Xi Zhang, Haoyuan Zheng, Hong Xu, Jie Huang, Qianyuan Mo, Guishang Sheng
N-S co-doped magnetic biochar (NSMBC) was synthesized by a two-step pyrolysis technique and used for the degradation of tetracycline (TC) by activated persulfate (peroxomonosulfate [PMS]). Batch experiments showed that the pyrolysis temperature and doping ratio affected the catalytic performance of NSMBC. The degradation rate of TC in the NSMBC/PMS system prepared at 350°C with a doping ratio of 33% was up to 94.50%, and the system exhibited strong pH adaptability and resistance to environmental interference. The results of free radical burst and electron paramagnetic resonance (EPR) spectroscopy experiments indicated the free radical pathway (SO4•−) for TC degradation. In addition, NSMBC has good stability and excellent magnetic properties favorable for separation and recovery. This study not only provides a new idea for the synthesis of efficient and stable catalysts but also provides a green pathway for the resourceization of pomelo peel waste.
{"title":"Efficient activation of N and S co-doped magnetic biochar for peroxomonosulfate degradation of tetracycline","authors":"Xi Zhang, Haoyuan Zheng, Hong Xu, Jie Huang, Qianyuan Mo, Guishang Sheng","doi":"10.1002/apj.3156","DOIUrl":"https://doi.org/10.1002/apj.3156","url":null,"abstract":"N-S co-doped magnetic biochar (NSMBC) was synthesized by a two-step pyrolysis technique and used for the degradation of tetracycline (TC) by activated persulfate (peroxomonosulfate [PMS]). Batch experiments showed that the pyrolysis temperature and doping ratio affected the catalytic performance of NSMBC. The degradation rate of TC in the NSMBC/PMS system prepared at 350°C with a doping ratio of 33% was up to 94.50%, and the system exhibited strong pH adaptability and resistance to environmental interference. The results of free radical burst and electron paramagnetic resonance (EPR) spectroscopy experiments indicated the free radical pathway (SO<sub>4</sub><sup>•−</sup>) for TC degradation. In addition, NSMBC has good stability and excellent magnetic properties favorable for separation and recovery. This study not only provides a new idea for the synthesis of efficient and stable catalysts but also provides a green pathway for the resourceization of pomelo peel waste.","PeriodicalId":8852,"journal":{"name":"Asia-Pacific Journal of Chemical Engineering","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142253092","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This review focused on the potential applications of sulfonated carbon–based heterogeneous acid catalysts for the hydrolysis of lignocellulosic biomass (LCB) fuel feedstock and the development of membrane electrode assembly (MEA) for the direct biomass redox flow fuel cell (DBRFFC). LCBs are hydrolysed to yield simple sugars, which are subsequently oxidized over catalysts in the anode tank of the DBRFFC to generate electricity. Ferric chloride used as a catalyst in the DBRFFC is not efficient for glucose production from LCB, such that the power performance of the DBRFFC is affected during glucose oxidation due to low glucose yield from LCB for electron generation. Sulfonated carbon–based solid acid catalysts (SCSACs) have been established as efficient catalysts for the hydrolysis of LCB and as metal catalyst supports for the fabrication of MEA for further oxidation of glucose and its oxidation by‐products. These capabilities of SCSACs can be explored and applied to significantly improve the power output of the DBRFFC through efficient hybrid catalyst design. There is still a scarcity of literature on this subject and their combination with ferric chloride to enhance glucose yield and oxidation in DBRFFC. This gap was filled by discussing the various types of sulfonated carbon–based catalysts, highlighting their synthesis routes, and their applications in organic compound synthesis, and membrane electrode development in DBRFFC. The knowledge derived will certainly be beneficial to researchers willing to improve the performance of DBRFFC through molecular catalyst design and electrode membrane development for application in DBRFFC.
