A modular 3D printed isothermal heat flow calorimeter for reaction calorimetry in continuous flow

Utilization of highly reactive compounds in novel flow syntheses requires new tools for process development. This work presents such a tool in the form of a modular calorimeter designed for direct heat flux measurements in continuous flow applications. The calorimeter consists mainly of 3D printed parts, which can be adapted and reassembled easily to meet user-defined applications. By utilizing selective laser melting (SLM) of stainless steel and digital light processing (DLP) of a UV curable resin, a device is produced to meet the requirements of handling highly reactive organic compounds. Calorimeter segments are temperature-regulated independently of each other by a microcontroller, allowing isothermal operation conditions. Direct heat flux measurements are possible in the device through Seebeck elements which are calibrated internally at prevailing process conditions with the aid of heating foils. Functionality of the designed calorimeter is shown by good agreement of conducted heat flux measurements with literature.