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RESISTANCE OF IMPINGING STREAM CONTACTOR TO SOLID-AIR SUSPENSION FLOW

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Chinese Journal of chemical engineering 1997年第3期5卷 82-91页

作者：吴高安伍沅 department of chemical engineering Wuhan Institute of Chemical Technology department of chemical engineering Zhejiang University of Technology

1 INTRODUCTIONAs mentioned in our previous paper impinging stream contactor(ISC)is aninnovative device for phase contact operations and has proved itself capable to en-hance transfer processes in heterogeneous systems effectively,and thus is of poten-tial application in many chemical engineering processes,such as drying of solidparticles,solid-solid,liquid-liquid and gas-gas mixing,absorption and desorptionof gases into or from liquids with or without chemical reactions,combustion

关键词： impinging streams resistance pressure drop contactor

Hydrothermal formation of dispersive Mg(OH)_2 particles in NaOH solution

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中国有色金属学会会刊：英文版 2004年第2期14卷 370-375页

作者：向兰金永成金涌 department of chemical engineering

The hydrothermal modification of Mg（OH）2 crystals in NaOH solution was investigated. The aggregated Mg（OH）2 particles with irregular shape are converted to regular Mg（OH）2 hexagonal plates after hydrothermal treatment. The prolongation of reaction time from 14 h or the increase of temperature from 140 ℃ to 200 ℃ can promote the formation of Mg（OH）2 plates with big particle size but small cluster size. The dispersion characteristics of the hydrothermal products are improved owing to the improvement of Mg（OH）2 crystalline degree and the increase of I)（001）)/I)（101）) ratio. The proper hydrothermal modification condition is as follows: solid content 0.075 g/mL, NaOH concentration 5.0 mol/L, temperature 200 ℃ and time 4 h. Thermodynamic analysis indicates that the increase of MgOH+ concentration at elevated temperature or the increase of OH- concentration in concentrated NaOH solution is favorable for the hydrothermal formation of Mg（OH）2 particles.

关键词：氢氧化镁氢氧化钠溶液水热合成分散结构

Synthesis,gas adsorption and reliable pore size estimation of zeolitic imidazolate framework-7 using CO_2 and water adsorption

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Chinese Journal of chemical engineering 2017年第5期25卷 595-601页

作者： Mahdi Niknam Shahrak Morteza Niknam Shahrak Akbar Shahsavand Nasser Khazeni Xiaofei Wu Shuguang Deng chemical engineering department Faculty of EngineeringQuchan University of Advanced Technology chemical engineering department Faculty of EngineeringFerdowsi University of Mashhad chemical engineering department New Mexico State University chemical engineering department Arizona State University

Reliable estimation of the pore size distribution(PSD) in porous materials such as metal–organic frameworks(MOFs) and zeolitic imidazolate frameworks(ZIFs) is crucial for accurately assessing adsorption capacity and corresponding selectivity. In this study, the so-called zeolitic imidazolate framework-7(ZIF-7) is successfully synthesized via relatively fast and convenient microwave technique. The morphology and structure of the obtained MOF were characterized by XRD, SEM and N_2 and CO_2adsorption/desorption isotherms at 77 K and0 °C respectively. Then, to determine the PSD of the fabricated MOF, carbon dioxide isotherms are experimentally measured at various temperatures up to atmospheric pressure. Afterward, the experimental CO_2 isotherms data are utilized in two recently proposed in-house algorithms of SHN1 and SHN2 to extract the true PSD of manufactured ZIF-7. The obtained results revealed that median pore diameter of the fabricated ZIF-7 is estimated around 0.404 nm and 0.370 nm by using CO_2 isotherms at 273 K and 298 K respectively. These values are in good agreement with the real pore diameter of 0.42 nm. Moreover, experimental data of water adsorption isotherms over four different MOFs, borrowed from literature, are employed to illustrate further effectiveness of the above algorithms on successful determination of the corresponding pore size distributions. All predicted PSDs are proved to be in good agreement with those obtained from independent methods such as topology and morphology studies.

