from chemical reactions such as reaction enthalpy,
adiabatic temperature rise, and activation energy are essential for
reaction safety and scale-up from laboratory investigations to reactor
design and operation. Typically, these data are gained from batch
calorimeters with sophisticated setups and elaborate measurement procedures.
Continuous flow calorimeters, compared with batch setups, have different
mixing and heat transfer characteristics and enable harsh reaction
conditions, particularly within microstructured reactors with their
enhanced heat transfer capability. This review provides an overview
of currently investigated and applied flow calorimeters in research
and development in relation to existing concepts. Novel approaches
for heat flux measurements as well as integrated sensors are presented.
Safety aspects of flow chemistry are a main driver, but additionally,
low material consumption is important in early process development.
Limitations of the concepts are presented with a comprehensive literature
overview of flow calorimetry to show that continuous flow calorimeters
form a new tool in process development and safety engineering, particularly
with microstructured devices and novel sensing techniques.