Zeinab Gholamnejad, Golnoosh Abdeali, Ahmad Reza Bahramian
In various industrial applications, especially within the internal pipes of heat exchanger devices, there is a crucial need for surface coatings that offer both superhydrophobic properties and high thermal conductivity. Achieving the balance between these two characteristics is essential for optimizing heat transfer performance along metal pipe walls and mitigating the formation of water droplets on the surface. This research focuses on the development of polymer composite coatings to address these dual requirements, providing protection against humid environments, resistance to dew formation, and simultaneous enhancement of thermal conductivity. The key challenge lies in selecting a coating type that provides low surface energy and polarity, thereby achieving the desired hydrophobic properties while also maintaining adequate thermal conductivity. This study formulates polymer composite coatings utilizing laser‐modified epoxy resin and strategically integrates graphite oxide particles. These graphite particles undergo modification through oxidation to enhance compatibility with epoxy. In conjunction with graphite oxide modification, the resulting laser‐modified coatings exhibit super‐hydrophobic characteristics with an enhanced water contact angle of 162° and a low contact angle hysteresis (<5°). Furthermore, the epoxy/graphite oxide composite coatings demonstrate improved thermal conductivity, marking a significant 261% increase compared to pure epoxy, elevating it from .234 to .846 W/mK.
{"title":"Assessment of the synergy of hydrophobicity and thermal conductivity in epoxy/graphite oxide composite coatings","authors":"Zeinab Gholamnejad, Golnoosh Abdeali, Ahmad Reza Bahramian","doi":"10.1002/apj.3133","DOIUrl":"https://doi.org/10.1002/apj.3133","url":null,"abstract":"In various industrial applications, especially within the internal pipes of heat exchanger devices, there is a crucial need for surface coatings that offer both superhydrophobic properties and high thermal conductivity. Achieving the balance between these two characteristics is essential for optimizing heat transfer performance along metal pipe walls and mitigating the formation of water droplets on the surface. This research focuses on the development of polymer composite coatings to address these dual requirements, providing protection against humid environments, resistance to dew formation, and simultaneous enhancement of thermal conductivity. The key challenge lies in selecting a coating type that provides low surface energy and polarity, thereby achieving the desired hydrophobic properties while also maintaining adequate thermal conductivity. This study formulates polymer composite coatings utilizing laser‐modified epoxy resin and strategically integrates graphite oxide particles. These graphite particles undergo modification through oxidation to enhance compatibility with epoxy. In conjunction with graphite oxide modification, the resulting laser‐modified coatings exhibit super‐hydrophobic characteristics with an enhanced water contact angle of 162° and a low contact angle hysteresis (<5°). Furthermore, the epoxy/graphite oxide composite coatings demonstrate improved thermal conductivity, marking a significant 261% increase compared to pure epoxy, elevating it from .234 to .846 W/mK.","PeriodicalId":8852,"journal":{"name":"Asia-Pacific Journal of Chemical Engineering","volume":"21 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142220403","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}
Carys M. Bloomfield, Chi M. Phan, Malik M. Mohammed, Ammar Al Helal
The management and prevention of hydrates are crucial for the gas industry. This study delves into the intricate challenges associated with gas hydrate formation, with a specific focus on investigating the impact of corrosion by‐products on prevention strategies. Employing a distinctive methodology, the sapphire pressure–volume temperature (PVT) cell was utilized. Experimental tests were conducted using sodium chloride (NaCl) concentrations of 1% and 3% to simulate brine solution levels at the wellhead, incorporating 3% filtrate and unfiltered iron carbonate (FeCO3) as corrosion products associated with the production process. The 1% and 3% salt concentrations were chosen to encompass a broad range of temperature depressions, reflecting common industry standards for simulating realistic environmental conditions. PVT cell test conditions ranged from 80 to 200 bar, with increments of 40 bar. The experiments investigate the effects of common pipeline salts on a monoethylene glycol (MEG)/water mixture in the presence of methane gas at typical industry high‐pressure conditions. The investigation uncovers that the introduction of salts to water, methane, and MEG solutions serves as a hydrate inhibitor, with inhibitory effects directly correlated to salt concentration. While generally hydrate growth inhibition is beneficial in natural gas pipelines, the findings indicate that elevated salt concentrations and lower pressure conditions contribute to the formation of larger hydrates, heightening the risk of surface adhesion and potentially introducing complications in piping equipment, despite the decreased temperature at which these hydrates form due to the inhibitory effects of the salts. In particular, the mixed condition of 3% NaCl and 3% FeCO3 (filtered) has the strongest effect. Examination of hydrate formation temperature and macroscopic observations suggests that the existence of substantial precipitates, as evidenced in the unfiltered FeCO3 sapphire cell experiment, may have the potential to enhance hydrate growth.
