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In this paper, we report the study of essential oils adsorption on three phosphate fertilizers: monoammonium phosphate (MAP), diammonium phosphate (DAP) and triple superphosphate (TSP), with the aim to prepare a bifunctional product which can be used as a fertilizer and biopesticide. Essential oils were isolated by steam distillation from Eucalyptus salubris and Artemisia herbaalba and analysed by GC-MS and GC-FID. About 12 and 22 constituents were identified and quantified in these oils, respectively. The kinetic adsorption study of essential oils showed that DAP and TSP exhibited high adsorption capacities compared with MAP (DAP (0.143 g/g) and TSP (0.139 g/g) for E. salubris essential oil and (DAP (0.135 g/g) and TSP (0.134 g/g) for A. herba- -alba essential oil). The adsorption isotherms of all identified components in the E. salubris essential oil were determined and the Langmuir and Freundlich models were used to describe the experimental data. Langmuir model fitted well the isotherms of the majority of the essential oil components (1,8-cineole, α-pinene, β-pinene, isopinocarveol, β-eudesmol, α-phellandrene, pinocarvone, p-cymene and spathulenol) and only terpineol and globulol isotherm data followed the Freundlich model. The selectivity was affected by the abundance of each component in the crude essential oil and the polarity of terpenic components.

In this study, the removal of bromate, a regulated ozone by-product, was evaluated using a strong-base anion (SBA) exchange resin in batch and column experiments. The kinetics studies in batch mode showed that film diffusion-controlled bromate exchange in SBA and the isotherm studies showed that the Langmuir model fitted the experimental results with a maximum exchange capacity of 296.66 mg BrO3−/g (~1.3 meq/mL resin). In the fixed-bed column studies, breakthrough curves were obtained under different operating conditions to examine the effects of feed flow rate, inlet bromate concentration, and bed height on column performance. A modified n-order Bohart and Adams model (n-BAM-c), which considered the asymmetry of the breakthrough curve and flow channeling, was applied for the first time to describe the experimental data obtained from the column and to predict the breakthrough curves. It was found that n-BAM-c fitted the experimental data well (R2 > 0.99) and the effects of the key operating conditions on the model parameters were determined. Overall, the results show that SBA exchange is suitable for bromate removal from water and n-BAM-c could be a powerful tool for the design and upscaling of bromate ion exchange columns. [ABSTRACT FROM AUTHOR]

The Institute of Environmental Management and Assessment (IEMA) Associate Certificate in Environmental Management course is designed to raise the professional competence of aspiring and existing environmental practitioners. Successful completion entitles the individual to become an associate IEMA member. A dedicated evaluation model was developed for this focused research, in order to determine the factors which influence student attendance and success on the course. The methodology utilised the core elements of three academically proven training evaluation models to examine presage and process factors, the student's reaction to the course, and changes in knowledge, attitude and understanding. A range of personal, work-related and course-related factors were identified. These include student motivation, previous environmental experience and preferred learning style. A negative correlation was found between examination success and the need for students to also focus on work activities while attending this course. (Contains 2 figures and 5 tables.)

The discovery of antibiotics, which was once regarded as a timely medical intervention now leaves a bitter aftertaste: antimicrobial resistance (AMR), due to the unregulated use of these compounds and the poor management receiving wastewaters before discharge into pristine environments or the recycling of such treated waters. Wastewater treatment plants (WWTPs) have been regarded a central sink for the mostly unmetabolized or partially metabolised antibiotics and is also pivotal to the incidence of antibiotic resistance bacteria (ARBs) and their resistance genes (ARGs), which consistently contribute to the global disease burden and deteriorating prophylaxis. In this regard, we highlighted WWTP-antibiotics consumption-ARBs-ARGs nexus, which might be critical to understanding the epidemiology of AMR and also guide the precise prevention and remediation of such occurrences. We also discovered the unsophistication of conventional WWTPs and treatment techniques for adequate treatment of antibiotics, ARBs and ARGs, due to their lack of compliance with environmental sustainability, then ultimately assessed the prospects of cold atmospheric plasma (CAP). Herein, we observed that CAP technologies not only has the capability to disinfect wastewater polluted with copious amounts of chemicals and biologicals, but also have a potential to augment bioelectricity generation, when integrated into bio electrochemical modules, which future WWTPs should be retrofitted to accommodate. Therefore, further research should be conducted to unveil more of the unknowns, which only a snippet has been highlighted in this study. [ABSTRACT FROM AUTHOR]