关键词： ZIF-7 Metal–organic framework Size distribution Adsorption CO2 capture Gas

Experimental investigation and adaptive neural fuzzy inference system prediction of copper recovery from flotation tailings by acid leaching in a batch agitated tank

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International Journal of Minerals,Metallurgy and Materials 2019年第5期26卷 538-546页

作者： Jalil Pazhoohan Hossein Beiki Morteza EsfANDyari department of chemical engineering Quchan University of Technology department of chemical engineering University of Bojnord

The potential of copper recovery from flotation tailings was experimentally investigated using a laboratory-mixing tank. The experiments were performed with solid weight percentages of 30 wt%, 35 wt%, 40 wt% and 45 wt% in water. The measurements revealed that adding sulfuric acid all at once to the tank rapidly increased the efficiency of the leaching process, which was attributed to the rapid change in the acid concentration. The rate of iron dissolution from tailings was less than when the acid was added gradually. The sample with 40 wt% solid is recommended as an appropriate feed for the recovery of copper. The adaptive neural fuzzy system(ANFIS) was also used to predict the copper recovery from flotation tailings. The back-propagation algorithm and least squares method were applied for the training of ANFIS. The validation data was also applied to evaluate the performance of these models. Simulation results revealed that the testing results from these models were in good agreement with the experimental data.

关键词： flotation tailings leaching copper environments adaptive neural fuzzy inference system

Fischer–Tropsch synthesis using Co and Co-Ru bifunctional nanocatalyst supported on carbon nanotube prepared via chemical reduction method

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Journal of Energy Chemistry 2019年第1期28卷 9-22页

作者： Jafar Shariati Ali Haghtalab Amir Mosayebi department of chemical engineering Tarbiat Modares University department of chemical engineering Tafresh University

We used a chemical reduction method to synthesize the catalysts of cobalt(Co) and cobalt-ruthenium(Co-Ru) bifunctional supported on carbon nanotubes(CNTs) for Fischer–Tropsch synthesis(FTS) in a fixedbed reactor. These Co-Ru/CNTs catalysts were synthesized with various weight proportions of Ru/Co(0.1 to 0.4 wt%) with keeping a fixed amount of cobalt(10 wt%). Moreover, for comparison purpose, CNTs supported Co-and Co(Ru)-based catalysts at same loading as the above catalysts were prepared through impregnation method. We characterize the present catalysts through the various techniques such as Energy–dispersive X-ray(EDX), Transmission Electron Microscopy(TEM), Brunauer–Emmett–Teller(BET),Hydrogen-Temperature-Programmed Reduction(H_2-TPR), Hydrogen-Temperature-Programmed Desorption(H_2-TPD) and O_2 titration. Thus using the chemical reduction method, a narrow particle size distribution was obtained so that the small cobalt particles were confined inside the CNTs. The Co-based catalyst prepared by impregnation was compared with the Co-Ru catalysts at the same loading. The results demonstrated that the use of chemical reduction method led to decrease the average Co oxide cluster size to8.7 nm so that the reduction enhanced about 24% and stabilized an earlier time at the stream. Among the prepared catalysts, the results indicated that the Co-Ru/CNTs catalysts demonstrated high catalytic activity with the highest long-chain hydrocarbons(C_(5+)), selectivity up to 74.76%, which was higher than those we obtained by the Co-Ru/γ-Al_2O_3(61._20%), Co/CNTs(43.68%) and Co/γ-Al_2O_3(37.69%). At the same time, comparing with those catalyst synthesized by impregnation, the use of chemical reduction led to enhancement of the C_(5+) selectivity from 59.30% to 68.83% and increment in FTS rate about 11% for the Co-Ru/CNTs catalyst.

