Hexadecane (C<sub>16</sub>H<sub>34</sub>) + 1-Hexadecanol (C<sub>16</sub>H<sub>33</sub>OH) Binary System:  Crystal Structures of the Components and Experimental Phase Diagram. Application to Thermal Protection of Liquids

V. Métivaud, Adeline Lefèvre, L. Ventolà, Philippe Négrier, Evelyn Moreno, Teresa Calvet, Denise Mondieig, M.A. Cuevas‐Diarte

Chemistry of Materials · 2005 · 43 citations · 35 references

Concepts

Abstract

The experimental temperature−composition phase diagram of the binary system between hexadecane (C 16 H 34 ) and 1-hexadecanol (C 16 H 33 OH) has been established by combining thermal analysis and powder X-ray diffraction (XRD). Beforehand, crystal structures of the solid ordered phases of the components involved were determined from XRD data. Hexadecane displays a triclinic form T p belonging to the space group P 1̄, with Z = 1. The unit cell dimensions are a = 4.269 Å, b = 4.811 Å, c = 22.34 Å, α = 84.54°, β = 67.43°, and γ = 73.00°. 1-Hexadecanol displays a monoclinic form γ belonging to the space group A 2/ a with Z = 8. The unit cell dimensions are a = 8.980 Å, b = 4.939 Å, c = 87.91 Å, and β = 122.63°. The phase diagram between both components is characterized by two invariants, a eutectic (located at T = 289.5 K) and a metatectic (located at T = 318.8 K). The miscibility in the solid state is very restricted, limited to the regions rich in C 16 H 34 and C 16 H 33 OH. Resulting alloys have led to the design of a double-wall glass for the thermal protection of liquid products between 13 and 18 °C, effective for 4.5 h in an external environmental temperature of 24 °C.

References

35