{"title":"Evaluating the impact of sodium chloride and iron carbonate ions on gas hydrate formation in Monoethylene Glycol‐enhanced aqueous solutions","authors":"Carys M. Bloomfield, Chi M. Phan, Malik M. Mohammed, Ammar Al Helal","doi":"10.1002/apj.3139","DOIUrl":"https://doi.org/10.1002/apj.3139","url":null,"abstract":"The management and prevention of hydrates are crucial for the gas industry. This study delves into the intricate challenges associated with gas hydrate formation, with a specific focus on investigating the impact of corrosion by‐products on prevention strategies. Employing a distinctive methodology, the sapphire pressure–volume temperature (PVT) cell was utilized. Experimental tests were conducted using sodium chloride (NaCl) concentrations of 1% and 3% to simulate brine solution levels at the wellhead, incorporating 3% filtrate and unfiltered iron carbonate (FeCO<jats:sub>3</jats:sub>) as corrosion products associated with the production process. The 1% and 3% salt concentrations were chosen to encompass a broad range of temperature depressions, reflecting common industry standards for simulating realistic environmental conditions. PVT cell test conditions ranged from 80 to 200 bar, with increments of 40 bar. The experiments investigate the effects of common pipeline salts on a monoethylene glycol (MEG)/water mixture in the presence of methane gas at typical industry high‐pressure conditions. The investigation uncovers that the introduction of salts to water, methane, and MEG solutions serves as a hydrate inhibitor, with inhibitory effects directly correlated to salt concentration. While generally hydrate growth inhibition is beneficial in natural gas pipelines, the findings indicate that elevated salt concentrations and lower pressure conditions contribute to the formation of larger hydrates, heightening the risk of surface adhesion and potentially introducing complications in piping equipment, despite the decreased temperature at which these hydrates form due to the inhibitory effects of the salts. In particular, the mixed condition of 3% NaCl and 3% FeCO<jats:sub>3</jats:sub> (filtered) has the strongest effect. Examination of hydrate formation temperature and macroscopic observations suggests that the existence of substantial precipitates, as evidenced in the unfiltered FeCO<jats:sub>3</jats:sub> sapphire cell experiment, may have the potential to enhance hydrate growth.","PeriodicalId":8852,"journal":{"name":"Asia-Pacific Journal of Chemical Engineering","volume":"286 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142220372","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}
Adewale George Adeniyi, Sulyman Age Abdulkareem, Kingsley O. Iwuozor, Omar H. Abd-Elkader, Mubarak A. Amoloye, Ebuka Chizitere Emenike, Ebenezer O. Omonayin, Ifeoluwa Peter Oyekunle, Abdelrahman O. Ezzat
This research explored the characteristics of polymer composites reinforced with orange peel biochar. The composites were created using the hand lay-up method with different filler ratios, cured at ambient temperature, and analyzed with various analytical techniques, including scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, and energy dispersive X-ray spectroscopy (EDX). SEM images showed that roughness increased with higher filler percentages. FTIR analysis detected functional groups like OH, COOH, and aromatic compounds in the composites, primarily inheriting these groups from the resin. Elemental analysis using EDX indicated that the composites contained carbon, oxygen, silicon, aluminum, and potassium. Among these elements, only the carbon concentration demonstrated a linear increase with rising filler levels, with the composite containing 40% biochar achieving the highest carbon content at 84%. Hardness testing showed that the physical strength of the composites increased as the polystyrene resin matrix was reinforced, with the 40% biochar composite exhibiting a maximum hardness value of 296 N. These results indicate that adding biochar not only enhanced the properties of polystyrene-based composites but also reduced their environmental impact.
