Advanced Treatment Technologies Research Articles

Application of the sulfur-siderite composite filler: A case study of augmented performance and synergistic mechanism for low C/N wastewater treatment in constructed wetland

The urgent need to achieve sustainable development goals and address global climate change calls for innovative solutions in advanced low-carbon water treatment technologies. In this study, constructed wetlands (CWs), a sustainable and multifunctional wastewater treatment technology known for its low cost and energy efficiency, was focused. It was presented a novel approach that employs a sulfur-siderite composite filler in the constructed wetland (SSCF-CW), which demonstrated remarkable removal efficiencies for total phosphorus (TP) ranging from 81.14 % to 98.87 %, nitrate nitrogen (NO3−-N) ranging from 85.23 % to 99.82 %, and total nitrogen (TN) ranging from 91.65 % to 97.01 % in low C/N wastewater treatment. The electron resupply mode of the sulfur and iron cycles plays a pivotal role in enhancing denitrification efficiency. Furthermore, SSCF enhances the resilience of SSCF-CW against shock loadings, providing increased stability and performance with TN removal rate of 2.96 ∼ 3.42 g N·m−3·d−1 while HRT decreased from 48 h to 10 h. Notably, the majority of NO3−-N elimination occurs within the SSCF layer, where Thiobacillus species dominate the denitrification process in SSCF-CW. The introduction of SSCF promotes carbon fixation with the higher relative abundance of DLD gene (5.52 %) in SSCF-CW, benefiting microbial growth and accelerating electron transfer process. Co-precipitation and adsorption pathways in the SSCF layer primarily contribute to TP removal, while iron leaching from SSCF facilitates the formation of iron plaque on roots, establishing an iron reservoir and ensuring bioavailability. These findings highlight the significant potential of SSCF in constructed wetland systems, offering a cost-effective and sustainable low-carbon technology for municipal wastewater treatment.

Metagenomics insights into the performance and mechanism of soil infiltration systems on removing antibiotic resistance genes in rural sewage

The removal of antibiotic resistance genes (ARGs) in sewage is of great concern, but advanced sewage treatment technologies are not suitable for rural areas, so the multi-layer soil infiltration system (MSL) has been developed for rural sewage treatment. However, little is known about the performance and function of MSL in the treatment of ARGs in rural sewage. Here, we optimized the matrix composition and structure of MSL and explored the efficacy and mechanism of MSL systems for ARG removal under different hydraulic conditions. The ARGs removal rate of MSL ranged from 41.51% to 99.67%, in which MSL with the middle hydraulic load, high pollution load, and continuous inflowing conditions showed the best removal performance. In addition, this system can operate stably and resist the temperature fluctuation, which showed an equivalent removal rate of ARGs in warm and cold seasons, amounting to 69.0%. The structural equation model revealed that microorganisms in sewage could significantly affect ARG removal (path coefficient = 0.91), probably owing to their interspecies competition. As for the internal system, the reduction of ARGs was mainly driven by microorganisms in the system matrix (path coefficient = 0.685), especially soil-mixture-block (SMB) microorganisms. The physicochemical factors of the matrix indirectly reduce ARGs by affecting the microorganisms that adhere to the matrices. Note that the pairwise alignment of nucleotide analysis demonstrated that the system matrix, especially biochar in the SMB, adsorbed ARGs and their hosts from the sewage, and in turn eliminated them by inhibiting the spread and colonization of hosts, thereby reducing the abundance of ARGs. Collectively, this study provides a deeper insight into the removal of ARGs from rural sewage by MSL, which can help improve sewage treatment technologies.

Cerium added corn-based biochar as particle electrode for electrochemical oxidation industrial wastewater

ABSTRACT Three-dimensional (3D) electrochemical oxidation has become a popular advanced oxidation technology for wastewater treatment due to its various benefits. In this study, cerium (Ce) loaded biochar (Ce/BC) was used as a particle electrode to conduct the degradation of industrial wastewater released by the chemical industry. SEM, EDS, XRD, FTIR, XPS, and BET were used to characterize the properties of Ce/BC. The effects of some variables, including Ce loading (0–5%), pH (5–9), Ce/BC dosage (12.5–50.0 g/L), and working voltage (12–20 V), were evaluated with regard to COD elimination. The kinetics of COD oxidation and the energy consumption were carefully investigated. Tert-butanol significantly reduced the removal efficiency of COD, indicating that hydroxyl radicals generated during the process rather than direct electro-oxidation were the main mechanism for COD degradation. The treatment of industrial wastewater might benefit from the use of Ce/BC as particle electrode.

