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The solubility, volumetric mass transfer coefficient, gas−liquid interfacial area, mass transfer coefficient, gas holdup, and bubble Sauter mean diameter for O2 and N2 in liquid cyclohexane were obtained in 4-L gas-inducing and surface-aerated agitated reactors. The modified Peng−Robinson equation of state and the transient gas absorption and photographic techniques were employed. The experiments were statistically designed and the results were statistically correlated with a 95% confidence level. The solubilities for O2 and N2 showed an increase with pressure and temperature, and Henry's law adequately modeled the values. All mass transfer parameters obtained were found to be higher in the gas-inducing than those in the surface-aerated reactor. Mixing speed and liquid height significantly affected the volumetric mass transfer coefficients and gas holdup in both reactors. The pressure and temperature slightly affected the volumetric mass transfer coefficients whereas the bubbles Sauter mean diameter for both gases remained constant at about 0.76 mm.

A statistical approach was developed to investigate the effects of pressure, temperature, mixing speed and solid concentration on kLu for gaseous hydrogen, ethylene, and propylene in liquid n-hexane containing solid polypropylene powder in a 4-litre agitated reactor. The solubilities of the gases appeared to follow Henry's Law. Statistical correlations to predict kLu were proposed and response surfaces were constructed. kLu values appeared to reach a maximum around 15 mass% and sharply decrease above 30 mass%. The effects of pressure and temperature on kLu were found to depend on the gas-liquid system and operating conditions used.On a m i s au point une mtthode statistique pour ttudier les effets de la pression, de la temphahue, de la vitesse de mtlange et de la concentration de solides sur kLu pour de I'hydrogkne, de I'ethylkne et du propylkne gazeux dans du n-hexane contenant de la poudre de polypropyltne solide dans un rkacteur agitk de 4 litres. Il semble que les solubilitks des gaz suivent la loi d'Henry. On propose des corrtlations statistiques d i n de pr6dire k,a, et des surfaces de reponse sont construites. Les valeurs de kLu semblent atteindre un maximum autour de 15% en masse et diminuent considerablement autour de 30% en masse. On a trouvt que les effets de la pression et de la temp6rature sur kLa dependaient du syst&me gaz-liquide et des conditions de fonctionnement utilisks.

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