O lodo de esgoto, também denominado biossólido, depois de tratado adequadamente, constitui fonte de matéria orgânica, micro e macro-nutrientes para o crescimento das plantas. A aplicação do lodo de esgoto no solo pode trazer benefícios tais como: distribuição em áreas para produção agrícola, recuperação de solos perdidos por erosão, aplicação em áreas de reflorestamento. Os lodos de esgotos, entretanto, são resíduos que contem patógenos, metais pesados, e poluentes orgânicos, entre estes os compostos orgânicos voláteis (COVs). A resolução CONAMA nº 375 em vigor no Brasil, assim como as regulamentações de outros países, não exigem valores limites para alguns COVs considerados prioritários. Uma base de dados sobre COVs em lodos de esgoto é necessário para estabelecer valores limites nos lodos usados para fins agrícolas. O presente trabalho evidenciou a presença de COVs em concentrações significativas nas amostras de lodo coletadas nas Estações de Tratamento de Esgoto (ETE) na Região Metropolitana de São Paulo (RMSP), Jundiaí, Vinhedo e Americana. Na ETE da RMSP foram encontrados vários COVs em concentrações significativas. Dentre os COVs identificados, apenas 1,4-diclorobenzeno e naftaleno apresentam valores permitidos em solo agrícola (390 e 120 µmg/kg, respectivamente) e valores de concentrações muito acima desses limites foram encontrados para as amostras de lodo da ETE de RMSP (845 a 2037 e 901 a 5670 µmg/kg, respectivamente). Os resultados obtidos neste trabalho, embora não forneçam dados suficientes para uma imediata tomada de decisão, permitem fornecer subsídios técnicos para iniciar uma base de dados sobre COVs em lodo de esgoto que, futuramente, utilizando-se metodologias adequadas, será útil para se realizar uma revisão das regulamentações vigentes para lodo de esgoto com finalidade agrícola. / The sewage sludge also entitled biosolid, after adequate treatment, is source of organic matter, micro and macronutrients for plants growth. The application of sewage sludge in soil may provide some benefits like: distribution in areas for agricultural production, recovery of degraded soil by erosion, application in areas of reforestation. However, sewage sludges are residues that contain phatogens, heavy metals, organic pollutants, such as volatile organic compounds (VOCs). The current resolution in Brazil (CONAMA nº 375), as well as regulations from other countries do not establish acceptable levels for some priority VOCs. It is necessary to establish data a base related to VOCs in sewage sludge for agricultural use to be able to present acceptable levels of them. The present work reports the presence of VOCs at significant levels in sewage sludge samples collected at sewage treatment stations (ETE) in the Metropolitan Region of São Paulo city (RMSP), Jundiaí, Vinhedo and Americana. Among VOCs identified, only 1,4 dichlorobenzene and naphthalene are regulated for use in agricultural soil (390 and 120 µg/kg, respectively) and levels found for sewage sludge samples from RMSPETE were higher than those regulated limits (845 to 2037 and 901 to 5670 µg/kg, respectively). Although results obtained in this study do not provide enough data for an immediate decision, results will be useful to start a data base regarding to VOCs in iv sewage sludge for agricultural use that, using adequate methodologies, will permit a review of current regulations on VOCs for agricultural use.

Du fait du coût élevé de certains matériaux adsorbants d’intérêt pour le traitement de la micropollution organique, l’étude a porté sur la régénération de matériaux adsorbants de type zéolithes hydrophobes et monolithe de carbone dans le cas de l’adsorption du bisphénol A et du diclofénac comme micropolluants réfractaires. Des procédés d’oxydation avancée impliquant des espèces radicalaires HO• (réaction de Fenton, électro-Fenton) et SO₄• – (activation de persulfate par voie thermique) ont été utilisés pour assurer la régénération des matériaux par désorption et dégradation oxydative des polluants fixés. La production de radicaux HO• au sein de la phase aqueuse circulant au niveau de l’adsorbant n’est pas suffisamment efficace pour sa régénération. Il a donc été envisagé de générer les radicaux au plus près des molécules adsorbées. Au cours de ce travail, une méthode sensible d’analyse par polarographie de H₂O₂ a été développée et validée pour le suivi des expériences avec les procédés mettant en jeu la réaction de Fenton. Pour différentes zéolithes, le catalyseur de la réaction de Fenton à base de fer a été incorporé préalablement dans la zéolithe. Pour le monolithe de carbone, les propriétés de conduction du matériau ont été mises à profit en l’utilisant comme cathode pour l’application du procédé électro-Fenton permettant de produire les radicaux HO• directement au sein du matériau. Cela a conduit à améliorer les performances de la régénération avec toutefois une diminution de son efficacité au cours de cycles successifs adsorption/régénération. / The elimination of organic micropollutants often requires the use of adsorption processes among the water treatments. The aim of our study is to regenerate two expensive materials (hydrophobic zeolites and carbon monoliths) to increase their life expectancy and decrease their investing cost. Two organic contaminants were targeted : diclofenac and bisphenol A, which are refractory pollutants. Advanced oxidation processes involve radical species, HO• (Fenton and electro-Fenton reactions) and SO₄• – (thermal activation of persulfate ion). These oxidants were used to decompose the adsorbed pollutants and thus regenerate the adsorbents. The HO• production, within the core of aqueous phase, did not reach satisfactory regeneration, and a loss of adsorption capacity was observed. Furthermore, during this study, a sensitive polarographic analytical method was developed and validated for the quantification of H₂O₂ in the aqueous phase. This method was used to follow in situ the Fenton reaction. The location of the catalyst in a closer vicinity of the adsorbed species was then optimized and the iron catalyst was impregnated in the host, prior to the adsorption, on different types of hydrophobic zeolites. Concerning carbon monolith, the electro-Fenton process was carried out using the material as the cathode thanks to its electrical conductivity. Consequently, HO• are produced in the porosity of monolith. This latter property enhanced the degradation of adsorbed solutes. The overall performances were increased compared to the homogeneous Fenton process. Nonetheless, a decrease of the adsorption capacities with adsorption-regeneration cycles was observed.

