Pub Date : 2024-06-03DOI: 10.1007/s40831-024-00856-9
Miaomiao Peng, Chen Xi, Keyu Shen, Yangjing Tan, Fei Li
A novel greenness and low-cost biosorbent was prepared by polyethylene polyamine-modified waste biomass of sugarcane bagasse in this study, which was used to remove molybdenum(VI) from aqueous solution. The structural properties and adsorption mechanism of this amine-functionalized sugarcane bagasse adsorbent (SCB-A) on Mo(VI) were investigated by SEM–EDS, BET, TG, FTIR, XPS, and batch adsorption experiments. The results show that the adsorption reaction between SCB-A and Mo(VI) was a spontaneous endothermic process, and its theoretical maximum adsorption capacity was about 231.48 mg/g. The adsorption capacity was 8.93-fold compared to that of pristine sugarcane bagasse. This adsorption process was more consistent with the Langmuir model and pseudo-second-order kinetics model, indicating that this process was monolayer adsorption on a homogeneous surface and the adsorption rate was controlled by the chemisorption process. SCB-A possessed great reusability, maintaining a stable adsorption capacity after five recycles. For the adsorption toward Mo(VI), SCB-A also exhibited superior selectivity in a multi-ion coexistence solution. Therefore, SCB-A has tremendous potential in the economically and feasible removal of Mo(VI) from wastewater.
{"title":"Effective Removal of Molybdenum(VI) from Aqueous Solution Using Polyethylene Polyamine-Grafted Sugarcane Bagasse Biosorbent","authors":"Miaomiao Peng, Chen Xi, Keyu Shen, Yangjing Tan, Fei Li","doi":"10.1007/s40831-024-00856-9","DOIUrl":"https://doi.org/10.1007/s40831-024-00856-9","url":null,"abstract":"<p>A novel greenness and low-cost biosorbent was prepared by polyethylene polyamine-modified waste biomass of sugarcane bagasse in this study, which was used to remove molybdenum(VI) from aqueous solution. The structural properties and adsorption mechanism of this amine-functionalized sugarcane bagasse adsorbent (SCB-A) on Mo(VI) were investigated by SEM–EDS, BET, TG, FTIR, XPS, and batch adsorption experiments. The results show that the adsorption reaction between SCB-A and Mo(VI) was a spontaneous endothermic process, and its theoretical maximum adsorption capacity was about 231.48 mg/g. The adsorption capacity was 8.93-fold compared to that of pristine sugarcane bagasse. This adsorption process was more consistent with the Langmuir model and pseudo-second-order kinetics model, indicating that this process was monolayer adsorption on a homogeneous surface and the adsorption rate was controlled by the chemisorption process. SCB-A possessed great reusability, maintaining a stable adsorption capacity after five recycles. For the adsorption toward Mo(VI), SCB-A also exhibited superior selectivity in a multi-ion coexistence solution. Therefore, SCB-A has tremendous potential in the economically and feasible removal of Mo(VI) from wastewater.</p><h3 data-test=\"abstract-sub-heading\">Graphical Abstract</h3>\u0000","PeriodicalId":17160,"journal":{"name":"Journal of Sustainable Metallurgy","volume":"43 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141254211","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-28DOI: 10.1007/s40831-024-00848-9
Xiaoyi Cai, Wei Wang, Hongliang Zhao, Fengqin Liu, Chao Lv, Hong Yong Sohn
The lance is the heart of Top-Submerged-Lance (TSL) furnace and is also the most vulnerable part. A numerical simulation model was developed to study the TSL smelting process with a bending lance, and the effects of the bending angle on the flow field, the fluctuation and splashing, and the mean shear on the walls of the lance and the furnace body were analyzed. A VOF multi-phase model coupled with a Realizable k−ε turbulence model was adopted in this work. The simulation results reveal that the bending lance leads to asymmetrical flow field distribution, severer interface fluctuation, significantly higher slag splashing and mean shear stress on the walls of both lance and furnace body. The maximum instantaneous splashing quantity with the bending lances was increased by 33.3% compared to the vertical lance. An improvement by lance rotation on furnace operation was simulated to mitigate the effect of lance bending. Compared with the result of the original vertical lance, a smaller mean shear on the lance wall was achieved for a rotated lance.
