Reactive Mass Transfer around Isolated Bubbles Rising in a Thin-Gap Cell

The reactive mass transfer around isolated bubbles of pure oxygen rising in a thin-gap cell filled with acetonitrile at rest is investigated. A colorimetric technique based on the bio-inspired copper(I) complex [Cu(TMG(2)tol)]OTf is used. The gap- and time-averaged dissolved oxygen concentration fields can be measured in the far-wake of the bubbles with 3 < d < 47 mm. The variations of the Sherwood numbers with the Peclet numbers indicate that the mass transfer results obtained are identical with the ones measured earlier with the copper(I) complex [Cu(btmgp)I]. This demonstrates the independency of mass transfer from the properties of the chemical system used. The results significantly enlarge the existing database, which is of great importance to establish robust scaling laws.