Conselho Nacional de Desenvolvimento Científico e Tecnológico / The presence of organic contaminants in the environment and in food have become a major concern due to the harmful effects to living organisms. Such contaminants may be pesticides used in agriculture for the control of pests, transformation products formed in the environment or through chemical processes, such as water treatment, and more recently pharmaceuticals and personal care products. Therefore, it is necessary to use sample preparation procedures and detection systems able to detect a variety of organic contaminants in trace level present in complex matrices, such as food and environmental samples. Thus, this study aims to: (1) address the use of high resolution mass spectrometry (HRMS) for the identification and quantification of organic contaminants in fish fillet using two acquisition data modes (full scan and all ions MS/MS) and to optimize QuEChERS method as sample preparation (PAPER 1); (2) present a second quantitative application of the use of QuEChERS method and HRMS for fruit samples (apple, pear and grape) in full scan mode, as well as to apply the proposed method for commercial fruit samples (PAPER 2) and (3) optimize and use QuEChERS method for extracting ionophore antimicrobials in poultry litter, followed by its quantification by LC-MS/MS and identification of transformation products by LC-QToF/MS after three different composting processes (PAPER 3). The three papers presented the importance of sample preparation optimization, QuEChERS, in order to obtain proper recovery of organic contaminants, besides to minimize the matrix effects caused by interferences in the extract. As the use of HRMS, which proved to be a very effective analytical tool for combining high resolution and mass accuracy, for identification and quantification of target organic contaminants, transformation products and metabolites in complex matrices using a rapid chromatographic run. / A presença de contaminantes orgânicos no meio ambiente e em alimentos têm se tornado uma grande preocupação devido aos efeitos nocivos aos seres vivos. Tais contaminantes podem ser desde agrotóxicos empregados na agricultura para o controle de pragas, produtos de transformação formados no meio ambiente ou através de processos químicos, como o tratamento de água, e mais recentemente fármacos e produtos de cuidado pessoal. Com isso, tem-se a necessidade de empregar procedimentos de preparo de amostra e sistemas de detecção capazes de detectar uma variedade de contaminantes orgânicos em nível de traços presentes em matrizes complexas como alimentos e amostras ambientais. Portanto, o presente trabalho tem como objetivos: (1) abordar o emprego da espectrometria de massas de alta resolução (HRMS) para a identificação e quantificação de contaminantes orgânicos em filé de peixe utilizando dois modos de aquisição de dados (full scan e all ions MS/MS) e otimizar o método QuEChERS para o preparo da amostra (ARTIGO 1); (2) apresentar uma segunda aplicação quantitativa do uso de QuEChERS e HRMS para amostras de frutas (maçã, pera e uva) no modo full scan, bem como aplicar o método proposto em amostras reais de frutas (ARTIGO 2) e (3) otimizar e empregar o método QuEChERS para a extração de antimicrobianos ionóforos em cama de frango, seguido de quantificação por LC-MS/MS e identificação de produtos de transformação por LC-QToF/MS após três diferentes processos de compostagem (ARTIGO 3). Os três artigos apresentados abordam a importância da otimização do procedimento de preparo de amostra, QuEChERS, a fim de obter recuperação adequada de contaminantes orgânicos, além de minimizar os efeitos de matriz causados pelos interferentes presentes no extrato. Assim como o uso de HRMS, a qual demonstrou ser uma ferramenta analítica bastante eficiente, por combinar alta resolução e exatidão de massa, para identificação e quantificação de contaminantes orgânicos alvo, produtos de transformação e metabólitos em matrizes complexas utilizando uma análise cromatográfica rápida.