Is constructed wetlands carbon source or carbon sink? Case analysis based on life cycle carbon emission accounting

Constructed wetlands (CWs) are widely used to polish the effluent of wastewater treatment plants and micro-polluted river or lake water. However, the impact of large-scale applications of CWs on carbon emissions is unclear. In this study, the carbon footprints of two full-scale hybrid CWs were determined based on life cycle assessment (LCA). Results showed that the carbon emission of CW ranged from 0.10 to 0.14 kg CO2-eq/m3, and was significantly correlated with the influent chemical oxygen demand loads and electricity consumption. However, CW would approach carbon neutrality during the service period when taking plant carbon sequestration into consideration. Compared with other advanced wastewater treatment technologies, CWs showed significant low-carbon emission and cost-effective benefits. This study clarified the role of CWs in the carbon cycle and would provide guidance for the construction and management of CWs.

Insights into Mn loaded carbon-silica-membrane based catalytic ozonation process for efficient wastewater treatment: Performance and mechanism

Heterogeneous catalytic ozonation (HCO) is a promising technology for advanced wastewater treatment, and developing catalysts with both high catalytic activity and easy recycling capability is challenging but essential. In this work, easily separable Mn loaded carbon–silica-membrane (Mn-CSM) was synthesized by electrospinning and Mn-CSM based packed bed reactor was constructed for catalytic ozonation, achieving excellent catalytic performance for refractory organic degradation. Mn-CSM exhibited a lamellar structure with a thickness of several hundred micrometers and was centimeter-sized in the other two dimensions, which make it easy to be separated in wastewater treatment. At the microscopic scale, Mn-CSM was composed of highly connected nanofibers, which provided large specific surface area for the exposure of active sites. In oxalic acid (OA) degradation and coal gasification wastewater advanced treatment, Mn-CSM demonstrated superior catalytic ozonation performance. After 60 min, 93% of OA was degraded in Mn-CSM based HCO process, and the effluent COD of coal gasification wastewater decreased from 105 mg L−1 to 42 mg L−1. Reactive oxygen species in aqueous solution and on catalyst surface contributed to the organic degradation. The introduction of SiO2 nanoparticles in Mn-CSM can not only enhance its catalytic stability, but also improve fluid flow field distribution. Furthermore, the presence of SiO2 increased the hydrophilicity of Mn-CSM and a better removal of hydrophilic substances (HIS) was achieved in Mn-CSM based HCO. This study highlights a Mn-CSM ozone catalyst with high catalytic activity and easy recycling capability and a Mn-CSM based catalytic ozonation process, which is promising for the degradation of refractory organics in wastewater.

Hierarchical porous biochar for persulfate activation: Non-radical pathway for rapid degradation of organic pollutants

The development of efficient, low-cost, and environmentally friendly catalysts has the potential to significantly enhance the persulfate-based advanced oxidation technology for wastewater treatment. In this study, chitosan gel was ultilized as the biomass to be pyrolyzed by two-step pyrolysis method at 600 °C and 800 °C to produce biochar (BC-800). Results from the SEM, TEM, BET, Raman, and XPS characterizations showed that the BC-800 had a surface area of 1748 m2/g and a hierarchical pore structure with co-existing macropores, mesopores, and micropores, as well as an obvious graphitic carbon, pyridinic N, and graphitic N configurations. The prepared biochar was found to activate persulfate (PS) for rapid degradation of 2,4-dichlorophenol, with 90% of pollutants removed in 5 min due to the excellent mass transfer facilitated by the abundant pores. Chemical quenching experiments, EPR detection, and electrochemical analysis indicated that the degradation process was triggered by a nonradical pathway, in which the biochar acted as an electron transfer shuttle between the oxidant and pollutant. This electron transfer mechanism not only enabled the degradation system have a wide pH range for application, but it also demonstrated high resistance to inorganic anions in the aquatic environment. This research is expected to enhance the preparation method of hierarchical porous biochar and provide effective technical support for the biochar-activated PS for water purification.

