Pub Date : 2025-02-04DOI: 10.1016/j.psep.2025.106864
Gokulkumar Sivanantham , Divya Divakaran , Indran Suyambulingam , G. Suganya Priyadharshini , Yamuna Munusamy , Adhigan Murali , Sung Soo Han
This study addresses the global demand for sustainable materials by isolating and characterizing microcrystalline cellulose (MCC) from rice stalk agro-waste and applying it to enhance the mechanical properties of poly(butylene adipate-co-terephthalate) (PBAT) biofilms. Rice stalk MCC (RSMCC) was extracted using chemical treatments, including alkalization, acid hydrolysis, and bleaching. The extracted MCC was characterized by Fourier-transform infrared spectroscopy (FTIR), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), atomic force microscopy (AFM), UV–visible spectroscopy, and thermogravimetric analysis (TGA). RSMCC was incorporated into the PBAT films at 0–5 wt% concentrations using the solution casting method, and the biofilms' mechanical properties were evaluated. RSMCC exhibited a crystallinity index of 75.75 %, thermal stability up to 200 °C, and an average particle size of 134.068 µm. Incorporating 4 wt% RSMCC into PBAT achieved the highest tensile strength (28.16 MPa) and modulus (15.92 MPa). The results demonstrated RSMCC's effectiveness of RSMCC as a reinforcing agent, enhancing the mechanical and thermal properties of PBAT biofilms. These findings support RSMCC's potential of RSMCC for the development of biodegradable and sustainable packaging materials.
{"title":"Isolation and characterization of microcrystalline cellulose from rice stalk agro-waste and its application in enhancing inherent properties of PBAT biofilm","authors":"Gokulkumar Sivanantham , Divya Divakaran , Indran Suyambulingam , G. Suganya Priyadharshini , Yamuna Munusamy , Adhigan Murali , Sung Soo Han","doi":"10.1016/j.psep.2025.106864","DOIUrl":"10.1016/j.psep.2025.106864","url":null,"abstract":"<div><div>This study addresses the global demand for sustainable materials by isolating and characterizing microcrystalline cellulose (MCC) from rice stalk agro-waste and applying it to enhance the mechanical properties of poly(butylene adipate-co-terephthalate) (PBAT) biofilms. Rice stalk MCC (RSMCC) was extracted using chemical treatments, including alkalization, acid hydrolysis, and bleaching. The extracted MCC was characterized by Fourier-transform infrared spectroscopy (FTIR), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), atomic force microscopy (AFM), UV–visible spectroscopy, and thermogravimetric analysis (TGA). RSMCC was incorporated into the PBAT films at 0–5 wt% concentrations using the solution casting method, and the biofilms' mechanical properties were evaluated. RSMCC exhibited a crystallinity index of 75.75 %, thermal stability up to 200 °C, and an average particle size of 134.068 µm. Incorporating 4 wt% RSMCC into PBAT achieved the highest tensile strength (28.16 MPa) and modulus (15.92 MPa). The results demonstrated RSMCC's effectiveness of RSMCC as a reinforcing agent, enhancing the mechanical and thermal properties of PBAT biofilms. These findings support RSMCC's potential of RSMCC for the development of biodegradable and sustainable packaging materials.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"196 ","pages":"Article 106864"},"PeriodicalIF":6.9,"publicationDate":"2025-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143387952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-04DOI: 10.1016/j.psep.2025.106856
Fengping Yu , Jingtian Gao , Peng Zhang , Shike Tang , Hongjie Liu , Weiping Li
Metal oxide nanoparticles (MONPs) are inevitably released into environment during the life cycle. Transformation processes of MONPs such as aggregation, deposition, and dissolution in environment will dominate the occurrence forms. Occurrence forms of MONPs will influence their mobility, bioavailability, and toxicity. Transformation of MONPs under the impact of pH, ionic strength (IS), and natural organic matter (NOM) are summarized to thoroughly identify environmental behavior of MONPs. The effect of MONPs on physiological and biochemical properties of microalgae in freshwater systems are discussed, and the toxicity mechanisms of MONPs were analyzed. The relationship between transformed occurrence forms of MONPs and their ecotoxicity caused by the variation of water quality factors is emphasized. Noteworthily, the transformation pathway of MONPs under the influence of environmental factors is uncertain, which makes it difficult to predict their occurrence forms in surface waters. Therefore, it's crucial to consider the combined impact of these factors on MONPs behavior in natural aquatic environment. Overall, this review aims to enhance the comprehension of their environmental risks in aquatic settings and establish a scientific foundation for the sustainable progression of nanotechnology.