{"title":"Development of green polystyrene composites using Citrus sinensis biochar filler","authors":"Adewale George Adeniyi, Sulyman Age Abdulkareem, Kingsley O. Iwuozor, Omar H. Abd-Elkader, Mubarak A. Amoloye, Ebuka Chizitere Emenike, Ebenezer O. Omonayin, Ifeoluwa Peter Oyekunle, Abdelrahman O. Ezzat","doi":"10.1002/apj.3140","DOIUrl":"https://doi.org/10.1002/apj.3140","url":null,"abstract":"This research explored the characteristics of polymer composites reinforced with orange peel biochar. The composites were created using the hand lay-up method with different filler ratios, cured at ambient temperature, and analyzed with various analytical techniques, including scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, and energy dispersive X-ray spectroscopy (EDX). SEM images showed that roughness increased with higher filler percentages. FTIR analysis detected functional groups like <span></span>OH, <span></span>COOH, and aromatic compounds in the composites, primarily inheriting these groups from the resin. Elemental analysis using EDX indicated that the composites contained carbon, oxygen, silicon, aluminum, and potassium. Among these elements, only the carbon concentration demonstrated a linear increase with rising filler levels, with the composite containing 40% biochar achieving the highest carbon content at 84%. Hardness testing showed that the physical strength of the composites increased as the polystyrene resin matrix was reinforced, with the 40% biochar composite exhibiting a maximum hardness value of 296 N. These results indicate that adding biochar not only enhanced the properties of polystyrene-based composites but also reduced their environmental impact.","PeriodicalId":8852,"journal":{"name":"Asia-Pacific Journal of Chemical Engineering","volume":"38 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142220373","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 practical application of traditional data‐driven techniques for process monitoring encounters significant challenges due to the inherent nonlinear and dynamic nature of most industrial processes. Aiming at the problem of nonlinear dynamic process monitoring, a novel fault detection method based on dynamic kernel principal component analysis combined with weighted structural difference (DKPCA‐WSD) is proposed in this paper. Initially, the proposed method leverages a sophisticated nonlinear transformation to project the augmented matrix of the original input data into a high‐dimensional feature space, thereby facilitating the establishment of a DKPCA model. Subsequently, the WSD statistic is computed, utilizing a widely known sliding window technique, to quantify the mean and standard deviation differences across data structures. Ultimately, the WSD statistic is utilized for fault detection, completing the process monitoring task. By integrating the capability of DKPCA to capture nonlinear dynamic characteristics with the effectiveness of the WSD statistic in mitigating the impact of non‐Gaussian data distributions, DKPCA‐WSD significantly enhances the monitoring performance of traditional DKPCA in nonlinear dynamic processes. The proposed method is evaluated through a numerical case exhibiting nonlinear dynamic behaviors and a simulation model of a continuous stirred tank reactor. A comparative analysis with conventional methods, including principal component analysis (PCA), dynamic principal component analysis, KPCA, PCA similarity factor (SPCA), DKPCA, and moving window KPCA (MWKPCA), demonstrates that DKPCA‐WSD outperforms traditional fault detection techniques in nonlinear dynamic processes, offering a substantial improvement in monitoring performance.