{"title":"Numerical Simulation and Improvement of TSL Smelting Process: the Effect of Lance Bending","authors":"Xiaoyi Cai, Wei Wang, Hongliang Zhao, Fengqin Liu, Chao Lv, Hong Yong Sohn","doi":"10.1007/s40831-024-00848-9","DOIUrl":"https://doi.org/10.1007/s40831-024-00848-9","url":null,"abstract":"<p>The lance is the heart of Top-Submerged-Lance (TSL) furnace and is also the most vulnerable part. A numerical simulation model was developed to study the TSL smelting process with a bending lance, and the effects of the bending angle on the flow field, the fluctuation and splashing, and the mean shear on the walls of the lance and the furnace body were analyzed. A VOF multi-phase model coupled with a Realizable <i>k−ε</i> turbulence model was adopted in this work. The simulation results reveal that the bending lance leads to asymmetrical flow field distribution, severer interface fluctuation, significantly higher slag splashing and mean shear stress on the walls of both lance and furnace body. The maximum instantaneous splashing quantity with the bending lances was increased by 33.3% compared to the vertical lance. An improvement by lance rotation on furnace operation was simulated to mitigate the effect of lance bending. Compared with the result of the original vertical lance, a smaller mean shear on the lance wall was achieved for a rotated lance.</p><h3 data-test=\"abstract-sub-heading\">Graphical Abstract</h3>\u0000","PeriodicalId":17160,"journal":{"name":"Journal of Sustainable Metallurgy","volume":"49 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141170136","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Due to the increased demand and limited supply of nickel, the chromite overburden found in Sukinda Valley, Odisha, can be effectively utilized. This study proposes an alternative method for producing high-quality indurated pellets suitable for direct reduced iron production, which can be further smelted to obtain nickel-based alloys in an energy-efficient manner. Excellent quality pellets from low-grade ferruginous chromite overburden were obtained by optimizing various pelletization parameters, such as basicity values, induration temperatures, and duration. The optimal conditions for producing these pellets were found to be a basicity value of 1.0, an induration temperature of 1300 °C, and an induration time of 10 min. These pellets exhibited excellent metallurgical properties and can be used as a burden for subsequent DRI production. The experimental results were further corroborated by various characterization studies, including X-ray diffraction and scanning electron microscopy coupled with energy dispersion spectroscopy analyses. The study found that the recrystallization of hematite phases during the induration process improved the mechanical strength and various other properties of pellets. However, slightly higher basicity and induration parameters impaired pellet consolidation by creating cracks and forming low-melting slag phases.
