Editors Ryuichi Egashira (Tokyo Institute of Technology) Jun Fukai (Kyushu University) Choji Fukuhara (Shizuoka University) Toshitaka Funazukuri (Chuo University) Takayuki Hirai (Osaka University) Jun-ichi Horiuchi (Kitami Institute of Technology) Eiji Iritani (Nagoya University) Yoshinori Itaya (Gifu University) Noriho Kamiya (Kyushu University) In-Beum Lee (Pohang University of Science and Technology (POSTEC)) Kouji Maeda (University of Hyogo) Hideyuki Matsumoto (Tokyo Institute of Technology) Nobuyoshi Nakagawa (Gunma University) Masaru Noda (Fukuoka University) Hiroyasu Ogino (Osaka Prefecture University) Mitsuhiro Ohta (The University of Tokushima) Eika W. Qian (Tokyo University of Agriculture and Technology) Yuji Sakai (Kogakuin University) Noriaki Sano (Kyoto University) Naomi Shibasaki-Kitakawa (Tohoku University) Ken-Ichiro Sotowa (The University of Tokushima) Hiroshi Suzuki (Kobe University) Nobuhide Takahashi (Shinshu University) Shigeki Takishima (Hiroshima University) Yoshifumi Tsuge (Kyushu University) Tomoya Tsuji (Nihon University) Da-Ming Wang (National Taiwan University) Takuji Yamamoto (University of Hyogo) Yoshiyuki Yamashita (Tokyo University of Agriculture and Technology) Miki Yoshimune (National Institute of Advanced Industrial Science and Technology (AIST))
Editorial office: The Society of Chemical Engineers, Japan Kyoritsu Building, 4-6-19, Kohinata, Bunkyo-ku Tokyo 112-0006, Japan firstname.lastname@example.org
AIMS AND SCOPE:
Journal of Chemical Engineering of Japan, an official publication of the Society of Chemical Engineers, Japan, is dedicated to providing timely original research results in the broad field of chemical engineering ranging from fundamental principles to practical applications. Subject areas of this journal are listed below. Research works presented in the journal are considered to have significant and lasting value in chemical engineering.
Physical Properties and Physical Chemistry Transport Phenomena and Fluid Engineering Particle Engineering Separation Engineering Thermal Engineering Chemical Reaction Engineering Process Systems Engineering and Safety Biochemical Food and Medical Engineering Micro and Nano Systems Materials Engineering and Interfacial Phenomena Energy Environment Engineering Education
The energy consumption of a sludge transport pipeline system has been analyzed and optimization calculation performed using the GA-DE (Genetic Algorithm–Differential Evolution) hybrid algorithm for the design parameters of the system. The factors influencing the total cost of the sludge transport pipeline system were studied first. In this analysis, sludge concentration and transport velocity were chosen as the two key parameters and optimized using a genetic algorithm and evolutionary algorithms. Next, a sludge transport project at one urban sewage treatment plant in Changchun City, Jilin Province was modeled with respect to cost and the optimization of two key parameters was carried out. The results showed that the optimal values of sludge concentration Cw, transport velocity v and pipeline diameter D were 2.32%, 1.10 m/s and 300 mm, respectively, under the conditions of sludge quantity Q=0.226–0.045 m3/s (sludge concentration Cw=0.8–4.0%) and transport length L=4.5×103 m. The total annualized cost W was 528,300 RMB under this scheme. The test example confirms that the GA-DE hybrid algorithm is feasible and highly efficient for the parameter design optimization of a sludge transport pipeline system. Finally, the bias curve of the specific total annualized cost was used for the selection of the optimization schemes for each of the sludge concentration partitions.
Urea prills are produced in a prilling tower where a cooling-solidification process takes place. The ambient air is used as the cooling air stream for this process. In this study, the cooling-solidification process was numerically investigated in the particle size range of commercial product. The simulations predicted that the temperature of smaller particles fully solidified became nearly identical with that of cooling air over the entire body at the bottom of tower. It was found, on the other hand, that the temperature of larger particles remained high over a large portion of its core part. SEM observation of the particle cross-section favorably validated the numerical predictions.
A modified Discrete Element Method incorporating force models for calculating van der Waals forces, electrostatic repulsion forces, hydrodynamic lubrication forces, magnetic dipole–dipole interactions and Brownian effects was applied towards the study of shear aggregation of non-magnetic and magnetic colloidal nanoparticles. The effects of initial solid volume fraction of nanoparticles, initial morphology of aggregates formed via self-assembly in the absence of fluid flow and shear rate when simple shear flow was applied were investigated. The time evolution of the various forces present within these systems was analyzed to provide a more fundamental and mechanistic understanding of the various phenomena observed during shear aggregation of the non-magnetic and magnetic colloidal nanoparticles.