COVID-19 pandemic has created chaos in almost every walk of life. The harsh impact of the disease is mainly rooted to the rapid and easy spread of SARS-CoV-2 virus through airborne and fomite routes. Thus, disinfection of contaminated surfaces and air is important to hamper COVID-19 disease transmission. Ozone being a potent gaseous disinfectant has been utilized to inactivate a wide-range of viruses and has more recently gained interest in the inactivation of SARS-CoV-2. This article critically reviews the current state-of-knowledge on disinfection of surface-adhered and airborne SARS-CoV-2 by ozone. The transmission and survival characteristics of SARS-CoV-2 alongside the specificity of ozone inactivation process are reviewed. Distinct focus is then given to reviewing the status of ozone inactivation of surface-adhered and airborne SARS-CoV-2 in terms of experimental investigations, kinetics, and influence of the operational factors on the inactivation process. Ozone inactivation of SARS-CoV-2 is compared to other enveloped viruses, and the challenges and future prospects of ozone inactivation of SARS-CoV-2 are also addressed. [ABSTRACT FROM AUTHOR]

The fourth issue of Ozone: Science and Engineering focuses on the treatment of contaminated waters using ozone and advanced oxidation processes (AOPs). The International Ozone Association has addressed various water challenges, including the treatment of recalcitrant and emerging contaminants, and water reuse applications. This issue includes papers on topics such as the efficiency of ozone treatment without hydrogen peroxide, the use of AOPs for textile dye treatment, a nickel-based catalyst for ozonation of tartrazine wastewater, pharmaceutical removal by ozonation combined with adsorption, improving ozone generation, the use of chitosan-coated nanoemulsions of ozonated olive oil for treating leishmaniasis, and the use of ozone gas for controlling microbial and fungal growth in cheese ripening. The authors hope that this issue will inspire new research ideas in the ozone field to address environmental and human health challenges. [Extracted from the article]

This study developed a prototype of a wire-plate air bubbling plasma reactor that can be easily scaled up for wastewater treatment. The electrical characteristics, including the discharge current and average power consumed, of the developed reactor were deeply investigated at different operating parameters and solution conductivities. The performance of the reactor was examined on the basis of energy efficiency and methylene blue (MB) decoloration efficiency. Moreover, the removal of the total organic carbon and the changes of the physicochemical properties of solution, including pH, conductivity, and temperature, were evaluated. The analysis of current discharge and average power consumed showed that the discharge mode in the present reactor is a filamentary streamer. Interestingly, the solution conductivity had no effect on the average power consumed at low applied voltages, due to confinement of the discharge in a small area surrounding the discharge electrode in the gas phase. However, at relatively high voltages, the effect of conductivity on the average power consumed was noticeable, yet it had no effect on the decoloration efficiency at the same average power. The present reactor showed a high energy-efficiency value of 42 g/kWh at 50% decoloration of 30 mg/l MB solution, but it dropped to 14 g/kWh at 97% decoloration. A first-order kinetics model described well the decoloration reaction rates and the overall rate constant correlated linearly to the average power. [ABSTRACT FROM AUTHOR]

