Pub Date : 2024-11-15DOI: 10.1016/j.apt.2024.104722
Yunzhou Qian , Shane P. Usher , Peter J. Scales , Anthony D. Stickland , Alessio Alexiadis
This study introduces a three-dimensional (3D) Discrete Element Method (DEM) model designed to simulate particle consolidation under simultaneous compression and shear forces. The model is validated against experimental data for pure compression scenarios. Simulations involving simultaneous compression and shear are conducted to understand the impact of varying shear-to-compression ratios on particle consolidation. High shear-to-compression ratios lead to denser particle clusters, showing that shear promotes increased solid volume fractions. Additionally, the study explores the influence of different particle–particle interaction models, specifically the Derjaguin-Muller-Toporov (DMT) and Johnson-Kendall-Roberts (JKR) models. The results indicate that the DMT model generally leads to denser, more compact aggregates, whereas the JKR model tends to produce aggregates with a more elongated structure. Different agglomeration patterns were also found, which were classified as ‘shear-dominated’, ‘plateau’ and ‘compression-dominated’.
{"title":"Numerical simulation of particle consolidation under compression and shear based on the Discrete Element method","authors":"Yunzhou Qian , Shane P. Usher , Peter J. Scales , Anthony D. Stickland , Alessio Alexiadis","doi":"10.1016/j.apt.2024.104722","DOIUrl":"10.1016/j.apt.2024.104722","url":null,"abstract":"<div><div>This study introduces a three-dimensional (3D) Discrete Element Method (DEM) model designed to simulate particle consolidation under simultaneous compression and shear forces. The model is validated against experimental data for pure compression scenarios. Simulations involving simultaneous compression and shear are conducted to understand the impact of varying shear-to-compression ratios on particle consolidation. High shear-to-compression ratios lead to denser particle clusters, showing that shear promotes increased solid volume fractions. Additionally, the study explores the influence of different particle–particle interaction models, specifically the Derjaguin-Muller-Toporov (DMT) and Johnson-Kendall-Roberts (JKR) models. The results indicate that the DMT model generally leads to denser, more compact aggregates, whereas the JKR model tends to produce aggregates with a more elongated structure. Different agglomeration patterns were also found, which were classified as ‘shear-dominated’, ‘plateau’ and ‘compression-dominated’.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"35 12","pages":"Article 104722"},"PeriodicalIF":4.2,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-14DOI: 10.1016/j.apt.2024.104727
Masaru Kubo, Akito Kawamoto, Manabu Shimada
N-doped nanoporous carbon (NPC) was synthesized from ZIF-8 metal–organic framework via a one-step ultrasonic spray pyrolysis (USP) process and evaluated as a supercapacitor electrode material. The USP method involves ultrasonic nebulization of a ZIF-8 suspension, formation of agglomerates by preheating the droplets, and carbonizing the agglomerates at 1100 °C to yield USP-NPC. For comparison, conventional ZIF-8-derived NPC (c-NPC) and spray-dried ZIF-8 derived NPC (SD-NPC) were also prepared. USP-NPC consists of spherical dense submicron particles with a BET surface area of 1059 m2/g and high N content (6.4 at%). Electrochemical tests revealed that USP-NPC exhibited superior supercapacitance performance (249.7F/g at 0.5 A/g) and 10000-cycles durability compared to c-NPC and SD-NPC. The enhanced performance of USP-NPC is attributed to its spherical morphology, high surface area, and rich N-doping. This study demonstrates that the USP method is a promising approach for the facile synthesis of high-performance NPC electrode materials for supercapacitor applications.
