IUPAC-NIST Solubilities Database

IUPAC-NIST Solubility Database
NIST Standard Reference Database 106

Solubility System: Pyrene with n-Heptane and 1-Propanol

Components:
   (1) 1-Propanol; C3H8O; [71-23-8]  NIST Chemistry WebBook for detail
   (2) n-Heptane; C7H16; [142-82-5]  NIST Chemistry WebBook for detail
   (3) Pyrene; C16H10; [129-00-0]  NIST Chemistry WebBook for detail

Original Measurements:
   Zvaignze, A.I.; Acree, W.E., Jr., J. Chem. Eng. Data 1993, 38, 393-395.

Variables:
   Temperature = 299 K

Prepared By:
   W.E. Acree, Jr. and A.I. Zvaigzne

Experimental Data:   (Notes on the Nomenclature)


t/°C	Mole Fraction x₁	Mole Fraction x₃	x₃s
26.0	0.01102	0.0000	0.0000
26.0	0.01154	0.1905	0.1927
26.0	0.01089	0.3244	0.3280
26.0	0.00916	0.5548	0.5599
26.0	0.00814	0.6602	0.6656
26.0	0.00734	0.7329	0.7383
26.0	0.00568	0.8760	0.8810
26.0	0.00495	0.9369	0.9416
26.0	0.00426	0.9957	1.0000

Notes:
     x₃^(s): initial mole fraction of binary solvent mixture; x₁: mole fraction solubility of the solute; x₃: mole fraction of component 3 in the ternary solution.

Method/Apparatus/Procedure:
   Constant temperature bath, calorimetric thermometer, and an ultraviolet/visible spectrophotometer.
Binary solvent mixtures were prepared by weight. Excess solute and solvent placed in amber glass bottles and allowed to equilibrate for several days at constant temperature. Attainment of equilibrium was verified by several repetitive measurements and by approaching equilibrium from supersaturation. Aliquots of saturated solutions transferred through a coarse filter into tared volumetric flasks, weighed and diluted with methanol. Concentrations determined spectrophotometrically at 372 nm.

Source and Purity of Materials:
   (1) 99 %, Aldrich Chemical Company, Milwaukee, Wisconsin, USA, recrystallized 3 times from absolute ethanol.
   (2) HPLC Grade, 99.7+ %, Aldrich Chemical Company.
   (3) 99+ %, anhydrous, Aldrich Chemical Company. Components 2 and 3 were stored over molecular sieves and distilled shortly before use.

Estimated Errors:

   Temperature: T/K: ± 0.05. x₃^(s): ± 0.0001. x₁: 1.5 % (relative error).