Ozonation as a pretreatment process for nanofiltration brines: Monitoring of transformation products and toxicity evaluation

Considerable interest has been given to using nanofiltration (NF) in lieu of reverse osmosis for water reclamation schemes due to lower energy consumption, higher flux rates while ensuring good micropollutants rejection. The application NF results in the generation of a large concentrated waste stream. Treatment of the concentrate is a major hurdle for the implementation of membrane technologies since the concentrate is usually unusable due to a large pollutants content. This work focuses on the application of ozonation as pretreatment of urban NF concentrates, the generation of transformation products and their relative toxicity. Three pharmaceutical micropollutants largely encountered in water cycle were selected as target molecules: acetaminophen, carbamazepine and atenolol. Through accurate-mass Q-TOF LC-MS/MS analyses, more than twenty ozonation products were detected, structure proposals and formation pathways were elaborated. Attempts were made to understand the correlation between the transformation products and acute toxicity on Vibrio fischeri strain. It is the first time that an integrated study reported on the ozonation of pharmaceuticals in urban membrane concentrates, in terms of transformation products, kinetics, degradation mechanisms, as well as toxicity assessment.

Ozonation of the oxybenzone, octinoxate, and octocrylene UV-filters: Reaction kinetics, absorbance characteristics, and transformation products

UV-filters (UVFs) are active ingredients in personal care products that protect skin from exposure to UV light. Environmentally-relevant concentrations of UVFs have recently been linked to toxicity in aquatic organisms, necessitating research into improved UVF removal in water/wastewater treatment. Here, we investigated ozonation of the three most commonly employed UVFs: octinoxate (OMC), octocrylene (OC), and oxybenzone (OXY). Specific second-order rate constants for UVF reaction with ozone were identified as follows: OMC, 5.25×10⁴M^-1s^-1; OC, 1.58M^-1s^-1; OXY (neutral), 3.80×10²M^-1s^-1; and, OXY (anion), 1.51×10⁶M^-1s^-1. These kinetic parameters indicated that OMC and OXY undergo significant (2-log or greater) transformation for typical ozone exposures in disinfection processes; however, minimal oxidation is expected for OC. UV absorbance mapping was employed to characterize the loss of UVF activity (i.e., absorbance across the UV-A, UV-B, and UV-C ranges) during ozonation. These 4-dimensional maps also confirmed ozone attack mechanisms, namely reaction at phenolate (OXY) and olefin (OMC, OC) groups. Primary transformation products from these reactions were identified for all three UVFs of concern. For OC and OXY, the benzophenone structure is conserved, suggesting that transformation products retain toxicity concerns.

Evaluation of the detoxification efficiencies of coking wastewater treated by combined anaerobic-anoxic-oxic (A2O) and advanced oxidation process

Coking wastewater contains many types of toxic and hazardous pollutants that have serious toxic effects on human beings as well as aquatic organisms. However, few studies have evaluated the detoxification efficiencies of the treatment processes that are extensively performed in operational coking wastewater treatment plants (WWTPs). This study investigates the detoxification efficiencies of a combined anaerobic-anoxic-oxic (A²O)-ozonation and A²O-Fenton oxidation process in two coking WWTPs using an acute immobilization test for Daphnia magna, acute toxicity test for adult zebrafish, embryo toxicity test for zebrafish and the comet assay. The raw coking wastewaters displayed high acute daphnia and fish toxicity, zebrafish embryo toxicity and genotoxicity. The A²O processing unit effectively removed acute and embryo toxicity, but not genotoxicity. In addition, the A²O effluent quality did not meet the integrated wastewater discharge standard in China (GB18918-2002). The ozonation and Fenton oxidation units used as post-treatments in these two plants not only treated the coking wastewater to the discharge standard but also reduced the genotoxicity. However, the final effluents still showed potential genotoxicity after high dilution. The results suggest that the discharge of treated coking wastewater probably poses potential risks to human health and the environment even if it met regulatory standards.