{"title":"Industrial process fault detection based on dynamic kernel principal component analysis combined with weighted structural difference","authors":"Cheng Zhang, Feng Yan, Chenglong Deng, Yuan Li","doi":"10.1002/apj.3132","DOIUrl":"https://doi.org/10.1002/apj.3132","url":null,"abstract":"The practical application of traditional data‐driven techniques for process monitoring encounters significant challenges due to the inherent nonlinear and dynamic nature of most industrial processes. Aiming at the problem of nonlinear dynamic process monitoring, a novel fault detection method based on dynamic kernel principal component analysis combined with weighted structural difference (DKPCA‐WSD) is proposed in this paper. Initially, the proposed method leverages a sophisticated nonlinear transformation to project the augmented matrix of the original input data into a high‐dimensional feature space, thereby facilitating the establishment of a DKPCA model. Subsequently, the WSD statistic is computed, utilizing a widely known sliding window technique, to quantify the mean and standard deviation differences across data structures. Ultimately, the WSD statistic is utilized for fault detection, completing the process monitoring task. By integrating the capability of DKPCA to capture nonlinear dynamic characteristics with the effectiveness of the WSD statistic in mitigating the impact of non‐Gaussian data distributions, DKPCA‐WSD significantly enhances the monitoring performance of traditional DKPCA in nonlinear dynamic processes. The proposed method is evaluated through a numerical case exhibiting nonlinear dynamic behaviors and a simulation model of a continuous stirred tank reactor. A comparative analysis with conventional methods, including principal component analysis (PCA), dynamic principal component analysis, KPCA, PCA similarity factor (SPCA), DKPCA, and moving window KPCA (MWKPCA), demonstrates that DKPCA‐WSD outperforms traditional fault detection techniques in nonlinear dynamic processes, offering a substantial improvement in monitoring performance.","PeriodicalId":8852,"journal":{"name":"Asia-Pacific Journal of Chemical Engineering","volume":"25 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141944517","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 problem of nitrogen oxide (NOx) emissions has attracted wide attention in the field of environmental protection. The effects of sodium hydroxide (NaOH), hydrogen peroxide (H2O2), phenol (C6H5OH) and ethanol (C2H6OH) on the denitration activity of selective non‐catalytic reduction (SNCR) and the emission of secondary pollutants nitrous oxide (N2O) and carbon monoxide (CO) were investigated. Results indicated that the addition of NaOH, phenol and ethanol can improve the denitration efficiency under low temperature by providing OH. From 650°C to 750°C, ethanol had the best effect, with the denitration efficiency of 30%. From 750°C to 850°C, the denitration efficiency of phenol was 40% ~ 50%. The introduction of phenol and ethanol would increase the N2O and CO emissions. From 700°C to 800°C, hydrogen peroxide only caused a small amount of N2O emissions and had no significant effect on CO.
