Fast Response Heating Module for Temperature Programmed GC Analysis in Microreaction Systems

Abstract

For monitoring the reactant and product concentrations of a gas phase microreactor for ethylene oxide synthesis the development of a miniaturised device for fast GC analysis suitable for operation in conjunction with the microreactor is advantageous. Therefore, a method employing short (0.2 – 0.4 m) packed capillary columns was developed. Highly crosslinked polystyrene microspheres proved to be the most suitable adsorbent enabling a high separation efficiency. For fast temperature programming design concepts for an efficient heating module capable to be used with short capillary columns were developed. In principle, planar as well as cylindrical designs are suitable for integration of a resistive heating device, cooling microchannels and structures to accommodate a short GC capillary column. First experiments using a planar prototype module show that 10 to 15 times higher heating rates can be achieved compared to a standard GC oven, thus, leading to a 6-fold decrease in retention time. Further improvement employing a cylindrical design is deduced from simulation results.