This study developed a prototype of a wire-plate air bubbling plasma reactor that can be easily scaled up for wastewater treatment. The electrical characteristics, including the discharge current and average power consumed, of the developed reactor were deeply investigated at different operating parameters and solution conductivities. The performance of the reactor was examined on the basis of energy efficiency and methylene blue (MB) decoloration efficiency. Moreover, the removal of the total organic carbon and the changes of the physicochemical properties of solution, including pH, conductivity, and temperature, were evaluated. The analysis of current discharge and average power consumed showed that the discharge mode in the present reactor is a filamentary streamer. Interestingly, the solution conductivity had no effect on the average power consumed at low applied voltages, due to confinement of the discharge in a small area surrounding the discharge electrode in the gas phase. However, at relatively high voltages, the effect of conductivity on the average power consumed was noticeable, yet it had no effect on the decoloration efficiency at the same average power. The present reactor showed a high energy-efficiency value of 42 g/kWh at 50% decoloration of 30 mg/l MB solution, but it dropped to 14 g/kWh at 97% decoloration. A first-order kinetics model described well the decoloration reaction rates and the overall rate constant correlated linearly to the average power. [ABSTRACT FROM AUTHOR]

In this research, the removal of the pesticide chlorpyriphos (CPE) from water by adsorption using a novel adsorbent made of γ-Fe2O3/Al-ZnO nanocomposite was studied. The adsorbent was characterized using Fourier-transformed infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) surface area, and vibrating sample magnetometry (VSM). The main parameters affecting the adsorption process, including the initial pH (2–12), the concentration of pesticide (10–70 ppm), the %Fe2O3 of the adsorbent, and the adsorption time (≤60 min), were studied. The results demonstrated that the adsorption of CPE depended on the pH, with a maximum removal of 92.3% achieved at around neutral pH. The adsorption isotherm was modelled and the results showed that the Freundlich model fitted the experimental data better than the Langmuir and Temkin models. The kinetics of adsorption were also studied and modelled using the pseudo-first-order and pseudo-second-order models, with the former being found more suitable. Energy dispersive X-ray (EDX) analysis confirmed the adsorption of CPE on γ-Fe2O3/Al-ZnO, while FTIR analysis suggested that the hydroxyl, N-pyridine, and chloro functional groups governed the adsorption mechanism. Furthermore, VSM analysis revealed that the magnetization saturation of γ-Fe2O3/Al-ZnO nanocomposite, after CPE adsorption, was slightly lower than that of fresh γ-Fe2O3/Al-ZnO but remained adequate for the efficient separation of the adsorbent simply using a magnet. This study demonstrates that binary γ-Fe2O3/Al-ZnO magnetic nanocomposites are effective for the removal of chlorpyriphos and could be highly promising materials for the removal of emerging pollutants in wastewater. [ABSTRACT FROM AUTHOR]

BACKGROUND: Water contaminated by heavy metals has many negative impacts on human health and the environment. According to the UN's sustainable development goals, preserving natural resources will have positive impacts on living conditions by reducing diseases. In this study, a novel adsorbent synthesized from phosphate‐based geopolymer cement composite material was developed and evaluated for lead removal from aqueous solutions. The developed adsorbent is made from natural resources using a facile protocol, and thus it is suitable for both developed and developing countries. RESULTS: Analyses of mineralogical composition, pore‐size distribution and surface of the synthesized phosphate‐based geopolymer cement composite were performed. A microporous structure was observed from the microstructural characterization. Geopolymer cement was immobilized with sodium alginate to fabricate alginate–geopolymer cement beads (Alg/GES). The parameters influencing the adsorption process were investigated in batch mode. The obtained results showed that the adsorption capacity of Pb(II) ions increased with time and equilibrium was reached in 90 min. The optimum adsorption pH was 4.17. The experimental results showed that the adsorption equilibrium of Pb(II) on Alg/GES was well described by the Freundlich and Langmuir models whereas the adsorption rate was well fitted by the pseudo‐second‐order kinetics model. The maximum adsorption capacity obtained from the Langmuir isotherm was qmax = 0.38 mmol g−1. From the Dubinin–Radushkevitch isotherm model, the value of the free adsorption energy was 41 kJ mol−1. CONCLUSIONS: Compared with other adsorbents, Alg/GES exhibited a greater adsorption capacity confirming that the phosphate‐based geopolymer cement can be suitable for removal of heavy metals from wastewaters. © 2021 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The article is a welcome letter from the new Editor-in-Chief of the journal Ozone: Science and Engineering. The Editor-in-Chief expresses pride and honor in taking over the role from the outgoing Editor-in-Chief, who led the journal for 25 years. The journal, which was established in the 1970s by the International Ozone Association, publishes research on a wide range of ozone-related topics. The Editor-in-Chief emphasizes the importance of rigorous research methodologies and validated techniques for ozone measurements. They also highlight the significance of peer review in ensuring the publication of high-quality research. The journal aims to take advantage of new models and tools of publication to reach a wider audience and increase its visibility. The Editor-in-Chief expresses gratitude to authors and reviewers and invites researchers to submit their work to the journal. They also mention the Harvey M. Rosen Memorial Award, which recognizes the best paper published in the journal every two years. The article concludes with an invitation for those with expertise in ozone and oxidation to join the journal's Editorial Board. [Extracted from the article]

