas production. In this approach, plasma replaces catalysis and accel- erates chemical reactions mainly because of high temperature effect. The advantages of plasma chem- ical methods are extremely high specific productivity of apparatus, low investment, and operation costs. However, relatively high electric energy consumption applies certain restrictions on possible applica- tions of thermal plasma approach. Nonthermal plasma can accelerate chemical reactions at the low tem- perature as well owing to active species generation by fast electrons. If active species, generated by non- thermal plasma, are capable of promoting many cycles of chemical transformation then high specific productivity of plasma can be combined with low energy consumption of traditional catalysts. That is why this so-called plasma catalysis approach has generated permanent, strong interest in recent decades. Some hydrocarbon (HC) conversion processes and, in particular, methane decomposition into hydrogen and carbon black, are endothermic reactions, and to cover process enthalpy and to shift chem- ical equilibrium to hydrogen and carbon, reagents should be heated in any case. Nevertheless, the tem- perature level required to shift chemical equilibrium is relatively low (600–1000 K), and one can use for the process relatively low potential heat while plasma will be applied only as a catalytic agent for active species generation. THERMAL PLASMA APPLICATION FOR HYDROGEN PRODUCTION One of the main problems of hydrocarbon conversion processes, from a chemical point of view, is kinetic limitation. Low rates of processes (see Fig. 1) give the only possibility for application of con- *Lecture presented at the 15 th International Symposium on Plasma Chemistry, Orléans, France, 9–13 July 2001. Other presenta- tions are presented in this issue, pp. 317–492. ‡ Corresponding author