Hydrolysis rate of aluminum nitride in a sodium hydroxide solution

Abstract

This paper describes a kinetic analysis of the hydrolysis of aluminum nitride (AlN) powder under highly alkaline conditions, in which the temperature dependence of the hydrolysis rate was measured to derive the most suitable kinetic reaction model. The hydrolysis reaction, AlN + NaOH + 3H 2O → NaAl(OH) 4(aq) + NH 3, AlN + OH- + 3H 2O → Al(OH) -4 + NH 3, was experimentally monitored by the aluminum ion concentration measured via Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) at different constant temperatures of 295, 300, 305, 310, 316, and 327 K. The reaction accelerated exponentially with solution temperature. The time required for the complete dissolution of the AlN samples was highly dependent on temperature; it was 1 ks at 327 K and 120 ks at 295 K. Based on a comparative analysis of various kinetic models, the reaction curves were most successfully simulated by a second-order homogeneous reaction with an activation energy of 69.2 kJ mol -1. Copyright © 2011 De Gruyter.