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Microbubbles were applied for the first time to enhance the aqueous biphasic hydroformylation of long‐chain alkenes. The gas–liquid–liquid multiphase hydroformylation was carried out using 1‐dodecene as model higher olefin and dihexadecyl dimethyl ammonium bromide (DDAB) as surfactant. The increasing liquid temperature resulted in the increased mean bubble size and total bubble number, but this trend became inapparent at high temperatures due to the reduced liquid viscosity. The increasing gas flow rate was favorable to increase the multiphase interfacial area, thus leading to the increasing mass transfer coefficient KLa. The conversion of 1‐dodecene reached maximum 95% in the three‐phase microemulsion system, and at a gas flow rate of 40 ml min−1. Further increasing the gas flow rate to 80 ml min−1 decreased the conversion, which was attributed to the destroyed flow field, as observed in micro‐PIV. Owing to the increased multiphase mass transfer efficiency, the application of microbubbles allowed to intensify the hydroformylation reaction with reduced reaction pressure, higher chemoselectivity, and increased turnover frequency (TOF). [ABSTRACT FROM AUTHOR]

To study the three-dimensional motion characteristics of bubbles in a bubble slurry bed, a simultaneous measurement method for bubble size and velocity based on a light field imaging particle tracking velocimetry (PTV) technology was proposed. A light-field PTV bubble measurement system was constructed, the light-field camera was used to collect two consecutive light field images. After refocusing calculation, image processing and sharpness evaluation, the size and three-dimensional coordinates of the bubbles were calculated combined with the calibration results. The PTV technology was used to calculate the three-dimensional velocity of the bubble, and the simultaneous measurement of bubble size and three-dimensional velocity was completed. The evaluation of the light field PTV system and the measurement of bubble size and three-dimensional velocity were carried out. The results show that the relative error of the diameter measurement is less than 1.60%, the repeatability error of the diameter measurement is less than 2. 48%, and the relative error of the depth position measurement is less than 7.14% . When the air flow increases from 0.1 L/min to 0.5 L/min, the average equivalent diameter of the bubbles increases from 3. 85 mm to 4. 36 mm, and the average bubble velocity increases from 0. 34 m/s to 0. 38 m/s. The light field imaging PTV technology can be used for simultaneous measurement of the bubble size and the three-dimensional velocity. [ABSTRACT FROM AUTHOR]