{"title":"Effect of liquid additives on the low temperature denitration activity of SNCR and emission characteristics of N2O and CO","authors":"Wenxi Ding, Menglian Liu, Jun Wan, Wei Liu, Jiliang Ma, Yufeng Duan","doi":"10.1002/apj.3138","DOIUrl":"https://doi.org/10.1002/apj.3138","url":null,"abstract":"The problem of nitrogen oxide (NOx) emissions has attracted wide attention in the field of environmental protection. The effects of sodium hydroxide (NaOH), hydrogen peroxide (H2O2), phenol (C6H5OH) and ethanol (C2H6OH) on the denitration activity of selective non‐catalytic reduction (SNCR) and the emission of secondary pollutants nitrous oxide (N2O) and carbon monoxide (CO) were investigated. Results indicated that the addition of NaOH, phenol and ethanol can improve the denitration efficiency under low temperature by providing OH. From 650°C to 750°C, ethanol had the best effect, with the denitration efficiency of 30%. From 750°C to 850°C, the denitration efficiency of phenol was 40% ~ 50%. The introduction of phenol and ethanol would increase the N2O and CO emissions. From 700°C to 800°C, hydrogen peroxide only caused a small amount of N2O emissions and had no significant effect on CO.","PeriodicalId":8852,"journal":{"name":"Asia-Pacific Journal of Chemical Engineering","volume":"49 17","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141929350","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}
Soen Steven, Pandit Hernowo, Nugroho A. Sasongko, Adik A. Soedarsono, Maya L. D. Wardani, Geby Otivriyanti, Ernie S. A. Soekotjo, Ibnu M. Hidayatullah, Intan C. Sophiana, Neng T. U. Culsum, Imam M. Fajri, Pasymi Pasymi, Yazid Bindar
Computational fluid dynamics (CFD) is a powerful tool to provide information on detailed turbulent flow in unit processes. For that reason, this study intends to reveal the flow structures in the horizontal pipe and biomass combustor. The simulation was aided by ANSYS Fluent employing standard ‐ model. The results show that a greater Reynolds number generates more turbulence. The pressure drop inside the pipe is also found steeper for small pipe diameters following Fanning's correlation. The fully developed flow for the laminar regime is found in locations where the ratio of entrance length to pipe diameter complies with Hagen–Poiseuille's rule. The sucking phenomenon in jet flow is also similar to the working principle of ejector. For the biomass combustor, the average combustion temperature is 356–696°C, and the maximum flame temperature is 1587–1697°C. Subsequently, air initially flows through the burner area and then moves to the outlet when enters the combustor chamber. Not so for particle flow, the particle experiences sedimentation in the burner area and then falls as it enters the combustor chamber. This study also convinces that secondary air supply can produce more circulating effects in the combustor.
{"title":"Revealing flow structures in horizontal pipe and biomass combustor using computational fluid dynamics simulation","authors":"Soen Steven, Pandit Hernowo, Nugroho A. Sasongko, Adik A. Soedarsono, Maya L. D. Wardani, Geby Otivriyanti, Ernie S. A. Soekotjo, Ibnu M. Hidayatullah, Intan C. Sophiana, Neng T. U. Culsum, Imam M. Fajri, Pasymi Pasymi, Yazid Bindar","doi":"10.1002/apj.3137","DOIUrl":"https://doi.org/10.1002/apj.3137","url":null,"abstract":"Computational fluid dynamics (CFD) is a powerful tool to provide information on detailed turbulent flow in unit processes. For that reason, this study intends to reveal the flow structures in the horizontal pipe and biomass combustor. The simulation was aided by ANSYS Fluent employing standard ‐ model. The results show that a greater Reynolds number generates more turbulence. The pressure drop inside the pipe is also found steeper for small pipe diameters following Fanning's correlation. The fully developed flow for the laminar regime is found in locations where the ratio of entrance length to pipe diameter complies with Hagen–Poiseuille's rule. The sucking phenomenon in jet flow is also similar to the working principle of ejector. For the biomass combustor, the average combustion temperature is 356–696°C, and the maximum flame temperature is 1587–1697°C. Subsequently, air initially flows through the burner area and then moves to the outlet when enters the combustor chamber. Not so for particle flow, the particle experiences sedimentation in the burner area and then falls as it enters the combustor chamber. This study also convinces that secondary air supply can produce more circulating effects in the combustor.","PeriodicalId":8852,"journal":{"name":"Asia-Pacific Journal of Chemical Engineering","volume":"26 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141944519","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}
Lichao Ge, Longhui Mai, Qian Li, Nai Rong, Yang Wang, Qingyuan Yang, Hongda Song, Chang Xu
Rolling oil sludge (ROS) is a type of solid waste produced during steel rolling; this waste contains not only a high iron content but also many harmful organic components and is a very attractive secondary resource. This paper introduces the sources and hazards of ROS, summarizes the recycling methods integrated with steel production, classifies traditional treatment technologies, and analyzes their advantages and disadvantages. Combined treatment is the main direction of ROS treatment methods in the future. The ROS recycling techniques applied in different industries are summarized. Finally, existing problems and future work are described to promote the remediation and resource utilization of ROS.
