Wastewater Research Articles

Removal of per- and polyfluoroalkyl substances (PFAS) from municipal wastewater by foam fractionation

Municipal wastewater has a relatively low content of per- and polyfluoroalkyl substances (PFAS), compared with other point sources such as landfill leachate and industrial effluents. Nevertheless, it is considered as one of the major point pollution sources. Foam fractionation was previously shown to effectively remove PFAS from different water matrices and to reach a high PFAS enrichment. In this study, the removal of PFAS from municipal wastewater of different origins was investigated. Despite the low foaming potential, it was possible to reach an average removal of the sum of perfluorooctanesulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), and perfluorohexanesulfonic acid (PFHxS) of 93 %, the removal of the sum of 21 PFAS of 56 %, and the removal of the sum of PFAS expressed as PFOA equivalents (ΣPFOAeq) of 91 %, without any surfactant addition utilizing a novel approach of foam collection. The PFAS content was reduced to below the limit values for drinking water in Sweden and the anticipated future limit values for surface water in the European Union. The addition of four commercial surfactants and an extract of extracellular polymeric substances (EPS) from waste activated sludge each enhanced the foam formation. Moreover, a cationic surfactant increased the removal of short-chain PFAS. Additionally, foam fractionation of activated sludge was performed. A considerably lower ΣPFOAeq removal of only 20 % was demonstrated, which was explained by a high proportion of PFAS sorbed to sludge. Finally, the study discusses the practical implications of the application of foam fractionation at municipal wastewater treatment plants.

Assessing human-source microbial contamination of stormwater in the U.S

Stormwater capture and use (SCU) projects have the potential to provide a significant portion of municipal water demand. However, uncertainty about the degree of microbial contamination in stormwater and the required treatment is a barrier for implementation of SCU projects. Stormwater runoff could become contaminated with human fecal matter in areas with deteriorating infrastructure where raw wastewater exfiltrates from sewer networks to stormwater collection networks, homeless encampments exist, or sanitary sewer overflows (SSOs) occur. Estimation of human fecal contamination can inform selection of stormwater treatment targets. This study investigates stormwater microbial contamination originating from human fecal matter using observed detections and concentrations of human microbial source tracking (MST) markers and potentially human-infectious pathogens (PHIPs). First, a systematic review complied measurements of human MST markers in wet and dry weather stormwater flows and influent wastewater. In addition, measurements of viral pathogens (e.g., adenoviruses, norovirus GI+GII, and enteroviruses) and protozoan pathogens (e.g., Giardia lamblia and Cryptosporidium parvum) in wet weather flows and influent wastewater were assessed. Human MST marker and PHIP data were statistically analyzed and applied to estimate a human fecal contamination analog (HFCA) which is an estimate of the amount of human fecal matter based on relative concentrations of microbial contaminants in stormwater compared to municipal wastewater. Human MST-based HFCAs in wet and dry weather flows ranged from <10−7.0 to 10−1.5 (median = 10−4.5) and 10−12 to 10−2.6 (median = 10−7.0), respectively. PHIP-based HFCAs in wet weather flows ranged from ∼10−8 to 10−0.14. Estimates of human MST-based HFCAs are more reliable than PHIP-based HFCAs because the current PHIP datasets are generally limited by the number of data points, percent detection, variability observed within the statistical distributions, and the geographical span of sampling locations. The use of human MST-based HFCAs is recommended to guide the selection of stormwater treatment process trains that are protective of public health based on the intended end use. Application of HFCA 10−1 (i.e., sewage dilution 10−1) remains a reasonable conservative estimate of human fecal contamination in stormwater to inform selection of pathogen log reduction targets based on the data presently available.