{"title":"Preparation of N-doped nanoporous carbon from ZIF-8 metal-organic framework via ultrasonic spray pyrolysis","authors":"Masaru Kubo, Akito Kawamoto, Manabu Shimada","doi":"10.1016/j.apt.2024.104727","DOIUrl":"10.1016/j.apt.2024.104727","url":null,"abstract":"<div><div>N-doped nanoporous carbon (NPC) was synthesized from ZIF-8 metal–organic framework via a one-step ultrasonic spray pyrolysis (USP) process and evaluated as a supercapacitor electrode material. The USP method involves ultrasonic nebulization of a ZIF-8 suspension, formation of agglomerates by preheating the droplets, and carbonizing the agglomerates at 1100 °C to yield USP-NPC. For comparison, conventional ZIF-8-derived NPC (c-NPC) and spray-dried ZIF-8 derived NPC (SD-NPC) were also prepared. USP-NPC consists of spherical dense submicron particles with a BET surface area of 1059 m<sup>2</sup>/g and high N content (6.4 at%). Electrochemical tests revealed that USP-NPC exhibited superior supercapacitance performance (249.7F/g at 0.5 A/g) and 10000-cycles durability compared to c-NPC and SD-NPC. The enhanced performance of USP-NPC is attributed to its spherical morphology, high surface area, and rich N-doping. This study demonstrates that the USP method is a promising approach for the facile synthesis of high-performance NPC electrode materials for supercapacitor applications.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"35 12","pages":"Article 104727"},"PeriodicalIF":4.2,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656256","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-14DOI: 10.1016/j.apt.2024.104686
Li Xiang , Xiang Yang , Chen Xing , Li Jinze , Wang Tong , Xia Xietian
Hydrodynamics of droplet coating process are simulated using an airless rotary sprayer by means of CFD-discrete element method (DEM) with JKR contact model. The surface energy parameter used in the JKR model is calibrated by a virtual accumulation angle test. A reasonable wall-droplet surface energy is suggested according to accumulation angle distribution. The droplet translational and angular velocities are predicted at different rotation speeds of the rotary sprayer labeled I, II and III. For stationary rotary sprayer coating process, the droplet translational and angular velocities, normal and tangential forces and energy losses are proportional to rotation speeds. As the rotary sprayer moves forward, the droplet-wall collision normal and tangential forces and energy losses are large near the inlet region and trends constantly in the developed region. This work suggests that DEM could be a useful method to study the effect of rotation speeds on droplet-wall contact interactions in paint droplet coating process.
{"title":"Simulations of hydrodynamics of droplet coating process using airless rotary sprayers","authors":"Li Xiang , Xiang Yang , Chen Xing , Li Jinze , Wang Tong , Xia Xietian","doi":"10.1016/j.apt.2024.104686","DOIUrl":"10.1016/j.apt.2024.104686","url":null,"abstract":"<div><div>Hydrodynamics of droplet coating process are simulated using an airless rotary sprayer by means of CFD-discrete element method (DEM) with JKR contact model. The surface energy parameter used in the JKR model is calibrated by a virtual accumulation angle test. A reasonable wall-droplet surface energy is suggested according to accumulation angle distribution. The droplet translational and angular velocities are predicted at different rotation speeds of the rotary sprayer labeled I, II and III. For stationary rotary sprayer coating process, the droplet translational and angular velocities, normal and tangential forces and energy losses are proportional to rotation speeds. As the rotary sprayer moves forward, the droplet-wall collision normal and tangential forces and energy losses are large near the inlet region and trends constantly in the developed region. This work suggests that DEM could be a useful method to study the effect of rotation speeds on droplet-wall contact interactions in paint droplet coating process.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"35 12","pages":"Article 104686"},"PeriodicalIF":4.2,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-14DOI: 10.1016/j.apt.2024.104723