Graphical Abstract
由于镍的需求增加而供应有限，可以有效利用奥迪沙邦苏金达山谷的铬铁矿覆盖层。本研究提出了一种替代方法，用于生产适用于直接还原铁生产的高质量吲哚化球团矿，这些球团矿可进一步熔炼，以节能的方式获得镍基合金。通过优化各种球团参数（如碱度值、压球温度和持续时间），从低品位铬铁矿堆积物中获得了优质球团。生产这些球团的最佳条件是碱度值为 1.0、压球温度为 1300 ℃、压球时间为 10 分钟。这些球团表现出优异的冶金特性，可用作后续 DRI 生产的原料。各种表征研究（包括 X 射线衍射和扫描电子显微镜以及能量色散光谱分析）进一步证实了实验结果。研究发现，在压延过程中赤铁矿相的再结晶提高了球团的机械强度和其他各种性能。然而，稍高的碱度和压延参数会产生裂缝并形成低熔渣相，从而影响球团的固结。
{"title":"Preparation of Nickel-Bearing Chromite Overburden Pellets Suitable for DRI Production","authors":"Nilamadhaba Sahu, Deepak Nayak, Deepak Kumar Sahu, Nilima Dash, Jeetendra Nath Panda, Ranjita Sahu, Sunil Kumar Tripathy, Gajanan U. Kapure","doi":"10.1007/s40831-024-00842-1","DOIUrl":"https://doi.org/10.1007/s40831-024-00842-1","url":null,"abstract":"<p>Due to the increased demand and limited supply of nickel, the chromite overburden found in Sukinda Valley, Odisha, can be effectively utilized. This study proposes an alternative method for producing high-quality indurated pellets suitable for direct reduced iron production, which can be further smelted to obtain nickel-based alloys in an energy-efficient manner. Excellent quality pellets from low-grade ferruginous chromite overburden were obtained by optimizing various pelletization parameters, such as basicity values, induration temperatures, and duration. The optimal conditions for producing these pellets were found to be a basicity value of 1.0, an induration temperature of 1300 °C, and an induration time of 10 min. These pellets exhibited excellent metallurgical properties and can be used as a burden for subsequent DRI production. The experimental results were further corroborated by various characterization studies, including X-ray diffraction and scanning electron microscopy coupled with energy dispersion spectroscopy analyses. The study found that the recrystallization of hematite phases during the induration process improved the mechanical strength and various other properties of pellets. However, slightly higher basicity and induration parameters impaired pellet consolidation by creating cracks and forming low-melting slag phases.</p><h3 data-test=\"abstract-sub-heading\">Graphical Abstract</h3>\u0000","PeriodicalId":17160,"journal":{"name":"Journal of Sustainable Metallurgy","volume":"66 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141170241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-20DOI: 10.1007/s40831-024-00820-7
Chris Ndoe Ya Leza Kaseba, Willie Nheta
The aim of this study was to optimize the recovery of chromite from the chrome plant tailings of the South African Middle Group chromite seams using a Wilfley shaking table. The optimization process employed the response surface methodology in conjunction with the central composite design. The independent variables considered in the investigation included the tilt angle (°), sample feed rate (g/min), table vibration (Hz), water flow rate (L/H), and particle size range (µm). On the other hand, the recovery (%), grade (% Cr2O3), Cr/Fe ratio, and separation efficiency (SE) (%) were determined as the response variables. Based on the characterization results, the sample was identified as a low-grade chromite containing 19.86% Cr2O3 and 18.12% Fe2O3 with a Cr/Fe ratio of 1.07. The bulk gangue material was well-liberated and rich in MgO (10.45%), Al2O3 (12.10%), and SiO2 (33.70%). The particle size distribution of the sample was 80% passing 106 µm. The optimal values for recovery, grade, Cr/Fe ratio and SE were found to be 71.59%, 36.97% Cr2O3, 1.52 and 30% respectively. The corresponding operating conditions were a tilt angle of 5.88°, a sample feed rate of 175 g/min, a table vibration of 44.5 Hz, a water flow rate of 366.16 L/H, and a particle size range of − 106 + 53 µm.