Bacterial hosts and horizontal transfer characteristics of clinically important tet(X)-variant genes in municipal wastewater treatment plants using epicPCR-directed cultivation strategy

Mobile tet(X)-variant genes confer resistance to a wide range of tetracyclines, including the antibiotic of last-resort, tigecycline, raising significant concerns regarding their potential spread cross-environmental dissemination. However, the bacterial hosts and environmental spread of these genes remain poorly understood. Herein, a retrospective study unveiled the prevalence of tet(X)-variant genes (ranging from tet(X3) to tet(X6)) in activated sludge samples from five municipal wastewater treatment plants (WWTPs) from 2013 to 2021. Among these variants, tet(X4) exhibited the highest detection frequency (100 %) and abundance [(2.48 ± 3.07) × 107 copies/g dry weight] with an increasing trend. An epicPCR-directed cultivation strategy was proposed to facilitate the targeted isolation of tet(X4)-carrying bacterial hosts in activated sludge. This strategy involves the identification of bacterial host profiles using epicPCR and subsequent selective isolating target bacteria. Enterobacteriaceae emerged as the primary bacterial host for tet(X4), alongside previously unreported genera like Providencia, Advenella, and Moheibacter. Subsequent selective isolation of the most abundant Enterobacteriaceae based on the epicPCR-informed host spectrum yielded 39 tet(X4)-carrying Escherichia coli strains from the WWTP. Whole genome sequencing of tet(X4)-positive strains revealed that plasmid-mediated horizontal gene transfer is the primary mechanism driving tet(X4) dissemination. Plasmids including IncFIA(HI1)/IncHI1A/IncHI1B(R27) and IncX1, commonly reported in various clinical and animal settings, were identified as the predominant carriers of tet(X4). E. coli strains harbouring tet(X4) in the WWTP showed substantial genetic similarity to strains from hospital and animal sources, underscoring concerns about the potential risk of across diverse sectors. This study provided the first glimpse of the presence of mobile tet(X)-variants in WWTPs, and highlighted the promise of the epicPCR-directed cultivation strategy for exploring bacterial hosts of clinically important ARGs in different habitats from a One Health perspective.

Feedstock-dependent antibiotic resistance gene patterns and expression profiles in industrial scale biogas plants revealed by meta-omics technology

This study investigated antimicrobial resistance in the anaerobic digesters of two industrial-scale biogas plants processing agricultural biomass and municipal wastewater sludge. A combination of deep sequencing and genome-centric workflow was implemented for metagenomic and metatranscriptomics data analysis to comprehensively examine potential antimicrobial resistance in microbial communities. Anaerobic microbes were found to harbour numerous antibiotic resistance genes (ARGs), with 58.85% of the metagenome-assembled genomes (MAGs) harbouring antibiotic resistance. A moderately positive correlation was observed between the abundance and expression of ARGs. ARGs were located primarily on bacterial chromosomes. A higher expression of resistance genes was observed on plasmids than on chromosomes. Risk index assessment suggests that most ARGs identified posed a significant risk to human health. However, potentially pathogenic bacteria showed lower ARG expression than non-pathogenic ones, indicating that anaerobic treatment is effective against pathogenic microbes. Resistomes at the gene category level were associated with various antibiotic resistance categories, including multidrug resistance, beta-lactams, glycopeptides, peptides, and macrolide-lincosamide-streptogramin (MLS). Differential expression analysis revealed specific genes associated with potential pathogenicity, emphasizing the importance of active gene expression in assessing the risks associated with ARGs.

Sustainability Strategies in Municipal Wastewater Treatment

The European Parliament adopted a legislative resolution of 10 April 2024 on the proposal for a directive of the European Parliament and of the Council concerning urban wastewater treatment. The reduction in pollution in discharged treated wastewater in the parameters of BOD5, total nitrogen, and total phosphorus was emphasized. Based on these results, it stated that the impacts on the quality of lakes, rivers, and seas in the EU are visible and tangible. At the same time, it was emphasized that the sector of urban wastewater removal and treatment is responsible for 0.8% of total electricity consumption and about 0.86% of all greenhouse gas emissions in the entire EU. Almost a third of these emissions could be prevented by improving the treatment process, better use of sewage sludge, and increasing energy efficiency, as well as a higher rate of use of renewable resource technologies. It is also necessary to integrate treatment processes into the circular economy. Sludge management and water reuse are suboptimal as too many valuable resources are still being wasted. This article focuses on sustainable municipal wastewater treatment, innovative and new wastewater treatment processes and technologies (combined and hybrid processes, ANAMMOX, etc.) and their use in practice with the aim of increasing environmental and energy efficiency and reducing the carbon footprint. The research is focused on the possibilities of increasing the efficiency of energy processing of sludge, reuse of nitrogen and phosphorus, sludge, and reuse of treated wastewater.

