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Abstract  

The aim of this work is basically centred in the improvement of the obtention of the peroxides precursors of macrocyclic lactones (C11 and C16) through the Story synthesis useful as raw materials for high performance linear polyesters. As a starting point, the yield has been increased respect to the classic synthesis using mild and intrinsically safer reactants. Concretely, a yield of 55% in triperoxide of cyclohexanone has been achieved using 35% hydrogen peroxide and phosphotungstic acid as catalyser. For this intention two factorial experimental designs, fractional and complete, have been carried out. The analytical method adequate for the reactive system studied (HPLC-UV-RI) has been chosen as well as the optimal operating conditions. A quantification of the risk on the first part of the reaction in calorimetric terms has been performed.

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Journal of Thermal Analysis and Calorimetry
Authors: R. Nomen, M. Bartra, J. Sempere, E. Serra, J. Sales, and X. Romero

Summary  

Estimation methods developed over years by S. W. Benson and co-workers for calculation the thermodynamic properties of organic compounds in the gas phase are applied to a pharmaceutical real process with all type of non-idealities. The different strategies used to calculate the reaction enthalpy of a chemical process, in the absence of data for complex molecules, using the Benson group additivity method are presented and also compared with the experimental value of reaction enthalpy obtained using reaction calorimetry (Mettler-Toledo, RC1). We demonstrate that there are some strategies that can be followed to obtain a good estimation of the reaction enthalpy in order to begin the safety assessment of a chemical reaction. This work is part of an industrial project [1] in which the main objective was the risk assessment of chemical real and complex processes using the commonly available tools for the SMEs (with limited resources).

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