关键词： Cobalt-ruthenium Carbon nanotubes Fischer-Tropsch synthesis Catalyst nanoparticles chemical reduction method

SIZE DISTRIBUTION OF DROPLETS ABOVE A ROTATING STREAM TRAY AND MODEL OF DROPLET MOTION THEREIN

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Chinese Journal of chemical engineering 1997年第2期5卷 35-42页

作者：陈建孟谭天恩 department of chemical engineering Zhejiang University of Technology department of chemical engineering Zhejiang University

Droplet size distributions have been investigated with a two-probe system above a rotatingstream tray of 300 mm *** measured distributions are found to follow the upper limitedlognormal distribution with three parameters dependent primarily on gas hole F-factor.A probabilitymethod is used to describe the initial state of the droplet population above the tray,and a model fordroplet motion is *** results computed with model agree well with experimental data.

关键词： rotating stream tray droplet size distribution model for droplet motion

Remediation of sulfidic wastewater by catalytic oxidation with hydrogen peroxide

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Journal of Environmental Sciences 2009年第12期21卷 1735-1740页

作者： Naveed Ahmad Saikat Maitra Binay Kanti Dutta Farooq Ahmad department of chemical engineering Universiti Teknologi PETRONAS department of chemical engineering The Petroleum Institute

Oxidation of sulfide in aqueous solution by hydrogen peroxide was investigated in the presence of hydrated ferric oxide catalyst. The ferric oxide catalyst was synthesized by sol gel technique from ferric chloride and ammonia. The synthesized catalyst was characterized by Fourier transform infrared spectroscopy, X-Ray diffraction analysis, scanning electrom microscope and energy dispersive X-ray analysis. The catalyst was quite effective in oxidizing the sulfide by hydrogen peroxide. The effects of sulfide concentration, catalyst loading, H2O2 dosing and temperature on the kinetics of sulfide oxidation were investigated. Kinetic equations and activation energies for the catalytic oxidation reaction were calculated based on the experimental results.

关键词： catalytic oxidation wastewater kinetic equation hydrogen peroxide sodium sulfide remediation

Simultaneous production and utilization of methanol for methyl formate synthesis in a looped heat exchanger reactor configuration

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Journal of Natural Gas Chemistry 2012年第6期21卷 661-672页

作者： A.Goosheneshin R.Maleki D.Iranshahi M.R.Rahimpour A.Jahanmiri department of chemical engineering Lamerd Branch Islamic Azad University chemical engineering department School of Chemical and Petroleum Engineering Shiraz University

In this investigation, a novel thermally coupled reactor （TCR） containing methyl formate （MF） production in the endothermic side and methanol synthesis in the exothermic side has been investigated. The interesting feature of this TCR is that productive methanol in the exothermic side could be recycled and used as feed of endothermic side for MF synthesis. Other important advantages of the proposed system are high production rates of hydrogen and MF. The configuration consists of two thermally coupled concentric tubular reactors. In these coupled reactors, autothermal system is obtained within the reactor. A steady-state heterogeneous model is used for simulation of the coupled reactor. The proposed model has been utilized to compare the performance of TCR with the conventional methanol reactor （CMR）. Noticeable enhancement can be obtained in the performance of the reactors. The influence of operational parameters is studied on reactor performance. The results show that coupling of these reactions could be feasible and beneficial. Experimental proof-of-concept is required to validate the operation of the novel reactor.

关键词： methyl formate methanol synthesis looped heat exchanger reactor configuration steady-state heterogeneous model

Copper Catalyzed Iodosulfenylation of Styrenes by Dual C--H Oxidative Functionalization

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Chinese Journal of Chemistry 2017年第3期35卷 307-310页

作者： Yurong Liu Bolun Hu Xingguo Zhang College of chemisty and Materials engineering Wenzhou University Wenzhou Zhejiang 325027 China

A new method for the synthesis of β-iodoalkenyl sulfides via copper catalyzed difunctionalization of styrenes is described. The method allows the formation of two chemical bonds, a C—I bond and a C—S bond, in a single reaction. Using alkenes in place of alkynes to synthesize β-iodoalkenyl sulfides is a significant advantage of this methodology for both synthetic and medicinal chemistry.

关键词： β-iodoalkenyl sulfides iodosulfenylation iodine disulfides styrenes