Anaerobic Co-Digestion of Coffee Processing Wastewater and Microalgal Biomass After Protein Extraction

Anaerobic Co-Digestion of Coffee Processing Wastewater and Microalgal Biomass After Protein Extraction

Enhanced nitrogen removal from secondary effluent of municipal wastewater using denitrification filter: Feasibility of refractory organics as a carbon source

Conventional advanced nitrogen removal in municipal wastewater is hindered by the limited availability of carbon sources in the secondary effluent. However, refractory organics present in it had the potential to serve as intrinsic carbon sources after hydrolysis for nitrogen removal via simultaneous denitrification and partial-denitrification anammox (PDA) processes. To assess this potential, a denitrification filter was set up in this study to evaluate its feasibility of concurrent processes. Results showed that increasing influent ammonium (NH4+-N) from 1.0 to 7.0 mg/L increased total nitrogen (TN) removal from 52.4 % to 89.9 %. Simultaneous occurrence of PDA and denitrification process were confirmed by the actual chemical oxygen demand (COD) consumption (0.8–1.2 mg/mg TN removal) from non-fluorescent organics. The presence of the anammox, hydrolytic and denitrifying bacteria further supported the achievement of nitrogen removal through PDA and denitrification processes by utilizing hydrolytic products biodegraded from refractory organics.

Fouling of Reverse Osmosis (RO) and Nanofiltration (NF) Membranes by Low Molecular Weight Organic Compounds (LMWOCs), Part 1: Fundamentals and Mechanism.

Reverse osmosis (RO) and nanofiltration (NF) are ubiquitous technologies in modern water treatment, finding applications across various sectors. However, the availability of high-quality water suitable for RO/NF feed is diminishing due to droughts caused by global warming, increasing demand, and water pollution. As concerns grow over the depletion of precious freshwater resources, a global movement is gaining momentum to utilize previously overlooked or challenging water sources, collectively known as "marginal water". Fouling is a serious concern when treating marginal water. In RO/NF, biofouling, organic and colloidal fouling, and scaling are particularly problematic. Of these, organic fouling, along with biofouling, has been considered difficult to manage. The major organic foulants studied are natural organic matter (NOM) for surface water and groundwater and effluent organic matter (EfOM) for municipal wastewater reuse. Polymeric substances such as sodium alginate, humic acid, and proteins have been used as model substances of EfOM. Fouling by low molecular weight organic compounds (LMWOCs) such as surfactants, phenolics, and plasticizers is known, but there have been few comprehensive reports. This review aims to shed light on fouling behavior by LMWOCs and its mechanism. LMWOC foulants reported so far are summarized, and the role of LMWOCs is also outlined for other polymeric membranes, e.g., UF, gas separation membranes, etc. Regarding the mechanism of fouling, it is explained that the fouling is caused by the strong interaction between LMWOC and the membrane, which causes the water permeation to be hindered by LMWOCs adsorbed on the membrane surface (surface fouling) and sorbed inside the membrane pores (internal fouling). Adsorption amounts and flow loss caused by the LMWOC fouling were well correlated with the octanol-water partition coefficient (log P). In part 2, countermeasures to solve this problem and applications using the LMWOCs will be outlined.