Currently, no medicine has demonstrated efficacy in treating the ongoing pandemic COVID-19 caused by SARS-CoV-2 virus. Being a potent oxidant, ozone is lethal against most bacteria and viruses found in water, or on surfaces and aerosols. Ozone has also been successfully used to treat several viral diseases such as Ebola and HIV Hepatitis B and C. Using molecular modeling, this study evaluated the reactivity of ozone toward representative key molecules in the structure of SARS-CoV-2. The results show that ozone is able to attack the proteins and lipids of the virus's spikes and envelope, particularly the amino acids tryptophan, methionine and cysteine, and the fatty acids, arachidonic acid, linoleic acid, and oleic acid. Ozone also attacks the N-glycopeptides of the spike protein subunits 1 and 2, though at lower reactivity. Disruption of the structure of SARS-CoV-2 could inactivate the virus, suggesting that ozone could be an effective oxidant against COVID-19 virus. If incorrectly applied, ozone is toxic and contact with the respiratory tract must be avoided. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Several AOPs were compared for DEP removal in water. • Oxidation by OH was the prevailing pathway for DEP degradation. • Ozone-based AOPs were the most effective for DEP removal. • O 3 /Al 2 O 3 gave the highest DEP removal. • Reaction products and their kinetics were identified by LC/MS/MS. Abstract Several Advanced Oxidation Processes (AOPs) including O 3 /H 2 O 2 , O 3 /TiO 2 , O 3 /activated carbon (AC), O 3 /Al 2 O 3 , O 3 /Fe2+/H 2 O 2 and UV/TiO 2 have been investigated and compared for the removal of diethyl phthalate (DEP), an endocrine disrupting compound, in aqueous solutions. Hydroxyl radicals were the main species responsible for DEP degradation and this was supported by computational chemistry calculation, scavenger experiments, and LC/MS/MS analysis. The change of the abundance of reaction products over time was determined. Organic acids as well as anhydride and hydroxylated products were found to accumulate in solution even after long reaction time (2 h). Careful choice of the operating parameters (pH, ozone concentration and catalyst dosage) was crucial to achieve enhanced performance of the combined processes above what each oxidant and catalyst can achieve alone. O 3 /AC process was found to reduce the oxidation efficiency of O 3 at high ozone concentrations. Heterogeneous catalytic ozonation with Al 2 O 3 was the most effective process for DEP removal (∼100% removal in about 15 min) and based on pseudo-first-order kinetics at pH7, the studied oxidation processes followed the order: O 3 /Al 2 O 3 (0.093 min−1)>O 3 /H 2 O 2 /Fe2+(0.076 min−1)>O 3 /AC(0.069 min−1)>O 3 /H 2 O 2 (0.053 min−1)>O 3 /TiO 2 (0.050 min−1)> O 3 alone (0.039 min−1)>UV/TiO 2 (0.009 min−1). [ABSTRACT FROM AUTHOR]

