Study on thermodynamics and kinetics for the reaction of aluminum hydride and water by microcalorimetry

Abstract

An exothermic reaction between aluminum hydride (AlH3) and water was observed in our laboratory. The reaction process of AlH3 and water was studied using a microcalorimeter. The results show that the reaction enthalpies of AlH3 with water and the enthalpies of formation of AlH3 at T = (313.15, 318.15, 323.15, 328.15) K are (−405.10, −405.56, −406.02 and −406.48) kJ mol−1, and (−10.81, −10.59, −10.36, −10.13) kJ mol−1, respectively. The standard enthalpy of formation and standard molar heat capacity of AlH3 obtained by an extrapolation method are −11.49 kJ mol−1 and 45.22 J mol−1 K−1, respectively. The values of activation energy E, pre-exponential factor A and the reaction order n for the reaction of AlH3 and water over the temperature range from 313.15 to 328.15 K are 69.41 kJ mol−1, 108.46 s−1 and about 1.033, respectively.