Modification of steel slag and its application for phosphate and ammonia removal in aquatic products processing wastewater

ABSTRACT This study aims to modify different types of steel slag by heating, characterise the material and test its ability for adsorption of phosphate and ammonia from aquatic products processing wastewater. The materials were characterised by SEM, EDS, BET and FT-IR analyses. The effects of the type of steel slag, calcination temperature in steel slag modification, pH, contact time, adsorbent mass and initial pollutant concentration were investigated using the one-factor-at-a-time approach. The results show that the adsorption kinetic of the samples followed the pseudo-second-order model, whereas their adsorption isotherm fitted well with the monomolecular adsorptive Langmuir with a maximum phosphate adsorption capacity of 45.045 mgPO43-/g. Optimisation using Response Surface Methodology was conducted with the independent factors (adsorbent doses, contact time and calcination temperature of steel slag) and response (removal efficiency of phosphate). The temperature and dosage of the material significantly affected phosphate removal efficiency and optimisation conditions were suggested. Validation of one optimum condition at the calcination temperature of 801°C, the adsorbent dosage of 11.9 g/L and the contact time of 72 min using real aquatic products processing wastewater resulted in the removal efficiencies of 86.93, 87.59, 7.76 and 7.58% for phosphate, total phosphorus, ammonia and total nitrogen, respectively.

Circular Economy in Morocco: Status and Perspectives and Policy Implications for Vietnam

This paper explores the current status of the circular economy (CE) in Morocco, its potential future directions, and policy implications for Vietnam. The concept of CE, which promotes sustainable resource use, waste reduction, and regeneration, is increasingly gaining global traction. Morocco, having made significant progress in sectors such as waste management, agriculture, renewable energy, and water resource management, serves as a valuable case study. Key initiatives like the National Solid Waste Management Program (PNDM) and the "Green Morocco Plan" highlight Morocco’s successful integration of CE principles. Despite challenges such as financial constraints and low public awareness, Morocco's transition to a circular economy presents numerous opportunities, including job creation and innovation. For Vietnam, which faces growing environmental and resource pressures, Morocco’s experience offers critical insights. By adopting CE principles in waste management, agriculture, renewable energy, and water management, Vietnam can move toward more sustainable development. The paper suggests specific policy recommendations, including fostering public-private partnerships, enhancing regulatory frameworks, and promoting green financing. The lessons drawn from Morocco’s journey can help Vietnam align its growth with environmental sustainability, positioning both countries as leaders in the global shift towards a circular economy.

Metal-organic framework self-cleaning membrane enhanced water purification based on collaborative separation and photocatalysis process

The existence of membrane contamination will not only affect the flux and rejection of the membrane, but also greatly reduce the service life of the membrane. Therefore, the coupling of photocatalytic Metal-organic frameworks (MOFs) with separation membrane to prepare catalytic self-cleaning membrane can effectively alleviate membrane pollution and maintain membrane flux and rejection. The challenge of photocatalytic self-cleaning membrane treatment of organic wastewater is how to ensure a stable catalyst load while maintaining a high membrane flux, rejection and cycle life. In this paper, the heterojunction photocatalyst NH2-MIL-125@MIL-88B constructed based on the MOF-on-MOF principle was supported on Polyethersulfone (PES) substrate membrane by vacuum filtration method. Then, polyacrylic acid (PAA) and chitosan (CTS) are adhered to the loading side through a co crosslinking reaction, introducing PAA@CTS layer. The PAA@CTS layer not only improves the load stability of the photocatalyst but also enhances the hydrophilicity of the self-cleaning membrane in collaboration with the photocatalyst. The construction of the self-cleaning membrane further increases its flux without affecting the rejection of the base membrane, breaking the tradeoff between permeability and rejection. The rejection of the best self-cleaning membrane was 96.6 %, and the flux was 58.4 L·m−2·h−1. In the treatment process of simulated antibiotic wastewater, the flux recovery rate (FRR) of M-2 is as high as 98 %, and the irreversible fouling ratio (Rir) is only 1 %, which proves its good antifouling properties and stability, and is expected to be used for efficient treatment of antibiotic wastewater.