Charging characteristics of carbon nanofibers (CNFs) with a 241-Am charge neutralizer were investigated using diameter- and length-controlled CNF particles, which were generated by a floating catalyst CVD method. The neutral fraction and charge distribution of CNF measured by aerosol techniques suggested that the fraction of neutral particles is much lower than that predicted by the conventional charging theory for spherical particles and that there exist a large number of multiply charged particles in charge equilibrium. Furthermore, it was found that the charge equivalent diameter that is twice the one proposed in a previous work gives a good prediction for the charge distribution of CNF with a diameter smaller than 20 nm and aspect ratio between 5 and 40.
The crosslinked and highly porous chitosan microspheres PHAC that introduce phosphinic acid as a ligand were synthesized to apply to perfusion chromatography for the recovery of indium(III) and gallium(III). The formation of pores of PHAC was performed through dehydration caused by the difference of the water osmotic pressure for dehydration from the oil-in-water-in-oil (O/W/O) emulsion containing chitosan in the water phase and the W/O emulsion containing 15 wt% sodium chloride in the aqueous phase. Introduction of phosphinic acid moiety was carried out after crosslinking with glutaric aldehyde by using phosphinic acid and paraformaldehyde according to the Mannich reaction. The microspheres were an average diameter of 100 µm and average pore size of 3.75 nm. The adsorption of metal ions on PHAC was examined from a 1 M aqueous ammonium nitrate solution by a batchwise method. PHAC exhibited high selectivity for In(III) and Ga(III) in the aqueous ammonium nitrate solution. PHAC selectively adsorbed In(III) and Ga(III) over other metals such as copper(II), zinc(II), cobalt(II), nickel(II) and cadmium(II) below pH 2, suggesting that PHAC can perform the selective adsorption of In(III) and Ga(III) only by adjusting pH in the aqueous solution.
The synergistic extraction of rare-earth metals by a β-diketone and an organophosphine oxide is described. A combination of 2-thenoyltrifluoroacetone (HTTA) and tri-n-octyl phosphine oxide (TOPO) was found to be effective in synergistically extracting rare-earth metals into an ionic liquid (IL). The synergistic effect was strongly influenced by the diluent in which the extractants were dissolved. Extraction efficiencies for all the rare-earth metal ions were enhanced by synergy when a conventional organic solvent was used (n-dodecane). However, the synergistic effect in the IL preferentially improved the scandium extraction, leading to higher selectivity for Sc than for other rare-earth metals. Slope analysis was used to assess each extraction system, and the IL itself was found to be directly involved in the complex formation of the metal extraction system.
2-(Isopropylamino)ethanol-based solvent for carbon dioxide (CO2) capture from coal-fired flue gas was evaluated through pilot plant tests and process simulation. A 10 t-CO2/d-scale pilot plant was operated at various conditions of liquid-to-gas ratio and steam feed rates. Also, a process simulation was carried out to estimate CO2 recovery and the thermal energy requirement for the chemical absorption process. As a result, the minimum energy requirement of the solvent for CO2 capture was 3.0 GJ/t-CO2 at 90% CO2 recovery in the pilot plant operation. The process simulation also showed the potential of the solvent which could reduce the energy requirement by 30% compared with a monoethanolamine (MEA) 30 wt% aqueous solution.
The extraction behavior of platinum(II), platinum(IV) and palladium(II) with an ionic liquid, 1-octyl-3-methylimidazolium hexafluorophosphate ([Omim][PF6]), and a quaternary ammonium salt, distearyldimethylammonium chloride (DSDMAC), as extractants has been investigated in a liquid–liquid extraction system. In the present experimental conditions, platinum was extracted selectively over palladium by both extractants. It was found that DSDMAC possessed a higher extraction ability for the metals than that of [Omim][PF6]; on the other hand, more effective separation of platinum and palladium was achieved using [Omim][PF6] than using DSDMAC. The composition of the complex between their metals and extractants was elucidated by slope analysis and Job’s method. The metals exist as chloro anion complexes in a hydrochloric acid solution, which reacted with extractant molecules in chloroform and were extracted into the organic solutions. Furthermore, platinum could be separated from palladium in an acidic chloride medium using the ionic liquid as an extractant.
A series of manganese–ferrum oxides (Mn–Fe) catalysts were prepared by organic solvent method and tested for low temperature catalytic oxidation of nitric oxide (NO). The effects of doping of PEG1000 and Fe were studied. These catalysts were characterized by X-ray diffraction (XRD) Brunauer-Emmett-teller measurements (BET) and scanning electron microscope (SEM) methods. Screening and optimization of catalysts formulation and preparation conditions could be achieved by the orthogonal tests, and the influencing law was analyzed. In this method, effects of (Mn7++Mn2+) : Fe3+, Mn7+ : Mn2+, PEG1000/(Mn7++Mn2++Fe3+), agitation temperature and calcination temperature were investigated. The experimental results showed that the best catalyst yielded 91% NO conversion at 100°C (volume fraction of NO was 500 ppm, O2 was 3%, space velocity was 45,000 h−1), and the most active catalyst was obtained with a molar PEG/(Mn7++Mn2++Fe3+) ratio of 1.0%. Orthogonal tests showed that the most obvious effect factor on NO conversion was calcination temperature. The effect order was calcination temperature>PEG1000/(Mn7++Mn2++Fe3+)>Mn7+ : Mn2+>(Mn7++Mn2+) : Fe3+>agitation temperature.
