Plasma assisted decomposition

Hsiao, M.C., Merritt, B.T., Penetrante, B.M. et al. (1995) Plasma-assisted decomposition of methanol and trichloroethylene in atmospheric pressure air streams by electrical discharge processing, J. Appl. Phys. 78, 3451-6. 

The objective of plasma-assisted decomposition of hydrocarbons is to produce hydrogen and carbon in an oxidant-free environment (as opposed to plasma-assisted POx and steam reforming that produce hydrogen and C02), according to the following generic reaction ... 

Thermal plasma-assisted decomposition (cracking) of heavy hydrocarbons is reported in Ref. 141. Decomposition of paraffinic hydrocarbons including C16H34 by Ar-H2 plasma was carried out by continuous injection of the hydrocarbon in the spouted-bed reactor. Controlling temperature, residence time, and H2 concentration allows reaching the... 

A large class of coordination compounds, metal chelates, is represented in relation to microwave treatment by a relatively small number of reported data, mainly p-diketonates. Thus, volatile copper) II) acetylacetonate was used for the preparation of copper thin films in Ar — H2 atmosphere at ambient temperature by microwave plasma-enhanced chemical vapor deposition (CVD) [735a]. The formed pure copper films with a resistance of 2 3 pS2 cm were deposited on Si substrates. It is noted that oxygen atoms were never detected in the deposited material since Cu — O intramolecular bonds are totally broken by microwave plasma-assisted decomposition of the copper complex. Another acetylacetonate, Zr(acac)4, was prepared from its hydrate Zr(acac)4 10H2O by microwave dehydration of the latter [726]. It is shown [704] that microwave treatment is an effective dehydration technique for various compounds and materials. Use of microwave irradiation in the synthesis of some transition metal phthalocyanines is reported in Sec. 5.1.1. Their relatives - porphyrins - were also obtained in this way [735b]. 

In another paper, the authors advocated a plasma-assisted decomposition of methane into hydrogen and carbon.13 It was estimated that 1-1.9 kWh of electrical energy is consumed per normal cubic meter of hydrogen produced. The authors stated that plasma production of hydrogen is free of C02 emissions. However, since most of the electric energy supply in the world comes from fossil fuels, electricity-driven hydrogen production processes such as plasma and electrochemical processes, are C02 producers. 

Alternatively to decomposition of silane/hydrocarbon-mixtures hydrogenated amorphous Sii xCx films can be deposited from the gas phase by conventional pyrolysis, photolysis or plasma assisted decomposition of various small hydridocarbosilanes. The composition and therefore the properties of the films are known to be affected by the conditions of the... 

Thermal decomposition of MesAs (on a GaAs surface) and EtjjAsH, (n>0-3) have been studied absorption and decomposition of EtjAsH on silicon (100) surfaces have been Investigated by electron energy loss spectroscopy. Photolysis and plasma-assisted decomposition of MejAs have also attracted attention, as have the thermolyses of RjSb (R>Me, Pr, CHj-CH and CH =CHCH2). 

In general, several possible chemical reactions can occur in a CVD process, some of which are thermal decomposition (or pyrolysis), reduction, hydrolysis, oxidation, carburization, nitridization and polymerization. All of these can be activated by numerous methods such as thermal, plasma assisted, laser, photoassisted, rapid thermal processing assisted, and focussed ion or electron beams. Correspondingly, the CVD processes are termed, thermal CVD, plasma assisted CVD, laser CVD and so on. Among these, thermal and plasma assisted CVD techniques are widely used, although polymer CVD by other techniques has been reported. ... 

Roh, H. S. Park, Y. K. and Park, S. E. Superior decomposition of NO over Plasma-assisted catalytic system induced by microwave Chem. Lett., 2000, 578-579... 

Further insight into the mechanism of plasma-assisted catalysis can be gained by studying the temperature dependence of the oxidation process and comparing the decomposition of the DCM as a frmction of temperature for both plasma catalysis and thermal catalysis The catalyst is incorporated into the barium titanate packed-bed plasma reactor in a one-stage configrrration. The reactor can be heated to 400°C with an electric heater. Figure 6.6 shows the temperature variation for the decomposition of DCM with a catalyst. 

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