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• An apparent reaction rate model for heterogeneous medium-rate system was established. • The accuracy of the model was experimentally verified in a standard stirred tank reactor. • According to the prediction of the model, the mass transfer coefficient matching the intrinsic reaction kinetics was identified. • A rotor-stator homogenizer and a rotating packed bed reactor realized the matching of mass transfer and intrinsic kinetics for 1,1,2-trichloroethane dehydrochlorination reaction. The apparent rate of heterogeneous medium-rate reaction is jointly controlled by liquid-liquid mass transfer performance and intrinsic kinetics. Realizing the matching of them can significantly enhance the efficiency of the reaction. Here, the dehydrochlorination reaction of 1,1,2-trichloroethane with NaOH solution is used as an example to investigate the matching relation between intrinsic kinetics and mass transfer efficiency of medium-rate reactions. Firstly, an apparent reaction model considering mass transfer performance, intrinsic kinetics and physical properties of the system was established. The accuracy of the model was experimentally verified in a standard stirred tank. Based on the model, the mass transfer coefficient matching the intrinsic reaction kinetics at 51 ℃ should beyond 100 s−1, which requires to be achieved in mass transfer intensification reactors instead of conventional stirred tank. Therefore, a rotor-stator homogenizer and a rotating packed bed were used. The experimental results in these two reactors well demonstrated the model prediction. [ABSTRACT FROM AUTHOR]

• A model for the chemical deacidification process of crude oil was developed. • The model quantitatively revealed the effect of mass transfer on deacidification. • The rotating packed bed was firstly used to enhance this process with good effect. • The deacidification time was reduced from tens of minutes to 1 s in this work. Chemical deacidification is a key process for vegetable oil refining, but its efficiency is limited by the liquid–liquid mass transfer performance of reaction system. Here, a mathematical model containing mass transfer and reactions for the chemical deacidification process was developed at first. The modeling results quantitatively revealed the effect of mass transfer on deacidification efficiency and deacidification reaction time. Then, rotating packed bed (RPB) reactor was firstly applied to enhance the chemical deacidification due to its excellent heterogonous mass transfer performance. The effect of different operating conditions on the deacidification efficiency was systematically investigated. Under the optimal conditions, 99.85% deacidification efficiency was obtained after continuous treatment by RPB reactor. Comparing with traditional stirred tank reactor, the reaction time was reduced from tens of minutes to less than 1 s in RPB. Meanwhile excess alkali consumption was avoided. This work demonstrates an efficient and promising technique for vegetable oil refining. [ABSTRACT FROM AUTHOR]

• 112TCE and NaOH reaction kinetics was studied by simulation and experiment. • The conductometry and substrate concentration amplification method were first used. • The kinetic parameters of three parallel reactions were decoupled. • Kinetic parameters of overall and parallel reactions were obtained. Dehydrochlorination of 1,1,2-trichloroethane (112TCE) is a widely used method for preparing vinylidene chloride (VDC), which is an important polymeric monomer and intermediate of refrigerant. However, there are few reports on kinetics of this reaction system. In this work, density functional theory (DFT) calculation analyses and experiments were conducted to investigate the reaction mechanism and kinetics of 112TCE dehydrochlorination with sodium hydroxide (NaOH). DFT simulation results unveiled there were three parallel reactions which produce VDC, cis -1,2-dichloroethylene (C12DE) and trans -1,2-dichloroethylene (T12DE) respectively in the reaction process of 112TCE and NaOH. The activation energy of the reaction to produce VDC was lower than those of the other two reactions. Moreover, the kinetic parameters of the three parallel reactions, such as reaction orders, rate constants, pre-exponential factors and activation energies, were experimentally obtained by decoupling the overall reaction kinetics. All the parallel reactions are bimolecular elimination reactions and the rate expression of the intrinsic kinetics for generating VDC is d C t dt = 1.668 × 10 11 e - 75662 RT C A C B. The reaction rate is three orders of magnitude higher than those of producing C12DE and T12DE, which is consistent with the DFT simulation results. These kinetics results are useful for the process optimization and reactor design in VDC production process. [ABSTRACT FROM AUTHOR]