{"title":"Distribution, environmental behavior, and ecotoxicity of different metal oxide nanoparticles in the aquatic environment","authors":"Fengping Yu , Jingtian Gao , Peng Zhang , Shike Tang , Hongjie Liu , Weiping Li","doi":"10.1016/j.psep.2025.106856","DOIUrl":"10.1016/j.psep.2025.106856","url":null,"abstract":"<div><div>Metal oxide nanoparticles (MONPs) are inevitably released into environment during the life cycle. Transformation processes of MONPs such as aggregation, deposition, and dissolution in environment will dominate the occurrence forms. Occurrence forms of MONPs will influence their mobility, bioavailability, and toxicity. Transformation of MONPs under the impact of pH, ionic strength (IS), and natural organic matter (NOM) are summarized to thoroughly identify environmental behavior of MONPs. The effect of MONPs on physiological and biochemical properties of microalgae in freshwater systems are discussed, and the toxicity mechanisms of MONPs were analyzed. The relationship between transformed occurrence forms of MONPs and their ecotoxicity caused by the variation of water quality factors is emphasized. Noteworthily, the transformation pathway of MONPs under the influence of environmental factors is uncertain, which makes it difficult to predict their occurrence forms in surface waters. Therefore, it's crucial to consider the combined impact of these factors on MONPs behavior in natural aquatic environment. Overall, this review aims to enhance the comprehension of their environmental risks in aquatic settings and establish a scientific foundation for the sustainable progression of nanotechnology.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"196 ","pages":"Article 106856"},"PeriodicalIF":6.9,"publicationDate":"2025-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143259520","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-04DOI: 10.1016/j.psep.2025.106858
Wen Nie , Mingyuan Lu , Lidian Guo , Huitian Peng , Jiuchao Li , Ao Tang , Heng Liu , Jinkun Zhang
Coal mining machine cutting is one of the primary sources of dust generation in coal mines, Serious threat to the occupational health of workers. To address this issue, a novel hydraulic rotary wind-spray control combined dust reduction device was developed for reduce coal cutting dust production. The device's design features different types of air duct structures to ensure adequate airflow for dust control. By adjusting the spray pressure and angle, the system generates a high-quality spray field to effectively capture dust produced during coal cutting.The study found that shifting the spray nozzle along the cutting direction toward the coal wall achieved optimal dust suppression at specific angles: a 25° offset at the front drum and a 15° offset at the rear drum, with a spray pressure set at 6 MPa. Under these conditions, the system demonstrated significant dust reduction. Field application of the innovative device resulted in a decrease in dust concentration to 39.3 mg/m³ , achieving a dust suppression efficiency of 89.74 %, indicating an ideal dust control outcome.