{"title":"Sulfonated carbon–based heterogeneous acid catalysts in direct biomass redox flow fuel cell: A review","authors":"Boniface Ifeanyi Ugwu, Christogonus Oduney Akalezi, Innocent Sunday Ike, Toochukwu Eqwutosi Ogbulie, Emeka Emmanuel Oguzie","doi":"10.1002/apj.3158","DOIUrl":"https://doi.org/10.1002/apj.3158","url":null,"abstract":"This review focused on the potential applications of sulfonated carbon–based heterogeneous acid catalysts for the hydrolysis of lignocellulosic biomass (LCB) fuel feedstock and the development of membrane electrode assembly (MEA) for the direct biomass redox flow fuel cell (DBRFFC). LCBs are hydrolysed to yield simple sugars, which are subsequently oxidized over catalysts in the anode tank of the DBRFFC to generate electricity. Ferric chloride used as a catalyst in the DBRFFC is not efficient for glucose production from LCB, such that the power performance of the DBRFFC is affected during glucose oxidation due to low glucose yield from LCB for electron generation. Sulfonated carbon–based solid acid catalysts (SCSACs) have been established as efficient catalysts for the hydrolysis of LCB and as metal catalyst supports for the fabrication of MEA for further oxidation of glucose and its oxidation by‐products. These capabilities of SCSACs can be explored and applied to significantly improve the power output of the DBRFFC through efficient hybrid catalyst design. There is still a scarcity of literature on this subject and their combination with ferric chloride to enhance glucose yield and oxidation in DBRFFC. This gap was filled by discussing the various types of sulfonated carbon–based catalysts, highlighting their synthesis routes, and their applications in organic compound synthesis, and membrane electrode development in DBRFFC. The knowledge derived will certainly be beneficial to researchers willing to improve the performance of DBRFFC through molecular catalyst design and electrode membrane development for application in DBRFFC.","PeriodicalId":8852,"journal":{"name":"Asia-Pacific Journal of Chemical Engineering","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142253093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nanozymes have significantly advanced sensing assays by replicating native enzyme functions. However, designing nanozymes with high catalytic activity and easy recyclability remains challenging. The study presented here has resulted in the development of a highly efficient and sensitive colorimetric system for the detection of uric acid, utilizing MnFe2O4@HNTs—a novel composite material consisting of MnFe2O4 loaded onto halloysite nanotubes. These nanocomposites exhibited outstanding peroxidase‐like activity and attractive magnetic properties. The catalytic efficiency of the MnFe2O4@HNTs in the oxidation of 3,3′,5,5′‐tetramethylbenzidine, in the presence of H2O2, was remarkable, leading to a distinct color change from colorless to blue. A linear relationship was observed between absorbance and UA concentration in the range of 1–20 μM, with a detection limit as low as 52 nM. Mechanistic investigations revealed that reactive oxygen species (ROS), specifically singlet oxygen (1O2), were generated through the decomposition of H2O2, which is responsible for the peroxidase‐like activity demonstrated by the MnFe2O4@HNTs. The method showed minimal interference from serum substances and high selectivity. Magnetic MnFe2O4 allowed easy separation and maintained over 95% activity after seven reuse cycles. The developed assay was successfully applied to the detection of uric acid in human serum, achieving recoveries greater than 98.60%. This research significantly advances the design of recyclable high‐performance nanozymes and establishes an effective colorimetric sensing platform for UA detection in clinical samples, potentially improving diagnostic tools for healthcare applications.
{"title":"Enhanced peroxidase‐like activity of MnFe2O4 nanoparticles on halloysite nanotubes for uric acid detection","authors":"Hengxia Shen, Zhenbo Xiang, Anfang Dang","doi":"10.1002/apj.3143","DOIUrl":"https://doi.org/10.1002/apj.3143","url":null,"abstract":"Nanozymes have significantly advanced sensing assays by replicating native enzyme functions. However, designing nanozymes with high catalytic activity and easy recyclability remains challenging. The study presented here has resulted in the development of a highly efficient and sensitive colorimetric system for the detection of uric acid, utilizing MnFe<jats:sub>2</jats:sub>O<jats:sub>4</jats:sub>@HNTs—a novel composite material consisting of MnFe<jats:sub>2</jats:sub>O<jats:sub>4</jats:sub> loaded onto halloysite nanotubes. These nanocomposites exhibited outstanding peroxidase‐like activity and attractive magnetic properties. The catalytic efficiency of the MnFe<jats:sub>2</jats:sub>O<jats:sub>4</jats:sub>@HNTs in the oxidation of 3,3′,5,5′‐tetramethylbenzidine, in the presence of H<jats:sub>2</jats:sub>O<jats:sub>2</jats:sub>, was remarkable, leading to a distinct color change from colorless to blue. A linear relationship was observed between absorbance and UA concentration in the range of 1–20 μM, with a detection limit as low as 52 nM. Mechanistic investigations revealed that reactive oxygen species (ROS), specifically singlet oxygen (<jats:sup>1</jats:sup>O<jats:sub>2</jats:sub>), were generated through the decomposition of H<jats:sub>2</jats:sub>O<jats:sub>2</jats:sub>, which is responsible for the peroxidase‐like activity demonstrated by the MnFe<jats:sub>2</jats:sub>O<jats:sub>4</jats:sub>@HNTs. The method showed minimal interference from serum substances and high selectivity. Magnetic MnFe<jats:sub>2</jats:sub>O<jats:sub>4</jats:sub> allowed easy separation and maintained over 95% activity after seven reuse cycles. The developed assay was successfully applied to the detection of uric acid in human serum, achieving recoveries greater than 98.60%. This research significantly advances the design of recyclable high‐performance nanozymes and establishes an effective colorimetric sensing platform for UA detection in clinical samples, potentially improving diagnostic tools for healthcare applications.","PeriodicalId":8852,"journal":{"name":"Asia-Pacific Journal of Chemical Engineering","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142220322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Muhd Izzudin Fikry Zainuddin, Abdul Latif Ahmad, Meor Muhammad Hafiz Shah Buddin, Mohamad Alif Adnan