Preparation of pompon-like ZnO-PANI heterostructure and its applications for the treatment of typical water pollutants under visible light

Until now, the treatment of multiple water pollutants by using one simple material has still been a challenge. Pompon-like ZnO-Polyaniline heterostructures with different content of Polyaniline as out-layer were synthesized by hydrothermal method and hybridization. Their several applications were subsequently investigated for water pollutants treatment including photo-degradation of organic pollutants, photo-induced adsorption of heavy metal ions (Hg(II), Cr(VI)) and inactivation of Pathogenic bacteria (E. coli bacteria and staphylococcus aureus) under visible light. The results indicate that the aforementioned pollutants can be effectively removed by Pompon-like ZnO-Polyaniline heterostructure. The enhanced photochemical performance is attributed to: (1) the improved monodispersity and relative large specific surface area of pompon-like ZnO-PANI enhance the production of photo-induced OH and O₂^-; (2) the high separation efficiency of photo-generated electron-hole pairs, which comes from the synergistic effect of P-N type heterojunction.

Graphene oxide-enzyme hybrid nanoflowers for efficient water soluble dye removal

High efficient enzyme immobilization on carbon based conductive supports could provide wide applications in energy and environmental science. Here, we synthesized a 3D flower-like structured self-assembly hybrid nanocomposite with copper phosphate, laccase, graphite oxide (GO) and carbon nanotubes (CNTs) via a facile one-pot strategy under mild conditions. The prepared nanocomposite exhibited very high enzyme loading and improved laccase activity. During the formation of the nanocomposite, the copper phosphate-laccase petals were interwined by CNTs, and GO nanosheets were further coated on the petal surface. Such a configuration ensured high enzyme loading between the GO sheets and good mass transfer efficiency between immobilized enzyme and substrate, which was confirmed by the kinetics test. We further deposited the immobilized enzyme onto electrodes and observed significantly improved direct electron transfer efficiency. Furthermore, higher dye removal efficiency was observed with the immobilized enzyme. The highly efficient enzyme immobilization strategy provides significant opportunity for its application in bioelectronics and wastewater treatment.

Application of calcium peroxide in water and soil treatment: A review

Calcium peroxide (CP) has been progressively applied in terms of environmental protection due to its certain physical and chemical properties. This review focuses on the latest progresses in the applications of CP in water and soil treatment, including wastewater treatment, surface water restoration and groundwater and soil remediation. The stability of CP makes it an effective solid phase to supply H₂O₂ and O₂ for aerobic biodegradation and chemical degradation of contaminants in water and soil. CP has exerted great performance in the removal of dyes, chlorinated hydrocarbons, petroleum hydrocarbons, pesticides, heavy metals and various other contaminants. The research progress in the encapsulation technologies of CP with other materials and the preparation of CP nanoparticles were also presented in this review. Based on the summarized research progresses, the perspective of CP application in the future was proposed.

Novel Wastewater-Based Epidemiology Approach Based on Liquid Chromatography-Tandem Mass Spectrometry for Assessing Population Exposure to Tobacco-Specific Toxicants and Carcinogens

Tobacco smoking remains an important public health issue worldwide. Assessment of exposure to tobacco-related toxicants and carcinogens at the population level is thus an essential population health indicator. This can be achieved by wastewater-based epidemiology (WBE), which relies on the analysis of biomarkers in wastewater. However, required analytical methods for the simultaneous measurement of tobacco-related toxicants and carcinogens in wastewater are not available. In this study, a new analytical procedure was developed and validated to measure tobacco-related alkaloids, carcinogens, and their metabolites in raw wastewater, including anabasine (ANABA), anatabine (ANATA), cotinine (COT), trans-3'-hydroxycotinine (COT-OH), N-nitrosoanabasine (NAB), N-nitrosoanatabine (NAT), N-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), NNAL-N-β-glucuronide, and NNAL-O-β-glucuronide. Different parameters were optimized for the solid-phase extraction procedure and instrumental analysis using liquid chromatography-tandem mass spectrometry. The optimized method was fully validated, resulting in acceptable within-run and between-run precision (<8% and <10% relative standard deviation, respectively) and accuracy (<9% and <13% bias, respectively). Method quantification limits were at 0.5-120 ng/L in wastewater. Target analytes were stable in wastewater at 4 and 20 °C over 24 h. The developed method was applied to wastewater samples from two Belgian cities. Average concentrations of COT, COT-OH, ANATA, ANABA, and NAT were 5200, 2600, 30, 10, and 0.6 ng/L, respectively, while NAB, NNN, NNK, and NNAL were not detected in the samples. With the developed robust analytical method, our study provided the first insight into the population exposure to both toxicants and carcinogens resulting from tobacco use.

