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Various treatment methods are widely used to reduce water pollution. Among these techniques, heterogeneous photocatalysis and non-thermal plasma technologies, notably dielectric barrier discharges, are currently the most suitable for water treatment. However, the use of each of these processes alone presents certain limitations. In this study, the brilliant blue (BB) photo-degradation was investigated via the dielectric barrier discharge (DBD) method. The impact of certain process factors, including the model pollutant's initial concentration (from 5 to 10 mg/L), the airflow rate (240 L/h) as well as the frequency (from 230 to 400 Hz), upon the DBD's performance in terms of bright blue decomposition and mineralisation was assessed. The latter reached 49.5% for 120 minutes, assuming optimised operating parameters (BB initial concentration of 10 mg/L, airflow rated at 240 L/h, 21 kV as an applied voltage at 400 Hz). It could be said that DBD processing has a high ecological potential for the aqueous degradation of BB. Scavenger analysis indicated that the radicals O2−°, HO2°, as well as °OH, represent the underlying oxygen reactive species in the process of brilliant blue decomposition. The study showed that both reactive nitrogen species and ROS contribute to the process of BB removal. For approximating real-life requirements, DBD tests were performed in both tap and synthetic water matrices. The degradation and mineralisation of BBs were significantly inhibited in tap water (% Degradation = 71.3, % Mineralisation = 31.6) and synthetic water (% Degradation = 65.41, % Mineralisation = 12), compared to BB degradation and mineralisation in ultrapure water (% Degradation ≥ 98, % Mineralisation = 49.5), after 120 min of irradiation. This proved that inorganic and organic molecules in tap and synthetic water reduce BB degradation efficiency. Thus, our pollutant was treated by the combination plasma-photocatalysis system using cellulose paper-supported titanium dioxide as a photocatalyst, which showed a significant improvement in BB decomposition efficiency versus considering either separate process. [ABSTRACT FROM AUTHOR]

The green synthesis of silver nanoparticles (AgNPs) using plant extracts is an eco-friendly method with potential for biomedical and environmental applications. This study aims to synthesize silver nanoparticles (SO-AgNPs) using Salvia officinalis L. extract and evaluate their antioxidant and antibacterial properties, positioning them as candidates for applications in sustainable biomedicine and wastewater treatment. S. officinalis L. extract was used to synthesize AgNPs under optimized conditions, with a 10% extract/AgNO₃ ratio and a reaction time of 180 min. The SO-AgNPs were characterized using ATR-FTIR, XRD, SEM, DLS, and Zeta potential analysis. The antioxidant activity of the extract and SO-AgNPs was evaluated using ABTS+• and DPPH• radical scavenging assays. Antibacterial activity was tested against 11 bacterial strains and bacteria isolated from industrial effluent, with minimal inhibitory concentrations (MIC) determined for both the extract and SO-AgNPs. The SO-AgNPs demonstrated potent antioxidant activity, with IC₅₀ values of 0.233 mg/mL and 0.305 mg/mL in the ABTS+• assay, and 0.173 mg/mL and 0.185 mg/mL in the DPPH• assay for the extract and SO-AgNPs, respectively. Antibacterial testing showed MIC values of 0.25 mg/mL for SO-AgNPs and between 3.12 and 6.25 mg/mL for S. officinalis L. extract against E. coli, P. aeruginosa, A. baumannii, MRSA, B. cereus, and S. epidermidis. For bacteria isolated from industrial effluent, the MIC values were 0.125 mg/mL for SO-AgNPs and 0.5 mg/mL for the extract. This study highlights the dual antioxidant and antibacterial capabilities of S. officinalis L. extract and SO-AgNPs, demonstrating their potential for use in both biomedical and environmental applications, including wastewater treatment. [ABSTRACT FROM AUTHOR]