Hollow fibre membrane (HFM) is favourable for carbon dioxide (CO2) due to its high packing density and high volume to area ratio. In this study, the effect of air gap and bore fluid ratio is explored to study its influence on the morphology and separation performance. With high dope extrusion rate (DER), the shear‐induced polymer orientation can be preserved with low air gap which come with the cost of deformed lumen. As such, the coagulant activity of the bore fluid can be reduced by introducing solvent, which in turn reduces rate of phase inversion to prevent sudden contraction of polymer at low air gap, thus allowing proper formation of lumen. With the presence of solvent, the flowability of the dope solution increased due to reduced viscosity as the bore fluid with high solvent content make contact the external coagulant. HFM spun with low air gap with the presence of solvent in the bore fluid shows increased stretched ratio due to the influence of gravitational pull upon being extruded from the spinneret. This in turn improved the polymer chain orientation due to the stretch across the spinning line. Subsequently, HFM spun with 80 wt.% of N‐methyl‐2‐pyrollidone (NMP) in the bore fluid using narrow gap spinneret with 5‐cm air gap shows the highest ideal CO2/N2 and CO2/CH4 selectivity at 23.4 and 28 respectively, even though it also exhibit the lowest CO2 permeance at only 3.1 GPU which was ascribed to the formation of dense skin layer. Meanwhile, when HFM was spun with a bigger annulus gap, the ideal CO2/N2 and CO2/CH4 selectivity slightly dropped, however the CO2 permeance exhibit increment.
{"title":"CO2 capture for environmental remediation with hollow fibre membrane: Impact of air gap and bore fluid ratio onto the morphology and performance","authors":"Muhd Izzudin Fikry Zainuddin, Abdul Latif Ahmad, Meor Muhammad Hafiz Shah Buddin, Mohamad Alif Adnan","doi":"10.1002/apj.3157","DOIUrl":"https://doi.org/10.1002/apj.3157","url":null,"abstract":"Hollow fibre membrane (HFM) is favourable for carbon dioxide (CO<jats:sub>2</jats:sub>) due to its high packing density and high volume to area ratio. In this study, the effect of air gap and bore fluid ratio is explored to study its influence on the morphology and separation performance. With high dope extrusion rate (DER), the shear‐induced polymer orientation can be preserved with low air gap which come with the cost of deformed lumen. As such, the coagulant activity of the bore fluid can be reduced by introducing solvent, which in turn reduces rate of phase inversion to prevent sudden contraction of polymer at low air gap, thus allowing proper formation of lumen. With the presence of solvent, the flowability of the dope solution increased due to reduced viscosity as the bore fluid with high solvent content make contact the external coagulant. HFM spun with low air gap with the presence of solvent in the bore fluid shows increased stretched ratio due to the influence of gravitational pull upon being extruded from the spinneret. This in turn improved the polymer chain orientation due to the stretch across the spinning line. Subsequently, HFM spun with 80 wt.% of N‐methyl‐2‐pyrollidone (NMP) in the bore fluid using narrow gap spinneret with 5‐cm air gap shows the highest ideal CO<jats:sub>2</jats:sub>/N<jats:sub>2</jats:sub> and CO<jats:sub>2</jats:sub>/CH<jats:sub>4</jats:sub> selectivity at 23.4 and 28 respectively, even though it also exhibit the lowest CO<jats:sub>2</jats:sub> permeance at only 3.1 GPU which was ascribed to the formation of dense skin layer. Meanwhile, when HFM was spun with a bigger annulus gap, the ideal CO<jats:sub>2</jats:sub>/N<jats:sub>2</jats:sub> and CO<jats:sub>2</jats:sub>/CH<jats:sub>4</jats:sub> selectivity slightly dropped, however the CO<jats:sub>2</jats:sub> permeance exhibit increment.","PeriodicalId":8852,"journal":{"name":"Asia-Pacific Journal of Chemical Engineering","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142220334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The jet impingement–negative‐pressure reactor (JI‐NPR) is a continuous and efficient technology designed to remove ammonia without clogging. Prior research has discovered that the changing movement of a porous jet impinging under negative‐pressure conditions is distinguished by a more pronounced distribution over many regions. This study utilizes the CFD numerical simulation method in conjunction with the MATLAB platform to investigate the fractal characteristics of water phase distribution, velocity, turbulence intensity, vortex amount, and other parameters at various locations. The fractal dimension is employed as a criterion to analyze the chaotic characteristics of this multi‐area distribution phenomenon. The study demonstrates that the effectiveness of deamination removal can be enhanced by quantitatively assessing the complex characteristics in the fluid flow using the chaotic fractal theory, which facilitates the identification of the ideal parameter settings. The optimal deamination effect can be achieved in the reactor when the jet velocity is set to 3.45 m/s and the negative pressure is maintained at 20 400 Pa.