O lodo de esgoto, também denominado biossólido, depois de tratado adequadamente, constitui fonte de matéria orgânica, micro e macro-nutrientes para o crescimento das plantas. A aplicação do lodo de esgoto no solo pode trazer benefícios tais como: distribuição em áreas para produção agrícola, recuperação de solos perdidos por erosão, aplicação em áreas de reflorestamento. Os lodos de esgotos, entretanto, são resíduos que contem patógenos, metais pesados, e poluentes orgânicos, entre estes os compostos orgânicos voláteis (COVs). A resolução CONAMA nº 375 em vigor no Brasil, assim como as regulamentações de outros países, não exigem valores limites para alguns COVs considerados prioritários. Uma base de dados sobre COVs em lodos de esgoto é necessário para estabelecer valores limites nos lodos usados para fins agrícolas. O presente trabalho evidenciou a presença de COVs em concentrações significativas nas amostras de lodo coletadas nas Estações de Tratamento de Esgoto (ETE) na Região Metropolitana de São Paulo (RMSP), Jundiaí, Vinhedo e Americana. Na ETE da RMSP foram encontrados vários COVs em concentrações significativas. Dentre os COVs identificados, apenas 1,4-diclorobenzeno e naftaleno apresentam valores permitidos em solo agrícola (390 e 120 µmg/kg, respectivamente) e valores de concentrações muito acima desses limites foram encontrados para as amostras de lodo da ETE de RMSP (845 a 2037 e 901 a 5670 µmg/kg, respectivamente). Os resultados obtidos neste trabalho, embora não forneçam dados suficientes para uma imediata tomada de decisão, permitem fornecer subsídios técnicos para iniciar uma base de dados sobre COVs em lodo de esgoto que, futuramente, utilizando-se metodologias adequadas, será útil para se realizar uma revisão das regulamentações vigentes para lodo de esgoto com finalidade agrícola. / The sewage sludge also entitled biosolid, after adequate treatment, is source of organic matter, micro and macronutrients for plants growth. The application of sewage sludge in soil may provide some benefits like: distribution in areas for agricultural production, recovery of degraded soil by erosion, application in areas of reforestation. However, sewage sludges are residues that contain phatogens, heavy metals, organic pollutants, such as volatile organic compounds (VOCs). The current resolution in Brazil (CONAMA nº 375), as well as regulations from other countries do not establish acceptable levels for some priority VOCs. It is necessary to establish data a base related to VOCs in sewage sludge for agricultural use to be able to present acceptable levels of them. The present work reports the presence of VOCs at significant levels in sewage sludge samples collected at sewage treatment stations (ETE) in the Metropolitan Region of São Paulo city (RMSP), Jundiaí, Vinhedo and Americana. Among VOCs identified, only 1,4 dichlorobenzene and naphthalene are regulated for use in agricultural soil (390 and 120 µg/kg, respectively) and levels found for sewage sludge samples from RMSPETE were higher than those regulated limits (845 to 2037 and 901 to 5670 µg/kg, respectively). Although results obtained in this study do not provide enough data for an immediate decision, results will be useful to start a data base regarding to VOCs in iv sewage sludge for agricultural use that, using adequate methodologies, will permit a review of current regulations on VOCs for agricultural use.

Doctor of Philosophy / Department of Biochemistry / Lawrence C. Davis / The fate and bioavailability of organic contaminants in plants is a major ecological and human health concern. Current wet chemistry techniques that employ strong chemical treatments and extractions with volatile solvents, such as GC-MS, HPLC, and radiolabeling, although helpful, degrade plant tissue resulting in the loss of spatial distribution and the production of artifacts. Synchrotron radiation infrared microspectroscopy (SR-IMS) permits direct analysis of plant cell wall architecture at the cellular level in situ, combining spatially localized information and chemical information from the IR absorbances to produce a chemical map that can be linked to a particular morphology or functional group. This study demonstrated the use of SR-IMS to probe biopolymers such as cellulose, lignin, and proteins in the root tissue of hydroponically grown sunflower and maize plants as well as to determine the fate and effect of several organic contaminants in those root tissues. Principal components analysis (PCA), a data compression technique, was employed to reveal the major spectral variances between untreated and organic contaminant treated root tissues. Treatment with 1H-benzotriazole (BT) caused alterations to the lignin component in the root tissue of plants. The BT was found in xylem and epidermal tissue of sunflower plants but not associated with any particular tissue in maize roots. 2,4-dinitrotoluene (2,4-DNT) and 2,6-dinitrotoluene (2,6-DNT) altered the pectin and polysaccharide structure in both maize and sunflower. SR-IMS revealed the reduction of DNTs to their aromatic amine form in the vascular and epidermal tissues at low concentration. At high concentration, DNTs appeared to be associated with all the plant tissues in maize and sunflower. Exposure of sunflower and maize to 2,6-dichlorophenol (2,6-DCP) caused alterations to the polysaccharide and protein component of the root tissue. In some cases, phenolic compounds were observed in the epidermal tissue of maize and sunflower roots. The results of this research indicate that SR-IMS has the potential to become an important analytical tool for determining the fate and effect of organic contaminants in plants.