In this research, the optimization of the electrochemical advanced oxidation treatment for the degradation of Clopidogrel was investigated. This study examined the influence of various experimental parameters including applied current, initial Clopidogrel concentration, and ferrous ion concentration by the use of the Doehlert design within a response surface methodology framework. The improved grey wolf optimizer was applied in order to define the optimum operating conditions. The monitoring of clopidogrel concentration during treatment revealed that complete disappearance of clopidogrel was achieved under an initial clopidogrel concentration of 0.02 mM, current intensity of 0.55 A, Fe2+concentration of 0.7 mM, and a reaction time of 20 min in a solution containing 50 mM Na2SO4 at pH 3. A quadratic polynomial model was developed, and its statistical significance was confirmed through the analysis of variance, demonstrating a high level of confidence in the model (R2 = 0.98 and p-value < 0.05). Furthermore, following electrolysis treatment for 480 min, the synthetic clopidogrel solutions underwent mineralization, achieving a 70.4% removal rate of total organic carbon. Subsequently, the applicability of the optimized process was tested on real pharmaceutical wastewater, and mineralization was investigated under the identified optimal conditions, resulting in a total organic carbon removal rate of 87% after 480 min of electrolysis time. The energy consumption for this system was calculated to be 1.4 kWh·kg−1 of the total organic carbon removed. These findings underscore the effectiveness and potential applicability of the electrochemical advanced oxidation for industrial wastewater treatment. [ABSTRACT FROM AUTHOR]

Wastewater effluent from the pharmaceutical, cosmetic, and chemical industries often contains pharmaceutical contaminants, making the reuse of wastewater a controversial practice. Physical and chemical methods have been unsuccessful in removing these pollutants on a large scale. Microalgal technology has been introduced as a promising tool to tackle this issue. This study evaluated the performance of Trichormus variabilis microalgae in removing three contaminants, namely ranitidine, tramadol, and gabapentin. Three concentrations of each compound were introduced into the microalgal culture medium. The effect of these pharmaceutical concentrations on growth, biomass production, photosynthetic pigments, and protein and lipid content was evaluated and compared with control cultures over 14 days. It was found that T. variabilis was able to remove 61–100% of these drugs. Moreover, the addition of 250 mg L–1 of ranitidine to the algae culture medium led to a 33.4% reduction in biomass growth. Adding 20 mg L–1 of tramadol and 200 mg L–1 of gabapentin caused 30% and 19.2% biomass reductions, respectively. The presence of 100 mg L–1 of gabapentin led to a 38% and up to 14% increase in chlorophyll and carotenoid content in comparison with the control, while the presence of the other drugs reduced the content of chlorophyll and carotenoid. On the other hand, the protein content increased by 254% in the culture media compared to the control media in the presence of 50 mg L–1 ranitidine. Regarding lipid concentration, 20 mg L–1 of tramadol had the most important effect by doubling the lipid content in T. variabilis in comparison with the control. In conclusion, these drugs could be removed to a significant extent by T. variabilis, which is promising for larger scale applications. [ABSTRACT FROM AUTHOR]

This innovative article provides a detailed description of the successful biosynthesis of zinc nanoparticles (ZnO-NPs) using an aqueous extract of Algerian Date Syrup, also known as molasses. A meticulous process was carried out to determine the optimal calcination temperature for ZnO-NPs, a crucial step in the preparation of these nanoparticles. The study was further extended by creating ZnO/rGOx nanocomposites through a hydrothermal method, varying the concentrations of reduced graphene oxide (rGO) at 5%, 10%, and 15%. The characteristics of the nanocomposites were thoroughly explored, encompassing chemical, optical, and morphological aspects, using sophisticated analysis techniques such as scanning electron microscopy (SEM), UV-visible diffuse reflectance spectroscopy (UV DRS), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). These analyses provided an in-depth understanding of the structure and properties of the nanocomposites. The centerpiece of this study is the evaluation of the photocatalytic degradation capacity of ZnO-NPs and ZnO/rGOx nanocomposites. These materials have demonstrated their ability to act as cost-effective and environmentally friendly photocatalysts for wastewater treatment. Experiments on methylene blue degradation under UV irradiation were conducted, yielding impressive results: a degradation efficiency of 86.6% was achieved in 140 min using 1 g/L of ZnO-NPs, and this rate reached 100% with the ZnO/rGO catalyst in the same time frame, highlighting its superiority as a photocatalyst. Furthermore, this study examined the variables affecting the photocatalysis experiment, including the solution's pH and the amount of catalyst. The results revealed that the ZnO/rGO photocatalyst reached its optimal efficiency under neutral pH conditions and at a concentration of 1 g/L, providing crucial information for practical use of these materials. This enriched article highlights the promising potential of ZnO-NPs and ZnO/rGOx nanocomposites as efficient photocatalysts for methylene blue degradation, paving the way for significant environmental applications in wastewater treatment. [ABSTRACT FROM AUTHOR]