This research demonstrates for the first time that ozone is an effective cleaning agent for polyvinylidene fluoride (PVDF) membranes fouled by natural organic matter (NOM). Bare PVDF membranes as well as PVDF impregnated with CNTs (pristine (CNTs–P) and oxidized (CNTs–O)) at 0.3% mass membranes were used. Three different methods were investigated for cleaning the fouled membranes including; A: 10-min cleaning by pure water, B: 5-min water followed by 5-min ozonated water, and C: 10-min fully ozonated water. It was found that the application of fully ozonated water for 10 min was very effective to reinstate the flux to almost its original value of unfouled membrane. The CNTs–P/PVDF membrane exhibited the highest fouling with a total fouling ratio of 81%, while for the bare PVDF and the CNTs–O/PVDF membranes, the fouling ratios were 76% and 74%, respectively. The full ozonated water cleaning method gave the highest removal of fouling leaving the lowest irreversible fouling on the membrane as compared to the other cleaning methods. On the other hand, the highest removal of NOM fouling was obtained for CNTs–O/PVDF membranes indicating that fouling on CNTs–O/PVDF membrane was less bound than the other membranes. Contact angle measurements of the fouled membranes showed that all membranes exhibited increased contact angles due to the NOM deposition but after cleaning, particularly with ozonated water, the membrane contact angles returned to almost their original values. FTIR analysis of the membranes corroborated the results obtained. [ABSTRACT FROM PUBLISHER]

The popularity of membrane technology in water treatment has been rising for over last 50 years due to wide range of filtration processes and applications, cost effective production and installation as well as safe and efficient water production. However, the development and improvement of membranes is ongoing due to number of weaknesses. Membrane fouling is a major drawback of membrane application in water and waste water treatment. Mostly caused by natural organic matter (NOM), fouling forms a layer on top of the membrane and blocks pores reducing the water permeation and can be potentially destructive to the membrane structure. The issue of membrane fouling can be addressed during membrane manufacturing, maintenance and operation. In the current study, the graphene-based nanomaterials (GBN) were incorporated in polyvinylidene fluoride (PVDF) to manufacture membranes via the phase-inversion technique. The resulting membranes show significant improvement to the properties of the pure PVDF membranes and their antifouling ability. The addition of GBN enhanced the water permeation by over 79% as a result of increased membrane hydrophilicity. Although this enhancement is beneficial, membrane fouling remained an issue despite the observed improvement. In this study, ozone, which is an effective oxidant, was evaluated as a novel technique for the cleaning of humic acid-fouled membranes. When ozone cleaning was applied to the humic acid-fouled membranes, reestablishment of close to original flux values was observed after just 30 min of cleaning. This statement is supported by SEM images that give an insight into the fouling of the membrane surface after the application of the cleaning methods. The data indicate that ozone is an effective technique for membrane cleaning against NOM-induced fouling. [ABSTRACT FROM PUBLISHER]

Ozonation has been proven effective for the removal of endocrine disrupting chemicals (EDCs) in water. However, conventional ozonation processes are still limited by ozone low solubility and stability in water. These limitations may be overcome by mixing a prior ozone-loaded non-polar solvent with the aqueous solution. This two-phase ozonation process combines Liquid-liquid extraction and Ozonation (LLO). Decamethylcyclopentasiloxane (D5) was chosen as the solvent to be charged with ozone for its non-toxicity, reusability and high ozone solubility. A concurrent LLO column reactor was designed for the simultaneous degradation of three endocrine disrupting chemicals (EDCs) in water: Estrone (E1), 17β-estradiol (E2) and 17α-estradiol (EE2). Results showed that 98% of EDCs were removed effectively from a solution initially concentrated at 1 mg L−1. The efficacy of the degradation depends essentially of the column feeding flowrate, the ozone dose and the operating pH. The generation of by-products during EDCs degradation by LLO was also investigated in this study. For a complete removal of both EDCs and by-products, the dose of ozone had to be doubled. [ABSTRACT FROM AUTHOR]