{"title":"Current research status and development trends in rolling oil sludge treatment","authors":"Lichao Ge, Longhui Mai, Qian Li, Nai Rong, Yang Wang, Qingyuan Yang, Hongda Song, Chang Xu","doi":"10.1002/apj.3135","DOIUrl":"https://doi.org/10.1002/apj.3135","url":null,"abstract":"Rolling oil sludge (ROS) is a type of solid waste produced during steel rolling; this waste contains not only a high iron content but also many harmful organic components and is a very attractive secondary resource. This paper introduces the sources and hazards of ROS, summarizes the recycling methods integrated with steel production, classifies traditional treatment technologies, and analyzes their advantages and disadvantages. Combined treatment is the main direction of ROS treatment methods in the future. The ROS recycling techniques applied in different industries are summarized. Finally, existing problems and future work are described to promote the remediation and resource utilization of ROS.","PeriodicalId":8852,"journal":{"name":"Asia-Pacific Journal of Chemical Engineering","volume":"41 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141944520","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}
J. X. Tan, K. Foo, W. J. Lau, S. F. Chua, M. H. Ab Rahim, A. L. Ahmad, Y. Y. Liang
Feed spacers improve mixing and mass transfer in membrane modules. However, they also lead to foulant deposition in the vicinity of the spacer surface. In this paper, two hydrophilic monomers, namely, acrylic acid (AA) and 2‐hydroxyethyl methacrylate (HEMA), are respectively coated on the surface of a commercial feed spacer via a plasma‐enhanced chemical vapor deposition (PECVD) method. The resulting modified spacers are then evaluated alongside with a reverse osmosis (RO) membrane for its solute rejection, water permeability, and antifouling properties. Results show that the surface hydrophilicity of feed spacers has been enhanced upon the AA and HEMA deposition. During filtration test, the HEMA‐modified spacer demonstrates higher flux recovery rate (94.17%) and salt rejection (95.78%) for the RO membrane. In contrast, the membrane with the unmodified spacer only shows 89.44% and 92.46%, respectively. Additionally, the membrane with the HEMA‐modified spacer has a thinner fouling layer (200 nm) compared to the unmodified spacer (700 nm). The HEMA‐coated spacer outperforms all the tested spacers, demonstrating that feed spacer modification with a hydrophilic monomer via the PECVD method can effectively reduce membrane fouling.
进料隔板可改善膜组件中的混合和传质。然而,它们也会导致污物在间隔物表面附近沉积。本文通过等离子体增强化学气相沉积(PECVD)方法,将两种亲水性单体,即丙烯酸(AA)和甲基丙烯酸羟乙酯(HEMA),分别涂覆在商用给料间隔物表面。然后对改性后的隔膜和反渗透膜进行了溶质截留、透水性和防污性能评估。结果表明,在 AA 和 HEMA 沉积后,进料间隔物的表面亲水性得到了增强。在过滤测试中,经 HEMA 改性的反渗透膜具有更高的通量回收率(94.17%)和盐排斥率(95.78%)。相比之下,使用未改性间隔物的反渗透膜仅分别达到 89.44% 和 92.46%。此外,使用 HEMA 改性间隔物的膜与未改性间隔物(700 纳米)相比,污垢层更薄(200 纳米)。HEMA 涂层间隔物的性能优于所有测试过的间隔物,这表明通过 PECVD 方法用亲水单体对进料间隔物进行改性可有效减少膜污垢。
