Micron-sized silicon carbide particle production via rapid unloading of high-pressure liquid CO2

We describe a novel methodology for micron-sized silicon carbide particle production via rapid unloading of high-pressure liquid CO2. The method is based on the physical characteristics of liquid CO2 such as low viscosity, high permeability, and a high dilation coefficient. A series of silicon carbide powdering experiments were performed. The overall process includes water saturation, water and silicon carbide filling, pressure initialization, CO2 filling, high pressure initialization, and CO2 gasification, which is a completely physical process. After high-pressure penetration and CO2 gasification expansion, the silicon carbide will immediately be converted into micron-sized particles. Most importantly, this method is much more effective than the most popular method of SiC synthesis (Acheson method). Laser grain size analysis indicates that the grain size of the silicon carbide particles ranges between 30 and 50 μm, and the percent grain size less than 176.9 μm accounts for 90%. The rapid unloading of high-pressure liquid CO2 method is much more environmentally friendly, efficient, energy saving, and effective.