Multiwalled carbon nanotubes functionalized by plasma oxygen (CNTs) have been used as heterogeneous catalysts for the ozonation of methyl orange (MO) dye (CI 13025) in aqueous solutions. It was found that the addition of CNTs significantly enhanced the dye decolorization as compared to ozone alone or when activated carbon was used at the same dose as CNTs. Both the initial ozone concentration and catalyst dosage enhanced the removal of MO. However, ozone gas concentrations higher than 6 g/m3NTP did not further improve the decolorization rates. The removal efficiency of MO increased with pH in the range 2 to 3, while a reverse trend was observed when the pH increased from 3 to 9. The addition of a radical scavenger resulted in only a limited change in the decolorization rates suggesting that molecular ozone was the main pathway by which MO decolorization occurred in solution. However, under favorable conditions for MO attraction to CNT surface (pH = 3), the decolorization rate has significantly increased. At higher pH than the pKa value of MO (3.47) and the point of zero charge of CNT (3.87), a condition that favors the electrostatic repulsion of MO from CNT, the rates were reduced in the presence of CNT as compared to ozone alone possibly due to loss of part of the supplied ozone in un-useful parallel reactions. [ABSTRACT FROM PUBLISHER]

Removal of heavy metals, such as copper ions, from water is important to protect human health and the environment. In this study, manganese coated sand (MCS) was used as an adsorbent to remove copper ions in a batch system. Equilibrium data were determined at a temperature of 25.6 °C and the Langmuir model was used to describe the experimental data. Mn-coating improved the removal of copper ions by 70% as compared to uncoated sand. Based on a kinetics study, the adsorption of copper ions on MCS was found to occur through a chemisorption process and the pseudo-second-order model was found to fit the kinetics experimental data well. Due to particle interactions, the equilibrium uptake was reduced as the ratio of sand to volume of solution increased. pH affected the removal of copper ions with lowest uptakes found at pH 3 and pHs >7, whilst at pHs in the range of 4 to 7, the uptake was highest and almost constant at the value of 0.0179 mg/g ± 4%. This study has also revealed that copper ions removal was dissolved oxygen (DO) dependent with the highest removal occurring at ambient DO concentration, which suggests that DO should be carefully studied when dealing with copper ions adsorption. [ABSTRACT FROM AUTHOR]

While antimony has been reported to migrate from PET bottles into contents, reports on bottled water and soft drinks usage and PET bottle reuse patterns are currently unavailable in the literature. Bottle use conditions and patterns are important determinants of antimony migration. In this work a survey assessing the pattern of bottle use and reuse in Britain and Nigeria was undertaken. The survey findings influenced the design of laboratory experiments that assessed the migration of antimony from PET bottles into water and soft drinks. Typical storage durations for bottled contents between purchase and opening for use were 7 days or less. However storage of up to one year was reported. Bottle reuse was high and similar for the two countries with reuse durations being higher in Nigeria. The antimony concentration in 32 PET bottle materials from Britain and Nigeria were similar and ranged between 177 and 310 mg kg−1. For 47 freshly purchased British bottled contents antimony concentration ranged between 0.03 and 6.61 μg L−1 with only one sample exceeding the EU acceptable limit. Concentrations of Cd, Ge, Zn, Al, Be, Ti, Co and Pb were also measured. At realistic temperatures of 40 and 60 °C antimony concentration in deionised water in bottles remained below the EU acceptable limit even after 48 h exposure. The limit was exceeded for most exposures at 80 °C. Concentration of antimony in some bottled contents exceeded the EU limit after 11 months of storage at room temperature. Bottle aging and increase in bottle volume were associated with decreased migration of antimony from bottles. [ABSTRACT FROM AUTHOR]

Abstract: Diboron trioxide/titanium dioxide (B2O3/TiO2) was synthesised at the nano-size and used to remove Cu(II) from water by adsorption. The material was characterised using a number of techniques including XRD, SEM, TEM, and BET surface area. Sizes of the material were below 50nm, which fall within the range of that of nanoparticles. The BET surface area was 222.4±6.8 m2/g. B2O3/TiO2 was effective in removing copper and the maximum adsorption capacity was 82.0mg/g. The equilibrium adsorption data were best fitted to Freundlich model and the adsorption kinetics was well explained by pseudo-second-order kinetic model, which suggests that the copper uptake is due to a chemisorption process. An intraparticle diffusion based Weber–Morris model was applied to evaluate the rate-limiting steps, and the results suggested that pore diffusion controlled the overall sorption process. [Copyright &y& Elsevier]

