Carbochlorination of dispersed oxides in a molten salt reactor

Reaction mechanism and rates were determined from 803 to 1,073 K for the carbochlorination of Al 2 O 3 and of Al, Si and Fe‐mixed oxides using Cl 2 and C slurried in a stirred melt of NaCl—AlCl 3 . Alumina chlorination rates of 0.33–2.0 × 10 −8 kmol/s were obtained using C:melt weight ratios between 1:21 and 1:42. The reaction rate was proportional to C loading at temperatures below 923 K, while gas‐liquid mass transfer was rate‐controlling at higher temperatures. Carbochlorination of the combined oxides in coal fly ash at 923 K and oxide conversions less than about 50% was also gas‐liquid mass‐transfer‐controlled. At higher conversions, dissolution became the rate‐controlling factor. A 40% (molar) AlCl 3 melt was more effective than a 48% AlCl 3 melt for the selective chlorination of Al 2 O 3 over SiO 2 .