查看更多>>摘要：? 2022 The Korean Society of Industrial and Engineering ChemistryThis study uses a simple galvanic displacement-acid etching method for synthesizing PtNi nanoparticles with different morphologies and surface properties. Core/shell structured Ni/PtNi nanoparticles were prepared from nickel nanoparticles subjected to a galvanic displacement reaction with Pt ions. By controlling the dealloying conditions, hollow PtNi/Pt core/shell (H-PtNi/Pt) and Pt-only (H-Pt) nanoparticles could be formed. The H-PtNi/Pt catalyst showed the highest oxygen reduction reaction (ORR) mass and specific activities (0.8 A mg?1Pt and 1520 μA cm?2Pt at 0.9 VRHE), which were 3.33- and 5.67-times higher than those of commercial Pt/C. It revealed that forming a PtNi/Pt core/shell structure with a hollow morphology plays an important role for enhancing ORR activity. The H-PtNi/Pt catalyst also showed a very low degradation in specific activity of less than 1% after extensive potential cycling (10,000 cycles) due to the stable platinum outer layer covering the hollow PtNi alloy structure.
Jimenez-Hornero J.E.Santos Duenas I.M.Garcia-Garcia I.
16页
查看更多>>摘要：? 2022 The Korean Society of Industrial and Engineering ChemistryFirst-principles models of any process usually describe its complex underlying mechanisms using differential and algebraic equations including several unknown parameters, whose values must be normally estimated from experimental data. In this context, assessment of the influence of each parameter on model outputs, also known as sensitivity analysis, is an invaluable tool to, for example, simplify the structure of such model. In this work, variance-based Global Sensitivity Analysis (GSA) using Sobol’ main and total effects was carried out on a previously proposed acetification process first-principles model. Three parameters (KSE, KIA and KSO) showed less influence than the remaining nine considering their stated value ranges; KSE presented no influence in all the analysed experimental conditions, value variation of KIA exhibited a slightly greater effect on experiments with higher mean acetic acid concentrations and KSO showed the strongest impact by varying its value in all the experiments. According to these results, the model was simplified and its simulation compared with the initially proposed model and the experimental data. The analysis performed, by way of example, can be of crucial importance for any other process.
查看更多>>摘要：? 2022 The Korean Society of Industrial and Engineering ChemistryThis research focuses on controlling the morphology and crystalline phase of hollow Al2O3 spheres as a supporting material of Ni-based catalysts for the first time, which is then applied as a catalyst of high-temperature steam methane reforming (SMR) process. For this purpose, the effects of hydrothermal time, the concentration of alumina salt, and calcination temperature on the structure of support are investigated and adjusted and then loaded with 15–25 wt.% Ni contents. The morphology of synthesized hollow alumina samples and 20Ni/H-Al2O3 catalyst before and after reaction are characterized using XRD, FESEM, TEM, H2-TPR, CO2-TPD, EDX, FTIR, N2 adsorption/desorption, and mapping techniques. The hydrothermal time of 72 h, calcination temperature of 800 °C, and alumina salt concentration of 1.00 M resulted in the spherical morphology of hollow Al2O3 with 236.26 m2/gr surface area and high crystallinity. Among different Ni loadings, 20Ni/H-Al2O3 had the highest CH4 conversion of 87.75% and H2 yield of 92.09% at 700 °C. This catalyst also depicted stable performance during 12 h SMR reaction at 700 °C with low carbon deposited contents.
