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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.)

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]