Combining Isothermal and Adiabatic Mode Experiments for Kinetic Constant Estimation: Application to the Hydrogenation of 5-(Hydroxymethyl)furfural (5-HMF)

Abstract

In the vast majority, kinetic modeling is done under isothermal conditions. The benefit of the adiabatic mode is using temperature as an online observable. Nevertheless, in the adiabatic mode, one can only get the initial/inlet and final/outlet concentrations, making the development of kinetic models difficult in the presence of several reaction steps. Obtaining kinetic models tested in isothermal and adiabatic modes could change our methodology in kinetic modeling because such models can be used in optimization, thermal risk assessment, and pinch analysis. Besides, for chemical systems with several reaction steps, one needs to spend much time analyzing the different samples to get concentration profiles. Thus, developing kinetic models combining isothermal and adiabatic experimental runs could reduce the experimental stage. We tested this methodology in the hydrogenation of 5-(hydroxymethyl)furfural (5-HMF) by using different combinations of adiabatic and isothermal noised synthetic runs. We compared the estimated kinetic constants obtained from these noised synthetic runs with the hypothetical true ones and the sum of squared residuals. The hypothetical true kinetic constants were created. Global sensitivity analysis using the hypothetical true kinetic constants in isothermal and adiabatic modes was carried out to measure the influence of these constants on the estimated concentration and temperature. We found that implementing some adiabatic runs in a set of experimental runs could be beneficial from a parameter estimation standpoint.