Weimin Cheng, Ke Shi, Duc-Viet Nguyen, Jianliang Xue, Qing Jiang, Di Wu, Yanlu Qiao, An Liu
{"title":"Enhancing Sulfate Reduction Efficiency in Microbial Electrolysis Cells: The Impact of Mixing Conditions and Heavy-Metal Concentrations on Functional Genes, Cell Activity, and Community Structure in Sulfate-Laden Wastewater Treatment","authors":"Weimin Cheng, Ke Shi, Duc-Viet Nguyen, Jianliang Xue, Qing Jiang, Di Wu, Yanlu Qiao, An Liu","doi":"10.1021/acsestengg.4c00421","DOIUrl":"https://doi.org/10.1021/acsestengg.4c00421","url":null,"abstract":"Microbial electrolysis cells (MECs) are promising for the treatment of sulfate-laden wastewater. The performance of the MEC cathode biofilms is influenced not only by the wastewater quality but also by the hydrodynamic mixing condition. Yet, the combined effects of these combined conditions have seldom been explored. This study examines the effectiveness and operational patterns of MECs in treating sulfate-laden wastewater under varying heavy-metal (Cu<sup>2+</sup> as representative) concentrations (0–80 mg L<sup>–1</sup>) and different hydrodynamic conditions (complete-mixing (CM) and nonmixing (NM, as control)). Results showed that CM-MECs achieved higher sulfate reduction efficiency (51 to 76%) compared to NM-MECs (with 46–69% of sulfate reduction) across the range of Cu<sup>2+</sup> concentrations. Kinetic analysis revealed that CM-MECs reduced sulfate faster due to increased expression of genes involved in sulfate reduction and electron transport. Furthermore, CM-MECs maintained intact cell structures, enhanced electron transfer, and increased the relative abundance of <i>Desulfobulbus</i> when treating wastewater with low Cu<sup>2+</sup> concentrations (<40 mg L<sup>–1</sup>). Microbial defense mechanisms against Cu<sup>2+</sup> also contributed to the enhanced sulfate reduction efficiency in the CM-MECs. These findings offer new insights into the design MECs with flowing conditions and pave the way for their future application in the treatment of heavy metal and sulfate-laden wastewater.","PeriodicalId":7008,"journal":{"name":"ACS ES&T engineering","volume":"12 1","pages":""},"PeriodicalIF":7.1,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142255865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ACS ES&T engineeringPub Date : 2024-09-17DOI: 10.1021/acsestengg.4c0042110.1021/acsestengg.4c00421
Weimin Cheng, Ke Shi, Duc-Viet Nguyen, Jianliang Xue*, Qing Jiang, Di Wu*, Yanlu Qiao and An Liu,
{"title":"Enhancing Sulfate Reduction Efficiency in Microbial Electrolysis Cells: The Impact of Mixing Conditions and Heavy-Metal Concentrations on Functional Genes, Cell Activity, and Community Structure in Sulfate-Laden Wastewater Treatment","authors":"Weimin Cheng, Ke Shi, Duc-Viet Nguyen, Jianliang Xue*, Qing Jiang, Di Wu*, Yanlu Qiao and An Liu, ","doi":"10.1021/acsestengg.4c0042110.1021/acsestengg.4c00421","DOIUrl":"https://doi.org/10.1021/acsestengg.4c00421https://doi.org/10.1021/acsestengg.4c00421","url":null,"abstract":"<p >Microbial electrolysis cells (MECs) are promising for the treatment of sulfate-laden wastewater. The performance of the MEC cathode biofilms is influenced not only by the wastewater quality but also by the hydrodynamic mixing condition. Yet, the combined effects of these combined conditions have seldom been explored. This study examines the effectiveness and operational patterns of MECs in treating sulfate-laden wastewater under varying heavy-metal (Cu<sup>2+</sup> as representative) concentrations (0–80 mg L<sup>–1</sup>) and different hydrodynamic conditions (complete-mixing (CM) and nonmixing (NM, as control)). Results showed that CM-MECs achieved higher sulfate reduction efficiency (51 to 76%) compared to NM-MECs (with 46–69% of sulfate reduction) across the range of Cu<sup>2+</sup> concentrations. Kinetic analysis revealed that CM-MECs reduced sulfate faster due to increased expression of genes involved in sulfate reduction and electron transport. Furthermore, CM-MECs maintained intact cell structures, enhanced electron transfer, and increased the relative abundance of <i>Desulfobulbus</i> when treating wastewater with low Cu<sup>2+</sup> concentrations (<40 mg L<sup>–1</sup>). Microbial defense mechanisms against Cu<sup>2+</sup> also contributed to the enhanced sulfate reduction efficiency in the CM-MECs. These findings offer new insights into the design MECs with flowing conditions and pave the way for their future application in the treatment of heavy metal and sulfate-laden wastewater.