I&EC 312

Chemical micro processing can both improve current chemical processes and act as an enabling technology towards novel chemistry. Recently, microstructured reactors step into chemical production and thus micro-reactor process and plant design, including economic incentives, is the issue at this time. The potential of using microstructured reactors and their plants with exemplary new process developments.

The formation of ionic liquids often uses reaction paths which comprise at least one feature which render reactions tailored for use in microstructured reactors – large heat releases which may result in impurity formation, if heat transfer is insufficient.

The aim of the performed investigations was to obtain some generic relationships between heat release with connected temperature profile (hot spot formation)in a reactor set-up for continuous and solvent-free ionic-liquid synthesis. For this purpose, a typical micromixer-tube reactor (1/16 inch or 1/8 inch) embedded in a thermostated bath was equipped with seven temperature sensing elements distributed over the length of the tube. Total flow rate was varied from 100 to 400 ml/h and temperature between 30°C to 60°C. Hot spot formation up to 100°C was observed especially for the higher bath temperatures. Using two tube-reactor sections with smaller internal diameter (1/16 inch) in advance to other larger-sized sections resulted in better temperature control, which demonstrates the multi-scale reactor concept.