Hydrogenation of 2-ethylanthraquinone is a key step in the industrial production of hydrogen peroxide via anthraquinone. This reaction on palladium-supported catalysts is normally carried out in trickle-bed reactors. ...Hydrogenation of 2-ethylanthraquinone is a key step in the industrial production of hydrogen peroxide via anthraquinone. This reaction on palladium-supported catalysts is normally carried out in trickle-bed reactors. A numerical model for simulation of a gas-liquid-solid hydrogenation trickle-bed reactor is presented. The model is based on the film theory and takes into account the axial dispersion effect on the performance of the reactor. Comparison of calculated values with data from pilot plant and industrial reactor shows that the agreement is quite satisfactory and the maximum variance is less than 5%. Gas-liquid and liquid-solid mass-transfer coefficients are determined by semi-empirical correlations available in the literature. The palladium-supported catalyst is extremely active and the reaction is always controlled by gas-liquid mass-transfer, and the overall effectiveness factor is always very low in agreement with the high catalytic activity of the palladium-supported catalyst.The overall effectiveness factor increases with decreasing catalyst hold-up. Therefore, it is feasible to improve the productivity of unit catalyst by decreasing the catalyst hold-up in a commercial plant with the hydrodynamic characters kept unchange.展开更多
For the gas and liquid superficial velocity ranging from 0.07—0.36?m·s -1 and 0.008—0.016?m·s -1 respectively,the significance of operating conditions on the macro-characteristic properties,such as liquid ...For the gas and liquid superficial velocity ranging from 0.07—0.36?m·s -1 and 0.008—0.016?m·s -1 respectively,the significance of operating conditions on the macro-characteristic properties,such as liquid holdup,pressure drop,pulsing velocity and pulsing frequency etc ,are investigated through experiments.Based on the 130 dynamic liquid holdup data a new correlation is proposed for the dynamic liquid holdup as: β d=1.324· γ·Re l 0.057 ·Re g -0.332 ,and correlation of the pressure drop is shown as: Δ p Δ L=∑iA i(1-ε) 2a 2 vε 3μ iu i+B i(1-ε)a vε 3ρ iu 2 i ,where A l=3.84×10 -3 ,A g =9.33×10 -3 ,B l=7.0×10 -5 ,B g =1.59×10 -4 .A new type of corcentric ring conductance probe was used to measure the conductance fluctuation in the trickle bed reactor packed with 4—5?mm glass beads.The pulse velocity and frequency are calculated based on the time series data.Correlations of the pulse velocity and pulse frequency were obtained as V p =1.575u g 1.98 1-0.0864u g 12.01 (1-17.668U l)and f= -2.505 +5.113U g +2.04×10 2U l,respectively.All the correlations have high accuracy in predicting the parameters.展开更多
The macro-kinetics of diphenyl carbonate synthesis was studied over Pd-Cu/La0.5Pb0.5MnO3 catalyst in a trickle-bed reactor.The catalyst particle size was φ2.0 mm×3 mm.A power type macro-kinetic model was employe...The macro-kinetics of diphenyl carbonate synthesis was studied over Pd-Cu/La0.5Pb0.5MnO3 catalyst in a trickle-bed reactor.The catalyst particle size was φ2.0 mm×3 mm.A power type macro-kinetic model was employed in the present study.The model parameters-were regressed-in the kinetics.The statistic test and its residual error distribution have been made,respectively.The results show that the values calculated by power type macro-kinetic models can be good agreement with experimental data.Furthermore,the model can provide the theory basis on simulation and design of the large scale synthesis of diphenyl carbonate in trickle-bed reactor.展开更多
基金国家重点基础研究发展规划项目 (No 2 0 0 0 0 480 0 5 )国家自然科学基金项目 (No 2 0 10 60 11)化学工程国家重点实验室资助~~
文摘Hydrogenation of 2-ethylanthraquinone is a key step in the industrial production of hydrogen peroxide via anthraquinone. This reaction on palladium-supported catalysts is normally carried out in trickle-bed reactors. A numerical model for simulation of a gas-liquid-solid hydrogenation trickle-bed reactor is presented. The model is based on the film theory and takes into account the axial dispersion effect on the performance of the reactor. Comparison of calculated values with data from pilot plant and industrial reactor shows that the agreement is quite satisfactory and the maximum variance is less than 5%. Gas-liquid and liquid-solid mass-transfer coefficients are determined by semi-empirical correlations available in the literature. The palladium-supported catalyst is extremely active and the reaction is always controlled by gas-liquid mass-transfer, and the overall effectiveness factor is always very low in agreement with the high catalytic activity of the palladium-supported catalyst.The overall effectiveness factor increases with decreasing catalyst hold-up. Therefore, it is feasible to improve the productivity of unit catalyst by decreasing the catalyst hold-up in a commercial plant with the hydrodynamic characters kept unchange.
文摘For the gas and liquid superficial velocity ranging from 0.07—0.36?m·s -1 and 0.008—0.016?m·s -1 respectively,the significance of operating conditions on the macro-characteristic properties,such as liquid holdup,pressure drop,pulsing velocity and pulsing frequency etc ,are investigated through experiments.Based on the 130 dynamic liquid holdup data a new correlation is proposed for the dynamic liquid holdup as: β d=1.324· γ·Re l 0.057 ·Re g -0.332 ,and correlation of the pressure drop is shown as: Δ p Δ L=∑iA i(1-ε) 2a 2 vε 3μ iu i+B i(1-ε)a vε 3ρ iu 2 i ,where A l=3.84×10 -3 ,A g =9.33×10 -3 ,B l=7.0×10 -5 ,B g =1.59×10 -4 .A new type of corcentric ring conductance probe was used to measure the conductance fluctuation in the trickle bed reactor packed with 4—5?mm glass beads.The pulse velocity and frequency are calculated based on the time series data.Correlations of the pulse velocity and pulse frequency were obtained as V p =1.575u g 1.98 1-0.0864u g 12.01 (1-17.668U l)and f= -2.505 +5.113U g +2.04×10 2U l,respectively.All the correlations have high accuracy in predicting the parameters.
文摘The macro-kinetics of diphenyl carbonate synthesis was studied over Pd-Cu/La0.5Pb0.5MnO3 catalyst in a trickle-bed reactor.The catalyst particle size was φ2.0 mm×3 mm.A power type macro-kinetic model was employed in the present study.The model parameters-were regressed-in the kinetics.The statistic test and its residual error distribution have been made,respectively.The results show that the values calculated by power type macro-kinetic models can be good agreement with experimental data.Furthermore,the model can provide the theory basis on simulation and design of the large scale synthesis of diphenyl carbonate in trickle-bed reactor.
