Radio-frequency inductively coupled plasma-chemical installation for preparation of nanodispersed powders

Full text: The wide application of radio-frequency inductively coupled plasma (rf-ICP) is due to the following. Rf-ICPs are clean because these types of plasma do not use any electrode and, hence, are contamination free. Rf-ICPs are stable and can be used over a wide range of operating conditions. They have relatively large volumes and low plasma velocities, which result in complete melting of the solid materials in materials processing because of the longer residence time. The preciseness of the rf-ICPs is important in determining contamination effects (which inevitably occur because of electrode evaporation and nozzle ablation) on gas circuit breaker arcs as well as to predict plasma properties for all materials processing, and any gas or mixture of gases can be excited by the rf fields, so there is wide flexibility when choosing plasma gas(es) depending on the type of application [1].; The experimental plasma set-up used for the production of nanosized powders (carbides, carbon nano-structures (nanotubes, fullerenes), oxides, nitrides, catalysts, pigments, etc.) consists of a radio-frequency generator (maximum power 60 kW, frequency 1+30 MHz), a water-cooled quartz plasma-chemical reactor with inductor, raw powder and gas supply systems, a gas quenching device, heat exchangers and cloth filter for powder collection. Ar, N2, Ar+N2, air, air+O2, and Ar+H2 can be used as plasma-forming gases. The quenching gases are air, Ar, N2, and CO2. The raw powder is injected into the upper part of the plasma-chemical reactor. A chemical reaction is carried out in the reactor and after complete evaporation of the micron size powder, it enters the quenching device. After that, the nanosized product is captured by the heat exchangers and cloth filter