{"title":"Study on a novel hydraulic rotary wind-spray control combined dust reduction device for shearer","authors":"Wen Nie , Mingyuan Lu , Lidian Guo , Huitian Peng , Jiuchao Li , Ao Tang , Heng Liu , Jinkun Zhang","doi":"10.1016/j.psep.2025.106858","DOIUrl":"10.1016/j.psep.2025.106858","url":null,"abstract":"<div><div>Coal mining machine cutting is one of the primary sources of dust generation in coal mines, Serious threat to the occupational health of workers. To address this issue, a novel hydraulic rotary wind-spray control combined dust reduction device was developed for reduce coal cutting dust production. The device's design features different types of air duct structures to ensure adequate airflow for dust control. By adjusting the spray pressure and angle, the system generates a high-quality spray field to effectively capture dust produced during coal cutting.The study found that shifting the spray nozzle along the cutting direction toward the coal wall achieved optimal dust suppression at specific angles: a 25° offset at the front drum and a 15° offset at the rear drum, with a spray pressure set at 6 MPa. Under these conditions, the system demonstrated significant dust reduction. Field application of the innovative device resulted in a decrease in dust concentration to 39.3 mg/m³ , achieving a dust suppression efficiency of 89.74 %, indicating an ideal dust control outcome.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"196 ","pages":"Article 106858"},"PeriodicalIF":6.9,"publicationDate":"2025-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143376925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Small water supply systems provide safe drinking water to small communities. This study developed, built, and tested a self-sustained small water supply system with an annual capacity of 1000 m³ , using 20 surface-modified PTFE membranes for a total filtration area of 1.42 m². The system includes a settling tank, membrane module, filtrate tank, chemical tank, pumps, pipes, and a control panel. It was installed and operated in a remote site of northern Taiwan for 242 days, even during power outages and typhoons. Operational and maintenance costs for small water supply systems can be high due to extensive chemical use and workforce demands, while ensuring the reliability of these systems is also a public health and safety challenge. Long-term tests showed the present system produced quality drinking water without coagulants or disinfectants, significantly reducing chemical costs. The system was self-sustained with minimal maintenance, lowering workforce costs. It achieved a water production cost of 0.18 USD/m³ , much lower than the tariffs in most countries.
{"title":"Automatic small water supply system for remote areas with plasma-modified poly(tetrafluoroethylene) membranes","authors":"Ying-Ju Chang , Jo-Shu Chang , Duu-Jong Lee , Chihpin Huang","doi":"10.1016/j.psep.2025.106857","DOIUrl":"10.1016/j.psep.2025.106857","url":null,"abstract":"<div><div>Small water supply systems provide safe drinking water to small communities. This study developed, built, and tested a self-sustained small water supply system with an annual capacity of 1000 m³ , using 20 surface-modified PTFE membranes for a total filtration area of 1.42 m². The system includes a settling tank, membrane module, filtrate tank, chemical tank, pumps, pipes, and a control panel. It was installed and operated in a remote site of northern Taiwan for 242 days, even during power outages and typhoons. Operational and maintenance costs for small water supply systems can be high due to extensive chemical use and workforce demands, while ensuring the reliability of these systems is also a public health and safety challenge. Long-term tests showed the present system produced quality drinking water without coagulants or disinfectants, significantly reducing chemical costs. The system was self-sustained with minimal maintenance, lowering workforce costs. It achieved a water production cost of 0.18 USD/m³ , much lower than the tariffs in most countries.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"196 ","pages":"Article 106857"},"PeriodicalIF":6.9,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143394094","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-03DOI: 10.1016/j.psep.2025.106855
Hongguang Pan , Yubiao Fan , Jun Deng , Keke Shi , Caiping Wang , Xinyu Lei , Zechen Wei , Junming Bai
Accurately predicting coal spontaneous combustion temperature is crucial for preventing coal mine fires, reducing loss of life, and safeguarding property. Traditional gas concentration prediction methods typically rely on a limited set of gas concentration parameters, often neglecting the complex interactions among them, which impacts prediction accuracy. In this study, we propose a prediction model based on Graph Convolutional Network (GCN), which integrates gas concentration parameters and their interactions to enhance prediction performance. First, the parameters are represented as nodes in a directed graph, with edges defined by the chemical reactions occurring during the coal self-heating process. Then, multiple GCN layers are employed to capture the intricate relationships between the nodes. The model was trained and tested on datasets from multiple coal mines, and the results demonstrate that the GCN model outperforms existing methods. Specifically, for datasets from different coal samples, the MAE values are 2.49, 3.53, and 2.92, while the R2 values for all datasets exceed 0.99. This demonstrates that considering the interrelationships between different gas indicators significantly improves the accuracy of coal spontaneous combustion temperature prediction, validating the effectiveness of the proposed method and contributing to reducing the occurrence of coal mine spontaneous combustion disasters.
