(181a) Use of DFT Calculation and Experimental Data to Model Heat of Reaction

The environmental and process safety engineering group (EPSE) at Merck evaluates the process safety of Merck projects globally. A primary purpose of these assessments is the evaluation of safety implications for reaction streams or materials for all scales from the lab to the pilot plant and through manufacturing and supply. One key topic of concern is assessment of the thermal and pressure hazards of chemical processes, including determination of heat of reaction of the desired chemistry. One of the testing strategies we use to investigate the heat of reaction is heat flow or isothermal calorimetry. However, calorimetry cannot always be employed due to issues such as toxicity, potency of compounds and in some cases lack of materials. Recently, we have been looking into leveraging an estimation of heat of reaction data via computational methods to supplement existing experimental methods. We will describe the thought process, some initial data, and potential of the computational data to enhance our existing heat of reaction estimation capability. Techniques investigated include Density functional theory (DFT) calculation, CHETAH and simpler heat of formation estimation. Case studies will be discussed as part of this presentation.