Assessment of the antioxidant and antibacterial activities of different olive processing wastewaters

Olive processing wastewaters (OPW), namely olive mill wastewater (OMW) and table-olive wastewaters (TOW) were evaluated for their antibacterial activity against five Gram-positive and two Gram-negative bacteria using the standard disc diffusion and thin layer chromatography (TLC)-bioautography assays. Disc diffusion screening and bioautography of OMW were compared to the phenolic extracts of table-olive brines. Positive activity against S. aureus was demonstrated. The optimization of chromatographic separation revealed that hexane/acetone in the ratio of 4:6 was the most effective for phenolic compounds separation. A HPLC-MS analysis was performed showing that only two compounds, hydroxytyrosol and tyrosol, were the predominant phenolic compounds in all OPW. The phenolic extract of OMW generated by a semi-modern process showed the highest free radical-scavenging activity (DPPH assay) compared to the other phenolic extracts. It is apparent from the present study that OPW are a rich source of antioxidants suitable for use in food, cosmetic or pharmaceutical applications.

Decontamination of multiple heavy metals-containing effluents through microbial biotechnology

To decontaminate heavy metal-containing waste water, a microbial biotechnology was developed by using the synergy between Sulfate reducing bacteria (SRB), Bacillus cereus (B. cereus) and Camellia oleifera cake (COC). In this process the COC degradation assisted by B.cereus, created an anoxic environment and provided energy and nutrition for SRB. Both of B. cereus and SRB played significant roles through biosorption, bioaccumulation and biosurfactant production. Meanwhile, a flotation technology commonly used in many effluent treatments has been led into this system for increasing the efficiency as well. After desorption and regeneration with acid and deionized water, the biosorbents could be reused to adsorb metal ions. 97% of heavy metals removal was achieved by the proposed technology. For multiple heavy metals-containing solutions, the capacities are in the order of Cd²⁺>Zn²⁺>Cu²⁺.

Antioxidant Response in Duckweed After Exposure to Secondary Effluent from Municipal Wastewater Treatment Plant, Elazığ, Turkey

The aim of this study is to evaluate the effects of the effluent of Elazig Municipality Wastewater Treatment Plant on the oxidative defense capacity of aquatic plants (Lemna minor L. and Lemna gibba L.). For this purpose, malondialdehyde (MDA), glutathione (GSH), oxidized glutathione (GSSG), vitamin A (retinol), vitamin E (α-tocopherol), and vitamin C (Ascorbic acid) levels were determined by the HPLC (high performance liquid chromatography) in the control groups and the groups adapting to reactors fed with discharge water. The depletion of vitamins (A, E, and C), decrease of GSH/GSSG ratio, and increase of MDA that reflect a precarious state of the cell in L. minor L. and L. gibba L. were observed after exposure to wastewater. It can be suggested that the selected biomarkers are useful in understanding the biochemical mechanisms of the secondary effluents from wastewater treatment plant in L. minor L. and L. gibba L. as early warning indicators.

Applicability of Zeolite Based Systems for Ammonia Removal and Recovery From Wastewater

  Ammonia discharged in industrial effluents bears deleterious effects and necessitates remediation. Integrated systems devoted to recovery of ammonia in a useful form and remediation of the same addresses the challenges of waste management and its utilization. A comparative performance evaluation study was undertaken to access the suitability of different zeolite based systems (commercial zeolites and zeolites synthesized from fly ash) for removal of ammonia followed by its subsequent release. Four main parameters which were studied to evaluate the applicability of such systems for large scale usage are cost-effectiveness, ammonia removal efficiency, performance on regeneration, and ammonia release percentage. The results indicated that synthetic zeolites outperformed zeolites synthesized from fly ash, although the later proved to be more efficient in terms of total cost incurred. Process technology development in this direction will be a trade-of between cost and ammonia removal and release efficiencies.

