ACS ES&T engineering最新文献

{"title":"Long Lifetime and High Reusability of Water Toxicity Determination Based on Electrochemically Active Bacteria","authors":"Yue Yi,&nbsp;Yuxin Feng,&nbsp;Xuemei Yi,&nbsp;Fan Zha,&nbsp;Zikai Hao,&nbsp;Dandan Yu,&nbsp;Hong Liu,&nbsp;Yanhong Ge* and Aiqin Luo*,&nbsp;","doi":"10.1021/acsestengg.4c0054810.1021/acsestengg.4c00548","DOIUrl":"https://doi.org/10.1021/acsestengg.4c00548https://doi.org/10.1021/acsestengg.4c00548","url":null,"abstract":"<p >Toxicity determination based on electrochemically active bacteria (EAB) shows great prospects for early warning of water pollution. However, the lifetime and reusability of EAB in toxicity determination remain uncertain. This study performed continuous toxicity determination by using an automatic water toxicity determination system based on EAB. Results demonstrated that EAB are capable of rapid responses to common heavy metal pollutants and make a full recovery after refreshment. Despite changes in microbial communities, EAB maintain a similar current generation capacity and toxicity sensitivity even after 20 continuous toxicity tests. The main reason for the stable performance was unchanged gene functions, as the toxicity tests did not result in a decrease in genes related to current generation or an increase in genes related to resistance. This study first reported that EAB possess a prolonged lifetime and good reusability in water toxicity determination, providing a basis for the continuous determination for water toxicity and the online monitoring of industrial wastewater toxicity based on EAB.</p>","PeriodicalId":7008,"journal":{"name":"ACS ES&T engineering","volume":"5 2","pages":"414–423 414–423"},"PeriodicalIF":7.4,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143402101","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":"Emerging Feammox Technology: Mechanisms, Biotechnological Applications, and Future Prospects","authors":"Ke Shi,&nbsp;Jianfeng Ju,&nbsp;Mohamed Elsamadony,&nbsp;Manabu Fujii,&nbsp;Jibao Liu,&nbsp;Juan Qin,&nbsp;Zhipeng Liao* and Changjin Ou*,&nbsp;","doi":"10.1021/acsestengg.4c0052510.1021/acsestengg.4c00525","DOIUrl":"https://doi.org/10.1021/acsestengg.4c00525https://doi.org/10.1021/acsestengg.4c00525","url":null,"abstract":"<p >Feammox, an innovative and energy-efficient biological ammonium removal technology, has attracted significant attention in recent years. Defined as the anaerobic ammonium oxidation coupled with Fe(III) reduction, Feammox involves Fe(III)-reducing microbes that oxidize ammonium to nitrite using ferric ions. Identified in diverse ecosystems, such as freshwater, marine, natural wetlands, and wastewater ecosystems, Feammox plays a vital role in the global nitrogen cycle. Numerous studies have investigated its performance, influencing factors, reaction mechanisms, and engineering applications. However, our understanding of the functional microorganisms and key genes involved in Feammox remains limited and controversial. Clearly identifying and characterizing the functional microorganisms responsible for the Feammox process are essential for its practical application in wastewater treatment. Therefore, this review critically analyzes and summarizes recent advances in Feammox research, with a focus on functional microorganisms, key genes, and regulation strategies. Initially, the review discusses the functional microorganisms of Feammox from the perspective of microbial cooperation. It then delves into the enzymatic and genetic mechanisms involved as well as the critical factors affecting Feammox microbial activity. Finally, regulation strategies to enhance the Feammox efficiency are systematically outlined. This comprehensive analysis of current Feammox research provides a clearer and more complete understanding of microbial Feammox, deepens the knowledge of its mechanisms, and establishes a solid foundation for its engineering application.