The effect of mixing of miscible liquids with disparate viscosity in co-axial flow on chemical reactions*

Achieving optimal process results in mixing limited – fast reactions is a long-standing challenge in chemical industry. For complex reactions with multiple desirable and undesirable products, solutions to optimizing the product yield could lead to inefficiencies, such as reducing productivity, increasing solvent/dilution or reduced catalyst activity and so on. Providing improvements to mixing in such systems becomes further complicated if there are large viscosity differences between the reacting fluids.

This talk will discuss the effect of disparate viscosity fluid mixing on fast chemical reactions in co-axial jets. High fidelity experiments and numerical simulations show that the viscosity ratio between the two reacting streams lead to significant differences in mixing and therefore in resultant chemical species. A novel in-line spectrometry technique has been developed and validated to measure the resultant chemical species in the product stream. Numerical modeling of chemical reactions is based on the Li &Toor [Li & Toor, AIChE J, 32(8)1986] approach. The comparison of the numerical modeling to the experimental data highlight the importance of mixing on pH and therefore on the chemical kinetics.