{"title":"Application of Response Surface Methodology on the Optimization of Chromite Recovery from the South African Middle Group Chromite Seams","authors":"Chris Ndoe Ya Leza Kaseba, Willie Nheta","doi":"10.1007/s40831-024-00820-7","DOIUrl":"https://doi.org/10.1007/s40831-024-00820-7","url":null,"abstract":"<p>The aim of this study was to optimize the recovery of chromite from the chrome plant tailings of the South African Middle Group chromite seams using a Wilfley shaking table. The optimization process employed the response surface methodology in conjunction with the central composite design. The independent variables considered in the investigation included the tilt angle (°), sample feed rate (g/min), table vibration (Hz), water flow rate (L/H), and particle size range (µm). On the other hand, the recovery (%), grade (% Cr<sub>2</sub>O<sub>3</sub>), Cr/Fe ratio, and separation efficiency (SE) (%) were determined as the response variables. Based on the characterization results, the sample was identified as a low-grade chromite containing 19.86% Cr<sub>2</sub>O<sub>3</sub> and 18.12% Fe<sub>2</sub>O<sub>3</sub> with a Cr/Fe ratio of 1.07. The bulk gangue material was well-liberated and rich in MgO (10.45%), Al<sub>2</sub>O<sub>3</sub> (12.10%), and SiO<sub>2</sub> (33.70%). The particle size distribution of the sample was 80% passing 106 µm. The optimal values for recovery, grade, Cr/Fe ratio and SE were found to be 71.59%, 36.97% Cr<sub>2</sub>O<sub>3</sub>, 1.52 and 30% respectively. The corresponding operating conditions were a tilt angle of 5.88°, a sample feed rate of 175 g/min, a table vibration of 44.5 Hz, a water flow rate of 366.16 L/H, and a particle size range of − 106 + 53 µm.</p><h3 data-test=\"abstract-sub-heading\">Graphical Abstract</h3>\u0000","PeriodicalId":17160,"journal":{"name":"Journal of Sustainable Metallurgy","volume":"14 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141150187","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-17DOI: 10.1007/s40831-024-00844-z
L. Jiang, R. K. W. Marceau, T. Dorin
Recycled aluminum alloys are pivotal for sustainable manufacturing, offering strength, durability, and environmental advantages. However, the presence of iron (Fe) impurities poses a major challenge, undermining their properties and recyclability. Conventional manufacturing processes result in coarse Fe-rich intermetallic compounds that limit the tolerance of Fe content and negatively influence performance of advanced aluminum alloys. To address this, rapid solidification techniques like direct strip casting have been explored. In this work, a detailed study of the strip cast microstructure was conducted by scanning electron microscopy, electron backscattered diffraction and atom probe tomography. Our results reveal that alloys produced by direct strip casting exhibit significantly refined microstructures and are free from coarse Fe-rich intermetallics, thereby retaining the majority of Fe in solid solution. These findings indicate that strip casting significantly enhances Fe-tolerance in aluminum alloys, making it an attractive process for future aluminum recycling, with implications for sustainable high-performance applications.
{"title":"Improved Iron-Tolerance in Recycled Aluminum Alloys via Direct Strip Casting Process","authors":"L. Jiang, R. K. W. Marceau, T. Dorin","doi":"10.1007/s40831-024-00844-z","DOIUrl":"https://doi.org/10.1007/s40831-024-00844-z","url":null,"abstract":"<p>Recycled aluminum alloys are pivotal for sustainable manufacturing, offering strength, durability, and environmental advantages. However, the presence of iron (Fe) impurities poses a major challenge, undermining their properties and recyclability. Conventional manufacturing processes result in coarse Fe-rich intermetallic compounds that limit the tolerance of Fe content and negatively influence performance of advanced aluminum alloys. To address this, rapid solidification techniques like direct strip casting have been explored. In this work, a detailed study of the strip cast microstructure was conducted by scanning electron microscopy, electron backscattered diffraction and atom probe tomography. Our results reveal that alloys produced by direct strip casting exhibit significantly refined microstructures and are free from coarse Fe-rich intermetallics, thereby retaining the majority of Fe in solid solution. These findings indicate that strip casting significantly enhances Fe-tolerance in aluminum alloys, making it an attractive process for future aluminum recycling, with implications for sustainable high-performance applications.</p><h3 data-test=\"abstract-sub-heading\">Graphical Abstract</h3>","PeriodicalId":17160,"journal":{"name":"Journal of Sustainable Metallurgy","volume":"54 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141063083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-09DOI: 10.1007/s40831-024-00788-4
Yannan Wang, Min Gan, Xiaohui Fan, Zhiyun Ji, Wei Lv, Ganesh Pilla, Mingfeng Ye