The occurrence of organic contaminants in the drinking water value chain (from source to tap) is a growing concern for the Drinking Water industry and its consumers given the high risk these contaminants can cause to the general public. These adverse health effects include such as endocrine disruption, toxicity teratogenicity, mutagenicity and carcinogenicity. Some of these organic contaminants are included in national and international drinking water quality guidelines or standards. However, although there are similarities in the list of organic contaminants used by each organization or country, the organic contaminants are never the same given the local conditions. There are also noticeable differences in the concentration limits set as targets or criteria for organic contaminants for public health protection via the use of drinking water. A further question requiring the response from drinking water regulators was whether the standards listed in the international literature would be applicable in other countries like South Africa. Complicating this decision is the fact that the South African National Drinking Water Standard (SANS 241) does not adequately address this component of drinking water quality management. The current standard only provides for dissolved organic carbon (DOC), total trihalomethanes (TTHMs) and phenols. However, the standard contains a statement which specifies that if there is a known organic contaminant, that may pose a health threat, it should be included in the monitoring programme and evaluated against World Health Organization (WHO) guidelines. To safeguard Drinking Water industry customers, it was deemed necessary to investigate this matter and establish a tool to assist with the identification of a list of organic contaminants to be monitored in the drinking water value chain. To achieve this a specific procedure/protocol needed to be developed, hence the aim of this study which was to develop a generic protocol for the selection and prioritization of organic contaminants for monitoring in the drinking water value chain (from source to tap). To achieve this, a critical evaluation and synthesis of the available literature on the approaches for the selection and prioritization of organic variables of priority to the drinking water industry was undertaken as a first step. From the literature review it was evident that there are currently many selection and prioritization approaches which are characterized mainly by the purpose for which the exercise has been conducted for. Approaches that prioritize chemicals according to their importance as environmental contaminants have been developed by government agencies and private industries such as the Health Canada’s Canadian Environmental Protection Agency (CEPA), the United Kingdom’s Institute for Environmental Health (IEH), the European Community’s Oslo and Paris (OSPAR) convention exercise for the protection of the Northeast Atlantic marine environment and the European Union (EU)’s combined monitoring based and modelling based priority setting scheme (EU-COMMPs). A few approaches such as ones published by the United States Environmental Protection Agency (USEPA), address the needs of the Drinking Water industry and there is no generic approach to the selection, prioritization and monitoring of organic contaminants in the drinking water value chain. From the review of selection and prioritization approaches, a generic model was developed. The model consists of three main steps, the compilation of a “pool of organic contaminants, the selection of relevant parameters and criteria to screen organic contaminants and finally the application of criteria to select priority organic contaminants. It was however realized that these steps were not enough if the protocol to be develop will serve its purpose. Selection and prioritization approaches are typically intended to be fairly simple and quick methods for determining the health and environmental hazards posed by the use and release of chemical substances into different environmental systems. This was taken into account during the development of the current protocol. Understanding that a protocol is a predefined written procedural method in the design and implementation of tasks and that these protocols are written whenever it is desirable to standardize a method or procedure to ensure successful reproducibility in a similar set up, a generic protocol was developed based on the model. The protocol developed in this study, operates as a multidisciplinary contaminants management and proactive protocol, thus exchanges toxicological, water quality, agricultural, chemical and public health information. The protocol uses previous or readily available information as a point of departure. It seeks to address the challenge facing the water industry in managing the current and emerging organic contaminants that are relevant to public health protection via the use of drinking water. Once the protocol was developed, it was validated in a prototype drinking water value chain. The exercise comprised of testing each step of the protocol from the selection of the “pool of organic contaminants (Step I) to recommending the final priority list of organic contaminants (Step VII). The implementation was successfully conducted