{"title":"Hydrophilic modification of feed spacer and its impacts on antifouling performance of reverse osmosis membrane","authors":"J. X. Tan, K. Foo, W. J. Lau, S. F. Chua, M. H. Ab Rahim, A. L. Ahmad, Y. Y. Liang","doi":"10.1002/apj.3134","DOIUrl":"https://doi.org/10.1002/apj.3134","url":null,"abstract":"Feed spacers improve mixing and mass transfer in membrane modules. However, they also lead to foulant deposition in the vicinity of the spacer surface. In this paper, two hydrophilic monomers, namely, acrylic acid (AA) and 2‐hydroxyethyl methacrylate (HEMA), are respectively coated on the surface of a commercial feed spacer via a plasma‐enhanced chemical vapor deposition (PECVD) method. The resulting modified spacers are then evaluated alongside with a reverse osmosis (RO) membrane for its solute rejection, water permeability, and antifouling properties. Results show that the surface hydrophilicity of feed spacers has been enhanced upon the AA and HEMA deposition. During filtration test, the HEMA‐modified spacer demonstrates higher flux recovery rate (94.17%) and salt rejection (95.78%) for the RO membrane. In contrast, the membrane with the unmodified spacer only shows 89.44% and 92.46%, respectively. Additionally, the membrane with the HEMA‐modified spacer has a thinner fouling layer (200 nm) compared to the unmodified spacer (700 nm). The HEMA‐coated spacer outperforms all the tested spacers, demonstrating that feed spacer modification with a hydrophilic monomer via the PECVD method can effectively reduce membrane fouling.","PeriodicalId":8852,"journal":{"name":"Asia-Pacific Journal of Chemical Engineering","volume":"14 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141944518","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}
Quang Minh Tran, Phuong Thu Le, Thu Phuong Nguyen, Hong Nam Nguyen, Thi Hai Do, Trung Dung Nguyen, Thi Mai Thanh Dinh
Biochar (BC) and hydroxyapatite (HAp) are widely used in environmental remediation due to their high adsorption capacity, porous structure, large specific surface area, chemical stability, non‐toxicity, and low solubility. Combining BC and HAp is a green and effective strategy for creating new adsorbents (BCH) that have a synergistic impact on wastewater treatment. In this study, BCH composites derived from apatite ore and macadamia nut shells were synthesized by the wet impregnation method to remove oxytetracycline (OTC) from aqueous solutions. The BC‐HAp composite with a ratio of 10:1 (by weight) was the most effective material for removing OTC. The Redlich–Peterson model achieved the highest correlation coefficient among the four models tested (Freundlich, Langmuir, Temkin, and Redlich–Peterson). The maximum adsorption capacity calculated with the Langmuir isotherm was 49.59 mg g−1. It was found that the adsorption process was significantly affected by the solution pH. The bipolar form of the drug was found to be OTC±, and the adsorption was most effective in solutions with a pH of 6. The OTC adsorption dominant mechanisms on nanocomposites could be electrostatic attraction, hydrogen bonding formation, surface complexation, or ion exchange. Therefore, the BCH composite showed great potential for removing OTC pollutants in a cost‐effective, and environmentally friendly manner.