Fate of the sunscreen compound oxybenzone in Cyperus alternifolius based hydroponic culture: Uptake, biotransformation and phytotoxicity

Oxybenzone (OBZ), a common ingredient in sunscreens and personal care products, has been frequently detected in effluents from municipal wastewater treatment plants and also in surface waters. OBZ is an emerging contaminant due to its adverse impacts on marine/aquatic ecosystems. To investigate the removal and degradation capacity of phytotreatment for OBZ, the common wetland plant species Cyperus alternifolius L. was exposed to this compound at 5, 25 and 50 μM for 120 h, respectively. Continuous uptake by roots and accumulation in plant tissues was observed over the exposure time, and depletion of spiked OBZ from the aqueous medium exceeded 73.9 ± 9.1% after 120 h. Similar to its fate in mammalian cells, OBZ is activated in a phase I reaction resulting in the hydroxylated metabolite 2,4-dihydroxybenzophenone (DHB). Independently, two phase II metabolites were identified as oxybenzone-glucoside (OBZ-Glu) and oxybenzone-(6-O-malonyl)-glucoside (OBZ-Mal-Glu) by LC-MS/MS. Formation of these metabolites increased over the experimental period. To our knowledge this is the first time that DHB, OBZ-Glu and OBZ-Mal-Glu are shown to be formed in higher plant tissues. Furthermore, plant defense systems-antioxidative enzymes (SOD, CAT, APOX and POX) were found to be elevated to counteract stress caused by exposure to OBZ. This study presents the huge potential of aquatic plants to cope with benzophenone type UV filters in contaminated water bodies.

Biosorption of methylene blue by nonliving biomass of the brown macroalga Sargassum hemiphyllum

The ability of Sargassum hemiphyllum to remove methylene blue (MB) from aqueous solution was evaluated. Batch experiments were conducted to examine the effects of parameters such as initial pH, contact time, biomass dose and initial dye concentration on adsorption capacity. S. hemiphyllum before and after MB adsorption was characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The Langmuir isotherm model provided the best correlation with experimental data, and the monolayer biosorption capacity was 729.93 mg·g-1 within 120 min using 0.5 g·L-1 algal biomass and pH of 5. The pseudo-second-order kinetic model accurately described the adsorption kinetics data. Thermodynamic parameters (ΔG0, ΔH0 and ΔS0) at temperature ranges of 293-313 K demonstrated that biosorption is an endothermic and spontaneous reaction. FT-IR analysis showed that the hydroxyl, amine and carboxyl functional groups on the surface of the algae were the most important functional groups for biosorption of MB. XPS analysis indicated that the algal biomass combined with MB molecules through -NH2 groups. These results suggest that S. hemiphyllum is a favorable biosorbent for removing MB dye from wastewater.

Cytotoxic effects of seven Tunisian hospital wastewaters on the proliferation of human breast cancer cell line MDA-231: correlation with their chemical characterization

Hospital wastewaters contain large amounts of pharmaceutical residues, which may eventually be discharged into the aquatic environment through wastewater treatment plants, raising the question of their impact on human and environmental health. This has prompted the launch of several monitoring studies into the most commonly administered compounds in urban wastewater. The aim of this study was, therefore, to explore the cytotoxic potential of wastewaters samples collected from seven hospitals in Tunisia. The physicochemical analyses showed a large fluctuation of certain parameters in the collected samples, such as chemical oxygen demand (ranged from 860 to 1720 mg L^-1), biochemical oxygen demand (ranged from 385 to 747 mg L^-1), total organic carbon (ranged from 256 to 562 g L^-1), total suspended solids (ranged from 905 to 1450 mg L^-1), conductivity (ranged from 3.31 to 7.14 μsm/cm), and turbidity (ranged from 100 to 480 NTU). The analysis using inductively coupled plasma mass spectrometry (ICP-MS) also showed that hospital wastewater contains high concentrations of Hg (ranged from 0.0024 to 0.019 mg L^-1). This could be explained by the variation of the activity and the services in certain hospitals compared to others. All hospital wastewater samples induced the proliferation of human breast cancer cell line MDA-231, even at low concentrations (20 μL/assay). Moreover, the maximum induction reached at the concentration of 60 μL/assay in wastewater samples from hospitals located in Monastir, Sidi Bouzid, Mahdia, and Sfax with percentages of induction up to 42.33, 14, 7.61, and 5.42%, respectively. These observations could be due to the presence of endocrine disrupting compounds (EDCs) in these wastewaters. Given this, our results evidenced the potential risk of these hospital effluents to environmental and public health.