Stereotactic Body Radiation Therapy: A Radiosurgery Society Guide to the Treatment of Localized Prostate Cancer Illustrated by Challenging Cases

Traditionally, external beam radiotherapy (EBRT) for localized prostate cancer (PCa) involved lengthy courses with low daily doses. However, advancements in radiation delivery and a better understanding of prostate radiobiology have enabled the development of shorter courses of EBRT. Ultrahypofractionated radiotherapy, administering doses greater than 5 Gy per fraction, is now considered a standard of care regimen for localized PCa, particularly for intermediate-risk disease. Stereotactic body radiotherapy (SBRT), a specific type of ultrahypofractionated radiotherapy employing advanced planning, imaging, and treatment technology to deliver in five or fewer fractions, is gaining prominence as a cost-effective, convenient, and safe alternative to longer radiotherapy courses. It is crucial to address practical considerations related to patient selection, fractionation scheme, target delineation, and planning objectives. This is especially important in challenging clinical situations where clear evidence for guidance may be lacking. The Radiosurgery Society endorses this case-based guide with the aim of providing a practical framework for delivering SBRT to the intact prostate, exemplified by two case studies. The article will explore common SBRT dose/fractionation schemes and dose constraints for organs-at-risk. Additionally, it will review existing evidence and expert opinions on topics such as SBRT dose escalation, the use of rectal spacers, the role of androgen deprivation therapy in the context of SBRT, SBRT in special patient populations (e.g., high-risk disease, large prostate, high baseline urinary symptom burdens, and inflammatory bowel disease), as well as new imaging-guidance techniques like Magnetic Resonance Imaging for SBRT delivery.

A review on triclosan in wastewater: Mechanism of action, resistance phenomenon, environmental risks, and sustainable removal techniques.

Triclosan, belonging to the bisphenols, is a known antiseptic broad-spectrum biocide. It has a very wide range of applications, both in health care and in the household. Triclosan enters the environment, both water bodies and soil, because of its high prevalence and the ability to accumulation. Excessive use of antimicrobial formulations may cause the generation of resistance among microorganisms. Reduced susceptibility to triclosan is observed more frequently and in an expanded group of microorganisms and is conditioned by a number of different mechanisms occurring on the molecular level. Conventional wastewater treatment processes are not always able to provide a reliable barrier to triclosan. Therefore, additional advanced treatment technologies are being considered in areas, where a triclosan contamination problem has been identified. Removal of triclosan from wastewater is carried out using different biological and chemical techniques; however, it should be pointed out that physico-chemical methods often generate toxic by-products. Toxicity of triclosan and its degradation products, bacterial resistance to this compound, and evident problems with triclosan elimination from wastewater are currently the main problems faced by companies creating products containing triclosan. PRACTITIONER POINTS: Triclosan is an emerging pollutant in the environment because of its ability to accumulation and high prevalence. Reduced susceptibility to triclosan is being observed more frequently. Conventional wastewater treatment processes are not always able to provide a reliable barrier to triclosan. Additional advanced treatment technologies should be implemented to remove triclosan from wastewater.

Unlocking the Potential of Nanobubbles: Achieving Exceptional Gas Efficiency in Electrogeneration of Hydrogen Peroxide.

The electrogeneration of hydrogen peroxide (H2 O2 ) via the oxygen reduction reaction is a crucial process for advanced water treatment technologies. While significant effort is being devoted to developing highly reactive materials, gas provision systems used in these processes are receiving less attention. Here, using oxygen nanobubbles to improve the gas efficiency of the electrogeneration of H2 O2 is proposed. Aeration with nanobubbles is compared to aeration with macrobubbles under an identical experimental set-up, with nanobubbles showing a much higher gas-liquid volumetric mass transfer coefficient (KL a) of 2.6 × 10-2 min-1 compared to 2.7 × 10-4 min-1 for macrobubbles. Consequently, nanobubbles exhibit a much higher gas efficiency using 60% of O2 delivered to the system compared to 0.19% for macrobubbles. Further, it is observed that the electrogeneration of H2 O2 using carbon felt electrodes is enhanced using nanobubbles. Under the same dissolved oxygen levels, nanobubbles boost the reaction yield to 84%, while macrobubbles yield only 53.8%. To the authors' knowledge, this is the first study to investigate the use of nanobubbles in electrochemical reactions and demonstrate their ability to enhance gas efficiency and electrocatalytic response. These findings have important implications for developing more efficient chemical and electrochemical processes operating under gas-starving systems.

