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This work presented experimental and modeling studies on the simultaneous absorption of H2S and CO2 into the N-methyldiethanolamine (MDEA) and piperazine (PZ) solution in a rotating packed bed (RPB). The effect of different operating conditions, including MDEA concentration (C MDEA), PZ concentration (C PZ), liquid volumetric flow rate (L), temperature (T), and high gravity factor (β) on the absorption efficiencies of H2S and CO2 (ηH2S and ηCO2 ) were investigated. The results showed that ηH2S and ηCO2 were significantly affected by C MDEA, C PZ, L, and β. ηH2S and ηCO2 could reach 99.98 and 96.51%, respectively. Furthermore, an artificial neural network (ANN) model was established to predict ηH2S, ηCO2 , and mass-transfer coefficient (K G a). Results showed that the predicted values were in good agreement with the experimental values (within deviations of ±10% for H2S and CO2). This work provides a potential technology of simultaneous absorption of H2S and CO2 for the biogas upgrade.

Liquid flow behaviors in the packing zone of a rotating packed bed reactor significantly affect the mass transfer performance. However, the interaction between the rotating packing and liquid is still not clear, due to packing's complex structure. In this work, liquid jet impaction on a rotating single-layer wire mesh was investigated to clarify the interaction and liquid flow behaviors after the impaction was observed and analyzed by visualization and simulation methods. Visual experiments showed that the interaction could be divided into the shearing action generated by vertical fibers and carrying action generated by horizontal fibers of wire mesh. A dimensionless number β was introduced as a criterion to evaluate the influence of these actions on the liquid dispersion. Simulation results agreed well with the experimental results of liquid dispersion. Dynamic liquid film behaviors on the fiber surface were further simulated and the average film thickness was 21-32 μm.

A novel rotating packed bed (RPB) reactor is first adopted to intensify the reaction of isobutane alkylation with 2-butene catalyzed by H2SO4. This work investigated reaction performance, and reaction conditions were optimized. Under the optimal conditions, the research octane number (RON) reached 98.85. Meanwhile, the yields of C8 and trimethylpentanes were 90.65% and 85.47%, respectively. The reaction efficiency was tremendously improved by using RPB due to its high efficiencies of mass transfer and micromixing. More importantly, the inner mole ratio of isobutane to 2-butene was dramatically decreased in RPB, which means the energy cost of material cycling in the alkylation process could be extremely reduced. Moreover, an empirical correlation model was proposed to predict the multiproduct yields and RON with a deviation within ±10%. In conclusion, RPB reactor is a highly promising industrial platform for the process of H2SO4 alkylation.

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