{"title":"An insight into the investigation of partition characteristics of flow fields based on chaos fractal theory in a jet impingement–negative‐pressure reactor","authors":"Yuxi Hu, Yingying Dong, Guangchao Jiang, Zonghan Li, Fachen Qiu","doi":"10.1002/apj.3155","DOIUrl":"https://doi.org/10.1002/apj.3155","url":null,"abstract":"The jet impingement–negative‐pressure reactor (JI‐NPR) is a continuous and efficient technology designed to remove ammonia without clogging. Prior research has discovered that the changing movement of a porous jet impinging under negative‐pressure conditions is distinguished by a more pronounced distribution over many regions. This study utilizes the CFD numerical simulation method in conjunction with the MATLAB platform to investigate the fractal characteristics of water phase distribution, velocity, turbulence intensity, vortex amount, and other parameters at various locations. The fractal dimension is employed as a criterion to analyze the chaotic characteristics of this multi‐area distribution phenomenon. The study demonstrates that the effectiveness of deamination removal can be enhanced by quantitatively assessing the complex characteristics in the fluid flow using the chaotic fractal theory, which facilitates the identification of the ideal parameter settings. The optimal deamination effect can be achieved in the reactor when the jet velocity is set to 3.45 m/s and the negative pressure is maintained at 20 400 Pa.","PeriodicalId":8852,"journal":{"name":"Asia-Pacific Journal of Chemical Engineering","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142220335","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Arian Samiei, Homayun Khezraqa, Habib Etemadi, Elham Shokri
In recent years, there has been growing interest in using polymer nanocomposite membranes as a more advanced method for removing pollutants from water and treating wastewater for various purposes. In this study, thin‐film nanocomposite (TFN) membranes of polycarbonate/polyvinyl alcohol–titanium dioxide thin‐film (PC/PVA–TiO2) were fabricated by dip‐coating a PC substrate in a PVA/TiO2 solution. Various methods, including attenuated total reflectance‐Fourier transform infrared (ATR‐FTIR) spectroscopy, field emission scanning electron microscopy (FE‐SEM), atomic force microscopy (AFM), and water contact angle were utilized to assess the structural characteristics of the produced membranes. The PC/PVA thin‐film composite (TFC) and PC/PVA–TiO2 TFN membranes were then examined in a submerged membrane system to evaluate their effectiveness in filtering humic acid (HA) under various vacuum transmembrane pressure (0.3 and 0.6 bar) condition. The FTIR‐ATR results confirmed the formation of the active layer of PVA/TiO2 nanoparticles (NPs). It was observed that adding 1 wt.% of TiO2 NPs to the active layer of PVA/TiO2 significantly enhanced the water contact angle from 77.5° for PC support to 55.3° for PC/PVA–TiO2 (0.1) TFN membranes. Furthermore, the FE‐SEM results confirmed the formation of an active layer of PVA/TiO2 with a thickness of 237.87 nm. The pure water flux increased from 101.64 L/m2h for the PC/PVA TFC membrane to 144.02 L/m2h and 199.09 L/m2h for the PC/PVA–TiO2 (0.05) and PC/PVA–TiO2 (0.1) TFN membranes, respectively. Also, the results revealed that at lower transmembrane pressure, all membranes showed higher value in HA removal as compared to when higher transmembrane pressure was used.