Flue gas Pb0 removal from sludge incineration through biological lead oxidation coupled denitrification

Lead (Pb0) in flue gas from sludge incineration can seriously harm human health especially lead poisoning and blood lead increase. Microbial lead (Pb0) oxidation associated with nitrate reduction might be poorly understood in eliminating Pb0 pollution in flue gas from sludge incineration. In this study, a denitrifying bioreactor (DBR) was investigated for Pb0 removal from flue gas. Pb0 removal efficiency achieved 87% in 60-day operation. Dominated Pb0-oxidating-denitrifying bacteria such as Azoarcus, Thauera and Stappia could realize bacterial Pb0 oxidation and nitrate reduction through the regulation of lead oxidation genes (katE, K07217, aoxA, aoxB, moxA) and denitrification gene (napAB and narHGI). The up-regulation of amino acids and polysaccharide biosynthesis, transporters and phosphatase-relevant genes provided evidence of their involvement in the transformation of lead. The bio-oxidation of Pb0 adsorbed on EPS was coupled with denitrification, where Pb0 and nitrate served as the electron donor and terminal electron acceptor, respectively, and thereby formed redox between Pb0 and nitrate. Pb2+ oxidized from Pb0 was intracellularly accumulated, and complexed with EPS by binding with –OH and P = O. Pb0-containing flue gas was bio-stabilized in the form of Pb5(PO4)3Cl and protein/polysaccharide-Pb2+. Pb0 in flue gas was adsorbed by denitrifying bacteria, oxidized to Pb2+ coupling with denitrification, and biostabilized to achieve the removal of Pb0 from flue gas. These results show that the DBR advanced treatmenttechnology is achievable and provide new possibilities for applying the denitrifying bioreactor to remove heavy metals from flue gas.

Improvement of Machine Learning-Based Prediction of Pedicle Screw Stability in Laser Resonance Frequency Analysis via Data Augmentation from Micro-CT Images

To prevent pedicle screw implant failure, a diagnostic technique that allows surgeons to evaluate implant stability easily, quickly, and quantitatively in clinical orthopedic situations is required. This study aimed to predict the insertion torque equivalent to laboratory-level evaluation accuracy. This serves as an index of the implant stability of pedicle screws placed in cadaveric bone, which relies on laser resonance frequency analyses (L-RFA) when irradiating with two types of lasers. The machine learning analysis was optimized using a dataset with artificial bone as teaching data. In this analysis, many explanatory variables extracted from the laser-induced vibration spectra obtained during an analysis/RFA evaluation were predicted by selecting important variables using the least absolute shrinkage and selection operator and performing a non-linear approximation using support vector regression. It was found that combining both artificial and cadaveric bone data with the bone densities as teaching data dramatically improved the determination coefficient from R2 = −0.144 to R2 = 0.858 as the prediction accuracy and reduced the influence of differences between artificial and cadaveric bones. This technology will contribute to the development of preventive diagnostic technologies that can be used during surgery, which is necessary in order to further advance treatment technologies.

A comparative study using insulin pump therapy and continuous glucose monitoring in newly diagnosed very young children with type 1 diabetes: it is possible to bend the curve of HbA1c.

