Gaseous SO3 is used as the sulfonating agent to design a gas-liquid micro-sulfonation system for the synthesis of dodecylbenzene sulfonic acid(DBSA).The interaction between the factors is analyzed according to the response surface method.The gas-liquid two-phase flow pattern accompanied with sulfonation reaction within the microchannel is characterized through a high-speed camera,and the liquid film thickness is also measured.The effect of turbulence on mass transfer is evaluated through turbulent diffusion coefficient,accordingly the liquid-phase mass transfer coefficient and Hatta number are calculated.Results demonstrate that the gas-liquid two-phase flow pattern accompanied with reaction within the microchannel shows a wavy annular flow,with an average liquid film thickness in the range of 90-160 μm.The higher liquid-phase flow rate enhances the turbulent diffusion coefficient,thereby increasing the mass transfer coefficient.Concurrently,the mass transfer coefficient will significantly decline as the conversion rate of dodecylbenzene(DDB)increases,suggesting that as the reaction progresses,particularly during the later stages,the reaction products will severely hinder the mass transfer process.Additionally,the calculated Hatta number results indicate that all Hatta values are greater than 3,signifying that the sulfonation reaction within the microchannel remains a rapid,diffusion-controlled reaction.
关键词
微通道/气液磺化/传质特性/气液两相流型/十二烷基苯磺酸
Key words
microchannel/gas-liquid sulfonation/mass transfer characteristics/gas-liquid two-phase flow pattern/dodecylbenzene sulfonic acid
维普
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