An Improved Adiabatic Titration Calorimeter

The complexity and cost of instrumentation that has been necessary to provide the ability to measure the complete temperature profile of a chemical reaction without heat loss has been sizeably reduced in the improved adiabatic titration calorimeter that is described. Its design is such that even large changes in temperature during reaction can be accommodated without transfer of heat into or out of the calorimeter. This is accomplished simply by matching such changes in the calorimeter temperature by simultaneous and equivalent changes in the temperature of a surrounding water bath. This capability of the calorimeter eliminates the special instrumentation that is required in other calorimeters to measure the small temperature change that can be tolerated without significant loss of heat. The titrant is stored in a glass coil in thermal contact with the solution in the calorimeter prior to its controlled transfer into the solution by displacement with air. By this approach the heat capacity of the calorimeter is essentially unchanged during calorimetric study of a reaction. This simplification removes the need for repetitive calibration inherent in the operation of other calorimeters.