</p>","PeriodicalId":7008,"journal":{"name":"ACS ES&T engineering","volume":"5 1","pages":"1–11 1–11"},"PeriodicalIF":7.4,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143091795","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Oxygen Functionalization of Carbon Nanotubes Shifted the Formation Pathway of Hydroxyl Radicals in Catalytic Ozonation: The Overlooked Role of Hydrogen Peroxide","authors":"Yanye Tian, Yingtong Li, Guang-Guo Ying, Deli Wu, Kaimin Shih, Yong Feng","doi":"10.1021/acsestengg.4c00403","DOIUrl":"https://doi.org/10.1021/acsestengg.4c00403","url":null,"abstract":"The oxygen functionalization of multiwalled carbon nanotubes (CNTs) could enhance their reactivity in catalytic ozonation for hydroxyl radical (<sup>•</sup>OH) formation. However, the detailed pathway for the transformation of ozone to <sup>•</sup>OH and the mechanism for the decreased treatment performance at acidic pH values remain unclear. In this study, surface oxygen-functionalized CNTs (O-CNTs) were prepared and used in catalytic ozonation to reveal the pathway for <sup>•</sup>OH formation. The efficiencies of ozone utilization and its conversion to <sup>•</sup>OH were increased by 2.7 and 554.8 times, respectively, under the catalysis of the O-CNTs. The great reactivity of the O-CNTs was related to their high surface oxygen contents and increased dispersion. Hydrogen peroxide was generated as a significant intermediate during the catalytic ozonation of the O-CNTs. The exposure of this substance linearly correlated with <sup>•</sup>OH exposure and pollutant degradation constants, with correlation coefficients of 0.991 and 0.911, respectively. The formation of hydrogen peroxide was relatively slower at acidic pH values, which explains the low performance of catalytic ozonation. A mechanism was proposed that involved the generation of hydrogen peroxide to trigger the peroxone process for free <sup>•</sup>OH formation. These findings deepen our understanding of oxygen functionalization and offer insights into the catalytic ozonation of surface oxygen-rich carbonaceous materials.","PeriodicalId":7008,"journal":{"name":"ACS ES&T engineering","volume":"31 1","pages":""},"PeriodicalIF":7.1,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142256048","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ACS ES&T engineeringPub Date : 2024-09-16DOI: 10.1021/acsestengg.4c0040310.1021/acsestengg.4c00403
Yanye Tian, Yingtong Li, Guang-Guo Ying, Deli Wu, Kaimin Shih and Yong Feng*,
{"title":"Oxygen Functionalization of Carbon Nanotubes Shifted the Formation Pathway of Hydroxyl Radicals in Catalytic Ozonation: The Overlooked Role of Hydrogen Peroxide","authors":"Yanye Tian, Yingtong Li, Guang-Guo Ying, Deli Wu, Kaimin Shih and Yong Feng*, ","doi":"10.1021/acsestengg.4c0040310.1021/acsestengg.4c00403","DOIUrl":"https://doi.org/10.1021/acsestengg.4c00403https://doi.org/10.1021/acsestengg.4c00403","url":null,"abstract":"<p >The oxygen functionalization of multiwalled carbon nanotubes (CNTs) could enhance their reactivity in catalytic ozonation for hydroxyl radical (<sup>•</sup>OH) formation. However, the detailed pathway for the transformation of ozone to <sup>•</sup>OH and the mechanism for the decreased treatment performance at acidic pH values remain unclear. In this study, surface oxygen-functionalized CNTs (O-CNTs) were prepared and used in catalytic ozonation to reveal the pathway for <sup>•</sup>OH formation. The efficiencies of ozone utilization and its conversion to <sup>•</sup>OH were increased by 2.7 and 554.8 times, respectively, under the catalysis of the O-CNTs. The great reactivity