The target of metabolic control (HbA1c < 7% or 53mmol/mol) recommended by the ADA and ISPAD is attained by 30% of children with Type 1 Diabetes (T1D). Advances in technologies for T1D aim to improve metabolic outcomes and reduce complications. This observational study assesses the long-term outcomes of advanced technologies for treatment of T1D compared to conventional approach started at onset in a group of very young children with T1D. 54 patients with less 4years old at onset of T1D were enrolled and followed for up to 9years after diagnosis. 24 subjects started continuous subcutaneous insulin (CSII) treatment and 30 subjects received MDI therapy from onset. Auxological data, HbA1c and total daily insulin dose (TDD/kg) have been collected at admission and every 4months. HbA1cAUC>6%, rates of acute complications, glycemic variability indices and glucometrics were also recorded. Patients with CSII therapy had significantly lower mean HbA1c values compared to subjects receiving MDI treatment. CSII approach also recorded lower mean HbA1cAUC>6% and TDD/kg than MDI therapy. At the last download data, the time in range (TIR) was higher in patients with CSII and hyperglycemia events were lower. Better glycemic variability indices have been described during CSII therapy, including mean glycemia, standard deviation, coefficient of variation (CV), glycemia risk index (GRI) and high blood glucose index (HBGI). There was no statistically significant difference between frequency of severe hypoglycemia and ketoacidosis episodes between groups. Early initiation of diabetes technologies is safe and able to determine a better long term glycemic control in young children with T1D. It also allows to flatten the trajectory of HbA1c, probably reducing microvascular, macrovascular and neurological complications of diabetes in this very peculiar age group.

Magnetically recyclable TiO2/MXene/MnFe2O4 photocatalyst for enhanced peroxymonosulphate-assisted photocatalytic degradation of carbamazepine and ibuprofen under simulated solar light

In this study, a novel TiO2/Ti3C2/MnFe2O4 magnetic photocatalyst with dual properties, enabling (i) improved photocatalytic degradation with PMS activation under simulated solar light and (ii) magnetic separation after the degradation process in an external magnetic field was developed and applied for the efficient photodegradation pharmaceutically active compounds (PhACs) frequently present in wastewater and surface waters worldwide. MXene was used as a Ti precursor for anatase/rutile synthesis and as a co-catalyst in the photodegradation process. Manganese ferrite with ferrimagnetic properties was coupled with the TiO2/Ti3C2 composite to facilitate the magnetic separation after the purification process in an external magnetic field. Moreover, MnFe2O4 was used for PMS activation, producing •SO4- radicals with a strong oxidation ability and higher redox potential of 2.5–3.1 V (vs. NHE) than •OH radicals with a standard oxidation–reduction potential of 2.8 V. The effect of the manganese ferrite content in the composite structure (5 wt% and 20 wt%) on the physicochemical properties and photocatalytic activity of the magnetic photocatalyst was investigated. Furthermore, the most photocatalytic active composite of TiO2/MXene/5%MnFe2O4 was used for peroxymonosulphate-assisted photocatalytic degradation of ibuprofen and carbamazepine. The effect of peroxymonosulphate concentration (0.0625 mM, 0.125 mM, and 0.25 mM) and the synergistic effect of PMS activation on photocatalytic degradation was studied. Based on the obtained results, it was found that TiO2/MXene/5%MnFe2O4/PMS process is an efficient advanced treatment technology for the oxidation of emerging contaminants that are not susceptible to biodegradation. Carbamazepine and ibuprofen were completely degraded within 20 min and 10 min of the PMS-assisted photodegradation process under simulated solar light. The trapping experiments confirmed that •SO4- and •O2- are the main oxidising species involved in the CBZ degradation, while •SO4- and h+ in the IBP degradation. Furthermore, introducing interfering ions of Na+, Ca2+, Mg2+, Cl-, and SO42– in the model seawater did not affect the removal efficiency of both pharmaceuticals. In terms of reusability, the performance of the TiO2/MXene/5%MnFe2O4/PMS photocatalyst was stable after four subsequent cycles of carbamazepine and ibuprofen degradation.