查看更多>>摘要：? 2022 The Korean Society of Industrial and Engineering ChemistryDeep eutectic solvents (DESs) prepared by mixing hydrogen bond donors (HBDs) and acceptors (HBAs) are attracting attention to use absorbents for carbon capture, storage, and utilization (CCUS) technology, but their applications in large-scale industries are limited by the scarce research in the field. When DES was used as CO2 absorbent, the use of appropriate HBAs and HBDs is critical for application. In this study, choline chloride (ChCl, as the HBA) was mixed with five different HBDs and diluted to 20 wt% water (W) for improvement of mass transfer, and their CO2 absorption capacities and physicochemical properties were analyzed. Urea (U), ethylene glycol, glycerol, and malic and levulinic acids were used as HBDs due to their various functional groups. ChCl:U:W can be a potential alternative to conventional alkanolamine absorbents for use in CCUS among the studied DESs, as its absorption capacity was superior to those of the other DESs. Increase of surface tension and decrease of density and viscosity were observed by addition of water on all of DESs. Additionally, absorption rate increased via water addition. This study can contribute to the future development of a more efficient CCUS technology using solvent alternatives that are more suitable for future environmental challenges.
查看更多>>摘要：? 2022 The Korean Society of Industrial and Engineering ChemistryA series of bimetallic UTSA-16 (Zn, X; X = Mg, Mn, and Cu) metal organic frameworks (MOFs) with different metal ratios was synthesized using a microwave irradiation method. Synthesis at an optimal Zn-to-metal ratio of 7:2 achieved a 9–18% increase in the CO2 adsorption capacity and an enhanced adsorption selectivity of CO2 over N2 compared to those of the parent UTSA-16 (Zn). Bimetallic UTSA-16 powders, with ratios of 7:2, were pelletized for a stability study that exposed the pellets to acid gases (NO2 and SO2) in a humid air condition; additionally, they underwent adsorption–desorption cyclic experiments. The results showed that the CO2 capture performance was consistent after exposure to NO2 gas in humid air and adsorption–desorption cycling with temperature swing. The morphological properties of the bimetallic MOFs were characterized using scanning electron microscopy, Brunauer ? Emmett ? Teller analysis, Fourier transform infrared spectroscopy, and X-ray diffraction. The characterization data showed that the bimetallic UTSA-16 (Zn, X) MOFs exhibited good crystallinity and morphology, similar to the original UTSA-16 (Zn) MOF.
查看更多>>摘要：? 2022 The Korean Society of Industrial and Engineering ChemistryImportance in the precise determination of Furazolidone (FZD) on biological, food, and water samples were established for regulating health and nutrition, diagnosis/treatment, pharmacological research, and food/drug quality monitoring. Thus, the sensitive and accurate determination of FZD is necessary. Here, we construct facile and low-cost Metal Titanate (MTiOx, M = Mn, Fe, Cu) as an electrode modifier via a different one-step synthesis method. By the virtue of unique properties, MnTiO3 has been successfully employed in the electrochemical evaluation of FZD such as high active surface area (0.1252 cm2) and high electron transfer kinetics with low charge transfer resistance (Rct = 374.65 Ω) with good electro-catalytic kinetic parameters. In this regard, MnTiO3 is employed in the electrochemical evaluation of FZD through cyclic voltammetry (CV) and Differential Pulse Voltammetry (DPV) techniques. The proposed MnTiO3/GCE sensor shows exquisite electrochemical characteristics including a wide linear range (0.05 to 1101.6 μM), nanomolar detection limit (4.05 nM), and encouraging sensitivity (68.77 μA μM?1 cm?2). Moreover, it also exemplifies exquisite selectivity, repeatability, reproducibility, and storage stability therefore; MnTiO3 is employed in the practical feasibility analysis in various real samples, which shows excellent recovery results.
