Open Accessμ FlowCal – High‐Resolution Differential Flow Microcalorimeter for the Measurement of Heats of Mixing
Author(s) -
Vaz Inês C. M.,
Torres Manuel C.,
Silva Fernando M. T.,
Carpinteiro. Francisco S.,
Santos Luís M. N. B. F.
Publication year - 2022
Publication title -
chemistry ‐ methods
Language(s) - English
Resource type - Journals
ISSN - 2628-9725
DOI - 10.1002/cmtd.202100099
Subject(s) - isothermal process , thermodynamics , chemistry , enthalpy , differential scanning calorimetry , refrigerant , micromixer , mixing (physics) , entropy of mixing , dilution , analytical chemistry (journal) , chromatography , microfluidics , heat exchanger , physics , quantum mechanics
This work presents the description, calibration, test and performance evaluation of a new flow microcalorimeter. The μ FlowCal is a differential heat conduction, flow microcalorimeter, designed to work in isothermal conditions, in differential mode and in the absence of gas phase, requiring small amounts of sample (200 μL). Both the microcalorimeter and its operational methodology were optimized to measure the heat of mixing of fluids with moderate viscosity and volatility. The microcalorimeter has a sensitivity of 116 μV mW −1 and a level of detection of 170 nW. A very good performance (uncertainty <5 %) was obtained for the selected test processes: enthalpy of dilution of aqueous sucrose solutions and excess enthalpy of binary mixtures of decane‐octanol. The μ FlowCal prototype is a new tool in micro‐scale physical chemistry and a step forward concerning signal resolution and sample volume. Nowadays, these are major requirement for the study of novel promising solvents and their mixtures.