{"title":"Fabrication and performance evaluation of polycarbonate/polyvinyl alcohol–titanium dioxide thin‐film nanocomposite membranes for water treatment","authors":"Arian Samiei, Homayun Khezraqa, Habib Etemadi, Elham Shokri","doi":"10.1002/apj.3150","DOIUrl":"https://doi.org/10.1002/apj.3150","url":null,"abstract":"In recent years, there has been growing interest in using polymer nanocomposite membranes as a more advanced method for removing pollutants from water and treating wastewater for various purposes. In this study, thin‐film nanocomposite (TFN) membranes of polycarbonate/polyvinyl alcohol–titanium dioxide thin‐film (PC/PVA–TiO<jats:sub>2</jats:sub>) were fabricated by dip‐coating a PC substrate in a PVA/TiO<jats:sub>2</jats:sub> solution. Various methods, including attenuated total reflectance‐Fourier transform infrared (ATR‐FTIR) spectroscopy, field emission scanning electron microscopy (FE‐SEM), atomic force microscopy (AFM), and water contact angle were utilized to assess the structural characteristics of the produced membranes. The PC/PVA thin‐film composite (TFC) and PC/PVA–TiO<jats:sub>2</jats:sub> TFN membranes were then examined in a submerged membrane system to evaluate their effectiveness in filtering humic acid (HA) under various vacuum transmembrane pressure (0.3 and 0.6 bar) condition. The FTIR‐ATR results confirmed the formation of the active layer of PVA/TiO<jats:sub>2</jats:sub> nanoparticles (NPs). It was observed that adding 1 wt.% of TiO<jats:sub>2</jats:sub> NPs to the active layer of PVA/TiO<jats:sub>2</jats:sub> significantly enhanced the water contact angle from 77.5° for PC support to 55.3° for PC/PVA–TiO<jats:sub>2</jats:sub> (0.1) TFN membranes. Furthermore, the FE‐SEM results confirmed the formation of an active layer of PVA/TiO<jats:sub>2</jats:sub> with a thickness of 237.87 nm. The pure water flux increased from 101.64 L/m<jats:sup>2</jats:sup>h for the PC/PVA TFC membrane to 144.02 L/m<jats:sup>2</jats:sup>h and 199.09 L/m<jats:sup>2</jats:sup>h for the PC/PVA–TiO<jats:sub>2</jats:sub> (0.05) and PC/PVA–TiO<jats:sub>2</jats:sub> (0.1) TFN membranes, respectively. Also, the results revealed that at lower transmembrane pressure, all membranes showed higher value in HA removal as compared to when higher transmembrane pressure was used.","PeriodicalId":8852,"journal":{"name":"Asia-Pacific Journal of Chemical Engineering","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142227374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Bhumarapu Venkateswarlu, Sang Woo Joo, Nallagundla Nagendra, Ahmed Sayed M Metwally
The idea of a hybrid nanofluid (HNF) has sparked curiosity among many scientists because of its ability to enhance thermal characteristics, leading to elevated rates of heat transfer (HT). These HNFs are utilized in various engineering and industrial settings, such as electronics cooling, manufacturing, naval structures, biomedical applications, and drug delivery. The current study investigates the analysis of irreversibility in EMHD [Cu + TiO2/H2O]h flow over a stretching sheet with radiation and viscous dissipation. The governing PDEs are converted into ODEs using similarity variables. These ODEs are then solved using the RKF method along with a shooting technique. The effects of different physical parameters on the velocity and temperature distributions of the HNF, as well as on HT and surface drag force, are thoroughly examined and presented in graphs. The velocity of [TiO2/water]n flow declines as the magnetic field strength rises, but it rises with greater electric field values for [Cu + TiO2/water]h. The temperature of the [Cu + TiO2/water]h increases with elevated levels of radiation, Eckert number, and heat generation strength. Higher Reynolds and Brinkman numbers result in a rise in entropy generation for [Cu + TiO2/H2O]h, whereas the Bejan number decreases to the same extent. The HT rate in [Cu + TiO2/H2O]h increases by 3.05% as the Eckert number rises, while it drops by 4.01% when there is significant thermal radiation. Skin friction reduces by 3.21% in [TiO2/water]n as the electric field strength increases, whereas it decreases by 4.05% with an increase in magnetic field strength. These discoveries offer valuable perspectives on furthering the utilization of HNFs in engineering and industrial operations.