Application for oxytetracycline wastewater pretreatment by Fenton iron mud based cathodic-anodic-electrolysis ceramic granular fillers

In this study, Fenton iron mud applied as main raw material of cathodic-anodic-electrolysis ceramic granular fillers (ICMF) in a continuous reactor, which were used to pretreat oxytetracycline (OTC) wastewater. The ICMF was characterized by Scanning Electron Microscope and Energy Dispersive Spectrometer analysis. The effects of pH value, hydraulic retention time, OTC concentrations and aeration on removal efficiency of total organic carbon (TOC) and OTC were studied. The degradation byproducts of OTC were analyzed by UV-2450, High Performance Liquid Chromatography and Liquid Chromatography-mass Spectrometry. The SEM images showed that the surface ICMF was porous. This system had a higher stability, and good removal efficiency of TOC of 80.5% and OTC of 98.5% under the optimal conditions, which were influent pH of 3, HRT of 4 h, and anaerobic condition. After running for 60 d, the removal efficiency of TOC was stable and the ICMF did not become hardened. The reactor was back washed by acid solution (pH: 1) in 20 d approximately. This paper provides useful information for approaching in wastewater pretreatment and recycling the Fenton iron mud.

Comparison of coagulation, ozone and ferrate treatment processes for color, COD and toxicity removal from complex textile wastewater

In this study, the comparative performance of coagulation, ozone, coagulation + ozone + coagulation and potassium ferrate processes to remove chemical oxygen demand (COD), color, and toxicity from a highly polluted textile wastewater were evaluated. Experimental results showed that ferrate alone had no effect on COD, color and toxicity removal. Whereas, in combination with FeSO₄, it has shown the highest removal efficiency of 96.5%, 83% and 75% for respective parameters at the optimal dose of 40 mgL^-1 + 3 ml FeSO₄ (1 M) in comparison with other processes. A seed germination test using seeds of Spinach (Spinacia oleracea) also indicated that ferrate was more effective in removing toxicity from contaminated textile wastewater. Potassium ferrate also produces less sludge with maximum contaminant removal, thereby making the process more economically feasible. Fourier transform infrared spectroscopy (FTIR) analysis also shows the cleavage of the chromophore group and degradation of textile wastewater during chemical and oxidation treatment processes.

Influence of temperature and pH on the anammox process: A review and meta-analysis

The anammox (anaerobic ammonium oxidation) process was considered a very efficient and economic wastewater treatment technology immediately after its discovery in 1995, thus research in this field was intensified. The anammox process is characterised by a high temperature optimum and is very sensitive to both temperature and pH fluctuations. The process can also be inhibited by many factors, including by its substrates, i.e. nitrite and ammonium (or its unionised forms: free ammonia and free nitrous acid). This paper presents a comprehensive study of the most important and recent findings on the influence of two parameters that are crucial in wastewater treatment, i.e. temperature and pH. Because both parameters may influence the anammox process simultaneously, a meta-analysis was conducted of the data from the literature. Although meta-analysis is commonly used in medical research, mathematical analysis of the literature data has become an interesting and important step in the environmental sciences. This paper presents information on the influence of both temperature and pH on process efficiency and microbial composition. Additionally, the responses of different operating systems on both temperature and pH changes are described. Moreover, the role of both adaptation to changed conditions and of pH control as well as indicated areas of process operation are discussed.

Mallards (Anas platyrhynchos) and wastewater ponds, Part I: Mallard ducks overwintering at a northern wastewater treatment pond

In northern urban areas, wastewater treatment ponds (WWTPs) may provide a thermal refuge during winter (~10°C) that is used by normally migratory mallards (Anas platyrhynchos). On the ponds, mallards may experience stress due to crowding, or through the ingestion of WWTP water, be exposed to a diverse array of synthetic chemicals, which may have adverse health effects. Photographic sampling was used to assess mallard sex ratios and behavioural patterns throughout the late winter on wastewater ponds in Edmonton, Canada. The WWTP mallard population was large (>1000 birds), but temporally variable and consistently male-dominated. Locomotion and dabbling were the primary behaviors observed; aggression was rarely observed, which suggests crowding stress was low or absent. Mallard abundance tended to be higher at lower air temperatures, suggesting that WWTP ponds acted as a thermal refuge. Stable isotope analysis of carbon and nitrogen from duck feces and potential food sources indicated that mallards were not feeding at the site, or on invertebrates or select waste grain from offsite. Rather, ducks either consumed an undetermined food source or were feeding very little. Taken together, the data suggest that winter use of northern WWTP ponds may serve as an alternative to migration, whether this strategy benefits or harms mallards likely depends on winter severity, and not on WWTP pond characteristics or water quality.