{"title":"GCN-based prediction method for coal spontaneous combustion temperature","authors":"Hongguang Pan , Yubiao Fan , Jun Deng , Keke Shi , Caiping Wang , Xinyu Lei , Zechen Wei , Junming Bai","doi":"10.1016/j.psep.2025.106855","DOIUrl":"10.1016/j.psep.2025.106855","url":null,"abstract":"<div><div>Accurately predicting coal spontaneous combustion temperature is crucial for preventing coal mine fires, reducing loss of life, and safeguarding property. Traditional gas concentration prediction methods typically rely on a limited set of gas concentration parameters, often neglecting the complex interactions among them, which impacts prediction accuracy. In this study, we propose a prediction model based on Graph Convolutional Network (GCN), which integrates gas concentration parameters and their interactions to enhance prediction performance. First, the parameters are represented as nodes in a directed graph, with edges defined by the chemical reactions occurring during the coal self-heating process. Then, multiple GCN layers are employed to capture the intricate relationships between the nodes. The model was trained and tested on datasets from multiple coal mines, and the results demonstrate that the GCN model outperforms existing methods. Specifically, for datasets from different coal samples, the MAE values are 2.49, 3.53, and 2.92, while the R<sup>2</sup> values for all datasets exceed 0.99. This demonstrates that considering the interrelationships between different gas indicators significantly improves the accuracy of coal spontaneous combustion temperature prediction, validating the effectiveness of the proposed method and contributing to reducing the occurrence of coal mine spontaneous combustion disasters.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"196 ","pages":"Article 106855"},"PeriodicalIF":6.9,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143349133","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-01DOI: 10.1016/j.psep.2024.12.015
Sivan Klas , Idan Rom
Extensive studies have focused on precipitative recovery of magnesium from seawater desalination concentrate, but much less from brackish groundwater desalination concentrate (BWDC). The current work investigated the feasibility of a new three step process for complete Ca and Mg removal from BWDC, to enhance water recovery, while producing pure CaCO3 and Mg(OH)2 to offset treatment costs. Step 1 involved BWDC aeration softening, which was tested in a continuous crystallizer at different water and air flowrates, using intrinsic crystallization seed. Subsequent steps (2 and 3) involved NaOH or Na2CO3 addition to 24 h aerated BWDC under batch mode and precipitates recovery. Aeration energy estimation in step 1 indicated an exponential decrease from 2.25 to 0.25 kWh m−3BWDC, and respective Ca removal decrease from 97 % to 60 % with respect to equilibrium. Ca removal in the complete process reached 95.6 % - 99.5 % while Mg removal was 91 % and 98 % when pH reached 10.7 and 11.2, respectively. CaCO3 polymorphs were the only detected solid phases using NaOH in step 2, whereas CaMg(CO3)2 was also detected using Na2CO3. The precipitates recovered in step 3 contained 99 % Mg(OH)2. Overall base consumption was 1.85 and 2.21 mols per mols of removed Ca and Mg, using NaOH and Na2CO3 in step 2, respectively. Hydraulic retention times of 1 – 2 h during step 1 was shown to potentially minimize overall process costs.
