use of Mg in the extraction of Titanium

• Ti can’t be extracted with carbon using a blast furnace because titanium carbide (TiC), which is very brittle, is formed rather than titanium
• Ti is extracted through the two step kroll process which is a batch process
• Kroll process:

  1. TiO2 (solid) is converted to TiCl4 (liquid) at 900 degrees celsius (high temp) TiO2 + 2Cl2 + 2C ——> TiCl4 + 2CO
  2. Mg or Na are used as a reducing agent to reduce TiCl4 to Ti TiCl4 + 2Mg ——> Ti + 2MgCl2 TiCl4 + 4Na ——> Ti + 4NaCl
• in the second step of the kroll process the Ti is reduced and Mg is oxidised
• the second step of the kroll process is done in an inert argon atmosphere which prevents the Mg or Na reacting with the oxygen from the air
• both reactions in the kroll process are exothermic helping to keep the reaction vessel at a very high temp, 900 degrees celsius