So Segawa , Prima Asmara Sejati , Yosephus Ardean Kurnianto Prayitno , Noritaka Saito , Masahiro Takei
<div><div>Spatiotemporal distribution visualization of solid volume fraction during LiCl-KCl molten salt solidification has been visualized by thermal-compensated electrical resistance tomography (<em>tc</em>ERT). The <em>tc</em>ERT consists of three steps which are 1) conductivity interpolation step, 2) conventional conductivity reconstruction step, and 3) phase-fraction conversion step. In the first step, the liquid electrical conductivity <span><math><mrow><msup><mrow><mspace></mspace></mrow><mi>L</mi></msup><mi>σ</mi><mrow><mo>(</mo><mi>x</mi><mo>,</mo><mi>T</mi><mo>)</mo></mrow></mrow></math></span> under mole fraction <span><math><mrow><mi>x</mi></mrow></math></span> of KCl and measured temperature <span><math><mrow><mi>T</mi></mrow></math></span> is defined by conductivity interpolation diagram (CID). In the second step, the electrical conductivity during solidification is defined by the conventional heat-resistant ERT as the reconstructed solid and liquid conductivity <span><math><mrow><msup><mrow><mspace></mspace></mrow><mrow><mi>S</mi><mo>+</mo><mi>L</mi></mrow></msup><mrow><mi>σ</mi><mo>(</mo><mi>r</mi><mo>,</mo><mi>θ</mi><mo>,</mo><mi>T</mi><mrow><mo>(</mo><mi>t</mi><mo>)</mo></mrow></mrow></mrow></math></span>. From both steps, the solidification volume fraction <span><math><mrow><mi>φ</mi><mo>(</mo><mi>r</mi><mo>,</mo><mi>θ</mi><mo>,</mo><mi>T</mi><mo>(</mo><mi>t</mi><mo>)</mo><mo>)</mo></mrow></math></span> is calculated by the solid–liquid conductivity model (SLCM) which converts <span><math><mrow><msup><mrow><mspace></mspace></mrow><mrow><mi>S</mi><mo>+</mo><mi>L</mi></mrow></msup><mi>σ</mi><mrow><mo>(</mo><mi>r</mi><mo>,</mo><mi>θ</mi><mo>,</mo><mi>T</mi><mrow><mo>(</mo><mi>t</mi><mo>)</mo></mrow><mo>)</mo></mrow></mrow></math></span> into <span><math><mrow><mi>φ</mi><mo>(</mo><mi>r</mi><mo>,</mo><mi>θ</mi><mo>,</mo><mi>T</mi><mo>(</mo><mi>t</mi><mo>)</mo><mo>)</mo></mrow></math></span> by referring to <span><math><mrow><msup><mrow><mspace></mspace></mrow><mi>L</mi></msup><mi>σ</mi><mrow><mo>(</mo><mi>x</mi><mo>,</mo><mi>T</mi><mo>)</mo></mrow></mrow></math></span>. The <em>tc</em>ERT was applied to a composition of 85 mol % LiCl–15 mol % KCl in a crucible with platinum-wire electrodes under the initial temperature <span><math><mrow><msup><mrow><mspace></mspace></mrow><mn>0</mn></msup><mi>T</mi><mo>=</mo></mrow></math></span> 700 °C and at cooling rate <span><math><mrow><mi>γ</mi><mo>=</mo></mrow></math></span> 4.44 °C/min. As the results, inhomogeneous and unsteady <span><math><mrow><mi>φ</mi><mo>(</mo><mi>r</mi><mo>,</mo><mi>θ</mi><mo>,</mo><mi>T</mi><mo>(</mo><mi>t</mi><mo>)</mo><mo>)</mo></mrow></math></span> distributions were precisely visualized with a maximum relative error <span><math><mrow><mi>ζ</mi><mo>=</mo></mrow></math></span> 0.763 of space-mean <span><math><mrow><mo>〈</mo><mi>φ</mi><mo>〉</mo><mo>(</mo><mi>T</mi><mo>(</mo><mi>t</mi><mo>)</mo><mo>)</mo></mrow></math></span>, where the inhomogeneity refers to the sp