in the Rand Water drinking water value chain. Emphasis of expert judgment was made as each step was validated and the opinion of key stakeholders used to shape the process. During Step III of the protocol, an intensive literature review was conducted to determine organic contaminants that have been identified in ground and surface water systems across the world. As a result of this review, major groups of organic contaminants that have been found to occur in source water resources across the world were identified. The identified groups of organic contaminants include, pesticides, polynuclear aromatic hydrocarbons, per and polyfluoroorganic compounds, polycyclic aromatic hydrocarbons, alkanes and alkenes, C10-C13 Chloroalkanes, pharmaceuticals and personal care products [PPCPs], surfactants, benzotriazoles, cyanotoxins and Carbon-based engineered nanoparticles. The risk profile of the identified organic contaminants was established using the persistence, bio-accumulation and toxicity criteria and the development of water quality monographs as an information dissemination tool. A conceptual framework for the implementation of the protocol by water utilities and relevant institutions has been developed from the experiences learnt during the validation exercise and a priority list of organic contaminants for the monitoring in the drinking water value chain to be used by Rand Water and other water utilities was identified. Some of the organic contaminants on this are currently being analyzed for in The Rand Water’s routine organic monitoring programme. During the validation exercise, the following were noted, <ul> <li>During the identification of the “pool of organic contaminants” from the consulted information sources such as the WHO guidelines for drinking water quality, Health Canada drinking water quality guidelines, the USEPA drinking water quality standards, the New Zealand drinking water quality standards, USEPA IRIS database, the PAN-UK list of registered pesticides for South Africa, the IARC list for recognized carcinogens and the Department of Agriculture pesticides manuals duplications were observed. </li> <li>The time allocated could not allow for the development of water quality monographs for all organic contaminants of concern but for a few selected contaminants whose information was inadequate to allow for decision-making. </li> <li>The determination of concentration levels of organic contaminants in fish, sediment and water samples could have been limited by the failure of current analytical instruments to go down to lower levels at which they occur in the drinking water value chain. <l/i> <li>Only two events could be planned, during the wet season (high flow) and dry season (low flow) based on time and budget constraints. </li> <li>Although various experts were consulted and invited to attend workshops in order to validate the process, the attendance could not be extended to all nine provinces given the time and budget constraints. <br></li></ul> Based on the above, recommendations were made for the dissemination and use of the products emanating from this study. For example, it is recommended that the current protocol be made available to water utilities and the process of revising the current priority list be repeated every 5 years. Further research should be conducted to obtain full coverage of organic contaminants impacting on source water quality in all ground water and surface water systems used as sources for drinking water production. Another major recommendation is the investigation of potential analytical methods that current chromatographic methods with high resolution mass spectrometry to ensure that organic contaminants can be detected at the ng/l to pg/l using a single enrichment method in order to make sure that those organic contaminants that occur at very low concentration in environmental samples can be detected. For example, the realisation that compounds such as synthetic organic polymer residues, emerging disinfectant by-products, detergent metabolites, chlorinated benzenes, alkyl phenol, polyethoxylates, their metabolites and cyanotoxins are continuously discharged into the environment via wastewater and industrial effluent discharges which increases their concentration in aquatic environment and concomitantly their potential to exert adverse health effects in water used as source for the production of drinking water necessitates that each of these groups be added to the current monitoring programme. The current water quality monographs can be used for the benefit of the Drinking Water industry. It is also recommended that a training manual on the production and use of water quality monographs is produced to facilitate their dissemination. CD-ROMs on the water quality monographs can be produced and distributed with the manual. / Thesis (PhD)--University of Pretoria, 2010. / School of Health Systems and Public Health (SHSPH) / PhD / Unrestricted