{"title":"Three-step precipitation process for calcium and magnesium recovery from brackish groundwater desalination concentrate","authors":"Sivan Klas , Idan Rom","doi":"10.1016/j.psep.2024.12.015","DOIUrl":"10.1016/j.psep.2024.12.015","url":null,"abstract":"<div><div>Extensive studies have focused on precipitative recovery of magnesium from seawater desalination concentrate, but much less from brackish groundwater desalination concentrate (BWDC). The current work investigated the feasibility of a new three step process for complete Ca and Mg removal from BWDC, to enhance water recovery, while producing pure CaCO<sub>3</sub> and Mg(OH)<sub>2</sub> to offset treatment costs. Step 1 involved BWDC aeration softening, which was tested in a continuous crystallizer at different water and air flowrates, using intrinsic crystallization seed. Subsequent steps (2 and 3) involved NaOH or Na<sub>2</sub>CO<sub>3</sub> addition to 24 h aerated BWDC under batch mode and precipitates recovery. Aeration energy estimation in step 1 indicated an exponential decrease from 2.25 to 0.25 kWh m<sup>−3</sup><sub>BWDC</sub>, and respective Ca removal decrease from 97 % to 60 % with respect to equilibrium. Ca removal in the complete process reached 95.6 % - 99.5 % while Mg removal was 91 % and 98 % when pH reached 10.7 and 11.2, respectively. CaCO<sub>3</sub> polymorphs were the only detected solid phases using NaOH in step 2, whereas CaMg(CO<sub>3</sub>)<sub>2</sub> was also detected using Na<sub>2</sub>CO<sub>3</sub>. The precipitates recovered in step 3 contained 99 % Mg(OH)<sub>2.</sub> Overall base consumption was 1.85 and 2.21 mols per mols of removed Ca and Mg, using NaOH and Na<sub>2</sub>CO<sub>3</sub> in step 2, respectively. Hydraulic retention times of 1 – 2 h during step 1 was shown to potentially minimize overall process costs.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"194 ","pages":"Pages 129-138"},"PeriodicalIF":6.9,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142821111","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-01DOI: 10.1016/j.psep.2024.12.009
Gaofeng Fan , Xinyue Gao , Chang’an Wang , Yujie Hou , Jinming Zhang , Jie Xu , Defu Che
Efficient utilization of low-grade waste heat is pivotal for advancing energy savings and emissions reduction in power stations. However, the heat and water contained in flue gas and slurry post wet flue gas desulfurization (WFGD) have traditionally been underutilized. The flash-heat pump-heat exchanger (FHH) system and heat exchanger-heat pump (HH) system were proposed, employing heat exchangers (HE), flash column (FC), and absorption heat pumps (AHP) to utilize waste heat for seasonal heating and air heating purposes. A comprehensive evaluation of the systems was conducted, encompassing thermal performance, exergy analysis, economics, and environmental impact. The study revealed that the improved systems were more energy-efficient and environmentally friendly than before. The HH system recovered more low-temperature waste heat than the FHH system by 16.15–25.75 MW, and provided a shorter payback period of 2.37 years. The addition of FC and HE to WFGD improved exergy efficiency by 40 %. Both the FHH and HH systems achieved notable coal savings, with improvements ranging from 36 % to 37 % and 45–49 %, respectively, over the original system. Water of 14.18–38.9 t·h−1 and 362 t·h−1 were recovered through HE and FH, respectively. Overall, the improved systems provide guidance for the effective utilization of low temperature waste heat and in power plants.
{"title":"Simulation study on seasonal recovery of waste heat and water resources in flue gas and slurry after WFGD","authors":"Gaofeng Fan , Xinyue Gao , Chang’an Wang , Yujie Hou , Jinming Zhang , Jie Xu , Defu Che","doi":"10.1016/j.psep.2024.12.009","DOIUrl":"10.1016/j.psep.2024.12.009","url":null,"abstract":"<div><div>Efficient utilization of low-grade waste heat is pivotal for advancing energy savings and emissions reduction in power stations. However, the heat and water contained in flue gas and slurry post wet flue gas desulfurization (WFGD) have traditionally been underutilized. The flash-heat pump-heat exchanger (FHH) system and heat exchanger-heat pump (HH) system were proposed, employing heat exchangers (HE), flash column (FC), and absorption heat pumps (AHP) to utilize waste heat for seasonal heating and air heating purposes. A comprehensive evaluation of the systems was conducted, encompassing