{"title":"Numerical investigation of electromagnetic [Cu + TiO2/H2O]h hybrid nanofluid flow with solar radiation over an exponential stretching surface","authors":"Bhumarapu Venkateswarlu, Sang Woo Joo, Nallagundla Nagendra, Ahmed Sayed M Metwally","doi":"10.1002/apj.3154","DOIUrl":"https://doi.org/10.1002/apj.3154","url":null,"abstract":"The idea of a hybrid nanofluid (HNF) has sparked curiosity among many scientists because of its ability to enhance thermal characteristics, leading to elevated rates of heat transfer (HT). These HNFs are utilized in various engineering and industrial settings, such as electronics cooling, manufacturing, naval structures, biomedical applications, and drug delivery. The current study investigates the analysis of irreversibility in EMHD [Cu + TiO<jats:sub>2</jats:sub>/H<jats:sub>2</jats:sub>O]<jats:sup>h</jats:sup> flow over a stretching sheet with radiation and viscous dissipation. The governing PDEs are converted into ODEs using similarity variables. These ODEs are then solved using the RKF method along with a shooting technique. The effects of different physical parameters on the velocity and temperature distributions of the HNF, as well as on HT and surface drag force, are thoroughly examined and presented in graphs. The velocity of [TiO<jats:sub>2</jats:sub>/water]<jats:sup>n</jats:sup> flow declines as the magnetic field strength rises, but it rises with greater electric field values for [Cu + TiO<jats:sub>2</jats:sub>/water]<jats:sup>h</jats:sup>. The temperature of the [Cu + TiO<jats:sub>2</jats:sub>/water]<jats:sup>h</jats:sup> increases with elevated levels of radiation, Eckert number, and heat generation strength. Higher Reynolds and Brinkman numbers result in a rise in entropy generation for [Cu + TiO<jats:sub>2</jats:sub>/H<jats:sub>2</jats:sub>O]<jats:sup>h</jats:sup>, whereas the Bejan number decreases to the same extent. The HT rate in [Cu + TiO<jats:sub>2</jats:sub>/H<jats:sub>2</jats:sub>O]<jats:sup>h</jats:sup> increases by 3.05% as the Eckert number rises, while it drops by 4.01% when there is significant thermal radiation. Skin friction reduces by 3.21% in [TiO<jats:sub>2</jats:sub>/water]<jats:sup>n</jats:sup> as the electric field strength increases, whereas it decreases by 4.05% with an increase in magnetic field strength. These discoveries offer valuable perspectives on furthering the utilization of HNFs in engineering and industrial operations.","PeriodicalId":8852,"journal":{"name":"Asia-Pacific Journal of Chemical Engineering","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142220338","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The synthesis of high‐efficiency magnetic composite photocatalyst by doping magnetic cobalt ferrite and compounding single semiconductor photocatalyst is a promising strategy to improve the oxidation ability of photocatalytic systems. In this paper, CoFe1.95Dy0.05O4 (CFDO) was prepared by doping Dy element into magnetic CoFe2O4, and Ag2S (AS)/CFDO with high‐efficiency magnetic photocatalyst was synthesized by compounding AS with CFDO as the substrate. The photocatalytic samples were characterized by different advanced characterization methods, and their photocatalytic degradation of methylene blue (MB) was studied. The results show that AS/CFDO exhibits higher visible light response, excellent photogenerated charge separation ability and migration efficiency, and excellent catalytic performance in the catalytic degradation system. The photocatalytic activity of AS/CFDO was the highest, and its photocatalytic degradation kinetic constant K was 2.48 and 1.54 times that of AS and CFDO, respectively. In addition, the catalyst contained in the catalytically contaminated solution can be effectively separated by an external magnetic field to achieve multiple cycles of degradation and recycling. The cyclic degradation experiments showed that AS/CFDO exhibited high degradation stability during the photodegradation process. After the fifth reuse, the degradation efficiency was still more than 88.0%. Finally, the possible photocatalytic mechanism of the samples was discussed. Therefore, this work provides an effective solution for the construction of photocatalysts with high efficiency, magnetic recovery, and cyclic degradation stability and avoids the secondary pollution of catalysts to organic wastewater. It is of great significance to create an environmentally friendly catalytic method for efficient cyclic degradation of organic wastewater.
通过掺杂磁性钴铁氧体和复合单一半导体光催化剂来合成高效磁性复合光催化剂，是提高光催化体系氧化能力的一种很有前途的策略。本文通过在磁性 CoFe2O4 中掺杂镝元素制备了 CoFe1.95Dy0.05O4（CFDO），并以 CFDO 为基底与 AS 复合合成了 Ag2S（AS）/CFDO 高效磁性光催化剂。采用不同的先进表征方法对光催化样品进行了表征，并研究了它们对亚甲基蓝（MB）的光催化降解作用。结果表明，AS/CFDO 在催化降解体系中表现出更高的可见光响应、优异的光生电荷分离能力和迁移效率以及优良的催化性能。AS/CFDO 的光催化活性最高，其光催化降解动力学常数 K 分别是 AS 和 CFDO 的 2.48 倍和 1.54 倍。此外，催化污染溶液中所含的催化剂可通过外加磁场有效分离，实现多次循环降解和回收利用。循环降解实验表明，AS/CFDO 在光降解过程中表现出较高的降解稳定性。第五次重复使用后，降解效率仍超过 88.0%。最后，讨论了样品可能的光催化机理。因此，这项工作为构建具有高效率、磁性恢复和循环降解稳定性的光催化剂提供了有效的解决方案，并避免了催化剂对有机废水的二次污染。这对于创造一种高效循环降解有机废水的环境友好型催化方法具有重要意义。