This study examines the optimal operation of the dual mixed refrigerant (DMR) process by steady-state optimality analysis. The purpose of this analysis is to discover the optimizing variable that can maintain the DMR process in the optimal compressor duty. First, a rigorous dynamic simulation of the DMR process was built in the Aspen Hysys interface. Second, numerous step tests on the refrigerant flow rate were conducted and the resulting total compressor duty was recorded. The steady-state operational map that correlates the refrigerant flow rate and total compressor duty was drawn to locate the optimal operation region of the DMR process. The map also contains information on the state variables in the DMR process that in particular combinations, will allow the process to be operated at the optimal compressor duty. The comprehensive information on the map makes it an excellent tool for selecting the proper optimizing variable for the DMR process. The resulting steady-state optimality map suggests that, when the flow rate ratio of the two refrigerants (WMR/CMR ratio) is kept constant, the operational of DMR process will remain within optimal region. This suggests that the WMR/CMR ratio is the proper optimizing variable for the DMR process. From a control viewpoint, the control structure that includes the WMR/CMR ratio loop also showed excellent performance compared to the other possible structures in terms of maintaining the stability and fulfilling the control objectives of the DMR process.
The naphtha splitter process is a representative distillation processused in the refinery industry. To improve the fractionation of the naphtha boiling range derived from hydro-treatment, naphtha feedstock is sequentially separated into light naphtha, heavy naphtha, and light kerosene. Conventional naphtha splitting columns can be retrofitted to an advanced configuration requiring less energy consumption with consequently less CO2 emission. A systematic design for retrofitting naphtha splitting columns for the thermally coupled distillation sequence (TCDS) that addresses the bottleneck phenomenon by integration of existing shells was developed in this study. The results showed that the operating cost could be reduced drastically by novel combination of the TCDS and a side reboiler with minimal process modification.
To obtain Sn and Cu–Sn alloy films, Sn and Cu–Sn precursors, respectively, were first prepared by a wet chemical method using metal organics as the starting materials. The change in the chemical form during a heat treatment and the effect of atmosphere on the formation of the films were investigated. A dense metallic Sn film was successfully obtained from the Sn precursor solution, which was prepared by mixing Sn oxalate, tetraethylene glycol, and 1,2-diaminocyclohexane with a molar ratio of 1 : 3 : 3, and by pyrolysis at 500°C in a nitrogen stream containing 3 vol% hydrogen. During the formation of the Sn precursor, the viscosity of the solution was found to increase with the formation of an oxamide, which was in turn created by the reaction between Sn oxalate and 1,2-diaminocyclohexane in a polymerization process. Tetraethylene glycol did not participate in the reaction because it functions as a dispersant. A Cu–Sn alloy film was also successfully obtained by the pyrolysis of the Cu–Sn precursor prepared by the mixture of Cu and Sn precursors at 500°C in a nitrogen stream containing 3 vol% hydrogen. The composition of the Cu–Sn alloy film can be controlled by changing the mixing ratio of the Cu and Sn precursors.
Brominating butyl rubber (IIR) in the presence of oxidant, NaClO, and electrophilic solvent, CH2Cl2, is a promising preparation technique of bromobutyl rubber (BIIR), while there lacks comprehensive reports on this technique in the literature. In view of this, the present study paper systematically investigates the bromination conditions of IIR in a stirred tank reactor. The effects of process parameters on product quality in terms of the Br content (W) and the unsaturation degree (Ω) were obtained. Acceleration of the bromination and increase in W were realized by increasing the volume fraction of CH2Cl2(φCH2Cl2) in the solvent. With the optimum φCH2Cl2, 30%, the bromination reaction could be accomplished in 5 min. With the increase of NaClO dosage, W increased, which meant an increase in Br2 utilization. With the increase of Br2 dosage, W also increased, while the Br2 utilization decreased. Regarding W, a slight effect of IIR concentration, a significant effect of mixing intensity and no effect of temperature were found, respectively. Besides φCH2Cl2, the above bromination conditions exerted inverse and slight effects on Ω, comparing with their effects on W. These results have indicated methods to regulate the product quality of BIIR, and can be concluded as the development of a new preparation technique of BIIR.
We immobilized 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonate) through a spacer to polymer grafted onto carbon black to fabricate a three-dimensional biocathode with high surface area that reduces oxygen in the presence of laccase. Cyclic voltammetry using a rotating disk electrode shows that an oxygen reduction reaction (ORR) current density greater than 1 mA cm−2 at 200 rpm was obtained using the grafted redox polymer in the presence of 1.0 mg mL−1 of laccase in solution. The onset potential of the ORR current suggests that the electron transfer from carbon through grafted redox polymer to laccase was more effective than that through cast linear redox polymer.