A comprehensive study on the kinetics, mass transfer and reaction engineering aspects of solvent-free glycerol hydrochlorination

The thorough kinetic study of the solvent-free hydrochlorination of glycerol using gaseous hydrogen chloride in a laboratory-scale semibatch reactor was carried out. A wide set of experiments was performed where reaction temperature (70-120 °C), catalyst concentration (0-50% by moles) and partial pressure (0.25, 0.5, 0.75 and 1.0 atm) were varied. Acetic acid was used as a homogenous catalyst. A more accurate approach was given to the semibatch reactor modeling since it was demonstrated that the liquid volume significantly increased along the reaction. The concentration of HCl was determined experimentally and it was possible to observe the influence of the reaction parameters on the HCl uptake. It was also evidenced that a non-catalytic hydrochlorination takes place in the system and its effect is non-negligible, especially at high temperatures. A new kinetic model was proposed and tested in order to explain the experimental observations. Non-linear regression analysis was successfully applied on the experimental data and the modeling results showed a satisfactory agreement. The model was able to estimate the activation energies for both catalyzed and non-catalyzed experiments. A new concept named Catalyst Modulus was derived from the kinetic equations and then verified with experimental data; the fit of this parameter was very high, thus, pointing out the validity of the model.