Solids retention time (SRT) control in the co-treatment of leachate with domestic sewage in aerobic granular sludge systems: Impacts on system performance, operational stability, and bioresource production

This study investigates the co-treatment of leachate and domestic sewage in municipal wastewater treatment plants using aerobic granular sludge (AGS) systems, focusing on granule formation, system stability, and resource production in two units (R1 and R2). In R2, solids retention time (SRT) was controlled between 10 and 25 days, while R1 maintained approximately 9 days. The results show that low leachate proportions (5 %) did not affect system performance or stability. However, increasing the leachate to 10 % reduced the structural stability of extracellular polymeric substances (EPS), leading to a significant decrease in alginate-like exopolysaccharides (ALE) production in R1 (216 mgALE/gVSS) and R2 (125 mgALE/gVSS). Principal component analysis revealed that SRT was crucial for optimizing biopolymer synthesis. Furthermore, SRT control in R2 improved filamentous control, biomass retention, and total nitrogen removal. Thus, selective biomass discharge is essential for maintaining granule stability, enhancing treatment efficiency, and supporting resource production.

Effects of operational parameters on fuel gas production from DC-transferred arc plasma processing of sewage sludge

ABSTRACT In this work, a DC-transferred arc plasma reactor was used to investigate the influence of operating parameters on the process of gas production from sewage sludge treatment. By varying the operating temperature, feedstock feed rate and exhaust gas flow, the study aims to elucidate the physicochemical mechanisms during plasma treatment. The sewage sludge from the municipal wastewater treatment plant has an ash content of 40.5%, consisting mainly of Si, Al, Fe and Ca (>75%), and a complex organic fraction containing carbonyls, amines and amides. At a constant mass of feedstock (without feed rate), the gas produced by the plasma treatment was obtained with a maximum syngas fraction of 86% and a heating value of 10,000 kJ/m3, while the process operated at a constant sludge feed rate of 300 g/min increased the volumetric fraction of the syngas to 95% and the heating value to 12,000 kJ/m3.

Using syringe filtration after lab-scale adsorption processes potentially overestimates PFAS adsorption removal efficiency from non-conventional irrigation water.

The adsorption process, known for its cost-effectiveness and high efficiency, has been extensively investigated at the laboratory scale for removing per- and polyfluoroalkyl substances (PFAS) from non-conventional irrigation water. However, a syringe filtration step is commonly used when quantifying PFAS removal during this adsorption process, potentially leading to PFAS retention onto the filters and an overestimate of adsorption removal efficiency. Here, we assessed the retention of three prevalent PFAS (i.e., perfluorooctanoic acid [PFOA], perfluorooctane sulfonic acid [PFOS], and perfluorobutanoic acid [PFBA]) on six syringe filters. When filtering distilled deionized water spiked with 1µg/L and 100µg/L of each PFAS, we observed the highest and lowest PFAS recovery percentages by mixed cellulose ester (MCE) (0.20µm, 25mm; 97±11%, 101±4.8%) and polytetrafluoroethylene (0.45µm, 13mm; 61±37%, 80±28%), respectively. Under the initial concentration of 1µg/L and 100µg/L, PFOS had recovery percentages of 55±25% and 68±24%, significantly lower than 96±12% and 99±5% for PFOA and 95±8% and 97±4% for PFBA, highlighting the importance of PFAS functional groups. PFAS recovery percentage increased with filtration volume in the order of 80±28% (1mL)<85±21% (5mL)<90±18% (10mL). Using MCE to filter treated municipal wastewater spiked with 1µg/L and 100µg/L of each PFAS, we found recovery percentages>90% for all three PFAS. Our study underscores the significance of syringe filter selection and potential overestimate of PFAS removal efficacy by the lab-scale adsorption processes.

