AbstractInterfacial areas and gas hold‐ups were determined at pressures of up to 1.7 MPa in a glass vessel, 88 mm in diameter and of standard geometry. Superficial gas velocities between 0.25 and 2.0 cm/s were used and the stirring speed varied between 4 and 30 rps. The interfacial areas were determined by the chemical method, using the model reaction between CO2and aqueous diethanolamine (DEA). Hold‐ups were determined by observation of differences in height. In contrast to literature indications, the gas hold‐up was found to be independent of reactor pressure. This is also true for the interfacial