Pharmaceutical residues in the ecosystem: Antibiotic resistance, health impacts, and removal techniques

Hospital wastewater has emerged as a major category of environmental pollutants over the past two decades, but its prevalence in freshwater is less well documented than other types of contaminants. Due to compound complexity and improper operations, conventional treatment is unable to remove pharmaceuticals from hospital wastewater. Advanced treatment technologies may eliminate pharmaceuticals, but there are still concerns about cost and energy use. There should be a legal and regulatory framework in place to control the flow of hospital wastewater. Here, we review the latest scientific knowledge regarding effective pharmaceutical cleanup strategies and treatment procedures to achieve that goal. Successful treatment techniques are also highlighted, such as pre-treatment or on-site facilities that control hospital wastewater where it is used in hospitals. Due to the prioritization, the regulatory agencies will be able to assess and monitor the concentration of pharmaceutical residues in groundwater, surface water, and drinking water. Based on the data obtained, the conventional WWTPs remove 10–60% of pharmaceutical residues. However, most PhACs are eliminated during the secondary or advanced therapy stages, and an overall elimination rate higher than 90% can be achieved. This review also highlights and compares the suitability of currently used treatment technologies and identifies the merits and demerits of each technology to upgrade the system to tackle future challenges. For this reason, pharmaceutical compound rankings in regulatory agencies should be the subject of prospective studies.

Development of a new CoS-Supported ZnAl2O4 catalyst for the visible photodegradation of a basic textile dye from water

The material is proven competitive for the solar treatment of wastewater from the textile industry -an essential source of water pollution worldwide. The system was prepared following a two-step hydrothermal method, showing photon absorption properties across the solar spectrum's UV and visible light regions. The main responsible species driving the photocatalytic process are proposed based on degradation experiments using appropriate scavengers. Further studies include consideration of operational parameters and cycling experiments to evaluate the stability of the catalyst. The results showed complete degradation (100%) based on dye bleaching and >90% mineralization of the dye based on total organic carbon analysis using dye concentrations of 20 ppm and catalyst loading of 1 g/l. Our findings point to sulfide-supported spinel materials as promising candidates for advanced solar oxidation technologies for wastewater treatment.

Enhanced conversion of superoxide radical to singlet oxygen in peroxymonosulfate activation by metal-organic frameworks derived heteroatoms dual-doped porous carbon catalyst

The activation of persulfate technology using carbon-based materials doped with heteroatoms has been extensively researched for the elimination of refractory pollutants in wastewater. In this study, metal-organic frameworks were utilized as precursors to synthesize P, N dual-doped carbon material (PNC), which was employed to activate peroxymonosulfate (PMS) for the degradation of tetracycline hydrochloride (TCH). The results demonstrated a 90.2% removal efficiency of total organic carbon within 60 min. The significant increase of surface defects on the nitrogen self-doped porous carbon materials anchored with phosphorus promoted the conversion of superoxide radical to singlet oxygen during PMS activation, which was identified as the key active species of PNC/PMS system. Additionally, the enhanced direct electron transfer also facilitated the degradation of TCH. Consequently, TCH was successfully degraded into nontoxic and harmless inorganic small molecules. The findings of this research provide valuable insights into improving the performance of heteroatom-doped carbon materials for pollutant degradation by activating PMS and transforming the non-radical pathway. The results highlight the potential of metal-organic frameworks derived heteroatoms dual-doped porous carbon catalysts for the development of advanced treatment technologies in wastewater treatment.

Effects of liquor production wastewater discharge on water quality and health risks in the Chishui River Basin, Southwest China

Learning whether the discharge of large amounts of liquor production wastewater in China affects water quality is crucial to maintaining sustainable economic development, especially in the vulnerable eco-environment of the karst area. The present study investigated the relationship between liquor production wastewater and water quality in the Chishui River Basin for the first time and proposes several constructive suggestions. After river remediation, water quality in spring, summer, autumn, and winter in the Chishui River Basin was found to be at an excellent level, with water quality in winter being the best. Worse water quality and higher health risks were found in liquor production areas (Guling County and Renhuai City) in comparison with other areas. The developed structural equation model showed that physicochemical indexes (especially in N and P) have a higher influence on water quality in comparison with the algae community, heavy metals, and environmental factors. Because liquor being a pillar industry in the locality and these factories discharging an enormous amount of wastewater every year, our results show that liquor production wastewater have affected the water quality to some extent in the Guling County and Renhuai City sections of the Chishui River Basin, and fortunately, the health risks were acceptable in 2020. To prevent potential risks, we suggest that a related department should apply a stricter standard to wastewater discharge. Furthermore, law-enforcement departments can encourage enterprises to develop or introduce more advanced water treatment technologies to achieve as much pollution-free discharge as possible. Our other suggestion is to develop a project to cleanly produce mineral water in high-quality water-resource areas along the Chishui River Basin, contributing to the sustainable growth of the shoreside economy.