Development of collection, storage and analysis procedures for the quantification of cyclic volatile methylsiloxanes in wastewater treatment plant effluent and influent

A reliable and accurate method for collection and analysis of octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6) in wastewater treatment plant influent, effluent and surface waters was developed. Due to the use of cyclic volatile methylsiloxanes (cVMS) in industrial and consumer products including some personal care products, the wastewater stream represents a potential post-use disposal route and cVMS may subsequently enter the environment through wastewater treatment plant effluents. cVMS in the environment has come under increased regulatory scrutiny with regard to their potential for persistence, bioaccumulation and toxicity indicating a need for monitoring programs with reliable analytical methods. The developed method is unique in that it utilizes low density polyethylene (LDPE) to inhibit loss of cVMS during sampling and transport to the laboratory. The samples are then processed with a simple solvent extraction and analyzed by gas chromatography mass spectrometry with stable isotope internal standard calibration. This method utilizes readily available laboratory supplies and requires minimal field processing, reducing contamination potential. Method detection limits of 17 ng/L, 57 ng/L, and 20 ng/L were obtained for D4, D5, and D6, respectively. Additionally a robust quality control program was employed to ensure sample integrity. The method described herein can readily be adopted for use in monitoring studies where the amount of cVMS in water samples will be quantified.

Mallards (Anas platyrhynchos) and wastewater ponds, Part II: Developmental, physiological, morphological and behavioural effects of ingestion of secondary clarified effluent water

Rather than migrating, mallard ducks may choose to overwinter in northern cities on open-water thermal refuges, such as municipal wastewater treatment ponds, which in Edmonton, Canada, stay ≥10°C during frigid winter months. Refuging mallards spend appreciable time daily on these ponds and hydrate using secondary clarified municipal wastewater (SCEW). We aimed to determine if SCEW ingestion affected mallard health. To this end, we gavaged newly hatched mallards (domesticated Pekin strain) over their first month with SCEW, as well as water representing negative and positive controls (municipal tap water, and the primary active ingredient from birth control pills, 17α-ethinyl estradiol (EE2), respectively). The gavage of SCEW did not affect mass of the body, liver, spleen or heart, but was associated with small increases in beak and wing chord length. In the positive control, EE2 gavage caused similar responses, but also increased tarsus and phallus length. The increases likely owed to the stimulatory effects of estrogenic substances on bone and phallus development. For the biotransformation enzyme CYP2H1, gene expression was numerically increased by both SCEW and EE2. In terms of behavior, SCEW and EE2 gavage reduced two infrequently detected behaviours, pecking and resting alone. Our results suggest that SCEW ingestion would be unlikely to cause any overt health effects in adults, but may evoke subtle, covert effects nevertheless.

Multi-class determination of pharmaceuticals in wastewaters by solid-phase extraction and liquid chromatography tandem mass spectrometry with matrix effect study

In this work, a multi-class analytical method for determination of 22 frequently used pharmaceuticals was developed and validated. Analytes were from different classes for example macrolides, fluoroquinolones, tetracyclines, sulfonamides, anthelmintics, anesthetics, and others. Method was intended for analysis of aqueous samples so the sample preparation was done using solid-phase extraction (SPE). Different sorbents (C8, C18, polymeric, and ion exchange sorbents) combining different eluents (methanol, ethanol, acetonitrile, acetone, ethyl acetate) were investigated during development of sample preparation step. Samples were analyzed using HPLC-MS/MS, and therefore, chromatographic and mass spectrometer conditions were investigated. Optimal extraction efficiencies for most of the investigated analytes were obtained with Oasis HLB polymeric sorbents with acetonitrile as eluent. A study of matrix effect was carried out for wastewater treatment plant (WWTP) influent and effluent. The method was validated for linearity, detection limits and quantification limits, repeatability, and reproducibility. Method detection limits were in the range of 2.0-204.0 ng L^-1 for WWTP influent except for sulfaguanidine and dexamethasone. Also, method detection limits for WWTP effluent were from 1.0 to 115.4 ng L^-1. Method was successfully applied for analysis of real wastewater samples from municipal wastewater treatment plant. In the influent, pharmaceuticals from all investigated groups were present and the concentrations were from 50.0 to 4914.3 ng L^-1 for influent and 26.9 to 1699.2 ng L^-1 for effluent. It was also reported that some pharmaceuticals showed higher concentrations in the wastewater effluent than in the influent.

