F
Reaction Calorimetry
F.1
Basic Aspects of Calorimetry
As introduced in Chap. 8, calorimetry is an experimental technique that can be used
to characterize the heat released or absorbed by a system from a chemical reaction.
First established in the eighteenth century, it can be described using the simplified
heat balance previously introduced in Sect. 8.2:
˙
q acc = ˙
q r − ˙
q c
(F.1)
• ˙
q acc : rate of heat accumulation
• ˙
q r : rate of heat released by the reaction
• ˙
q c : rate of heat exchanged with the surroundings (cooling)
One of the fundamental aspects that distinguish the different calorimetric
methods that exist is the mode applied for temperature control. Three of the common
operating modes are:
• Adiabatic: the temperature increase results from the released heat of reaction—
allows for the determination of the thermal runaway curve.
• Isothermal: the temperature of the sample is kept constant—allows for the
determination of the conversion term of the reaction rate.
• Dynamic: the temperature of the sample is varied linearly over a specified
temperature range—allows for the determination of the enthalpies of reaction.
In the case of an adiabatic calorimeter, the heat balance can be simplified as:
˙
q acc = ˙
q r
( ˙
q c = 0)
(F.2)
© The Author(s), under exclusive license to Springer Nature Switzerland AG 2021
K. Hungerbühler et al., Chemical Products and Processes,
https://doi.org/10.1007/978-3-030-62422-4
297
Reaction Calorimetry
F.1
Basic Aspects of Calorimetry
As introduced in Chap. 8, calorimetry is an experimental technique that can be used
to characterize the heat released or absorbed by a system from a chemical reaction.
First established in the eighteenth century, it can be described using the simplified
heat balance previously introduced in Sect. 8.2:
˙
q acc = ˙
q r − ˙
q c
(F.1)
• ˙
q acc : rate of heat accumulation
• ˙
q r : rate of heat released by the reaction
• ˙
q c : rate of heat exchanged with the surroundings (cooling)
One of the fundamental aspects that distinguish the different calorimetric
methods that exist is the mode applied for temperature control. Three of the common
operating modes are:
• Adiabatic: the temperature increase results from the released heat of reaction—
allows for the determination of the thermal runaway curve.
• Isothermal: the temperature of the sample is kept constant—allows for the
determination of the conversion term of the reaction rate.
• Dynamic: the temperature of the sample is varied linearly over a specified
temperature range—allows for the determination of the enthalpies of reaction.
In the case of an adiabatic calorimeter, the heat balance can be simplified as:
˙
q acc = ˙
q r
( ˙
q c = 0)
(F.2)
© The Author(s), under exclusive license to Springer Nature Switzerland AG 2021
K. Hungerbühler et al., Chemical Products and Processes,
https://doi.org/10.1007/978-3-030-62422-4
297