Nanofiltration (NF) is an attractive option for the treatment of wastewater e.g. municipal wastewater and landfill leachate. However, membrane fouling can be a major obstacle in the implementation of this technology. Fouling of nanofiltration membranes by hu-mic acids (HA) was investigated using bisphenol A (BPA) as an indicator chemical to dif-ferentiate between various mechanisms that may lead to a change in solute rejection. Three commercially available NF membranes were investigated and an accelerated foul-ing condition was achieved with a foulant mixture containing humic acids in an electro-lyte matrix. The effects of membrane fouling on the rejection of BPA were interpreted with respect to the membrane pore sizes and the fouling characteristics. Results report-ed here indicate that calcium concentration in the feed solution could be a major factor governing the humic acid fouling process. Moreover, a critical concentration of calcium in the feed solution was observed, at which membrane fouling was most severe. Mem-brane fouling characteristics were observed by their influence on BPA rejection. Such influence could result in either an increase or decrease in rejection of BPA by the three different membranes depending on the rejection mechanisms involved. It is hypothe-sised that these mechanisms could occur simultaneously and that the effects of each might not be easily distinguished. However, it was observed that their relative contribu-tion was largely dependent upon membrane pore size. Pore blocking, which resulted in a considerable improvement in rejection, was prominent for the more open pore size TFC-SR2 membrane. In contrast, the cake-enhanced concentration polarisation (CECP) effect was more severe for the tighter NF270 and NF90 membranes. For hydrophobic solutes such as BPA, the formation of the fouling layer could also interfere with the so-lute-membrane interaction, and therefore, exert considerable influence on the separa-tion process. The combined impact of humic acid fouling and CaCO3 scaling on the rejection of trace organic contaminants by a commercially available nanofiltration membrane was inves-tigated in this study. Due to the presence of humic acid in the feed solution, CaCO3 scal-ing behaviour differed substantially from that of a pure CaCO3 solution. A prolonged induction period was consistently observed prior to the onset of membrane scaling. In addition, membrane scaling following humic acid fouling did not result in a complete loss of permeate flux. This is consistent with the absence of any large CaCO3 crystals. In fact, the CaCO3 crystals on the membrane surface were quite small and similar in size, which would result in a relatively porous cake layer. At the onset of CaCO3 scaling the rejection of all three trace organic contaminants started to decrease dramatically. The observed decrease in rejection of the trace organic contaminants was much more se-vere than that reported previously with a single layer of either organic or colloidal foul-ing. Such severe decrease in rejection can be attributed to the extended cake-enhanced concentration polarisation effect occurring as a result of the combination of membrane fouling and scaling. The porous CaCO3 scaling layer could lead to a substantial cake-enhanced concentration polarisation effect. In addition, the top CaCO3 scaling layer could reduce the wall shear rate within the underlying humic acid fouling layer, causing an additional concentration polarisation (CP) effect.:1 INTRODUCTION 1 1.1 Fundamentals of NF/RO 1 1.1.1 Solute transport through NF/RO membranes 2 1.1.2 Separation mechanisms 3 1.1.2.1 Steric size exclusion 3 1.1.2.2 Donnan effect 3 1.1.2.3 Electrostatic repulsion 4 1.1.2.4 Adsorption 4 1.1.3 Environmental applications of NF/RO 5 1.1.4 Drinking water treatment from groundwater and surface water sources 5 1.1.5 Water/Wastewater reclamation 7 1.2 Classification and materials of NF/RO membranes 7 1.2.1 Membrane classes 7 1.2.2 Membrane materials 8 1.2.3 Organic membrane materials 9 1.2.3.1 Polyamide membranes 9 1.2.3.2 Cellulose acetate membranes 9 1.2.4 Inorganic membrane materials 10 1.3 Removal of trace organic contaminants 11 1.3.1 Impact of membrane characteristics 14 1.3.1.1 Molecular weight cut-off/pore size 14 1.3.1.2 Surface charge 14 1.3.1.3 Hydrophobicity/hydrophilicity 15 1.3.1.4 Surface morphology 15 1.3.2 Impact of feed characteristics 17 1.3.2.1 pH value 17 1.3.2.2 Ionic strength 18 1.3.2.3 Organic matter 19 1.3.2.4 Presence of divalent ions 20 1.3.2.5 Presence of foulants 20 1.3.2.6 Temperature 20 1.3.3 Impact of solute characteristics 22 1.3.3.1 Molecular weight 22 1.3.3.2 Molecular size (length and width)/molecular volume 22 1.3.3.3 Minimum projection area/Equivalent width 23 1.3.3.4 Charge 23 1.3.3.5 Hydrophobicity/hydrophilicity 24 1.3.4 Impact of operational characteristics 25 1.3.4.1 Transmembrane pressure/permeate or transmembrane flux 25 1.3.4.2 Cross-flow velocity/recovery/concentration polarisation 25 1.3.5 Impact of fouling on rejection 26 1.3.5.1 Organic fouling 28 1.3.5.2 Colloidal fouling 30 1.3.5.3 Inorganic fouling (scaling) 31 1.3.5.4 Biological fouling 32 1.3.6 Impact of membrane cleaning on rejection 32 1.3.6.1 Changes of membrane morphology due to cleaning 32 1.3.6.2 Impact on rejection of TrOCs due to cleaning 33 1.3.7 Validation at pilot and full scale systems 35 2 MEMBRANE FOULING IN THE NANOFILTRATION OF LANDFILL LEACHATE AND ITS IMPACT ON TRACE CONTAMINANT REMOVAL 37 2.1 Introduction 37 2.2 Materials and Methods 40 2.2.1 Analytical reagents and chemicals 40 2.2.2 Nanofiltration membrane 40 2.2.3 Membrane filtration set-up and protocol 