</p>","PeriodicalId":7008,"journal":{"name":"ACS ES&T engineering","volume":"4 12","pages":"2856–2873 2856–2873"},"PeriodicalIF":7.4,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142843233","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":"Manipulating the Selective Generation of Hydroxyl Radicals by Nitrogen-Doped Carbon Catalysts for Efficient Fenton-Like Reactions","authors":"Meirong Wu,&nbsp;Jiexiang Li,&nbsp;Wei Sun and Yue Yang*,&nbsp;","doi":"10.1021/acsestengg.4c0039010.1021/acsestengg.4c00390","DOIUrl":"https://doi.org/10.1021/acsestengg.4c00390https://doi.org/10.1021/acsestengg.4c00390","url":null,"abstract":"<p >Hydroxyl radical (^•OH)-dominated Fenton-like reactions offer a promising strategy for the degradation of refractory organic pollutants. However, the application of nitrogen-doped carbon (NC) catalysts for ^•OH generation is hindered by the loss of active nitrogen species during high-temperature synthesis (900–1200 °C), and an effective strategy to promote the homolytic cleavage of hydrogen peroxide (H₂O₂) remains necessary. Herein, an NC catalyst with abundant active nitrogen for enhanced ^•OH generation was prepared from zeolitic imidazolate frameworks by low-temperature pyrolysis at 800 °C, followed by acid-washing. Theoretical calculations and experimental results demonstrated that pyridinic and pyrrolic N significantly enhance the homolytic cleavage of H₂O₂, leading to selective and efficient generation of ^•OH, while graphitic N favors the less effective heterolytic cleavage pathway. Building on this finding, the active N species were precisely regulated by adjusting the pyrolysis temperature, resulting in the optimized NC-800 catalyst achieving 91.13% total organic carbon removal for extracting wastewater from spent lithium-ion battery recycling. Moreover, the activity of NC-800 was restored after simple thermal treatment, demonstrating excellent regeneration capability. This study sheds light on strengthening the pathways of NC catalysts through manipulating nitrogen species and provides an efficient approach for wastewater treatment.</p>","PeriodicalId":7008,"journal":{"name":"ACS ES&T engineering","volume":"4 12","pages":"3001–3009 3001–3009"},"PeriodicalIF":7.4,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142843231","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":"Pt-Nanoparticle-Loaded Porous SnO2 for Optimizing H2S-Sensing Performance at Room Temperature","authors":"Peijin Zou,&nbsp;Zhuangzhuang Ma,&nbsp;Zihuan Tang,&nbsp;Xiaotong Gao,&nbsp;Xiaoxiong Hou and Lichao Jia*,&nbsp;","doi":"10.1021/acsestengg.4c0052210.1021/acsestengg.4c00522","DOIUrl":"https://doi.org/10.1021/acsestengg.4c00522https://doi.org/10.1021/acsestengg.4c00522","url":null,"abstract":"<p >Achieving the real-time detection of hydrogen sulfide (H₂S) based on metal oxide semiconductor (MOS) gas sensors is of great significance for rapid disease diagnosis. However, the high-power consumption and poor selectivity severely limit its practice application. In this study, a platinum nanoparticle (Pt NPs)-loaded porous metal–organic framework (MOF)-derived SnO₂ material was successfully synthesized to optimize the H₂S-sensing performance at room temperature. The optimized Pt-loaded porous SnO₂-based gas sensor exhibited remarkably high sensitivity (712–10 ppm), fast response (21 s), good selectivity, and extremely low detection limit for H₂S (10 ppb) at room temperature. The in-depth analysis demonstrated that the porous structure of Sn-MOF can provide adequate active reaction sites for gas molecules. Moreover, the uniform distribution of surface-loaded Pt NPs can initiate electron and chemical sensitization effects, thereby improving the sensing performance. The successful application of Pt NPs provides a novel approach to improve the room-temperature (RT) sensing performance of metal-oxide-semiconductor-based gas sensors.</p>","PeriodicalId":7008,"journal":{"name":"ACS ES&T engineering","volume":"5 1","pages":"260–270 260–270"},"PeriodicalIF":7.4,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143091778","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":"Enhancing Food Waste Anaerobic Digestion Efficiency with Biochar as a Sustainable Technology in Decentralized Real-World Systems","authors":"Yong Wei Tiong,&nbsp;Hailin Tian,&nbsp;Pooja Sharma,&nbsp;Miao Yan,&nbsp;Heng Thong Lam,&nbsp;Jonathan Tian En Lee,&nbsp;Jingxin Zhang and Yen Wah Tong*,&nbsp;","doi":"10.1021/acsestengg.4c0057510.1021/acsestengg.4c00575","DOIUrl":"https://doi.org/10.1021/acsestengg.4c00575https://doi.org/10.1021/acsestengg.4c00575","url":null,"abstract":"<p >Long-term anaerobic digestion (AD) of food waste often faces challenges, with volatile fatty acid inhibition being a common issue that hinders optimal performance. This research explores the effect of biochar supplementation on long-term AD of food waste characterized by volatile fatty acid inhibition. The findings demonstrate that adding a modest amount of biochar (0.055 g/L) effectively enhances AD under ambient conditions at 29 °C. This biochar supplementation reduced volatile fatty acids to a safe level of 1195 mg/L