Application of ultrasound modified corn straw as adsorbent for malachite green removal from synthetic and real effluents

This work aimed to study the removal of malachite green dye from wastewaters through adsorption using raw corn straw (RCS) and ultrasound-assisted modified corn straw (MCS). RCS and MCS were prepared and characterized in detail. The characterization indicated that RCS and MCS presented favorable structures for malachite green adsorption and that the ultrasound treatment provided a disorganization of the adsorbent's crystalline regions and also caused the formation of cavities and protuberances. The adsorption study was performed by equilibrium isotherms, kinetic curves, thermodynamic parameters, and application in real effluents composed of dye mixtures and inorganic compounds. The Elovich model was suitable for the adsorption kinetics and the Freundlich model was appropriate to represent the equilibrium. The maximum experimental adsorption capacities were 200 mg g^-1 for RCS and 210 mg g^-1 for MCS, obtained at 328 K. MCS was more effective than RCS to treat real effluents, attaining around 92% of color removal.

Can radiation chemistry supply a highly efficient AO(R)P process for organics removal from drinking and waste water? A review

The increasing role of chemistry in industrial production and its direct and indirect impacts in everyday life create the need for continuous search and efficiency improvement of new methods for decomposition/removal of different classes of waterborne anthropogenic pollutants. This review paper addresses a highly promising class of water treatment solutions, aimed at tackling the pressing problem of emerging contaminants in natural and drinking waters and wastewater discharges. Radiation processing, a technology originating from radiation chemistry studies, has shown encouraging results in the treatment of (mainly) organic water pollution. Radiation ("high energy") processing is an additive-free technology using short-lived reactive species formed by the radiolysis of water, both oxidative and reducing, to carry out decomposition of organic pollutants. The paper illustrates the basic principles of radiolytic treatment of organic pollutants in water and wastewaters and specifically of one of its most practical implementations (electron beam processing). Application examples, highlighting the technology's strong points and operational conditions are described, and a discussion on the possible future of this technology follows.

Separating grey- and blackwater in urban water cycles - sensible in the view of misconnections?

The infrastructure approach SEMIZENTRAL has been developed for fast growing cities, to meet their challenges regarding water supply as well as biowaste and wastewater treatment. The world's first full-scale SEMIZENTRAL Resource Recovery Center (RRC) has been implemented in Qingdao (PR China). Greywater (GW) and blackwater (BW) are collected and treated separately. Measurement of influent concentrations differ significantly from the design values. Thus, the operation strategy for the RRC had to be adapted. Amongst other reasons, the changed influent characteristic was caused by misconnections of GW and BW sewers. Already a misconnection rate of 6-8% requires an extension of the GW treatment process for nitrification/denitrification to fulfill effluent standards. Hence, measures should be taken to avoid or reduce misconnections. Nonetheless, in a semi-centralized scale (>10,000 inhabitants) a 100% avoidance might not be possible. Thus, consequences from misconnections should be considered during the design of source-oriented infrastructure systems.

Environmentally friendly cellulose-based polyelectrolytes in wastewater treatment

Natural-based polyelectrolytes (PELs), with all the advantages coming from being produced from renewable and biodegradable sources, are a potential solution for the removal of dyes from wastewater. In this work, surplus Eucalyptus bleached cellulose fibres from a paper mill were modified to increase the charge and solubility of cellulose. First, reactive aldehyde groups were introduced in the cellulose backbone by periodate oxidation of cellulose. Further modification with alkylammonium produced positively charged cellulose-based PELs. The final products were characterized by several analytical techniques. The PEL with the highest substitution degree of cationic groups was evaluated for its performance in decolouration processes, bentonite being used as aid. This was found to be effective for colour removal of either anionic or cationic dyes. Bio-PELs can thus be considered as very favourable eco-friendly flocculation agents for decolouration of harsh effluents from several industries, considering their biodegradable nature and thus the ability to produce less sludge.