Plasma arc pyrolysis

Plasma arc pyrolysis Involves passing an — Short start-up and shutdown times, electric current through a low-pressure increasing safety, 

Chemical Weapons/Explosive Waste/Unexploded Ordnance 

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Plasma arc pyrolysis 2007 to 2011 Plasma Energy Applied Technology. Inc., Huntsville. Ala. 

Another recent report describes the large scale synthesis of ahgned carbon nanotubes, of uniform length and diameter, by passage of acetylene over iron nanoparticles embedded in mesoporous silica [107]. The latter two methods, based on the pyrolysis of organic precursors over templated/catalysts supports, are by far superior by comparison with plasma arcs, since other graphitic structures such as polyhedral particles, encapsulated particles and amorphous carbon are notably absent (Fig. 16). 

Tsang, W. (1994) Incineration, pyrolysis and plasma arcs for destruction of toxic waste at high temperatures ", Paper at the NATO-Advanced Research Workshop on Destruction of Military Toxic Waste, Naaldwijk, The Netherlands, May 22-27. 

IGC, inert gas condensation plasma, arc, RF, or thermal LP, laser pyrolysis LA, laser ablation SP spray pyrolysis IS, ion sputtering. 

Biomedical. Heart-valve parts are fabricated from pyrolytic carbon, which is compatible with living tissue. Such parts are produced by high temperature pyrolysis of gases such as methane. Other potential biomedical apphcations are dental implants and other prostheses where a seal between the implant and the living biological surface is essential. Plasma and arc-wire sprayed coatings are used on prosthetic devices, eg, hip implants, to achieve better bone/tissue attachments (see Prosthetic and BiOLffiDiCALdevices). 

The preparation of CNTs is a prerequisite step for the further study and application of CNTs. Considerable efforts have been made to synthesize high quality CNTs since then-discovery in 1991. Numerous methods have been developed for the preparation of CNTs such as arc discharge, laser vaporization, pyrolysis, and plasma-enhanced or thermal chemical vapor deposition (CVD). Among these methods, arc discharge, laser vaporization, and chemical vapor deposition are the main techniques used to produce CNTs. 

Based on the preceding discussion, it appears clear that the PAHs observed by arcing graphite electrodes in hexane are derived from solvent pyrolysis in the plasma ball of the arc while the polyynes are released by the graphite electrodes. Since polyynes are also considered the precursors of... 

A number of arc reactors and plasma jets have been described for the electrocracking of liquid hydrocarbon fractions from petroleum distillation. Because of higher content of unsaturated hydrocarbons and the absence of 02, CO and C02, plasma pyrolysis is preferred over oxidative pyrolysis. 

Both the electric arc and the plasma jet have been used for the pyrolysis of coal. Acetylene is the principal hydrocarbon product, its yield being three times more in a hydrogen atmosphere than in an argon atmosphere. Since the thermodynamic stability of acetylene decreases rapidly below about 1600 K, the product gases must be quenched rapidly in order to prevent the decomposition of acetylene (Sect. 2). 

In general, processes generating low-molecular carbon clusters in an arc or plasma have to be distinguished from such with thermal processes like combustion or pyrolysis supplying the building blocks for fuUerene growth. The most important variants of both basic forms are discussed below. 

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