thermal performance, exergy analysis, economics, and environmental impact. The study revealed that the improved systems were more energy-efficient and environmentally friendly than before. The HH system recovered more low-temperature waste heat than the FHH system by 16.15–25.75 MW, and provided a shorter payback period of 2.37 years. The addition of FC and HE to WFGD improved exergy efficiency by 40 %. Both the FHH and HH systems achieved notable coal savings, with improvements ranging from 36 % to 37 % and 45–49 %, respectively, over the original system. Water of 14.18–38.9 t·h<sup>−1</sup> and 362 t·h<sup>−1</sup> were recovered through HE and FH, respectively. Overall, the improved systems provide guidance for the effective utilization of low temperature waste heat and in power plants.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"194 ","pages":"Pages 189-202"},"PeriodicalIF":6.9,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142821117","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-01DOI: 10.1016/j.psep.2024.12.047
Xiaoqi Ban , Jin Yao , Wanzhong Yin , Yu Xie , Taozhong Zhang , Weifan Du , Yulian Wang
The flotation separation of magnesite and dolomite poses significant challenges due to their highly similar crystal structures and surface physicochemical properties. To address the challenge of green and efficient decalcification and purification of low-grade magnesite resources, this study employed sesbania gum (SG) as an inhibitor in a flotation system with sodium oleate (NaOl) as the collector, achieving the flotation separation of magnesite from dolomite. Micro-flotation test results showed that in the NaOl system, SG exhibited a significant selective inhibitory effect on the flotation of dolomite, while it had almost no effect on the flotation of magnesite. At a pH of 10.0, the reagent scheme of 30 mg/L SG and 120 mg/L NaOl effectively achieved the flotation separation of the two minerals. This study elucidated the selective inhibition mechanism of SG on dolomite through zeta potential measurements, Fourier transform infrared spectroscopy (FTIR), surface wettability analysis, and X-ray photoelectron spectroscopy (XPS). The results of zeta potential measurements, FTIR spectroscopy, and surface wettability analysis indicated that SG exhibited very weak adsorption on the surface of magnesite, but strongly adsorbed onto the surface of dolomite, significantly hindering the adsorption of NaOl on dolomite. This resulted in a marked difference in the flotation behavior of the two minerals. XPS analysis revealed that the active hydroxyl groups in the polysaccharide structure of SG have a strong interaction with calcium sites, while exhibiting very low affinity for magnesium sites. Compared with traditional inhibitors, SG offers the advantages of being non-toxic, readily available, and biodegradable. The application of SG can substantially reduce environmental pollution in mineral processing, meeting global demands for greener practices in mineral beneficiation. Additionally, SG use enhances the sustainability and environmental compatibility of flotation production.
{"title":"Selective adsorption of eco-friendly inhibitor sesbania gum on dolomite for efficient flotation separation of magnesite and dolomite","authors":"Xiaoqi Ban , Jin Yao , Wanzhong Yin , Yu Xie , Taozhong Zhang , Weifan Du , Yulian Wang","doi":"10.1016/j.psep.2024.12.047","DOIUrl":"10.1016/j.psep.2024.12.047","url":null,"abstract":"<div><div>The flotation separation of magnesite and dolomite poses significant challenges due to their highly similar crystal structures and surface physicochemical properties. To address the challenge of green and efficient decalcification and purification of low-grade magnesite resources, this study employed sesbania gum (SG) as an inhibitor in a flotation system with sodium oleate (NaOl) as the collector, achieving the flotation separation of magnesite from dolomite. Micro-flotation test results showed that in the NaOl system, SG exhibited a significant selective inhibitory effect on the flotation of dolomite, while it had almost no effect on the flotation of magnesite. At a pH of 10.0, the reagent scheme of 30 mg/L SG and 120 mg/L NaOl effectively achieved the flotation separation of the two minerals. This study elucidated the selective inhibition mechanism of SG on dolomite through zeta potential measurements, Fourier transform infrared spectroscopy (FTIR), surface