{"title":"Spatiotemporal distribution visualization of solid volume fraction during LiCl-KCl molten salt solidification by thermal-compensated electrical resistance tomography (tcERT)","authors":"So Segawa , Prima Asmara Sejati , Yosephus Ardean Kurnianto Prayitno , Noritaka Saito , Masahiro Takei","doi":"10.1016/j.apt.2024.104723","DOIUrl":"10.1016/j.apt.2024.104723","url":null,"abstract":"<div><div>Spatiotemporal distribution visualization of solid volume fraction during LiCl-KCl molten salt solidification has been visualized by thermal-compensated electrical resistance tomography (<em>tc</em>ERT). The <em>tc</em>ERT consists of three steps which are 1) conductivity interpolation step, 2) conventional conductivity reconstruction step, and 3) phase-fraction conversion step. In the first step, the liquid electrical conductivity <span><math><mrow><msup><mrow><mspace></mspace></mrow><mi>L</mi></msup><mi>σ</mi><mrow><mo>(</mo><mi>x</mi><mo>,</mo><mi>T</mi><mo>)</mo></mrow></mrow></math></span> under mole fraction <span><math><mrow><mi>x</mi></mrow></math></span> of KCl and measured temperature <span><math><mrow><mi>T</mi></mrow></math></span> is defined by conductivity interpolation diagram (CID). In the second step, the electrical conductivity during solidification is defined by the conventional heat-resistant ERT as the reconstructed solid and liquid conductivity <span><math><mrow><msup><mrow><mspace></mspace></mrow><mrow><mi>S</mi><mo>+</mo><mi>L</mi></mrow></msup><mrow><mi>σ</mi><mo>(</mo><mi>r</mi><mo>,</mo><mi>θ</mi><mo>,</mo><mi>T</mi><mrow><mo>(</mo><mi>t</mi><mo>)</mo></mrow></mrow></mrow></math></span>. From both steps, the solidification volume fraction <span><math><mrow><mi>φ</mi><mo>(</mo><mi>r</mi><mo>,</mo><mi>θ</mi><mo>,</mo><mi>T</mi><mo>(</mo><mi>t</mi><mo>)</mo><mo>)</mo></mrow></math></span> is calculated by the solid–liquid conductivity model (SLCM) which converts <span><math><mrow><msup><mrow><mspace></mspace></mrow><mrow><mi>S</mi><mo>+</mo><mi>L</mi></mrow></msup><mi>σ</mi><mrow><mo>(</mo><mi>r</mi><mo>,</mo><mi>θ</mi><mo>,</mo><mi>T</mi><mrow><mo>(</mo><mi>t</mi><mo>)</mo></mrow><mo>)</mo></mrow></mrow></math></span> into <span><math><mrow><mi>φ</mi><mo>(</mo><mi>r</mi><mo>,</mo><mi>θ</mi><mo>,</mo><mi>T</mi><mo>(</mo><mi>t</mi><mo>)</mo><mo>)</mo></mrow></math></span> by referring to <span><math><mrow><msup><mrow><mspace></mspace></mrow><mi>L</mi></msup><mi>σ</mi><mrow><mo>(</mo><mi>x</mi><mo>,</mo><mi>T</mi><mo>)</mo></mrow></mrow></math></span>. The <em>tc</em>ERT was applied to a composition of 85 mol % LiCl–15 mol % KCl in a crucible with platinum-wire electrodes under the initial temperature <span><math><mrow><msup><mrow><mspace></mspace></mrow><mn>0</mn></msup><mi>T</mi><mo>=</mo></mrow></math></span> 700 °C and at cooling rate <span><math><mrow><mi>γ</mi><mo>=</mo></mrow></math></span> 4.44 °C/min. As the results, inhomogeneous and unsteady <span><math><mrow><mi>φ</mi><mo>(</mo><mi>r</mi><mo>,</mo><mi>θ</mi><mo>,</mo><mi>T</mi><mo>(</mo><mi>t</mi><mo>)</mo><mo>)</mo></mrow></math></span> distributions were precisely visualized with a maximum relative error <span><math><mrow><mi>ζ</mi><mo>=</mo></mrow></math></span> 0.763 of space-mean <span><math><mrow><mo>〈</mo><mi>φ</mi><mo>〉</mo><mo>(</mo><mi>T</mi><mo>(</mo><mi>t</mi><mo>)</mo><mo>)</mo></mrow></math></span>, where the inhomogeneity refers to the sp","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"35 12","pages":"Article 104723"},"PeriodicalIF":4.2,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656257","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-09DOI: 10.1016/j.apt.2024.104714
Md. Obaidullah , Newaz Mohammed Bahadur , Md. Abdullah Al Nahid , Iqbal Ahmed Siddiquey , Takeshi Furusawa , Masahide Sato , Noboru Suzuki
