Abstract
The reaction between SiO(g) and CO(g) is a relevant intermediate reaction in the silicon production process. One of the products generated from this gas mixture is called by its color, brown condensate. In this paper, SiO(g) and CO(g) are produced from SiO2-SiC pellets. The reaction between the two gases occurred on SiC particles. Inert gas was injected at different flows. The SiC particles were collected, and the brown condensate deposited on them was characterized by electron probe microanalysis, X-ray photoelectron spectroscopy, and focused ion beam preparation samples for transmission electron microscope analysis. The brown condensate consists of a mixture of Si spheres embedded in a SiO2 matrix. The compound generates in the temperature range from 1400 °C to 1780 °C (1673 K to 2053 K), and in the SiO(g) partial pressure range between 0.534 and 0.742, depending on the inert gas flow. SiC crystallites are located at the Si-SiO2 interface. Carbides are believed to generate from the reaction between liquid silicon and CO(g). Carbides may also precipitate from reaction between dissolved carbon and liquid silicon, but to a minor extent. Both mechanisms are believed to happen above the melting point of silicon and in the softening range of silica.
Highlights
METALLURGICAL silicon is produced by the reduction of silica by carbonaceous materials in electric arc furnaces
transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) analyses are the novelty of the current work
A weak signal comes from the spheres, a mild one is detected at the interface, and a strong response is located in the rest of the system
Summary
METALLURGICAL silicon is produced by the reduction of silica by carbonaceous materials in electric arc furnaces. These two compounds are the main intermediate species in silicon production As this gas mixture is entering the low-temperature area in the furnace (1300 K to 2000 K), it will generate condensates and SiC according to Reactions [1 through 3][1,2,3,4]: 2SiOðgÞ ! SiO(g) and SiC contribute to the formation of silicon in the inner high-temperature zone (2100 K to 2400 K),[5] by Reaction [4]. The mixture generated from Reaction [2] is referred to as white condensate This compound will not be the main focus of this paper. The compound generated through Reaction [1] is called brown condensate This crust is often found in industrial excavations, but it has never been characterized thoroughly.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