Double bioinspired of robust BaSO4/SnO2 membrane with anti-crude oil adhesion and remarkable emulsion separation

Pollution from oily waste water is a serious environmental problem worldwide, causing serious damage to the environment and human health. At the same time, emulsifiers also cause great difficulties in wastewater treatment. Although efforts have been made to develop many high performance emulsion separation membranes, it is difficult to have the ability to resist crude oil pollution in practical applications. The construction of superoleophobic micro/nano-scale lamellar structured membranes with the potential to efficiently separate oil/water emulsions was inspired by the oil-resistant properties of fish scales and the unique adhesion of mussels. Tin dioxide, polydopamine and hydrophilic barium sulphate have been modified on the surface of stainless steel mesh by in-situ hydrothermal and dip coating. The superhydrophilic stainless steel mesh was successfully prepared by using the adhesion of polydopamine. Using the excellent underwater hydration ability of tin dioxide and the hydroxyl group-rich hydrophilic barium sulfate, the modified membrane showed excellent resistance to crude oil pollution. The superhydrophilic membrane can continuously separate different types of oil-in-water emulsions with high separation efficiency (99.9 %) and excellent separation flux (900 L m−2 h−1), with no decrease in efficiency and flux after 10 emulsion separation cycles. In addition, the superhydrophilic membrane has excellent durability and stability, remaining super-oleophobic underwater to sand shock, sandpaper abrasion, high saline corrosion and UV ageing. The prepared stainless steel membrane not only provides a novel anti-fouling strategy, but its excellent stability also provides some new inspiration for the treatment of oil and water pollution in the future.

Evaluation of Integrated Anaerobic/Aerobic Conditions for Treating Dye-Rich Synthetic and Real Textile Wastewater Using a Soda Lake Derived Alkaliphilic Microbial Consortia

Textile industry wastewater (WW) has intense color, high chemical oxygen demand (COD), pH, and salinity, making it challenging for conventional treatment. Soda lakes, with high alkalinity and salinity, host diverse microbes capable of textile dye degradation. This study evaluated anaerobic/aerobic reactors using alkaliphilic microbial consortia from Lake Chitu, an Ethiopian soda lake, for treating synthetic and real textile WW. The experimental setup consisted of a first-stage anaerobic reactor followed by a second-stage aerobic reactor, operating continuously with a predetermined flow rate and hydraulic residence time. After evaluating synthetic WW, real textile WW was collected in two batches (rounds I and II). The treatment setup removed 99% of the dye color for synthetic WW, 98% for round I, and 96% for round II. COD removal was 87% for synthetic WW, 86% for round I, and 93.37% for round II. TKN removal reached 90% for synthetic WW, 91% for round I, and 96% for round II at a steady state. Residual COD and TKN values met the final effluent discharge standards. GC–MS and IR analyses revealed that dyes were broken down into intermediate organic compounds under anaerobic conditions and further degraded into smaller molecules under aerobic conditions. This integrated reactor approach effectively removes dyes and enhances COD and TKN removal. The study’s novelty lies in evaluating both synthetic and real textile WW using integrated reactors under alkaline conditions in a continuous process, inoculating alkaliphilic consortia, without pre-enrichment or external nutrient addition to real WW. The study provides insights into the effectiveness of alkaliphilic microbial consortia derived from soda lakes for treating textile WW using integrated reactor conditions. Reactor microbiome characterization is needed to further explore microbial diversity and community structure.

Biochar for wastewater treatment: Addressing contaminants and enhancing sustainability: Challenges and solutions

In recent years, biochar has gained interest for its potential use in treating and removing contaminants from domestic, municipal, and industrial wastewater. When applied in fixed filter columns (BFCs), biochar can effectively immobilize, filter, and recover contaminants with high treatment efficiency. On average, COD removal is 80 %, nutrient removal is 71 % for nitrogen-ammonium and 57 % for phosphorus-phosphate, and pathogen reduction averages 2.4 log10 units. These results vary depending on factors such as the biochar's surface area, the conditions under which it was pyrolyzed, and operational parameters like hydraulic loading and retention time. Biochar addresses limitations in traditional wastewater treatment by leveraging adsorption, ion exchange, and biological degradation mechanisms. The larger surface area and functionalized surface of engineered biochar make it particularly effective in treating diverse pollutants, including heavy metals, nutrients, and emerging contaminants, such as antibiotic-resistant bacteria. As the global population and industrial activities increase, there is a pressing need for sustainable wastewater treatment technologies. Biochar addresses this need and serves as a waste valorization tool, contributing to bioenergy production, soil improvement, and other applications. The present review focuses on improving biochar's performance and durability in real-world applications by addressing challenges like physical degradation. It also proposes strategies to enhance biochar's properties and reuse potential.

