Fig. 1. A standard BGR TECH calorimeter with stirring devices for calorimetric reactions vessels
Fig. 1 presents a typical BGR TECH
calorimeter. As it is seen in Fig. 1 it can be used over the temperature
range from 303 K to 673 K. It has built-in liquid and dry air coolers.
Thus, with an additional external cooling thermostat and a dry air flushing
the temperature range can be lowered down to at least 223 K. The calorimeter
is a versatile instrument with two symmetric entries to the calorimetric
detectors, upper and bottom, what permits to adapt experimental vessels
to investigation of various processes with the simultaneous use of additional
detectors, such as spectroscopic, pH or other, and assure an efficient
stirring of the content of the vessels with a step-wise or continuous
dosing of reactants. Also, the sensitivity can be easily adapted to the
requirement of the processes under investigation, ranging from tenths
of microwatt up to a few hundreds of miliwatts. Especially for test experiments
an automatic selection of the calorimetric sensitivity and its automatic
change, if needed, during the course of the experiment is also possible.
Special experimental vessels containing internal bellows and a special
sensitive device for the recording of the bellows displacement are offered
for simultaneous measurements of isobaric heat capacity and thermal expansion
of liquid systems over large temperature intervals under pressures up
to 20 MPa without any controlling high pressure pump.