Method and apparatus for determining boiling points of liquids

DETAILED DESCRIPTION OF THE SPECIFIC CONSTRUCTION AND OPERATION OF A PREFERRED EMBODIMENT System Construction As illustrated in FIG.
3, a vessel 8 capable of withstanding pressure forms a chamber 10 that is filled with a liquid sample 12 for which the boiling point curve is to be determined.
The bubble cauldron described in the concurrently filed application could provide a suitable chamber.
A vacuum pump 14 may be used to evacuate the chamber 10 prior to filling it from a liquid reservoir 16 through a valve 18 in order to avoid dissolved atmospheric gases in the liquid sample 12.
A whirligig hot spot thermocouple 30 is disposed within the chamber 10, and a small bubble detection transducer 32 is placed in the vicinity of the whirligig hot spot thermocouple 30.
The chamber 10 may be connected to a pressure pump 34 for varying the pressure in the chamber.
The pressure pump 34 may be similar to one disclosed in the concurrently filed application.
The chamber 10 may be placed upon a heatable and coolable base 36 used for controlling the ambient temperature of the liquid sample 12 in the container 10.
The pressure pump 34, heater and cooler base 36, transducer 32, and whirligig hot spot thermocouple 30 all provide inputs to a microprocessor 50.
FIGS.
4A and B illustrate a preferred construction of the whirligig hot spot thermocouple 30.
A non-conducting body 100, which may be made of plastic and comprised of an upper section 102 and a lower section 104, provides for holding securely four pairs of insulated lead wires 106-1, 106-2, 108-1, 108-2, 110-1, 110-2, 112-1 and 112-2 as shown in the FIGS.
4A and B.
The lead wires 106, 108, 110, 112 may be held securely by providing passages from the top face of the upper portion 102 through the upper portion and through the lower portion 104, the passages in the upper portion 102 and lower portion 104 being displaced from each other when the portions are joined together as shown particularly in FIG.
4B.
The portions may be held together by four screws 114 and the lower portion may be provided with a flange 116 tapped for securing to another surface by a screw 118