41 2.2.4 Analytical technique 42 2.3 Results and discussion 42 2.3.1 Landfill leachate characterisation 42 2.3.2 Physico-chemical properties of bisphenol A 43 2.3.3 Influence of the calcium concentration on the flux 44 2.3.4 Influence of fouling on the rejection of organic contaminants 46 2.4 Conclusions 48 3 CHARACTERISING HUMIC ACID FOULING OF NANOFILTRATION MEMBRANES USING BISPHENOL A AS A MOLECULAR INDICATOR 50 3.1 Introduction 50 3.2 Materials and methods 52 3.2.1 Model NF membranes and membrane characterisation 52 3.2.2 Model trace organic contaminant 52 3.2.3 Organic foulant 53 3.2.4 Membrane filtration set-up 54 3.2.5 Filtration protocol 55 3.2.6 Analytical technique 56 3.3 Results and discussions 56 3.3.1 Membrane characteristics 56 3.3.2 Membrane fouling behaviour 58 3.3.3 Change of membrane hydrophobicity 61 3.3.4 Effects of organic fouling on the nanofiltration of BPA 63 3.3.5 Effects of organic fouling on rejection: the mechanisms 65 3.4 Conclusions 67 4 EFFECTS OF FOULING AND SCALING ON THE REJECTION OF TRACE ORGANIC CONTAMINANTS BY A NANOFILTRATION MEMBRANE: THE ROLE OF CAKE-ENHANCED CONCENTRATION POLARISATION 69 4.1 Introduction 69 4.2 Materials and methods 71 4.2.1 Nanofiltration membrane 71 4.2.2 Chemicals and reagents 71 4.2.3 Crossflow membrane filtration system 72 4.2.4 Experimental protocol 73 4.2.5 SEM-EDS analysis 74 4.2.6 Analytical methods 75 4.3 Results and discussion 75 4.3.1 Membrane characteristics 75 4.3.2 Membrane fouling and scaling development 76 4.3.3 Effects of fouling/scaling on the membrane rejection behaviour 79 4.3.4 Cake-enhanced concentration polarisation 85 4.4 Conclusions 87 5 SUMMARY AND CONCLUSIONS 88 6 REFERENCES 94 7 ACKNOWLEDGEMENTS 112

Organic contaminants from industrial and/or domestic effluents may be harmful to humans directly or indirectly by degrading the quality of the aquatic environment. Consequently these contaminants must be reduced to levels that are not harmful to humans and the environment before disposal. Chemical, physical and biological methods exist for the removal of these pollutants from effluents. Among the available chemical methods, heterogeneous photocatalytic oxidation has been found particularly effective in removing a large number of persistent organics in water. In this study, photocatalytic degradation was explored for the removal of reactive azo-dye (textile dye), triclocarban (disinfectant), clopyralid (herbicide) and three endocrine disrupting compounds (EDCs) (estrone, 17ß-estradiol and 17α-ethinylestradiol) from synthetic effluents. The major factors affecting the photocatalytic processes including the initial concentration of the target compounds, the amount of catalyst, the light intensity, the type of catalyst, the electron acceptor, the irradiation time and the pH were studied. Other oxidation techniques including (O3, H2O2, UV) were also studied. Generally UV light is used in combination with titanium dioxide, as photocatalyst, to generate photoinduced charge separation leading to the creation of electron-hole pairs. The holes act as electron acceptors hence the oxidation of organics occur at these sites. These holes can also lead to the formation of hydroxyl radicals which are also effective oxidants capable of degrading the organics. The results obtained in this study indicated that photolysis (i.e. UV only) was found to have no effect on the degradation of reactive azo-dye (RO16). However, complete photocatalytic degradation of 20 mg/L (3.24×10-2 mM) RO16 was achieved in 20 minutes in the presence of 1g/L TiO2 Degussa P25 at pH 5.5. Comparison between various types of catalysts (i.e. Degussa P25, VP Aeroperl, Hombifine N) gave varied results but Degussa P25 was the most effective photocatalyst hence it was selected for this study. For RO16 the optimum catalyst concentration was 0.5 g/L TiO2 with initial concentration of 20 mg/L RO16. It was found that the disappearance of RO16 satisfactorily followed the pseudo first-order kinetics according to Langmuir-Hinshelwood (L-H) model. The rate constant was k= 0.0928 mol/min. Photodegradation of TCC was studied in 70%v acetonitrile: 30%v water solutions. UV light degraded TCC effectively and the reaction rates increased with decreasing initial concentration of TCC. UV/TiO2 gave unsatisfactory degradation of triclocarban (TCC) since only 36% were removed in 60 minutes with initial concentration of TCC 20 mg/L. The degradation of clopyralid and the EDCs was studied using three oxidation systems UV/TiO2, UV/H2O2 and O3. Complete degradation of clopyralid (3,6-DCP) was achieved with UV/TiO2 in about 90 minutes at an optimum catalyst concentration of 1g/L. Zero-order kinetics was found to describe the first stage of the photocatalytic reaction in the concentration range 0.078-0.521 mM. At pH 5 the rate constant was 2.09×10-6-4.32×10-7 M.s-1.Complete degradation of all the three EDCs was achieved with UV/H2O2 in 60 minutes at catalyst concentration of (2.94×10-2 M). On the other hand complete degradation of the EDCs was achieved in just 2 minutes with ozonation. For high concentration EDCs, TiO2/UV gave low efficiency of degradation as compared with ozone and H2O2/UV. First-order kinetics was found to describe the photocatalytic reaction of the EDCs. / Education Service Department of the Libyan Government