of the O-CNTs was related to their high surface oxygen contents and increased dispersion. Hydrogen peroxide was generated as a significant intermediate during the catalytic ozonation of the O-CNTs. The exposure of this substance linearly correlated with <sup>•</sup>OH exposure and pollutant degradation constants, with correlation coefficients of 0.991 and 0.911, respectively. The formation of hydrogen peroxide was relatively slower at acidic pH values, which explains the low performance of catalytic ozonation. A mechanism was proposed that involved the generation of hydrogen peroxide to trigger the peroxone process for free <sup>•</sup>OH formation. These findings deepen our understanding of oxygen functionalization and offer insights into the catalytic ozonation of surface oxygen-rich carbonaceous materials.</p>","PeriodicalId":7008,"journal":{"name":"ACS ES&T engineering","volume":"4 12","pages":"3021–3031 3021–3031"},"PeriodicalIF":7.4,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142844033","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jiyun Park, Smruti Ranjan Dash, Seow Wah How, Di Wu, Jeonghwan Kim
{"title":"Anaerobic Fluidized Bed Membrane Bioreactor with Multichanneled Biocarrier for Carbon-Neutral, Decentralized Greywater Treatment","authors":"Jiyun Park, Smruti Ranjan Dash, Seow Wah How, Di Wu, Jeonghwan Kim","doi":"10.1021/acsestengg.4c00186","DOIUrl":"https://doi.org/10.1021/acsestengg.4c00186","url":null,"abstract":"This study investigated the effect of hydraulic retention times (HRTs) on the organic removal efficiency, membrane fouling, and methane production rate from an anaerobic fluidized bed membrane bioreactor (AFMBR) to treat synthetic greywater with a soluble chemical oxygen demand (SCOD) of 300 mg/L. Here, a polyvinylidene fluoride (PVDF)-based biocarrier was applied to control membrane fouling and facilitate attached biofilm growth. At an HRT of 16 h, which corresponds to 3.75 L/m<sup>2</sup> h of permeate flux, transmembrane pressure was maintained as 0.15 bar. As the HRT decreased 12 h, the SCOD removal efficiency dropped 42% quickly while bulk volatile suspended solid (VSS) concentration increased 1300 mg/L. However, when the HRT was further reduced to 8 h, the SCOD removal stabilized at 81% gradually with reducing the bulk VSS to 300 mg/L. During the entire operational period, the biogas produced by AFMBR under the fluidization of multichanneled media consisted of 50% methane. The methane yield was 0.13 L of CH<sub>4</sub>/day at an HRT of 8 h. A 16S ribosomal ribonucleic acid analysis of the microbial community demonstrated that the relative abundance of Methanosaeta grown on the PVDF media increased as the HRT decreased. Spectroscopic observation revealed that a significant portion of biomass was grown inside media channels having higher surface roughness than their outer surfaces.","PeriodicalId":7008,"journal":{"name":"ACS ES&T engineering","volume":"18 1","pages":""},"PeriodicalIF":7.1,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142256047","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Predicting Biogas Yield after Microwave Pretreatment Using Artificial Neural Network Models: Performance Evaluation and Method Comparison","authors":"Yuxuan Li, Mahuizi Lu, Luiza C. Campos, Yukun Hu","doi":"10.1021/acsestengg.4c00276","DOIUrl":"https://doi.org/10.1021/acsestengg.4c00276","url":null,"abstract":"In the field of anaerobic digestion (AD) for biogas production, accurately predicting biogas yields following microwave pretreatment (MP) remains a significant challenge. Traditional kinetic models, such as the modified Gompertz (MG) model, are widely utilized but often lack the precision and adaptability needed for optimal process design and operational efficiency. This highlights a crucial gap in the development of more accurate and flexible predictive tools. To address this gap, advanced machine learning techniques, specifically, artificial neural networks (ANN), have been explored. This study developed and evaluated three ANN models: ANN, deep feed forward backpropagation (DFFBP), and deep cascade forward backpropagation network (DCFBP). The DCFBP model demonstrated superior predictive accuracy with a high coefficient of determination (<i>R</i><sup>2</sup> = 0.9946) and a lower mean absolute error (MAE = 0.34). Key input parameters, including the ratios of volatile solids to total solids (VS/TS) and the ratio of soluble chemical oxygen demand to total chemical oxygen demand (SCOD/TCOD), were integrated to enhance the prediction precision. These findings highlight the potential of ANN models to improve biogas yield predictions, offering significant benefits for the optimization and design of AD processes.","PeriodicalId":7008,"journal":{"name":"ACS ES&T engineering","volume":"16 1","pages":""},"PeriodicalIF":7.1,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142256052","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"ACS ES&T Engineering’s 2023 Excellence in Review Awards","authors":"Wonyong Choi","doi":"10.1021/acsestengg.4c00545","DOIUrl":"https://doi.org/10.1021/acsestengg.4c00545","url":null,"abstract":"As <i>ACS ES&T Engineering</i> has entered its fourth year of publication, we take a moment to acknowledge and celebrate the exceptional contributions of our dedicated reviewers. The journal has made remarkable strides, including achieving its first Journal Impact Factor of 7.4 this year, thanks to the collective efforts of our research community. In 2023, <i>ACS ES&T Engineering</i> continued to advance as a leading platform for environmental engineering and technology research. Our impact is increasingly evident in the quality of our publications and the trust we build with authors and readers. At the heart of this progress are our reviewers, whose expert evaluations ensure the rigor and relevance of every manuscript we consider. We are delighted to honor the best reviewers of 2023, whose exceptional work has set a new standard for excellence in peer review. Their insightful critiques and thoughtful recommendations extend beyond surface-level feedback, playing a crucial role in shaping the future of environmental engineering research. Their dedication has not only upheld the high standards of <i>ACS ES&T Engineering</i> but also fostered a culture of scholarly rigor and integrity. The 2023 Excellence in Review Awards are presented to the following outstanding reviewers: <b>Wensi Chen</b>, Texas A&M University, USA, https://engineering.tamu.edu/civil/profiles/chen-wensi.html <b>Yi-Hsueh Chuang</b>, National Yang Ming Chiao Tung University, Taiwan, https://scholar.nycu.edu.tw/en/persons/yi-hsueh-chuang <b>Dahu Ding</b>, Nanjing Agricultural University, China, https://www.researchgate.net/profile/Dahu-Ding <b>Dahong Huang</b>, University of Science and Technology of China, China, https://ese.ustc.edu.cn/2022/0923/c26804a592604/page.htm <b>Samir Khanal</b>, University of Hawaii at Manoa, USA, https://www.ctahr.hawaii.edu/depart/mbbe/Khanal.html <b>Choonsoo Kim</b>, Kongju National University, Republic of Korea, https://scholar.google.de/citations?user=gbTj9OUAAAAJ&hl=en <b>Sunil Kumar</b>, National Environmental Engineering Research Institute, India, https://www.researchgate.net/profile/Sunil-Kumar-493 <b>Yu Liu</b>, Nanyang Technological University, Singapore, https://www.researchgate.net/profile/Yu-Liu-35/5 <b>Kathryn Newhart</b>, United States Military Academy at West Point, USA, https://www.westpoint.edu/geography-and-environmental-engineering/profile/kate_newhart <b>Meng Sun</b>, Tsinghua University, China, https://www.tsinghua.edu.cn/enven/info/1052/2104.htm <b>Mengye Wang</b>, Sun Yat-Sen University, China, https://www.researchgate.net/profile/Mengye-Wang <b>Xin Wang</b>, Nankai University, China, https://enven.nankai.edu.cn/wx1_en/main.htm We look forward to continuing this successful journey of publication with the support of dedicated reviewers. We extend our warmest appreciation to all of our reviewers for their loyal support in maintaining the fullest scientific rigor in our published outputs and for proudly serving ","PeriodicalId":7008,"journal":{"name":"ACS ES&T engineering","volume":"42 1","pages":""},"PeriodicalIF":7.1,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142256051","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kai He, Yuanfang Lai, Shuchen Wang, Li Gong, Feng He