In this study, a mixture rich in K, Na, and Pb, composed of undesired elements rich iron ore A, sinter dust, and blast furnace dust (ore-dust mix,), is sintered along with the regular iron ore. The K, Na, and Pb compounds within the ore-dust mix are identified as alkali chlorides, alkali aluminosilicates, PbO, and PbSO4 using X-ray diffraction. The primary objective is to investigate the impact of three distinct sintering technologies: regular (pre-reduction) sintering, double-layer sintering, and hearth-layer sintering, on the removal degrees of K, Na, and Pb. In both the regular and double-layer sintering processes, the K, Na, and Pb contents within the blend of raw materials was measured approximately 0.430 wt%, 0.105 wt%, and 0.033 wt%, respectively. Moreover, the ratio of ore-dust mix to the regular ore was 0.54. In the regular sinter pot test, sinter feed was uniformly placed in the pot. In the run of the regular sinter pot test with the optimal coke breeze ratio of 20 wt%, the removal degrees of K, Na, and Pb were 79.5%, 67.5% and 92.7%, respectively. In comparison, the double-layer sintering technology resulted in a slight increase in the removal degrees for alkali metals and a similar removal degree for Pb, while utilizing a reduced coke breeze ratio of only 8.10 wt%. The removal mechanism of the hearth-layer and double-layer sintering processes are similar. However, the coke breeze ratio decreases to 6.63 wt% as the fraction of ore-dust mix within the blend of raw materials is reduced to 7 wt% during the hearth-layer sintering process.
{"title":"Enhanced Removal of Potassium, Sodium, and Lead During the Iron Ore Sintering Process","authors":"Yannan Wang, Min Gan, Xiaohui Fan, Zhiyun Ji, Wei Lv, Ganesh Pilla, Mingfeng Ye","doi":"10.1007/s40831-024-00788-4","DOIUrl":"https://doi.org/10.1007/s40831-024-00788-4","url":null,"abstract":"<p>In this study, a mixture rich in K, Na, and Pb, composed of undesired elements rich iron ore A, sinter dust, and blast furnace dust (ore-dust mix,), is sintered along with the regular iron ore. The K, Na, and Pb compounds within the ore-dust mix are identified as alkali chlorides, alkali aluminosilicates, PbO, and PbSO<sub>4</sub> using X-ray diffraction. The primary objective is to investigate the impact of three distinct sintering technologies: regular (pre-reduction) sintering, double-layer sintering, and hearth-layer sintering, on the removal degrees of K, Na, and Pb. In both the regular and double-layer sintering processes, the K, Na, and Pb contents within the blend of raw materials was measured approximately 0.430 wt%, 0.105 wt%, and 0.033 wt%, respectively. Moreover, the ratio of ore-dust mix to the regular ore was 0.54. In the regular sinter pot test, sinter feed was uniformly placed in the pot. In the run of the regular sinter pot test with the optimal coke breeze ratio of 20 wt%, the removal degrees of K, Na, and Pb were 79.5%, 67.5% and 92.7%, respectively. In comparison, the double-layer sintering technology resulted in a slight increase in the removal degrees for alkali metals and a similar removal degree for Pb, while utilizing a reduced coke breeze ratio of only 8.10 wt%. The removal mechanism of the hearth-layer and double-layer sintering processes are similar. However, the coke breeze ratio decreases to 6.63 wt% as the fraction of ore-dust mix within the blend of raw materials is reduced to 7 wt% during the hearth-layer sintering process.</p><h3 data-test=\"abstract-sub-heading\">Graphical Abstract</h3>","PeriodicalId":17160,"journal":{"name":"Journal of Sustainable Metallurgy","volume":"155 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140929214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The reclamation of exhausted Fluid Catalytic Cracking (FCC) catalysts has attracted considerable interest. However, the leaching rates of valuable metals in waste can be influenced by the pretreatment and calcination process. This study focuses on investigating the impact of pretreatment temperature on the metal-leaching process of spent FCC catalysts. After calcination at 1200 °C, the Al2O3 carrier transformed from γ-Al2O3 to α-Al2O3 with a denser structure. Subsequently, the valuable metals react with the carrier to form regular acid salts, which are averse to the leaching process. While the pretreatment roasting of spent FCC catalysts at 600 °C could not only remove the surface impurities effectively but also keep the original γ-Al2O3 structure, promoting the leaching process. Finally, the kinetic model is studied with the aim of achieving the high-efficiency leaching of Ni in spent FCC catalysts. The leaching kinetics model of Ni accords with the ash diffusion model, and the reaction activation energy is 53.05 kJ/mol, in the temperature range of 60–90 °C, sulfuric acid concentration of 2 mol/L, particle size of less than 200 mesh (75μm). Specifically, for spent FCC catalysts, pretreatment at high temperatures is not conducive to subsequent leaching, while pretreatment at low temperatures is conducive to subsequent leaching of valuable metals.
