A microfluidic strategy for accessing the thermal conductivity of liquids at different temperatures

Rosa Moreno Jimenez (1, 2) , Benoit Creton (1) , Claire Marliere (1) , Lionel Teule-gay (2) , Olivier Nguyen (2) , Samuel Marre (2)

1 IFPEN - IFP Energies nouvelles
2 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux

Biomass-based biofuels represent a promising alternative fossil energy source, for which conversion processes - mostly performed at high pressure and temperature conditions - require thermophysical property data, particularly thermal conductivity. Conventional methods to measure thermal conductivity are often time consuming and/or need important quantities of products. Microfluidics has been proven to be a viable solution to these issues thanks to its low reagent consumption, fast screening capabilities, improvement of heat and mass transfers etc. However, microfabrication materials used in previous works, do not exhibit sufficient chemical inertness, nor thermomechanical properties to apply such methods to large ranges of fluids systems and conditions. Here, we develop new microreactors including sensors integrated into microfluidic channels with an operating principle based on the transient thermal offset approach for thermal conductivity measurement, built with materials commonly used for microreactors operated in harsh conditions. The sensor calibration is performed on water/ethanol mixtures and externally validated for two fluids: n-pentadecane and ethan-1,2-diol along with the evolution of their thermal conductivity with temperature. Finally, the microfluidic device is used to generate thermal conductivity data for 2,5-dimethylfuran, a biomass-based compound with high potential as biofuel and for which experimental data has not been reported so far.

Mots clés: Micro-sensor; Microfluidics; Thermal conductivity; Temperature

Domaines: Génie chimique; Matériaux

Rosa Moreno Jimenez, Benoit Creton, Claire Marliere, Lionel Teule-gay, Olivier Nguyen, et al.. A microfluidic strategy for accessing the thermal conductivity of liquids at different temperatures. Microchemical Journal, 2023, 193, pp.109030. ⟨10.1016/j.microc.2023.109030⟩. ⟨hal-04155254⟩