The performance of an aerated horizontal subsurface flow treatment wetland was investigated before, during and after a simulated aeration failure. Conventional wastewater parameters (e.g., carbonaceous biological oxygen demand, total nitrogen, and Escherichia coli) as well as selected micropollutants (caffeine, ibuprofen, naproxen, benzotriazole, diclofenac, acesulfame, and carbamazepine) were investigated. Furthermore, the removal of biological effects was investigated using in vitro bioassays. The six bioassays selected covered environmentally relevant endpoints (indicative of activation of aryl hydrocarbon receptor, AhR; binding to the peroxisome proliferator-activated receptor gamma, PPARγ; activation of estrogen receptor alpha, ERα; activation of glucocorticoid receptor, GR; oxidative stress response, AREc32; combined algae test, CAT). During the aeration interruption phase, the water quality deteriorated to a degree comparable to that of a conventional (non-aerated) horizontal subsurface flow wetland. After the end of the aeration interruption, the analytical and biological parameters investigated recovered at different time periods until their initial treatment performance. Treatment efficacy for conventional parameters was recovered within a few days, but no complete recovery of treatment efficacy could be observed for bioassays AhR, AREc32 and CAT in the 21 days following re-start of the aeration system. Furthermore, the removal efficacy along the flow path for most of the chemicals and bioassays recovered as it was observed in the baseline phase. Only for the activation of AhR and AREc32 there was a shift of the internal treatment profile from 12.5% to 25% (AhR) and 50% (AREc32) of the fractional length.

Organic contaminants from industrial and/or domestic effluents may be harmful to humans directly or indirectly by degrading the quality of the aquatic environment. Consequently these contaminants must be reduced to levels that are not harmful to humans and the environment before disposal. Chemical, physical and biological methods exist for the removal of these pollutants from effluents. Among the available chemical methods, heterogeneous photocatalytic oxidation has been found particularly effective in removing a large number of persistent organics in water. In this study, photocatalytic degradation was explored for the removal of reactive azo-dye (textile dye), triclocarban (disinfectant), clopyralid (herbicide) and three endocrine disrupting compounds (EDCs) (estrone, 17ß-estradiol and 17α-ethinylestradiol) from synthetic effluents. The major factors affecting the photocatalytic processes including the initial concentration of the target compounds, the amount of catalyst, the light intensity, the type of catalyst, the electron acceptor, the irradiation time and the pH were studied. Other oxidation techniques including (O3, H2O2, UV) were also studied. Generally UV light is used in combination with titanium dioxide, as photocatalyst, to generate photoinduced charge separation leading to the creation of electron-hole pairs. The holes act as electron acceptors hence the oxidation of organics occur at these sites. These holes can also lead to the formation of hydroxyl radicals which are also effective oxidants capable of degrading the organics. The results obtained in this study indicated that photolysis (i.e. UV only) was found to have no effect on the degradation of reactive azo-dye (RO16). However, complete photocatalytic degradation of 20 mg/L (3.24×10-2 mM) RO16 was achieved in 20 minutes in the presence of 1g/L TiO2 Degussa P25 at pH 5.5. Comparison between various types of catalysts (i.e. Degussa P25, VP Aeroperl, Hombifine N) gave varied results but Degussa P25 was the most effective photocatalyst hence it was selected for this study. For RO16 the optimum catalyst concentration was 0.5 g/L TiO2 with initial concentration of 20 mg/L RO16. It was found that the disappearance of RO16 satisfactorily followed the pseudo first-order kinetics according to Langmuir-Hinshelwood (L-H) model. The rate constant was k= 0.0928 mol/min. Photodegradation of TCC was studied in 70%v acetonitrile: 30%v water solutions. UV light degraded TCC effectively and the reaction rates increased with decreasing initial concentration of TCC. UV/TiO2 gave unsatisfactory degradation of triclocarban (TCC) since only 36% were removed in 60 minutes with initial concentration of TCC 20 mg/L. The degradation of clopyralid and the EDCs was studied using three oxidation systems UV/TiO2, UV/H2O2 and O3. Complete degradation of clopyralid (3,6-DCP) was achieved with UV/TiO2 in about 90 minutes at an optimum catalyst concentration of 1g/L. Zero-order kinetics was found to describe the first stage of the photocatalytic reaction in the concentration range 0.078-0.521 mM. At pH 5 the rate constant was 2.09×10⁻⁶ ± 4.32×10⁻⁷ M.s⁻¹. Complete degradation of all the three EDCs was achieved with UV/H₂O₂ in 60 minutes at catalyst concentration of (2.94×10⁻² M). On the other hand complete degradation of the EDCs was achieved in just 2 minutes with ozonation. For high concentration EDCs, TiO₂/UV gave low efficiency of degradation as compared with ozone and H2O2/UV. First-order kinetics was found to describe the photocatalytic reaction of the EDCs.