Graphical Abstract
流化催化裂化（FCC）催化剂用完后的回收利用引起了人们的极大兴趣。然而，废料中有价金属的浸出率会受到预处理和煅烧过程的影响。本研究主要探讨预处理温度对催化裂化废催化剂金属浸出过程的影响。在 1200 °C 煅烧后，Al2O3 载体从 γ-Al2O3 转变为结构更致密的 α-Al2O3。随后，有价金属会与载体发生反应，形成对浸出过程不利的常规酸盐。而对废催化裂化催化剂进行 600 °C 的预处理焙烧，不仅能有效去除表面杂质，还能保持原有的 γ-Al2O3 结构，促进浸出过程。最后，研究了动力学模型，以期实现废催化裂化催化剂中 Ni 的高效浸出。镍的浸出动力学模型符合灰扩散模型，在温度为 60-90 ℃、硫酸浓度为 2 mol/L、粒度小于 200 目（75μm）的条件下，反应活化能为 53.05 kJ/mol。具体而言，对于催化裂化废催化剂，高温预处理不利于后续浸出，而低温预处理则有利于后续有价金属的浸出。
{"title":"Study on Pretreatment and Leaching Behaviors of Spent Fluid Catalytic Cracking Catalysts","authors":"Mingshuai Wu, Wenbo Cheng, Fengshan Yu, Maolin Tian, Xueli Wang, Yongjie Bu, Jiawei Wen, Guoyong Huang","doi":"10.1007/s40831-024-00831-4","DOIUrl":"https://doi.org/10.1007/s40831-024-00831-4","url":null,"abstract":"<p>The reclamation of exhausted Fluid Catalytic Cracking (FCC) catalysts has attracted considerable interest. However, the leaching rates of valuable metals in waste can be influenced by the pretreatment and calcination process. This study focuses on investigating the impact of pretreatment temperature on the metal-leaching process of spent FCC catalysts. After calcination at 1200 °C, the Al<sub>2</sub>O<sub>3</sub> carrier transformed from γ-Al<sub>2</sub>O<sub>3</sub> to α-Al<sub>2</sub>O<sub>3</sub> with a denser structure. Subsequently, the valuable metals react with the carrier to form regular acid salts, which are averse to the leaching process. While the pretreatment roasting of spent FCC catalysts at 600 °C could not only remove the surface impurities effectively but also keep the original γ-Al<sub>2</sub>O<sub>3</sub> structure, promoting the leaching process. Finally, the kinetic model is studied with the aim of achieving the high-efficiency leaching of Ni in spent FCC catalysts. The leaching kinetics model of Ni accords with the ash diffusion model, and the reaction activation energy is 53.05 kJ/mol, in the temperature range of 60–90 °C, sulfuric acid concentration of 2 mol/L, particle size of less than 200 mesh (75μm). Specifically, for spent FCC catalysts, pretreatment at high temperatures is not conducive to subsequent leaching, while pretreatment at low temperatures is conducive to subsequent leaching of valuable metals.</p><h3 data-test=\"abstract-sub-heading\">Graphical Abstract</h3>\u0000","PeriodicalId":17160,"journal":{"name":"Journal of Sustainable Metallurgy","volume":"22 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140929382","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-08DOI: 10.1007/s40831-024-00834-1
Mustapha A. Raji, Alafara A. Baba, Abhilash, Ajeet Gangwar, Jude O. Majasan
The continuous rise of the population cum standard of living has resulted in Nigerians looking for a profound solution to the fast-growing demand for electrical energy with sustainability concerns including greenhouse gas emissions limitation. Thus, the investigation of uranium leaching kinetics and thermodynamics has become one of the most crucial topics in leach technology, where many distinct results have been obtained. In this study, the influence of sulfuric acid concentration, reaction temperature, solid-to-liquid ratio, and leaching time were all investigated. At established experimental conditions (2.5 mol/L H2SO4, 75 °C, 75 µm), the uranium ore dissolution efficiency recorded was 89.1% within 120 min. The kinetic and thermodynamic tests of the leaching process coupled with the reaction mechanism between sulfuric acid and uranium were discussed. Hence, the results confirm that the dissolution mechanism of uranium was diffusion controlled, exothermic, and spontaneous.