after 36 days, well within the generally accepted safe threshold of 1500 mg/L. This safe threshold is supported by other studies, which indicate that maintaining VFA concentrations below 1500 mg/L minimizes the risk of process inhibition and ensures stable AD operation. Additionally, the normalized specific biogas yield averaged 1.33 ± 0.45 m³/kg VS, representing a 47.4% improvement over the control AD conducted under identical conditions. After stabilization, the study assessed whether AD could maintain functionality and stability under mesophilic conditions (35 °C) without further biochar supplementation, simulating a real-world scenario to test long-term efficacy in industrial-like conditions. This mesophilic postbiochar AD resulted in an additional 31.8% increase in the normalized average specific biogas yield, reaching 1.95 ± 0.25 m³/kg VS. Biochar increased <i>Methanosaeta</i> methanogens by 30%, enhancing direct interspecies electron transfer and strengthening syntrophic interactions. This shift made aceticlastic methanogens 9 times more prominent, improving acetate oxidation, biogas yield, and overall AD stability. These findings highlight biochar’s potential to enhance decentralized biogas facilities, promote sustainable food waste management, and advance the bioeconomy by providing a replicable model for closing the food waste loop.</p>","PeriodicalId":7008,"journal":{"name":"ACS ES&T engineering","volume":"5 2","pages":"500–514 500–514"},"PeriodicalIF":7.4,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143402100","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":"Phenomenological Interpretations of Membrane Properties Following Repeated Chemical Cleaning of an End-of-Life Potable Reuse Reverse Osmosis Element Dominated by Inorganic Fouling","authors":"Bilal Abada,&nbsp;Jana Safarik,&nbsp;Kenneth P. Ishida and Shankararaman Chellam*,&nbsp;","doi":"10.1021/acsestengg.4c0048610.1021/acsestengg.4c00486","DOIUrl":"https://doi.org/10.1021/acsestengg.4c00486https://doi.org/10.1021/acsestengg.4c00486","url":null,"abstract":"<p >A tail end-of-life reverse osmosis (RO) element from the third stage of a three-stage train extensively fouled by silicon was investigated for the effects of repeated alkaline cleaning and their consequences on foulant reversal and membrane integrity. Detailed surface characterization revealed that after four years of operation in the world’s largest potable reuse facility, it was severely fouled by inorganic substances with lesser contributions from bioorganic materials that together had reduced its water permeance and salt rejection to only ∼20 and ∼80% of their initial values, respectively. Swatches of the heavily fouled membrane were exposed repeatedly (but separately) to two high-pH cleaning agents (NaOH or TPP/DBS, a mixture of sodium tripolyphosphate and sodium dodecylbenzesulfonate) simulating repetitive cleaning-in-place (CIP) protocols typical of real-world operations. Although five-to-ten cleaning cycles fully recovered the fouled membrane’s water permeance, salt rejection always remained below 90% confirming its end-of-life. X-ray photoelectron (XPS), energy-dispersive X-ray (EDS), and Fourier transform infrared (FTIR) spectroscopy of fouled membranes implicated silicon as the dominant foulant, which was only partially removed even after ten cleaning cycles, although water permeance was completely restored. Importantly, exposing a virgin membrane to identical “cleaning” regimens as the end-of-life membrane artificially increased water permeance without changing its salt rejection. FTIR and XPS scans of the virgin membrane following repetitive exposure to NaOH or TPP/DBS revealed no damage/degradation of its polyamide layer as demonstrated by the relatively constant amide I/amide II absorbance ratios and consistent oxygen/nitrogen atomic ratios, both symptomatic of maintaining membrane integrity. Hence, we phenomenologically invoked swelling and/or surface property modifications to mechanistically explain the quantitative increase of water permeance after repeatedly exposing the virgin membrane to CIP agents (while maintaining the active polyamide layer’s integrity). Similarly, we attributed a portion of the restored permeance of the fouled membrane upon progressive chemical cleaning to swelling and/or surface property modification that could be indirectly inferred. Therefore, it is paramount to comparatively characterize virgin and fouled membranes prior to and after exposure to CIP chemicals to distinguish foulant removal from other mechanisms potentially contributing to recovering water permeance.