wettability analysis, and X-ray photoelectron spectroscopy (XPS). The results of zeta potential measurements, FTIR spectroscopy, and surface wettability analysis indicated that SG exhibited very weak adsorption on the surface of magnesite, but strongly adsorbed onto the surface of dolomite, significantly hindering the adsorption of NaOl on dolomite. This resulted in a marked difference in the flotation behavior of the two minerals. XPS analysis revealed that the active hydroxyl groups in the polysaccharide structure of SG have a strong interaction with calcium sites, while exhibiting very low affinity for magnesium sites. Compared with traditional inhibitors, SG offers the advantages of being non-toxic, readily available, and biodegradable. The application of SG can substantially reduce environmental pollution in mineral processing, meeting global demands for greener practices in mineral beneficiation. Additionally, SG use enhances the sustainability and environmental compatibility of flotation production.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"194 ","pages":"Pages 630-640"},"PeriodicalIF":6.9,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142867697","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-01DOI: 10.1016/j.psep.2024.12.044
Kun Lin, Zijian Su, Jiamei Xu, Tao Jiang, Yuanbo Zhang
The presence of toxic components (AlN and salts) was the major reason why secondary aluminum dross (SAD) was hard to utilize effectively. Hydrometallurgy can effectively realize the removal of AlN and salts, but it will produce large amounts of acid or alkali wastewater. In this study, a new idea of waste liquid recirculation-driven hydrolysis of SAD in the hydrometallurgical processes without acids or alkalis added was proposed to enhance deep denitrification. The results showed that AlN was readily hydrolyzed to Al(OH)3 and released NH3. The encapsulation of Al(OH)3 inhibited the deep removal of AlN. Fortunately, ammonia dissociated to OH-, making the disruption of the core-shell structure possible. Through leaching solution recirculation, ammonia was significantly enriched in the solution, which increased the pH and intensified the dissolution of Al(OH)3, thereby enhancing the denitrification of SAD. In addition, salts were also accumulated, which facilitated the subsequent recovery and promoted the dissociation of ammonia, thus further increasing the pH. The denitrification was increased from 70.56 % to 87.62 % with a residual nitrogen content of 0.71 % after 10 times of leaching solution recirculation. The leaching residue was a valuable aluminiferous raw material with an Al content of 40.23 %.
{"title":"Waste liquid recirculation-driven hydrolysis mechanism of secondary aluminum dross (SAD) in the hydrometallurgical processes","authors":"Kun Lin, Zijian Su, Jiamei Xu, Tao Jiang, Yuanbo Zhang","doi":"10.1016/j.psep.2024.12.044","DOIUrl":"10.1016/j.psep.2024.12.044","url":null,"abstract":"<div><div>The presence of toxic components (AlN and salts) was the major reason why secondary aluminum dross (SAD) was hard to utilize effectively. Hydrometallurgy can effectively realize the removal of AlN and salts, but it will produce large amounts of acid or alkali wastewater. In this study, a new idea of waste liquid recirculation-driven hydrolysis of SAD in the hydrometallurgical processes without acids or alkalis added was proposed to enhance deep denitrification. The results showed that AlN was readily hydrolyzed to Al(OH)<sub>3</sub> and released NH<sub>3</sub>. The encapsulation of Al(OH)<sub>3</sub> inhibited the deep removal of AlN. Fortunately, ammonia dissociated to OH<sup>-</sup>, making the disruption of the core-shell structure possible. Through leaching solution recirculation, ammonia was significantly enriched in the solution, which increased the pH and intensified the dissolution of Al(OH)<sub>3</sub>, thereby enhancing the denitrification of SAD. In addition, salts were also accumulated, which facilitated the subsequent recovery and promoted the dissociation of ammonia, thus further increasing the pH. The denitrification was increased from 70.56 % to 87.62 % with a residual nitrogen content of 0.71 % after 10 times of leaching solution recirculation. The leaching residue was a valuable aluminiferous raw material with an Al content of 40.23 %.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"194 ","pages":"Pages 593-603"},"PeriodicalIF":6.9,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142867701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-01DOI: 10.1016/j.psep.2024.12.042
