Commercial Application of Radio-Frequency Plasmas

Commercial Application of Radio-Frequency Plasmas 

In contrast to the study of chemical syntheses in low-pressure, microwave, plasma discharges, the studies of chemical syntheses in atmospheric pressure, thermal plasmas have not given rise to any chemical compound that cannot be prepared by other techniques. The use of thermal plasma discharges does, however, offer a unique source of energized gas available at higher temperatures than normal chemical flames or other, indirect, electric heating techniques. 

Thorpe and Scammon (52) reported the first successful operation of a high-power, low-frequency induced plasma torch. They operated a 1-MW torch on argon at 450 kHz, producing a plasma of some 10 cm in diameter. Recently, Thorpe 51) reported the successful operation of an induced plasma at the still lower frequencies of 10 and 1 kHz. 

The operation of induced plasma devices at line frequency (50 Hz) is the ultimate objective of development work on torch scale-up, and Dundas 19) recently published data predicting operating powers and torch diameters for low-frequency plasma. The expected power requirement for a line frequency-induced plasma torch is circa 15 MW, and the achievement of this will clearly require considerable time and expenditure. 

These experiments suggest that the factors affecting the yields from plasma reactors are not always the most obvious ones, and much remains to be learned about the molecular processes that occur. The difficulties involved in the study of kinetics and thermodynamics of chemical reactions in high-temperature plasma tails are formidable, but even a crude understanding might permit a degree of control over plasma reactors that does not at present exist. 

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C. Decomposition VIII. Commercial Application of Radio-Frequency Plasmas... 

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