{"title":"Optimization of the Leaching Kinetics for Uranium Recovery from a Boltwoodite Ore as Emerging Solution to Nigerian Power Sector","authors":"Mustapha A. Raji, Alafara A. Baba, Abhilash, Ajeet Gangwar, Jude O. Majasan","doi":"10.1007/s40831-024-00834-1","DOIUrl":"https://doi.org/10.1007/s40831-024-00834-1","url":null,"abstract":"<p>The continuous rise of the population <i>cum</i> standard of living has resulted in Nigerians looking for a profound solution to the fast-growing demand for electrical energy with sustainability concerns including greenhouse gas emissions limitation. Thus, the investigation of uranium leaching kinetics and thermodynamics has become one of the most crucial topics in leach technology, where many distinct results have been obtained. In this study, the influence of sulfuric acid concentration, reaction temperature, solid-to-liquid ratio, and leaching time were all investigated. At established experimental conditions (2.5 mol/L H<sub>2</sub>SO<sub>4</sub>, 75 °C, 75 µm), the uranium ore dissolution efficiency recorded was 89.1% within 120 min. The kinetic and thermodynamic tests of the leaching process coupled with the reaction mechanism between sulfuric acid and uranium were discussed. Hence, the results confirm that the dissolution mechanism of uranium was diffusion controlled, exothermic, and spontaneous.</p><h3 data-test=\"abstract-sub-heading\">Graphical Abstract</h3>","PeriodicalId":17160,"journal":{"name":"Journal of Sustainable Metallurgy","volume":"128 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140929097","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rapid development of the fluorine industry has led to mass production of fluorine-containing waste, and direct discharge of this waste will cause serious environmental pollution of water, atmosphere, soil, and so on. Recycling and treatment of fluorine-containing waste are required for environmental protection and to utilize the fluorine resources. Because of decreases in fluorite reserves and inefficient fluorine resource recovery, cryolite has become a potential resource for fluorine recovery. This paper summarizes research on the preparation of cryolite from fluorine-containing substances produced in various industries, mechanisms of contamination under different conditions, and commonly used methods for controlling the product particle size. The results indicate that cryolite prepared in acidic or weakly alkaline solutions with a fluorine–aluminum molar ratio of 5.4–6.6 has high purity. The particle size of the cryolite increases with the addition of a seed during precipitation. This review provides insight for future production of cryolite with regard to purity problems and particle size control.