查看更多>>摘要：? 2022 The Korean Society of Industrial and Engineering ChemistryLow-temperature carbonization–sulfonation two-step process or one-step sulfonation process was employed to draft sodium lignosulfonate (SLS), the primary biological macromolecule ingredient of papermaking black liquor, into lignin-based sulfonated carbon. The two-step lignin-based sulfonated carbon named SLC400,1S was found to be an efficient catalyst for clean Benzyl-alcohol (BA) route Friedel-Crafts (F-C) benzylation of benzene ring compounds. FT-IR, XRD, Raman spectra, XPS, SEM with EDX-mapping, TGA-DSC, acid-base titration, and n-butylamine–acetonitrile titration characterizations demonstrated that the specific two-step process could introduce porous properties and a large number of surface sulfonic, hydroxyl, and carboxyl active groups into the structure of the prepared material, which was found to account for the good catalytic performance for benzylation. Similar to that of hierarchical mesoporous ZSM-5 under optimal conditions, the apparent activation energy for benzylation of paraxylene (PX) with BA over SLC400,1S was estimated to be 119 kJ·mol?1. The common by-product of BA route benzylation, dibenzyl ether (DBE), was almost inhibited because of the extraordinary activity of SLC400,1S and the optimized reaction conditions. A 12-run recycling test demonstrated easy recovery and steady reusability of the above lignin-based sulfonated carbon catalyst.
查看更多>>摘要：? 2022 The Korean Society of Industrial and Engineering ChemistryTin dioxide (SnO2) films deposited on transparent conductive substrates have been considered as promising candidates for photoelectrochemical and photovoltaic applications due to their promising properties such as high electron mobility, stability, and favorable band edges positions. Therefore, a simple electrochemical approach based on the cathodic deposition of SnO2 on a conductive glass substrate was proposed. SnO2 layers were obtained by electrodeposition from SnCl2 solution containing HNO3 at various potentials (from ?0.6 V to ?1.0 V vs. SCE) for various durations (from 5 min to 180 min). The obtained materials were then annealed in air at 400 °C and characterized. The co-deposition of the metallic phase at the most negative potential was confirmed. However, it was successfully converted to the oxide phase by thermal treatment. The photoelectrochemical activity of the materials during illumination with monochromatic light from the range between 250 and 500 nm was studied. The higher photocurrents were generated by annealed layers, and the most promising photoelectrochemical properties were observed for the sample deposited at ?0.8 V vs. SCE for 180 min. It is expected that such a simple electrochemical approach can be an effective strategy for the fabrication of highly efficient photoanodes for photoelectrochemical and photovoltaic applications.
查看更多>>摘要：? 2022 The Korean Society of Industrial and Engineering ChemistryWe describe the phase-transfer biocatalytic process for methane-to-methanol conversion based on the spontaneous phase-separable membrane micro-CSTR (μCSTR). The developed system has several critical benefits for operating the conversion reaction, including (a) preventing the whole-cell biocatalyst loss while operating the reactor continuously, (b) introducing a powerful mixing effect to significantly improve the mass transfer efficacy of methane to the biocatalyst, (c) facilitating the product separation process by employing the spontaneous phase separation system, and (d) providing an excellent platform for more complex, high-value-added conversion reactions.
查看更多>>摘要：? 2022 The Korean Society of Industrial and Engineering ChemistryThe petrol-based random copolymer, e.g., aromatic-hydrocarbon resin, is widely used in industrial production, but the research about its gas–liquid two flow is far from being solved. Herein, the formation, motion, and deformation of a single bubble in six different concentrations of random copolymer solutions were systemically investigated using high-speed photography (1000 fps), combined with digital image processing technology. The departure time of the bubble first decreases and then increases, and maximum of aspect ratio and specific surface area reduce as the proportion of solute increases. The bubble departure time decreases and bubble size increases with viscous force increases in the case of same surface tension. Based on force balance analysis, added mass force is one of the prime reasons to affect bubble oscillation during the acceleration phase after bubble detachment, whereas the effect of added mass force decreases as solute increases or as the bubble reaches stability zone. Also, velocity, drag coefficient and aspect ratio of bubble were discussed in detail by dimensionless analysis. Furthermore, three new shape numerical models (based on We, Ta, and WeEo, respectively) were proposed, which allowed for satisfactory predictions, and new correlations represent well the experimental data in a wider range of Mo numbers from the mentioned literature (?11.6 ≤ logMo ≤ 0.63).
NSTL
Elsevier