Core-shell nanocomposites (NCs) of Fe2O3@TiO2 were synthesized using a microwave assisted sol–gel method in a relatively short time. These NCs were characterized using several techniques, including Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FE-SEM), diffuse reflectance spectroscopy (DRS), transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The TEM images showed the formation of a ∼ 4.2 nm TiO2 layer around the spherical Fe2O3 core particles. The presence of Ti 2p peaks in both the wide and narrow scan XPS spectra, along with the distinct diffraction peak in the XRD patterns, confirmed the successful synthesis of Fe2O3@TiO2 NCs. Vibration sample magnetometer (VSM) analysis showed that the NCs exhibited sufficient magnetization for catalyst separation after photocatalytic tests. The photocatalytic performance of the Fe2O3@TiO2 NCs was compared with that of uncoated Fe2O3 nanoparticles for methylene blue degradation under visible light.
{"title":"Microwave assisted sol gel synthesis of Fe2O3@TiO2 core–shell nanocomposite for the enhanced photocatalytic activity under visible light and the investigation of their optical properties","authors":"Md. Obaidullah , Newaz Mohammed Bahadur , Md. Abdullah Al Nahid , Iqbal Ahmed Siddiquey , Takeshi Furusawa , Masahide Sato , Noboru Suzuki","doi":"10.1016/j.apt.2024.104714","DOIUrl":"10.1016/j.apt.2024.104714","url":null,"abstract":"<div><div>Core-shell nanocomposites (NCs) of Fe<sub>2</sub>O<sub>3</sub>@TiO<sub>2</sub> were synthesized using a microwave assisted sol–gel method in a relatively short time. These NCs were characterized using several techniques, including Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FE-SEM), diffuse reflectance spectroscopy (DRS), transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The TEM images showed the formation of a ∼ 4.2 nm TiO<sub>2</sub> layer around the spherical Fe<sub>2</sub>O<sub>3</sub> core particles. The presence of Ti 2p peaks in both the wide and narrow scan XPS spectra, along with the distinct diffraction peak in the XRD patterns, confirmed the successful synthesis of Fe<sub>2</sub>O<sub>3</sub>@TiO<sub>2</sub> NCs. Vibration sample magnetometer (VSM) analysis showed that the NCs exhibited sufficient magnetization for catalyst separation after photocatalytic tests. The photocatalytic performance of the Fe<sub>2</sub>O<sub>3</sub>@TiO<sub>2</sub> NCs was compared with that of uncoated Fe<sub>2</sub>O<sub>3</sub> nanoparticles for methylene blue degradation under visible light.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"35 12","pages":"Article 104714"},"PeriodicalIF":4.2,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656255","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this study, sulfidation roasting was used to modify the copper ferrite to improve its flotation performance for the first time. The flotation results showed that the recovery of modified copper ferrite reached 91.63 %. The sulfidation mechanisms of copper ferrite at high temperatures were systematically investigated by X-ray diffraction (XRD) combining with thermodynamic calculations, X-ray photoelectron spectroscopy (XPS) and electron probe microanalysis (EPMA). XRD and thermodynamic analyses revealed that the CuFe2O4 was first reduced to compounds of Cu2O and Fe2O3, and was then converted to Cu2S and Fe3O4 with the increase of sulfur dosage at high temperatures. XPS analyses indicated that both the Cu2S and CuSO4 were mainly formed on the surface of mineral after the sulfidation treatment. The EPMA analyses confirmed that Cu2S was generated at the outer layer of samples after the sulfidation, while the inner part of particles was mainly composed of Fe3O4. It is concluded that the sulfidation reaction of CuFe2O4 occurred from the surface to interior during the thermal process. The sulfidation reaction pathway was devised as the follows: CuO·Fe2O3 → CuOx·Fe2O3(0 < x < 1) → Cu2O + Fe2O3 → Cu2S + Fe2O3 → Cu2S + Fe3O4 to better interpret the transformation mechanisms of CuFe2O4. These results will provide a good theoretical basis for the recovery of Cu and Fe from the refractory oxide copper resource by the combined methods of sulfidation and flotation.