Rehab M. Ali , Eslam Salama , Hesham A. Hamad
This research focuses on the microwave synthesis of the composite based on Ca/Si/Al oxides as a catalyst for effective and sustainable biodiesel production from waste frying oil (WFO) using an ultrasonic transesterification reaction. The novel catalyst Ca(OH)2-CaCO3/kaolin (CSAO), was synthesized by impregnation of kaolin with Ca(OH)2-CaCO3 to avoid the drawbacks of the sole Ca-based oxides usage and benefiting from the basic and acidic sites of Ca(OH)2-CaCO3 and kaolin, respectively. The catalysts have been characterized using XRD, FT-IR, Raman spectroscopy, SEM, TEM, and XPS. Then they utilized in the transesterification of WFO to evaluate and compare their performance in biodiesel production. A multi-variable catalytic transesterification process was performed using the response surface methodology (RSM). The experimental data were analyzed using analysis of variance (ANOVA). The highest biodiesel yield (98.7 %) was achieved using 1.5 % wt. CSAO catalyst/ wt. WFO, 6:1 methanol to oil (M/O) molar ratio, and 4 min reaction time using ultrasonic irradiation with an amplitude of 15 %. This outstanding performance is attributed to the acidic and basic sites of the CSAO. The CSAO catalyst demonstrated great stability against four successive cycles with high biodiesel production efficiency. The petrodiesel physicochemical properties have been significantly improved after blending with the produced biodiesel such as; density, viscosity, calorific value, cetane index, cloud point, pour point, and flash point. Moreover, exhaust gas emissions have been strongly reduced like hydrocarbon (HC), carbon monoxide (CO), and sulfur oxides (SOx). This work is based on “wastes treat wastes” and provides a promising catalyst from Ca-based wastes without the Ca2 + leaching and saponification process.
{"title":"A novel technology for microwave-assisted synthesis of new Ca/Si/Al composite oxide-based catalyst for boosting the ultrasound-assisted biodiesel production","authors":"Rehab M. Ali , Eslam Salama , Hesham A. Hamad","doi":"10.1016/j.psep.2024.12.042","DOIUrl":"10.1016/j.psep.2024.12.042","url":null,"abstract":"<div><div>This research focuses on the microwave synthesis of the composite based on Ca/Si/Al oxides as a catalyst for effective and sustainable biodiesel production from waste frying oil (WFO) using an ultrasonic transesterification reaction. The novel catalyst Ca(OH)<sub>2</sub>-CaCO<sub>3</sub>/kaolin (CSAO), was synthesized by impregnation of kaolin with Ca(OH)<sub>2</sub>-CaCO<sub>3</sub> to avoid the drawbacks of the sole Ca-based oxides usage and benefiting from the basic and acidic sites of Ca(OH)<sub>2</sub>-CaCO<sub>3</sub> and kaolin, respectively. The catalysts have been characterized using XRD, FT-IR, Raman spectroscopy, SEM, TEM, and XPS. Then they utilized in the transesterification of WFO to evaluate and compare their performance in biodiesel production. A multi-variable catalytic transesterification process was performed using the response surface methodology (RSM). The experimental data were analyzed using analysis of variance (ANOVA). The highest biodiesel yield (98.7 %) was achieved using 1.5 % wt. CSAO catalyst/ wt. WFO, 6:1 methanol to oil (M/O) molar ratio, and 4 min reaction time using ultrasonic irradiation with an amplitude of 15 %. This outstanding performance is attributed to the acidic and basic sites of the CSAO. The CSAO catalyst demonstrated great stability against four successive cycles with high biodiesel production efficiency. The petrodiesel physicochemical properties have been significantly improved after blending with the produced biodiesel such as; density, viscosity, calorific value, cetane index, cloud point, pour point, and flash point. Moreover, exhaust gas emissions have been strongly reduced like hydrocarbon (HC), carbon monoxide (CO), and sulfur oxides (SO<sub>x</sub>). This work is based on “wastes treat wastes” and provides a promising catalyst from Ca-based wastes without the Ca<sup>2 +</sup> leaching and saponification process.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"194 ","pages":"Pages 674-687"},"PeriodicalIF":6.9,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142867702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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