Traditional Rushton rigid impeller is often applied to gas-liquid dispersion process in industrial stirred tank reactors. However

poor gas dispersion capacity is occurred behind impeller blades due to easy formation of gas cavitation. In order to improve gas-liquid mixing performance

a rigid-flexible impeller was proposed to intensify gas dispersion process. Time series data of pressure fluctuation were recorded by LabVIEW and the largest Lyapunov exponent (LLE) was calculated by Matlab to analyze chaotic characteristics of gas-liquid mixing behavior

while relative power demand

total gas holdup

and local gas holdup were measured simultaneously in stirred tank with a rigid impeller or a rigid-flexible impeller. Results showed that

under condition of power consumption at 170 W and gas flowrate at 10 m3·h-1

rigid-flexible impeller could strengthen energy transfer and enhance chaotic mixing through rigid-flexible-flow interaction. LLE value of rigid-flexible impeller system was 8.89% higher than that of rigid impeller system. Rigid-flexible impeller could improve relative power demand

total gas holdup

local gas holdup

and more homogeneously gas dispersion

compared to rigid impeller at the same operating conditions.