{"title":"Sulfidation behavior of copper ferrite induced with sulfur and flotation responses","authors":"Yusong Huang , Yongxing Zheng , Ziqi Guo , Jinfang Lv","doi":"10.1016/j.apt.2024.104715","DOIUrl":"10.1016/j.apt.2024.104715","url":null,"abstract":"<div><div>In this study, sulfidation roasting was used to modify the copper ferrite to improve its flotation performance for the first time. The flotation results showed that the recovery of modified copper ferrite reached 91.63 %. The sulfidation mechanisms of copper ferrite at high temperatures were systematically investigated by X-ray diffraction (XRD) combining with thermodynamic calculations, X-ray photoelectron spectroscopy (XPS) and electron probe microanalysis (EPMA). XRD and thermodynamic analyses revealed that the CuFe<sub>2</sub>O<sub>4</sub> was first reduced to compounds of Cu<sub>2</sub>O and Fe<sub>2</sub>O<sub>3</sub>, and was then converted to Cu<sub>2</sub>S and Fe<sub>3</sub>O<sub>4</sub> with the increase of sulfur dosage at high temperatures. XPS analyses indicated that both the Cu<sub>2</sub>S and CuSO<sub>4</sub> were mainly formed on the surface of mineral after the sulfidation treatment. The EPMA analyses confirmed that Cu<sub>2</sub>S was generated at the outer layer of samples after the sulfidation, while the inner part of particles was mainly composed of Fe<sub>3</sub>O<sub>4</sub>. It is concluded that the sulfidation reaction of CuFe<sub>2</sub>O<sub>4</sub> occurred from the surface to interior during the thermal process. The sulfidation reaction pathway was devised as the follows: CuO·Fe<sub>2</sub>O<sub>3</sub> → CuO<sub>x</sub>·Fe<sub>2</sub>O<sub>3</sub>(0 < x < 1) → Cu<sub>2</sub>O + Fe<sub>2</sub>O<sub>3</sub> → Cu<sub>2</sub>S + Fe<sub>2</sub>O<sub>3</sub> → Cu<sub>2</sub>S + Fe<sub>3</sub>O<sub>4</sub> to better interpret the transformation mechanisms of CuFe<sub>2</sub>O<sub>4</sub>. These results will provide a good theoretical basis for the recovery of Cu and Fe from the refractory oxide copper resource by the combined methods of sulfidation and flotation.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"35 12","pages":"Article 104715"},"PeriodicalIF":4.2,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-07DOI: 10.1016/j.apt.2024.104712
Shiv Shankar , Prakash D Chavan , Sujan Saha , Gajanan Sahu , Soubhik Kumar Bhaumik
Carbon capture at elevated temperatures (200-450°C) using MgO-based solid sorbents, typically suffers from slow kinetics and premature saturation lowering the overall uptake performance. A key factor responsible for this is the agglomeration of MgCO3 during carbonation, which could be potentially overcome by the addition of inert along with promoters. In this context, this work systematically investigates the infusion of Fly ash (FA) as inert in pure MgO and alkali-salt-promoted MgO-based sorbents prepared by the sol–gel method. The study includes characterizing the prepared sorbents based on morphological and textural properties and investigating the uptake kinetics along with cyclic performance based on thermogravimetric analysis under conditions of 250°C and 300°C for 45 mins. Among all tested modified sorbents, MgO_10NaNO3_5FA exhibited the highest uptake capacity of 14.56 mmol/g (MgO basis) followed by MgO_15NaNO3 (14.27 mmol/g) at 300°C. Cyclic studies over 10 cycles reveal higher conversion of FA-infused sorbent (MgO_10NaNO3_5FA: 59.76 %) over non-FA-infused sorbent (MgO_10NaNO3: 54.50 %) showing higher stability of the former. The results establish minimal FA infusion (5 %) in alkali nitrates promoted sorbent favorable for CO2 capture at moderate temperature while elucidating physicochemical aspects during uptake.