Application of conventional and emerging low-cost adsorbents as sustainable materials for removal of contaminants from water.

The impact of water pollution has led to the search for cost-effective and environmentally friendly treatment processes to alleviate the associated environmental hazards. Adsorption is identified as an advanced treatment technology that offers simplicity and cheap alternatives to water treatment technologies when low-cost adsorbents such as industrial by-products, waste, and agricultural waste are utilized. The utilization of these materials as low-cost adsorbents for the treatment of drinking water will bring them some value. Several practices have been done to improve the removal efficiencies of the low-cost adsorbents in order to achieve WHO standards of drinking water quality. The paper highlights some of the synthesis routes employed for the modification of low-cost adsorbents. This updated review provides information on the different applications of low-cost adsorbents in removing pollutants and their adsorption capacities in an attempt to deploy the recent sustainable low-cost adsorbents with high removal efficiencies for water treatment. Future research should focus on the fabrication of hybrid low-cost adsorbents with multifunctional and antimicrobial properties. In addition, life cycle assessment (LCA) should be conducted to reveal the environmental burdens associated with the modification of the low-cost adsorbent to improve their removal efficiencies.

Revisit the Role of Salinity in Heterogeneous Catalytic Ozonation: The Trade-Off between Reaction Inhibition and Mass Transfer Enhancement.

Heterogeneous catalytic ozonation (HCO) is an effective technology for advanced wastewater treatment, while the influence of coexisting salts remains unclear and controversial. Here, we systematically explored the influence of NaCl salinity on the reaction and mass transfer of HCO through lab experiments, kinetic simulation, and computational fluid dynamics modeling, and proposed that the trade-off between reaction inhibition and mass transfer enhancement would affect the pollutants degradation pattern under varying salinity. The increase of NaCl salinity decreased ozone solubility and accelerated the futile consumption of ozone and hydroxyl radicals (•OH), and the maximum •OH concentration under 50 g/L salinity was only 23% of that without salinity. However, the increase of NaCl salinity also significantly reduced the ozone bubble size and enhanced the interphase and intraliquid mass transfer, with the volumetric mass transfer coefficient being 130% higher than that without salinity. The trade-off between reaction inhibition and mass transfer enhancement shifted under different pH values and aerator pore sizes, and the oxalate degradation pattern would change correspondingly. Besides, the trade-off was also identified for Na2SO4 salinity. These results emphasized the dual influence of salinity and offered a new theoretical perspective on the role of salinity in the HCO process.

Occurrence of Klebsiella pneumoniae ST244 and ST11 extensively drug-resistant producing KPC, NDM, OXA-370 in wastewater, Brazil.

To investigate the occurrence of carbapenem-resistant Klebsiella pneumoniae (CRKP) and their clonal relationships from hospital and municipal wastewater treatment plants (WWTPs). Eighteen K. pneumoniae strains recovered from three WWTPs were identified by MALDI-TOF. The antimicrobial susceptibility were evaluated by disk-diffusion and the carbapenemases production by Carbapenembac®. The carbapenemases genes were investigated by real-time PCR and the clonal relationship through multi-locus sequence typing (MLST). Thirty nine percent (7/18) of isolates were classified as multidrug-resistant (MDR), 61.1% (11/18) extensively drug-resistant (XDR) and 83.3% (15/18) showed carbapenemase activity. Three carbapenemase-encoding genes were found, blaKPC (55%), blaNDM (27.8%) and blaOXA-370 (11.1%) as well five sequencing types ST11, ST37, ST147, ST244 and ST281. ST11 and ST244, sharing four alleles were grouped into clonal complex 11 (CC11). Our results show the importance of monitoring antimicrobial resistance in WWTPs effluents to minimize the risk of spreading bacterial load and ARGs in aquatic ecosystems, using advanced treatment technologies to reduce these emerging pollutants at WWTPs.