{"title":"Review on the Preparation of Cryolite from Industry Waste Containing Fluorine","authors":"Xiaomeng Cao, Jianping Peng, Wenxiong Dong, Yifei Li, Yaowu Wang, Yuezhong Di","doi":"10.1007/s40831-024-00835-0","DOIUrl":"https://doi.org/10.1007/s40831-024-00835-0","url":null,"abstract":"<p>Rapid development of the fluorine industry has led to mass production of fluorine-containing waste, and direct discharge of this waste will cause serious environmental pollution of water, atmosphere, soil, and so on. Recycling and treatment of fluorine-containing waste are required for environmental protection and to utilize the fluorine resources. Because of decreases in fluorite reserves and inefficient fluorine resource recovery, cryolite has become a potential resource for fluorine recovery. This paper summarizes research on the preparation of cryolite from fluorine-containing substances produced in various industries, mechanisms of contamination under different conditions, and commonly used methods for controlling the product particle size. The results indicate that cryolite prepared in acidic or weakly alkaline solutions with a fluorine–aluminum molar ratio of 5.4–6.6 has high purity. The particle size of the cryolite increases with the addition of a seed during precipitation. This review provides insight for future production of cryolite with regard to purity problems and particle size control.</p><h3 data-test=\"abstract-sub-heading\">Graphical Abstract</h3>\u0000","PeriodicalId":17160,"journal":{"name":"Journal of Sustainable Metallurgy","volume":"21 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140929105","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-08DOI: 10.1007/s40831-024-00836-z
Han Zhang, Ke Liu, Hongxin Zhao, Yue Tian, Jianye Liang, Zhangfu Yuan
The innovative slag splashing technology can significantly reduce CO2 emissions in the steel industry. However, conventional oxygen lances are no longer sufficient due to the gas-slag reactions involved. Hence, the feasibility of applying nozzle-twisted oxygen lances to the innovative slag splashing process was investigated in this work. Numerical simulation was employed to compare the CO2 jet, its impact characteristics on the slag, and the slag splashing performance of both the nozzle-twisted and conventional oxygen lances. It was found that the nozzle-twisted jet has higher radial and tangential velocities and a more significant impact region compared with the conventional jet. Furthermore, it exhibited superior stirring capability for the melt pool, enhancing the average velocity of the slag and reducing the size of dead zones. This facilitated the mixing of carbon powder and the interfacial reaction between CO2 and the slag. However, the slag splashing performance deteriorated after the oxygen lance was replaced. Fortunately, the slag still reached the vicinity of the slag line. Furthermore, the addition of bottom blowing compensated for the disadvantages, elevating the slag mass flow rate and further enhancing the stirring of the slag. Therefore, utilizing nozzle-twisted oxygen lances is feasible in this scenario.
{"title":"Numerical Simulation of Innovative Slag Splashing Process in a Converter Using a Nozzle-Twisted Oxygen Lance","authors":"Han Zhang, Ke Liu, Hongxin Zhao, Yue Tian, Jianye Liang, Zhangfu Yuan","doi":"10.1007/s40831-024-00836-z","DOIUrl":"https://doi.org/10.1007/s40831-024-00836-z","url":null,"abstract":"<p>The innovative slag splashing technology can significantly reduce CO<sub>2</sub> emissions in the steel industry. However, conventional oxygen lances are no longer sufficient due to the gas-slag reactions involved. Hence, the feasibility of applying nozzle-twisted oxygen lances to the innovative slag splashing process was investigated in this work. Numerical simulation was employed to compare the CO<sub>2</sub> jet, its impact characteristics on the slag, and the slag splashing performance of both the nozzle-twisted and conventional oxygen lances. It was found that the nozzle-twisted jet has higher radial and tangential velocities and a more significant impact region compared with the conventional jet. Furthermore, it exhibited superior stirring capability for the melt pool, enhancing the average velocity of the slag and reducing the size of dead zones. This facilitated the mixing of carbon powder and the interfacial reaction between CO<sub>2</sub> and the slag. However, the slag splashing performance deteriorated after the oxygen lance was replaced. Fortunately, the slag still reached the vicinity of the slag line. Furthermore, the addition of bottom blowing compensated for the disadvantages, elevating the slag mass flow rate and further enhancing the stirring of the slag. Therefore, utilizing nozzle-twisted oxygen lances is feasible in this scenario.</p><h3 data-test=\"abstract-sub-heading\">Graphical Abstract</h3>\u0000","PeriodicalId":17160,"journal":{"name":"Journal of Sustainable Metallurgy","volume":"16 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140929386","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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