{"title":"Mechanochemical Synthesis of Manganese-Modified Microscale Zerovalent Iron for Efficient Cr(VI) Removal: Performance and Mechanism","authors":"Kai He, Yuanfang Lai, Shuchen Wang, Li Gong, Feng He","doi":"10.1021/acsestengg.4c00316","DOIUrl":"https://doi.org/10.1021/acsestengg.4c00316","url":null,"abstract":"Metal doping for improving the reactivity of zerovalent iron (ZVI) has been well studied, while Mn(II)-modified microscale ZVI (Mn-mZVI) has not yet been explored. Herein, ball-milled Mn-mZVI was fabricated and used for Cr(VI) removal. Characterization analysis showed that the structure, composition, and charge of mZVI changed after the Mn(II) modification. The comparative test showed that Mn-mZVI could remove 100% of Cr(VI) within 10 min, whereas mZVI removed negligible Cr(VI) within 60 min. The zeta-potential and electrochemical evidence verified that the enhanced electrostatic attraction and electron-transfer ability contributed to the superior Cr(VI) removal performance of Mn-mZVI. Moreover, the solution pH increase caused the decline of Cr(VI) removal, and the presence of NO<sub>3</sub><sup>–</sup> inhibited Cr(VI) removal, whereas other coexisting ions showed little influence on the Cr(VI) removal performance of Mn-mZVI. Chemical and material characterization analyses revealed that Cr(VI) reduction by Mn-mZVI was the combined action of Fe(0) and generated Fe(II). In addition, the reusability of Mn-mZVI was not ideal due to the surface passivation and loss of Mn(II), but the reactivity could be reactivated by ball-milling the reacted Mn-mZVI again with Mn(II). Overall, this work provides a new mentality for mZVI modification and is important to develop promising mZVI-based materials for Cr(VI) pollution control.","PeriodicalId":7008,"journal":{"name":"ACS ES&T engineering","volume":"73 1","pages":""},"PeriodicalIF":7.1,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142256049","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Machine Learning toward Realizing End-to-End Biochar Design for Environmental Remediation","authors":"Rupeng Wang, Honglin Chen, Silin Guo, Zixiang He, Nanqi Ren, Shih-Hsin Ho","doi":"10.1021/acsestengg.4c00267","DOIUrl":"https://doi.org/10.1021/acsestengg.4c00267","url":null,"abstract":"Developing algorithmic methodologies for the rational design of environmental functional materials enables targeted approaches to environmental challenges. Novel machine learning (ML) tools are instrumental in realizing this goal, particularly when biochars are involved with complex components and flexible internal structures. However, such rational design necessitates a holistic perspective across the entire multistage design process, while current ML endeavors for environmental biochar (EB) often concentrate on specific production or application substages. In this regard, taking an end-to-end (E2E) approach to applying ML holds the potential to better guide EB design from a comprehensive view, a perspective yet to be thoroughly explored and summarized. Thus, we review the recent advancements of ML employed in predicting EB problems, aiming to elucidate the broad relevance of various ML models in realizing the E2E design of EBs. It is observed that the properties of EB might be the “Achilles’ heel” within the data set, which poses a significant challenge to achieving the E2E. Furthermore, we also provide an overview of the existing pathways to achieve the E2E, examining both traditional ML and the emerging field of deep leaning, followed by a discussion on key challenges, opportunities, and our vision for the future of rational EB design.","PeriodicalId":7008,"journal":{"name":"ACS ES&T engineering","volume":"12 1","pages":""},"PeriodicalIF":7.1,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142256050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}