</p>","PeriodicalId":7008,"journal":{"name":"ACS ES&T engineering","volume":"5 1","pages":"167–178 167–178"},"PeriodicalIF":7.4,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsestengg.4c00486","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143091803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"d-Phenylalanine Alleviates the Corrosion by Desulfovibrio vulgaris in Saline Water","authors":"Hongyi Li,&nbsp;Zhengyan Kang,&nbsp;Chengcheng Ding,&nbsp;Xinxin Zhao,&nbsp;Yiqi Cao,&nbsp;Baiyu Zhang,&nbsp;Chao Song* and Shuguang Wang*,&nbsp;","doi":"10.1021/acsestengg.4c0036210.1021/acsestengg.4c00362","DOIUrl":"https://doi.org/10.1021/acsestengg.4c00362https://doi.org/10.1021/acsestengg.4c00362","url":null,"abstract":"<p >A biofilm is a major contributor to microbiologically influenced corrosion (MIC) in cooling water systems, resulting in severe economical and environmental impacts. <span>d</span>-Amino acids offer a potential alternative for preventing biofilm formation in these systems, where salinity levels vary due to diverse water sources, such as freshwater and diluted seawater. However, the impact of <span>d</span>-amino acids on corrosion inhibition under saline conditions remains unexplored. In this study, we evaluated the effect of <span>d</span>-phenylalanine (<span>d</span>-Phe) on corrosion by <i>Desulfovibrio vulgaris</i> at three salinity levels. <span>d</span>-Phe (10 mg/L) played little role in corrosion inhibition at low salinity (5 g/L) but obviously decreased the corrosion by 40.6% and 59.6% at moderate salinity (15 g/L) and high salinity (20 g/L), respectively. It was attributed to that <span>d</span>-Phe reduced the secretion of extracellular protein from 292.5 μg/mg to 245.6 μg/mg and decreased the biofilm thickness from 25.46 μm to 20.87 μm on the coupon surface. Besides, <span>d</span>-Phe decreased the sessile cells from 15.1 × 10⁷ cells/cm² to 12.8 × 10⁷ cells/cm² at high salinity. Furthermore, transcriptome analysis found that indole, the signal molecule negatively regulating the biofilm formation, was increased by adding <span>d</span>-Phe at high salinity. Moreover, peptidoglycan reorganization was strengthened at high osmotic pressure via absorbing additional <span>d</span>-Phe, leading to weak bacterial adhesion. The work provides mechanistic insights into the application of <span>d</span>-Phe for biofilm inhibition and MIC mitigation in industries.</p>","PeriodicalId":7008,"journal":{"name":"ACS ES&T engineering","volume":"4 12","pages":"2938–2948 2938–2948"},"PeriodicalIF":7.4,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142850305","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":"Mechanism of Dissolved Organic Matter Constructing Zerovalent Iron Interfacial Mass-Transfer Channel Combined with Shewanella oneidensis MR-1 To Remove Cr(VI)","authors":"Minghui Xiang,&nbsp;Long Chen,&nbsp;Xinlei Ren,&nbsp;Zhiyuan Yang,&nbsp;Shiting Zhu,&nbsp;Ziying Zhang,&nbsp;Mengyu Su,&nbsp;Jin Zhang* and Hui Li*,&nbsp;","doi":"10.1021/acsestengg.4c0050610.1021/acsestengg.4c00506","DOIUrl":"https://doi.org/10.1021/acsestengg.4c00506https://doi.org/10.1021/acsestengg.4c00506","url":null,"abstract":"<p >Nanoscale zerovalent iron (nZVI) is a promising remediation agent for the removal of heavy-metal wastewater. However, nZVI tends to agglomerate and be oxidatively deactivated during the reaction, which limits its application. To address the problem, this study develops a novel modification method to regulate the reaction interface of nZVI by introducing fulvic acid (FA), a naturally occurring environmental component, to the synthesis of nZVI. FA disrupts the circumferential-stress equilibrium of nZVI, enhances the Kirkendall effect, and establishes mass-transfer channels, facilitating the outward transfer of reducible Fe(II) and electrons and the inward transport of surface-adsorbed Cr(VI). The Cr(VI) removal is further enhanced by coupling FA-nZVI with <i>Shewanella oneidensis</i> MR-1, which reduces Fe(III) hydroxides to Fe(II) at the FA-nZVI interface, thereby preventing accumulation of the passivation layer that blocks the mass-transfer channels. The synergistic action of mass-transfer channels with MR-1 enhances the Cr(VI) removal rate by 4.7 times, ensuring a Cr(VI) removal rate of more than 60% under extreme conditions. By exploring the new functions of FA as an organic carbon component, this study provides a fresh perspective on carbon utilization in ecosystems. Leveraging environmental factors for the microstructural modulation of nZVI is an efficient and environmentally friendly approach for remediation of heavy-metal pollution.