Dyes are responsible for major environmental issues globally due to their toxicity, large-scale production, and extensive use in various industrial sectors. Pollution caused by hazardous dyes is mainly due to textile waste, which is constantly discharged into the aquatic system, often causing harm to humans and affecting water quality. In recent years, the removal of dyes from industrial textile wastewater has been a major challenge. Numerous technologies and methods have been developed to remove dyes from wastewater and meet clean water requirements. In this study, the effectiveness of activated carbon prepared by chemical activation of jujube stones for textile wastewater treatment was investigated. The effects of the concentration of H3PO4 and the carbonization temperature on the activated carbon's properties were studied. Several physicochemical methods, including Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction, methylene blue index, Boehm titration, iodine index and pH point of zero charge, were considered to characterize the produced adsorbents. To assess the quality of the two studied textile effluents (Mustard and Violet), the following parameters were used: biological oxygen demand (BOD), chemical oxygen demand (COD), turbidity, suspended particles and dissolved solids, before and after treatment with the produced activated carbon. Untreated wastewater analysis revealed high values for almost all parameters: pH > 9, COD of 302.72 mg/L and 230.68 mg/L for Mustard and Violet effluent, respectively. Both effluents from an industrial textile factory exhibited a COD/BOD ratio higher than three, which restricts their biodegradability. Examination of the effect of contact time and activated carbon dosage on the treatment of the two effluents showed that 4 g/L of activated carbon and 60 min of contact time were sufficient for optimal treatment, resulting in pollutant removal rates of 81.03 and 84.65% for the Violet and Mustard effluents, respectively. The results of this research highlight the efficiency of activated carbon derived from jujube stones as a cost-effective adsorbent for the treatment of real textile wastewater. [ABSTRACT FROM AUTHOR]

The "excess salt replication process" is a new simple method of fabrication of open-cell metal foam based on the commonly known salt replication method. Porous materials with porosity between 46% and 66% result when the employed alloy is 25% antimonial lead alloy and when it is 58% to 65% zamak 5. These foams are proposed as structured catalysts instead of packed beds in the treatment of wastewater. The local regimes influencing macroscopic air flow behaviour through these foams are delimited and boundaries are analysed in terms of sample length. Most of the experimental tests in this work exhibited a general trend of air flow in ESR foams dominated by the "strong inertia regime". It was established that the law governing the unidirectional air flow through these foams was the full cubic law. The permeability and inertia coefficient of five samples with a cell diameter between 2.5 and 4.5 mm were calculated, and an empirical correlation was fitted. The irregular cuboid shape of salt grains used in the ESR foam was the origin of the special cell form of ESR foams leading to an anisotropic ordered porous media. This can explain the macroscopic turbulence of air flow because there were many dead zones present in the corner of each cubic cell, thus causing kinetic energy loss starting at earlier regimes. [ABSTRACT FROM AUTHOR]

Domestic, agricultural and industrial water activities lead to organic and inorganic pollution of the environment. Biotreatment of municipal wastewater with the potential production of biomass is a valuable feature of microalgae. In this study we evaluated the effects of wavelength and light intensity on phosphate and ammonium removal on the one hand, and biomass and protein production on the other hand by Spirulina platensis in municipal wastewater treatment under semi batch cultivation. S. platensis was inoculated at 40% in artificial wastewater open pond system. Red, blue and purple light with 3800, 4800 and 5800 lux light intensity under 12 h light and 12 h darkness were investigated. Cultivation was conducted in semi-batch conditions; after four days cultivation, one third of the culture was replaced with fresh medium. The highest biomass and protein concentrations were observed under blue light at 5800 lux light intensity, 5.45 and 3 g/l respectively cumulatively; while the highest amount of phosphate and ammonium removal were about 145 and 218 mg/l under purple light at 5800 lux intensity, respectively. The amounts of biomass and protein produced, as well as phosphate and ammonium removed, are therefore impacted by wavelength, light intensity, results show that light intensity and wavelength can be customized to reach on the one hand the highest biomass and protein production, and on the other hand to maximize the removal of phosphorous and ammonium. [ABSTRACT FROM AUTHOR]