Abstract: Clopyralid is a herbicide that has recently been reported to occur in drinking water at concentrations above the Permitted Concentration Value (PCV) of 0.1μg/L for an individual pesticide (EU directive 98/83/EC). An extensive laboratory study on clopyralid removal with UV/TiO2, was carried out and was compared to UV/H2O2 and O3 removal efficiencies. The effectiveness of three TiO2 photocatalysts (Degussa P25, VP Aeroperl, Hombifine N) was studied and Degussa P25 was selected since it outperformed the other two. Complete removal of clopyralid was achieved with UV/TiO2 in about 90min at an optimum catalyst concentration of 1g/L. Pseudo-zero-order kinetics were suitable to describe the first stage of the photocatalytic reaction in the concentration range 0.078–0.521mM. pH was found to significantly affect the removal rates of clopyralid due to changes in TiO2 surface charges and clopyralid ionisation degree. The rate constant was maximum at pH 5 and its value was 2.1×10−6 ±4.3×10−7 Mmin−1. Pure oxygen bubbled in solution was found to slightly affect unfavourably the photocatalytic removal of clopyralid as compared to air. With UV/H2O2 and O3 systems, the initial removal rates were high but these systems were not effective in achieving high removal percentages overall. [Copyright &y& Elsevier]

The Institute of Environmental Management and Assessment (IEMA) Associate Certificate in Environmental Management course is designed to raise the professional competence of aspiring and existing environmental practitioners. Successful completion entitles the individual to become an associate IEMA member. A dedicated evaluation model was developed for this focused research, in order to determine the factors which influence student attendance and success on the course. The methodology utilised the core elements of three academically proven training evaluation models to examine presage and process factors, the student's reaction to the course, and changes in knowledge, attitude and understanding. A range of personal, work-related and course-related factors were identified. These include student motivation, previous environmental experience and preferred learning style. A negative correlation was found between examination success and the need for students to also focus on work activities while attending this course. [ABSTRACT FROM AUTHOR]

Diethyl phthalate (DEP) is one of the phthalate esters having wide industrial applications but its occurrence in the aquatic environment has been linked to disruption of the endocrine system. In this study, the removal of DEP with ozone alone (OA) and heterogeneous catalytic ozonation (HCO) with activated carbon (AC) was investigated. Results show that the addi tion of AC was effective to achieve almost 100% degradation of DEP in about 30min using 2.86 g AC/L as compared to over 80min without AC. It was also found that radical reactions were the main mechanism by which DEP was degraded and adsorption contributed significantly to the removal of DEP by OAC. Indeed, after 60min, adsorption alone achieved abou 75% removal, whilst OA achieved 92% removal. In contrast, as expected molecular ozone reactions were relatively insignificant. The contribution of adsorption and radical reactions to the overall removal of DEP were of similar rates at the beginning of the experiments but the latter declined due to competitive reactions. The notable decrease of DEP removal rate observed in the presence of radical scavenger tert-butanol (tb) indicates that the reaction between DEP and ·OH proceeds mainly in the bulk of the aqueous phase. Moreover, the experimental results also revealed that in the absence of tb and after 40min, almost 100% removal was observed as compared to only 64% when tb was added to the solution. This confirms that radical reactions play an important role in DEP removal by the OAC process A model taking into account the various reactions in the bulk solution and on the surface o AC was developed and was found to predict well the experimental data. This study proves that HCO was effective to remove DEP and the changes of the contributory mechanisms underpinning the process were determined as function of time. [ABSTRACT FROM AUTHOR]