Direct Electrolysis of Municipal Reclaimed Water for Efficient Hydrogen Production Using a Bifunctional Non-Noble-Metal Catalyst.

Water electrolysis for green H2 production traditionally requires a stable supply of renewable electricity and pure water. However, spatial separation of renewables and water resources as well as water scarcity per capita in China necessitate unconventional water resources for electrolysis. Reclaimed water produced from municipal wastewater treatment plants is widely distributed with quality improved significantly in recent years, which may be a promising alternative to feedstock. However, there are few reports on the direct use of this wastewater for H2 production. Here, we present a direct electrolysis of reclaimed water for decentralized H2 production by developing a highly efficient and stable bifunctional 3D-dandelion-like (DL) vanadium(V)-doped CoP catalyst grown in situ on Ni foam (NF) in an alkaline electrolyzer. The V-CoP-DL/NF electrode decreases 6.5 and 25% overpotentials of the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), respectively, compared to noble-metal Pt (HER) and IrO2 (OER) catalysts, and exhibits exceptional durability, as a voltage required for overall reclaimed water splitting only increases by 80 mV (1.81-1.89 V) after 90 days of operation at a current density of 10 mA cm-2. The maximum stable current can reach 1000 mA cm-2. The impacts of potential pollutants in reclaimed water on the performance of electrolysis and the behavior of major wastewater ions in alkaline electrolyte were investigated. The observed exceptional performance is attributed to the catalyst's unique nanostructure, which enhances charge transfer and reactant/electrolyte diffusion. The in situ growth strategy further enhances the conductivity and stability of the catalyst. This work underscores the feasibility of utilizing reclaimed water instead of pure water as the feedstock for sustainable hydrogen production.

Advances in bimetallic metal organic frameworks (BMOFs) based photocatalytic materials for energy production and waste water treatment

Advances in bimetallic metal organic frameworks (BMOFs) based photocatalytic materials for energy production and waste water treatment

The potential of alkaline tolerant microbial consortia for textile wastewater treatment under integrated anaerobic/aerobic conditions: Performance evaluation and microbial community analysis

Sequential anaerobic/aerobic (A/O) treatment conditions for textile wastewater (WW) are more effective than conventional biological treatment. Anaerobic treatment is essential because anaerobic microbes can first break down complex and recalcitrant compounds, which are difficult to degrade under aerobic conditions. The simpler, more degradable compounds are then further broken down by aerobic microbes. This study aimed to evaluate the performance of a sequential A/O treatment process using a pilot-scale reactor to treat real textile WW and to characterize reactor and inoculum microbial community structures. The reactors were inoculated with microbial consortia originating from a diverse alkaliphilic soda lake in the Ethiopian Rift Valley. The WW test parameters were used to evaluate the performance of the treatment process. At steady state, the removal efficiencies were 97 % for dye, 86 % for Chemical Oxygen Demand (COD), and 93 % for Total Kjeldahl Nitrogen (TKN). Amplicon sequencing revealed that Firmicutes, Proteobacteria, and Actinobacteria were the dominant phyla in all the samples. Uncategorized microorganisms, followed by Alkalibacterium, Bifidobacterium, and Clostridium were the most abundant taxon in all the samples. The microbial community detected during the treatment process was not abundant in the inoculum originating from Lake Chitu, suggesting that the communities likely originated from textile WW. The textile WW treated with the integrated A/O process effectively degraded dyes, and the inoculated microbes demonstrated resistance to the toxic chemical composition of the WW. The integrated treatment process, along with the alkaliphilic microbial consortia, has proven to be practical for treating textile WW, offering valuable insights for field-scale applications.