Advanced Arc Plasma Synthesis of Biomorphic Silicon Carbide Using Charcoal and Silicon Dioxide in Air

Abstract

The paper presents the results of experimental studies on the advanced synthesis method for a cubic phase of silicon carbide using charcoal and silicon dioxide as precursors. The charcoal used for the synthesis was obtained by steam pyrolysis of wood wastes (sawdust). It was found that the arc synthesis could be executed in air due to the protective CO and CO 2 environment formation by charcoal oxidation. With an increase of the amount of supplied energy by direct current arc plasma synthesis, the products of two crystalline phases were formed: graphite and cubic phase of silicon carbide. The phase of silicon carbide was extracted from the synthesis product by its annealing in air at 850 °C. The resulting cubic SiC phase was characterized by an elementary cell parameter of 4.359 Å. According to the data of scanning electron microscopy, the morphology of crystals obtained is common for the biomorphic silicon carbide which was identi ed in the synthesis product. The ceramics synthesized by spark plasma sintering from the obtained material was characterized by a density of ~2.0 g/cm 3 . Statement Of NoveltyFor the rst time the ceramics sample based on silicon carbide synthesized using biochar and silicon oxide via vacuumless electroarc method was obtained.

Red mud and foundry sand industry wastes for reducing NOx in plasma activated diesel exhaust

“…This led to the redesigning of plasma reactors with the intension of enhancing the energy in the charged species favoring reduction reactions instead of oxidation ones [9,10] but not without serious limitations with respect to the gas flow. On one hand, pure catalysts/adsorbents-based gas treatment techniques were becoming less efficient and more expensive, the plasma-alone was unable to reduce the gaseous pollutants to the desired level, on the other hand [11][12][13][14][15][16][17][18][19][20]. At this juncture, the plasma supported catalysts/adsorbents showed improved results in the gas treatment at laboratory environment [21,22].…”