It has beenfound that the reaction rate between alumina and carbon in nitrogen can be considerably increased by using AI(OH)3-C mixtures instead ofll. in the starting mixtures should be greater than the stoichiometric ratio to complete the reaction. It was observed that alumina is reduced and nitrided to form aluminium nitride via spinel type aluminium oxynitride which is an intermediate compound. The overall reaction rate increased with decreasing AI(OH)3particle size and increasing nitrogenjlowrate.It is thought that thefaster reaction rates obtainedfrom AI(OH)3-C mixtures were derivedfrom the high specific surface area of transition aluminas, such as y A1 2 0 3 , whichformed during heating of the samples to the reaction temperature. The particle morphologies of the Al (0 H) 3 powders did not change during the reduction and nitridation reaction, an important attribute to the process.MSTj1346c

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