{"title":"Efficient removal of emerging pollutant oxytetracycline by cost‐effective biochar–hydroxyapatite composite","authors":"Quang Minh Tran, Phuong Thu Le, Thu Phuong Nguyen, Hong Nam Nguyen, Thi Hai Do, Trung Dung Nguyen, Thi Mai Thanh Dinh","doi":"10.1002/apj.3124","DOIUrl":"https://doi.org/10.1002/apj.3124","url":null,"abstract":"Biochar (BC) and hydroxyapatite (HAp) are widely used in environmental remediation due to their high adsorption capacity, porous structure, large specific surface area, chemical stability, non‐toxicity, and low solubility. Combining BC and HAp is a green and effective strategy for creating new adsorbents (BCH) that have a synergistic impact on wastewater treatment. In this study, BCH composites derived from apatite ore and macadamia nut shells were synthesized by the wet impregnation method to remove oxytetracycline (OTC) from aqueous solutions. The BC‐HAp composite with a ratio of 10:1 (by weight) was the most effective material for removing OTC. The Redlich–Peterson model achieved the highest correlation coefficient among the four models tested (Freundlich, Langmuir, Temkin, and Redlich–Peterson). The maximum adsorption capacity calculated with the Langmuir isotherm was 49.59 mg g<jats:sup>−1</jats:sup>. It was found that the adsorption process was significantly affected by the solution pH. The bipolar form of the drug was found to be OTC<jats:sup>±</jats:sup>, and the adsorption was most effective in solutions with a pH of 6. The OTC adsorption dominant mechanisms on nanocomposites could be electrostatic attraction, hydrogen bonding formation, surface complexation, or ion exchange. Therefore, the BCH composite showed great potential for removing OTC pollutants in a cost‐effective, and environmentally friendly manner.","PeriodicalId":8852,"journal":{"name":"Asia-Pacific Journal of Chemical Engineering","volume":"1419 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141866049","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}
Thermal runaway of polymerization reactions causes serious accidents. To study the emergency inhibition process of thermal runaway, a styrene thermal polymerization reaction model is established by using computational fluid dynamics (CFD) combined with a thermodynamic model. The DIV critical criterion is used to determine the critical point of the runaway reaction. The inhibitory effect of injection diameter, injection rate, and injection angle of inhibitor (ethylbenzene) on the styrene polymerization reaction is studied comprehensively. The injection mixing trajectory of the inhibitor is visualized by using the Lagrangian particle tracking method. The injection parameters are optimized to suppress thermal runaway by the response surface method. The result shows that a combination of injection parameters with 2 mm injection port diameter, 5 m/s injection rate, and 90° injection angle can improve the suppression effect of thermal runaway for the established model in this paper. This work provides a theoretical basis for preventing thermal runaway for polymerization reactions.
聚合反应的热失控会导致严重事故。为了研究热失控的紧急抑制过程,利用计算流体动力学(CFD)结合热力学模型建立了苯乙烯热聚合反应模型。采用 DIV 临界准则确定失控反应的临界点。全面研究了抑制剂(乙苯)的注入直径、注入速率和注入角度对苯乙烯聚合反应的抑制作用。采用拉格朗日粒子跟踪方法对抑制剂的注入混合轨迹进行了可视化分析。采用响应面法优化了注入参数,以抑制热失控。结果表明,在本文建立的模型中,喷射口直径为 2 毫米、喷射速度为 5 米/秒、喷射角度为 90°的喷射参数组合可以提高抑制热失控的效果。这项工作为防止聚合反应热失控提供了理论依据。
{"title":"CFD simulation study of thermal runaway inhibition for styrene polymerization by jet mixing","authors":"Jiajia Jiang, Yating Chen, Rui Zhou, Guanrong Mao","doi":"10.1002/apj.3129","DOIUrl":"https://doi.org/10.1002/apj.3129","url":null,"abstract":"Thermal runaway of polymerization reactions causes serious accidents. To study the emergency inhibition process of thermal runaway, a styrene thermal polymerization reaction model is established by using computational fluid dynamics (CFD) combined with a thermodynamic model. The DIV critical criterion is used to determine the critical point of the runaway reaction. The inhibitory effect of injection diameter, injection rate, and injection angle of inhibitor (ethylbenzene) on the styrene polymerization reaction is studied comprehensively. The injection mixing trajectory of the inhibitor is visualized by using the Lagrangian particle tracking method. The injection parameters are optimized to suppress thermal runaway by the response surface method. The result shows that a combination of injection parameters with 2 mm injection port diameter, 5 m/s injection rate, and 90° injection angle can improve the suppression effect of thermal runaway for the established model in this paper. This work provides a theoretical basis for preventing thermal runaway for polymerization reactions.","PeriodicalId":8852,"journal":{"name":"Asia-Pacific Journal of Chemical Engineering","volume":"45 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141866156","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}