{"title":"Infusion of fly ash in alkali salt promoted MgO-based sorbent for CO2 capture at elevated temperatures","authors":"Shiv Shankar , Prakash D Chavan , Sujan Saha , Gajanan Sahu , Soubhik Kumar Bhaumik","doi":"10.1016/j.apt.2024.104712","DOIUrl":"10.1016/j.apt.2024.104712","url":null,"abstract":"<div><div>Carbon capture at elevated temperatures (200-450°C) using MgO-based solid sorbents, typically suffers from slow kinetics and premature saturation lowering the overall uptake performance. A key factor responsible for this is the agglomeration of MgCO<sub>3</sub> during carbonation, which could be potentially overcome by the addition of inert along with promoters. In this context, this work systematically investigates the infusion of Fly ash (FA) as inert in pure MgO and alkali-salt-promoted MgO-based sorbents prepared by the sol–gel method. The study includes characterizing the prepared sorbents based on morphological and textural properties and investigating the uptake kinetics along with cyclic performance based on thermogravimetric analysis under conditions of 250°C and 300°C for 45 mins. Among all tested modified sorbents, MgO_10NaNO<sub>3</sub>_5FA exhibited the highest uptake capacity of 14.56 mmol/g (MgO basis) followed by MgO_15NaNO<sub>3</sub> (14.27 mmol/g) at 300°C.<!--> <!-->Cyclic studies over 10 cycles reveal higher conversion of FA-infused sorbent (MgO_10NaNO<sub>3</sub>_5FA: 59.76 %) over non-FA-infused sorbent (MgO_10NaNO<sub>3</sub>: 54.50 %) showing higher stability of the former. The results establish minimal FA infusion (5 %) in alkali nitrates promoted sorbent favorable for CO<sub>2</sub> capture at moderate temperature while elucidating physicochemical aspects during uptake.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"35 12","pages":"Article 104712"},"PeriodicalIF":4.2,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-06DOI: 10.1016/j.apt.2024.104713
Denis Mutebi , Frantisek Miksik , Andrew M. Spring , Indri Yaningsih , Takahiko Miyazaki , Kyaw Thu
This research reports conventionally-synthesized-zeolites with comparatively large surface area (SSA) and water-uptake prepared solely from waste-pumice. Notably, the synthesis process avoided using additional commercial raw materials, organic templates, and high temperatures, so that the process was less costly and ecofriendly. To optimize the process, the synthesis time was varied, and the mixture of the raw material and alkaline solution was stirred for 12 h. The zeolite mother liquor was also recycled. Water adsorption experiments were carried out using gravimetric measurements. The Na-P1-rich zeolite product with an optimal water uptake of 0.256 g/g was synthesized after 48 h of hydrothermal activation (H). On the other hand, the product’s optimal SSA of 186 m2/g was achieved after 36H under similar conditions (rich in faujasite). Adsorption isotherms showed that water uptake increased with activation time and with the inclusion of mother liquor recycling. Furthermore, recycling resulted in a product with enhanced SSA compared to its precursor. Un-recycled products exhibited relatively high-water uptake both at low and high relative-pressure, while the recycled product had a high uptake at high relative pressure. All products could be used in adsorption heat pump (AHP) applications (air conditioning) suited for high relative humidity (RH) environments. However, high-synthesis-time non-recycled products could also work for low RH AHP applications.