Abstract: Membrane retention was investigated with the aid of poly diallydimethylammonium chloride and copolymer of dimethyl aminoethyl acrylate polyelectrolyte coagulants. The membranes used were P005F ultrafiltration (UF) and NF270 nanofiltration (NF) membranes and the studied conditions were salinity level, humic substances (HS) concentration, heavy metals concentration and polyelectrolytes type and concentration. Results showed that with the aid of polyelectrolytes, HS retention reached a maximum point where further increase in polyelectrolytes degraded membrane retention. This study showed also that at low polyelectrolyte concentration, salinity reduced membrane retention. While at optimum polyelectrolytes dose, membrane performance was not affected by salinity. In addition, HS binding capacity for heavy metals was reduced considerably at high salinity levels. [Copyright &y& Elsevier]

There is a growing interest in the possible environmental health impact posed by endocrine-disrupting chemicals (EDCs). A challenge to the field of endocrine disruption is that these substances are diverse and may not appear to share any structural similarity other than usually being low molecular mass (<1000 Da) compounds. Here we demonstrate the effectiveness of sensor device for the detection of low molecular weight, poorly water soluble, estrogenic compounds E1, E2 and EE2, fabricated by electropolymerization over graphene screen printed electrode (SPE). The PANI/Gr-SPE-devices displayed linear responses to estrogenic substances, in EIS assays, from 0.0975 ng/L to 200 ng/L in water samples, with a detection limit of 0.043 pg/L for E1, 0.19 ng/L for E2 and 0.070 pg/L for EE2 which is lower than other current biosensing techniques. This portable, disposable immunosensor offers a solution for immediate measurement at sample collection sites, due to its excellent sensitivity and selectivity when testing water samples obtained directly from rivers and waste water treatment facilities. The simple screen printing production method will enable the low cost, high volume production required for this type of environmental analysis. [ABSTRACT FROM AUTHOR]

In this study, Pb doped ZnO nanoparticles were synthesized by a sol-gel technique for the sorption of Reactive Black 5 (RB5) textile dye in aqueous solution. The ZnO:Pb (2 and 4%) nanoparticles have been characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy and cryogenic nitrogen adsorption method. The average size of the synthesized nanoparticles was less than 100 nm and the surface areas were 18.8 and 20.8 m 2 /g, respectively for ZnO:Pb 2% and ZnO:Pb 4%. Batch sorption experiments were performed for color removal of RB5 dye at ambient temperature and 30 mg/L dye concentration. The central composite design with response surface methodology was used to study the effect of sorption condition (pH, nanoparticles dose and contact time). The significance of independent variables and their interactions was tested by analysis of variance. The optimum conditions of color removal were pH = 7, 2 g/L dose of nanoparticles and a contact time of 79 min. The color removal performance was 79.4 and 98.1% for ZnO:Pb 2 and 4% respectively. The pseudo-second-order model described well the removal rates while the Langmuir model fitted well the adsorption isotherms.

Aloe gel (Alg), which is a natural extract from the Aloe sp. plant, was evaluated in this study for its potential use as a bioflocculant to treat urban wastewater sewage sludge. The gel was used alone and combined with water glass (WG) under controlled conditions in laboratory experiments. Alg was found effective to settle the flocculated sludge rapidly and remove distinctive unpleasant odours of the sludge as highlighted by gas chromatography-mass spectrometry (GC/MS) analysis. Furthermore, Alg was pH tolerant and had no effect in changing the pH of the wastewater. The optimum dose of Alg was 3% at which a sludge volume index (SVI) of 45.4 mL/g was obtained within 30 min settling time. To enhance the treatment performances of Alg, WG was also evaluated as an alkali agent to further reduce the chemical oxygen demand (COD) and ammonia (NH 4 -N) in the wastewater. At equal doses of 3% of WG and Alg each, the combined treatment outcomes showed high turbidity and NH 4 -N removals of 83 and 89%, respectively, but the overall COD removal was at best 25%. The settling rate of treated sludge with combined Alg/WG was very rapid giving an SVI of 25.4 mL/g within only 5 min.