</p>","PeriodicalId":7008,"journal":{"name":"ACS ES&T engineering","volume":"5 1","pages":"215–225 215–225"},"PeriodicalIF":7.4,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143091528","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":"Sodium Dodecylbenzenesulfonate Promotes Fe@Fe2O3 Electron Transfer and Induces Free-Radical Conversion to Enhance Tetrabromobisphenol A Degradation","authors":"Zhiyuan Yang,&nbsp;Yujing Huang,&nbsp;Hui Li,&nbsp;Jin Zhang* and Minghui Xiang*,&nbsp;","doi":"10.1021/acsestengg.4c0042310.1021/acsestengg.4c00423","DOIUrl":"https://doi.org/10.1021/acsestengg.4c00423https://doi.org/10.1021/acsestengg.4c00423","url":null,"abstract":"<p >The solubility of hydrophobic pollutants in the aqueous phase affects the degradation efficiency of the pollutants, and cosolvents are usually used to enhance the solubility of hydrophobic pollutants; however, the effect of cosolvents on the pollutant degradation process is not clear. This study constructed a sodium dodecylbenzenesulfonate (SDBS)/Fe@Fe₂O₃/PMS system for the efficient removal of tetrabromobisphenol A (TBBPA). SDBS increases the adsorption of oxygen species on the surface of Fe@Fe₂O₃, disrupts the dense oxide layer, and promotes the release of iron ions from the core. Kinetic results indicate that the degradation rate constant of TBBPA increases by 87.5 times in the presence of SDBS, and the system is minimally affected by environmental factors, making it broadly applicable. SDBS enhances the dissolved oxygen in the system, promotes the conversion of hydroxyl radicals (^•OH) into superoxide radical (O₂^•–) and singlet oxygen (¹O₂), and facilitates the transformation of TBBPA into TBBPA radical cations through electron transfer, which then undergoes debromination, hydroxylation, and demethylation to form small molecular degradation products. The dual role of SDBS enables the reutilization of aged ZVI, making it a promising technology for pollutant remediation.</p>","PeriodicalId":7008,"journal":{"name":"ACS ES&T engineering","volume":"5 1","pages":"12–21 12–21"},"PeriodicalIF":7.4,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143091080","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":"Sulfate Leached from Phosphogypsum Is Transformed in a Hydrogen-Based Membrane Biofilm Reactor","authors":"Anwar Alsanea,&nbsp;Ayoub Bounaga,&nbsp;Karim Lyamlouli,&nbsp;Youssef Zeroual,&nbsp;Rachid Boulif,&nbsp;Chen Zhou and Bruce Rittmann*,&nbsp;","doi":"10.1021/acsestengg.4c0056310.1021/acsestengg.4c00563","DOIUrl":"https://doi.org/10.1021/acsestengg.4c00563https://doi.org/10.1021/acsestengg.4c00563","url":null,"abstract":"<p >The high level of sulfate in phosphogypsum (PG), a byproduct of phosphoric acid production, offers an option of recovering elemental sulfur (S⁰). The first step is reducing sulfate to soluble sulfide, which can then be partially oxidized to S⁰. We evaluated sulfate reduction to soluble sulfide using a hydrogen-based membrane biofilm reactor (H₂-MBfR) from PG leachate (PG water). The H₂-MBfR was initiated using synthetic sulfate medium prior to switching to PG water, and it achieved sulfate removal of 70–80% and ∼60% of influent S as soluble sulfide. Upon switching to PG water, sulfate removal flux increased due to higher sulfate surface loading, but soluble sulfide kept declining and precipitates began forming. Venting the fibers to release accumulated CO₂ increased the H₂ availability and improved flux. Batch operation increased the generation of soluble sulfide, as sulfate was reduced biologically instead of precipitating as CaSO₄ (as verified by X-ray diffraction and solubility calculations). Alkalinity analyses quantified the effects of precipitation, mainly CaSO₄, on the sulfide reduction performance. While H₂-MBfR demonstrated promise for reducing sulfate to sulfide in PG water, its long-term success will require that calcium be minimized to reduce abiotic sulfate removal, while H₂ delivery must slightly exceed the H₂ demand for biological sulfate reduction to sulfide.</p>","PeriodicalId":7008,"journal":{"name":"ACS ES&T engineering","volume":"5 2","pages":"468–474 468–474"},"PeriodicalIF":7.4,"publicationDate":"2024-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsestengg.4c00563","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143402491","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}