{"title":"Optimization of conventional-zeolite-synthesis from waste pumice for water adsorption","authors":"Denis Mutebi , Frantisek Miksik , Andrew M. Spring , Indri Yaningsih , Takahiko Miyazaki , Kyaw Thu","doi":"10.1016/j.apt.2024.104713","DOIUrl":"10.1016/j.apt.2024.104713","url":null,"abstract":"<div><div>This research reports conventionally-synthesized-zeolites with comparatively large surface area (SSA) and water-uptake prepared solely from waste-pumice. Notably, the synthesis process avoided using additional commercial raw materials, organic templates, and high temperatures, so that the process was less costly and ecofriendly. To optimize the process, the synthesis time was varied, and the mixture of the raw material and alkaline solution was stirred for 12 h. The zeolite mother liquor was also recycled. Water adsorption experiments were carried out using gravimetric measurements. The Na-P1-rich zeolite product with an optimal water uptake of 0.256 g/g was synthesized after 48 h of hydrothermal activation (H). On the other hand, the product’s optimal SSA of 186 m<sup>2</sup>/g was achieved after 36H under similar conditions (rich in faujasite). Adsorption isotherms showed that water uptake increased with activation time and with the inclusion of mother liquor recycling. Furthermore, recycling resulted in a product with enhanced SSA compared to its precursor. Un-recycled products exhibited relatively high-water uptake both at low and high relative-pressure, while the recycled product had a high uptake at high relative pressure. All products could be used in adsorption heat pump (AHP) applications (air conditioning) suited for high relative humidity (RH) environments. However, high-synthesis-time non-recycled products could also work for low RH AHP applications.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"35 12","pages":"Article 104713"},"PeriodicalIF":4.2,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142593192","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We found that the impact energy calculated by discrete element method (DEM) simulation can be used to explain the liberation of materials from electronic scrap (e-scrap) in a previous study; however, the absolute value of the impact energy had not been validated. Thus, we attempted to confirm the reliability by considering the particle velocity, which is highly related to impact energy. The comminution experiment was conducted using a drum-type agitation mill, and the particle velocity was measured by 3D particle tracking velocimetry (PTV) based on moving body analysis. The particle velocities for both the DEM simulation and PTV were compared for two types of particles, a non-breakable steel component and a connecting component that represents a breakable form of e-scrap. As a result, the particle velocities obtained from the two methods were within a relative error of 10% for the steel component, and thus the reliability of the impact energy was indirectly confirmed. In contrast, for the connecting component, the particle velocity from the DEM simulations was more than 50% higher, suggesting the influence of fracture energy. By calibrating the DEM simulation based on the particle velocity from PTV, the energy efficiency of fracture was estimated to be approximately 60%.
{"title":"Validation of DEM simulations for a drum-type agitation mill using particle velocities measured by 3D PTV","authors":"Takuya Tatsumoto , Yutaro Takaya , Yuki Tsunazawa , Taketoshi Koita , Keishi Oyama , Chiharu Tokoro","doi":"10.1016/j.apt.2024.104693","DOIUrl":"10.1016/j.apt.2024.104693","url":null,"abstract":"<div><div>We found that the impact energy calculated by discrete element method (DEM) simulation can be used to explain the liberation of materials from electronic scrap (e-scrap) in a previous study; however, the absolute value of the impact energy had not been validated. Thus, we attempted to confirm the reliability by considering the particle velocity, which is highly related to impact energy. The comminution experiment was conducted using a drum-type agitation mill, and the particle velocity was measured by 3D particle tracking velocimetry (PTV) based on moving body analysis. The particle velocities for both the DEM simulation and PTV were compared for two types of particles, a non-breakable steel component and a connecting component that represents a breakable form of e-scrap. As a result, the particle velocities obtained from the two methods were within a relative error of 10% for the steel component, and thus the reliability of the impact energy was indirectly confirmed. In contrast, for the connecting component, the particle velocity from the DEM simulations was more than 50% higher, suggesting the influence of fracture energy. By calibrating the DEM simulation based on the particle velocity from PTV, the energy efficiency of fracture was estimated to be approximately 60%.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"35 12","pages":"Article 104693"},"PeriodicalIF":4.2,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142578388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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