Calorimetric studies of the heats of formation of IIIB-VB adamantine phases

Thermodynamic assessment of the Al–P system based on original experimental data

“…All experimental investigations found in the literature on thermodynamic properties and phase equilibrium data of the binary Al-P 900-1200 0-0.005 [42] Solubility of P in liquid Al Controlled high temperature filtration experiments 690-1000 0-0.0007 [43] system are collected in Table 2 [14,35,[37][38][39][40][41][42][43]. The standard enthalpy of formation of AlP, Δ f H1(AlP), was experimentally measured by several researchers independently [14,35,37,38].…”

“…The standard enthalpy of formation of AlP, Δ f H1(AlP), was experimentally measured by several researchers independently [14,35,37,38]. In the following the originally reported data are cited, the data converted to SI units and proper reference states are given in Table 3.…”

“…In the following the originally reported data are cited, the data converted to SI units and proper reference states are given in Table 3. This is considered necessary because when these data were cited in the later studies [5,6,9,44,37,38], they were confused by the reference states and units. Wang et al [35] used an oxygen bomb calorimeter and obtained the heat of formation of AlP phase as À 2972 kcal mol À 1 by subtracting the heat of combustion of AlP from the heat of combustion of the aluminum powder and red phosphorus mixture.…”

“…If the reference state were red phosphorus, then this Δ f H1(AlP) value would be even more negative. The most convincing study was published by Martosudirdjo and Pratt [37]. By measuring the heat of precipitating AlP compound from Sn bath in a precipitation calorimeter, they obtained the enthalpy of formation of AlP as À17.68470.205 kcal mol-atoms À 1 at 309 1C from 12 measurements and they reported the Δ f H1 value of À 17.41 kcal mol-atoms À 1 with red phosphorus and fcc aluminum as reference states.…”

“…Coefficients A n and B in Eq. (4) were then determined by accepting the experimental result of the enthalpy of formation [37], thus fixing A n , and optimizing the value of B to by using the experimental vapor pressure data [41]. The liquid phase interaction parameters A L and B L were optimized based on the experimental data of Lescuyer et al [43] for the solubility of P in liquid Al.…”