Improvement of process safety and efficiency of grignard reactions by real-time monitoring

Grignard reactions possess considerable hazard potentials due to the spontaneous heat release during the initiation of these strongly exothermic reactions and the high reactivity of the Grignard compounds. To establish an industrially applicable method for an objective real-time detection of the reaction start-up and for the accumulation of the organic halide during the process, a heat/ mass balance-based real-time monitoring approach was developed and tested by miniplant experiments. In addition to the concentration profiles provided by the approach, the real-time estimation of the safety-relevant parameters, such as adiabatic temperature rises and corresponding pressures, enables application of advanced control strategies up to the point of a safety-oriented, fully automated control of Grignard reactions. At the same time, such systems can contribute to improved process efficiency by increasing the space-time yield as well as enhancing the inherent safety of the process.