{"title":"Preparation and photocatalytic mechanism of magnetic Ag2S/CoFe1.95Dy0.05O4 Z‐scheme heterojunction","authors":"Liu Qingwang, Xu Mai, Meng Ying","doi":"10.1002/apj.3153","DOIUrl":"https://doi.org/10.1002/apj.3153","url":null,"abstract":"The synthesis of high‐efficiency magnetic composite photocatalyst by doping magnetic cobalt ferrite and compounding single semiconductor photocatalyst is a promising strategy to improve the oxidation ability of photocatalytic systems. In this paper, CoFe<jats:sub>1.95</jats:sub>Dy<jats:sub>0.05</jats:sub>O<jats:sub>4</jats:sub> (CFDO) was prepared by doping Dy element into magnetic CoFe<jats:sub>2</jats:sub>O<jats:sub>4</jats:sub>, and Ag<jats:sub>2</jats:sub>S (AS)/CFDO with high‐efficiency magnetic photocatalyst was synthesized by compounding AS with CFDO as the substrate. The photocatalytic samples were characterized by different advanced characterization methods, and their photocatalytic degradation of methylene blue (MB) was studied. The results show that AS/CFDO exhibits higher visible light response, excellent photogenerated charge separation ability and migration efficiency, and excellent catalytic performance in the catalytic degradation system. The photocatalytic activity of AS/CFDO was the highest, and its photocatalytic degradation kinetic constant K was 2.48 and 1.54 times that of AS and CFDO, respectively. In addition, the catalyst contained in the catalytically contaminated solution can be effectively separated by an external magnetic field to achieve multiple cycles of degradation and recycling. The cyclic degradation experiments showed that AS/CFDO exhibited high degradation stability during the photodegradation process. After the fifth reuse, the degradation efficiency was still more than 88.0%. Finally, the possible photocatalytic mechanism of the samples was discussed. Therefore, this work provides an effective solution for the construction of photocatalysts with high efficiency, magnetic recovery, and cyclic degradation stability and avoids the secondary pollution of catalysts to organic wastewater. It is of great significance to create an environmentally friendly catalytic method for efficient cyclic degradation of organic wastewater.","PeriodicalId":8852,"journal":{"name":"Asia-Pacific Journal of Chemical Engineering","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142220339","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
MoV‐based composites stand out as the most promising potential catalysts targeted for direct production of acrylic acid from alkane/alkene substances. Herein, MoVTeNbO powder was synthesized and successfully fabricated by adding graphite as an appropriate tableting agent. Without employing graphite as lubricant, the fabrication of tablets was not practicable. The physicochemical effects of graphite on the catalyst properties were investigated via characterization by X‐ray diffraction (XRD), Brunauer–Emmett–Teller (BET), scanning electron microscopy (SEM), ammonia temperature‐programmed desorption (NH3‐TPD), and thermal gravimetric analysis (TGA) methods. In addition to the easy and operative formation of tablets by consisting graphite, TGA results indicated better thermal stability compared to the bare powder. No harmful impact of graphite on the catalyst crystalline phases and morphology was detected by XRD and SEM analysis. The SEM images proved the graphite incorporation as a binder in the physical combination of the catalyst particles along the compression process, resulting in the desired physical resistance. Graphite caused a slight decrease in the BET surface area and final catalyst acidity. Despite the effect of reducing propene conversion, interestingly, a substantial improvement in the yield of acrylic acid was found by tableting. The graphite as an inert agent suppressed hot spots on the catalyst surface, leading to superior consistency in activity over time as well as lower selectivity to undesirable COx.
MoV 基复合材料是最有前途的潜在催化剂，可用于从烷烃/烯烃物质直接生产丙烯酸。本文合成了 MoVTeNbO 粉末，并通过添加石墨作为适当的压片剂成功制成。如果不使用石墨作为润滑剂，则无法制作片剂。通过 X 射线衍射 (XRD)、Brunauer-Emmett-Teller (BET)、扫描电子显微镜 (SEM)、氨温程控解吸 (NH3-TPD) 和热重分析 (TGA) 等方法研究了石墨对催化剂性能的物理化学影响。与裸粉末相比，TGA 结果表明，石墨不仅易于形成片剂，而且操作简便。通过 XRD 和 SEM 分析，没有发现石墨对催化剂晶相和形态造成有害影响。扫描电子显微镜图像证明，在压缩过程中，石墨是催化剂颗粒物理结合的粘合剂，从而产生了理想的物理阻力。石墨导致 BET 表面积和最终催化剂酸度略有下降。尽管会降低丙烯的转化率，但有趣的是，通过压片，丙烯酸的产率得到了大幅提高。石墨作为一种惰性剂，抑制了催化剂表面的热点，从而使催化剂的活性长期保持优异的一致性，并降低了对不良 COx 的选择性。
{"title":"Physicochemical influence of graphite agent for fabrication of MoVTeNbO catalyst for direct oxidation of propene to acrylic acid","authors":"Hossein Khosravi Rouzbahani, Azam Akbari, Golshan Mazloom","doi":"10.1002/apj.3149","DOIUrl":"https://doi.org/10.1002/apj.3149","url":null,"abstract":"MoV‐based composites stand out as the most promising potential catalysts targeted for direct production of acrylic acid from alkane/alkene substances. Herein, MoVTeNbO powder was synthesized and successfully fabricated by adding graphite as an appropriate tableting agent. Without employing graphite as lubricant, the fabrication of tablets was not practicable. The physicochemical effects of graphite on the catalyst properties were investigated via characterization by X‐ray diffraction (XRD), Brunauer–Emmett–Teller (BET), scanning electron microscopy (SEM), ammonia temperature‐programmed desorption (NH<jats:sub>3</jats:sub>‐TPD), and thermal gravimetric analysis (TGA) methods. In addition to the easy and operative formation of tablets by consisting graphite, TGA results indicated better thermal stability compared to the bare powder. No harmful impact of graphite on the catalyst crystalline phases and morphology was detected by XRD and SEM analysis. The SEM images proved the graphite incorporation as a binder in the physical combination of the catalyst particles along the compression process, resulting in the desired physical resistance. Graphite caused a slight decrease in the BET surface area and final catalyst acidity. Despite the effect of reducing propene conversion, interestingly, a substantial improvement in the yield of acrylic acid was found by tableting. The graphite as an inert agent suppressed hot spots on the catalyst surface, leading to superior consistency in activity over time as well as lower selectivity to undesirable CO<jats:sub>x</jats:sub>.","PeriodicalId":8852,"journal":{"name":"Asia-Pacific Journal of Chemical Engineering","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142220361","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yuanhang Zhang, Yongbo Du, Jingkun Zhang, Defu Che
Self‐excited thermoacoustic instability (SETAI) is a dangerous phenomenon in combustion equipment. While it is widely acknowledged that SETAI behavior is determined by the couple between pressure and heat release oscillation, their phase difference is difficult to predict, which impedes the development of SETAI control technology. With the aim of passive control technology development, this paper conducted experiment on a premixed hedge combustor to explore the mechanism whereby premixed chamber length (LP) and equivalence ratio (φ) collaboratively influence SETAI behavior. Results showed LP mainly affects the pressure mode shape within premixed chamber and consequently alters the phase difference between pressure and flowrate oscillation at combustion chamber inlet. Changing φ gives rise to different reaction time‐lag (τ), thus altering the phase difference between flowrate and reaction heat release oscillation. By introducing this flowrate oscillation, how LP and φ collaboratively determine phase difference between pressure oscillation and heat release oscillation was clarified. The mechanisms identified in this study are consistent with the emerging rationalization of the factors contributing to SETAI, and also provides better understanding on Rayleigh criterion and guidance for SETAI control. With further work on heat release and flow rate measurement, as well as the development on τ description, SETAI can be better predicted and controlled.
{"title":"Experimental studies on mechanism whereby premixed chamber length and equivalence ratio collaboratively influence self‐excited thermoacoustic instability","authors":"Yuanhang Zhang, Yongbo Du, Jingkun Zhang, Defu Che","doi":"10.1002/apj.3145","DOIUrl":"https://doi.org/10.1002/apj.3145","url":null,"abstract":"Self‐excited thermoacoustic instability (SETAI) is a dangerous phenomenon in combustion equipment. While it is widely acknowledged that SETAI behavior is determined by the couple between pressure and heat release oscillation, their phase difference is difficult to predict, which impedes the development of SETAI control technology. With the aim of passive control technology development, this paper conducted experiment on a premixed hedge combustor to explore the mechanism whereby premixed chamber length (<jats:italic>L</jats:italic><jats:sub>P</jats:sub>) and equivalence ratio (<jats:italic>φ</jats:italic>) collaboratively influence SETAI behavior. Results showed <jats:italic>L</jats:italic><jats:sub>P</jats:sub> mainly affects the pressure mode shape within premixed chamber and consequently alters the phase difference between pressure and flowrate oscillation at combustion chamber inlet. Changing <jats:italic>φ</jats:italic> gives rise to different reaction time‐lag (<jats:italic>τ</jats:italic>), thus altering the phase difference between flowrate and reaction heat release oscillation. By introducing this flowrate oscillation, how <jats:italic>L</jats:italic><jats:sub>P</jats:sub> and <jats:italic>φ</jats:italic> collaboratively determine phase difference between pressure oscillation and heat release oscillation was clarified. The mechanisms identified in this study are consistent with the emerging rationalization of the factors contributing to SETAI, and also provides better understanding on Rayleigh criterion and guidance for SETAI control. With further work on heat release and flow rate measurement, as well as the development on <jats:italic>τ</jats:italic> description, SETAI can be better predicted and controlled.","PeriodicalId":8852,"journal":{"name":"Asia-Pacific Journal of Chemical Engineering","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142220363","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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