Some studies asserted that some aquatic plants can remove organic pollutants by degrading them into their biomass. In this work, it was aimed to examine the ability of L. gibba L. to remove two dyes, DR-89 and VB-20 and then to elucidate the mechanism of removal. For this purpose, experiments were conducted at 21±1 °C, 12h photoperiod and pH of 6.1± 0.01. For the maximal dye concentration tolerated by the plants (50 mg L-1), the results demonstrated that maximum dye abatement was determined to be about 53% (VB-20) and 23% (DR-89). In order to identify the mechanism of dye absorption, FT-IR, UV-vis and SEM analyses were conducted on the biomass and liquid phases. The results indicated that alcohol, alkene, phenol, and amine functions are involved in dye binding to the biomass surface without demonstrating any phytodegradation phenomenon. Additionally, the SEM analysis confirmed this result showing that the ventral lobe and the thin root of each frond (unlike the dorsal lobe) are colored via a direct interaction with the dye molecules allowing their absorption from the surrounding water. Thus, the invasive plant, L. gibba L. could remove organic dyes from contaminated mediums by accumulating them in the biomass without degrading them. [ABSTRACT FROM AUTHOR]

Fenton-like processes have been widely studied in recent years and are considered promising for organic wastewater treatment. Enhancement of wastewater treatment performance involves the development of economical and environmental aspects of the process. The present work aims to investigate the degradation and mineralization of an organic model compound, namely patent blue V (PBV) in aqueous solution. The process adopted uses the Fenton-like mode enhanced by UV light, using a low amount of reagent at natural pH, which was close to neutral. Some key parameters including UV light, H2O2 dosage, catalyst amount and initial dye concentration in the homogeneous Fenton-like processes were discussed. The complete degradation of 10 mg/L of PBV was obtained in 1 h with low reagent concentrations (0.98 mg/L and 39.1 mg/L of Fe3+ and H2O2, respectively) at natural pH (6.4). The mineralization was justified through the determination of sulfates, nitrates and calcium formed during oxidation. The reaction obeys the pseudo-first-order and kinetic constants, namely the apparent rate constant, the half-life time and the catalytic efficiency, strongly depend on the catalyst concentration. The reutilization of the generated sludge in the photo-Fenton-like process was discussed. However, in spite of the decrease in the degradation efficiency, the possibility of recycling the catalyst Fe3+ as sludge Fe(OH)3 makes the process photo-Fenton-like, cheaper and environment friendly. [ABSTRACT FROM AUTHOR]

Wastewater flow through a sand filter causes variations in the physical and chemical properties of the filter media. The objective of this study was to investigate and characterize the physical and chemical properties of dune sand filters after a certain period of operation. Lab-scale studies were performed using four dune sand filter columns for treating wastewater. The column was split into ten layers; each of which was through physical and chemical analyses after a certain operational period. It was observed that 34%–51% of the organic matter in the column was found in the top layer. The flow of wastewater caused a deposition of limestone and fine particles onto the filter. There was a noticeably low pH in the upper layers of the columns due to the high amounts of organic matter. Lastly, the virgin sands were more saturated in salts than the used sand after operation. [ABSTRACT FROM AUTHOR]

The aim of this study is the simultaneous biosorption of Cd+2 and Ni+2 on a dead biomass, Streptomyces rimosus pretreated with NaOH (0,1 M). Kinetic tests were carried out for the binary mixture (cadmium-nickel) during 6 hours contact time to ensure that balance was reached. The amounts adsorbed at equilibrium were 22.8 mg Ni2+/g and 9.86 mg Cd2+/g biomass, respectively. The biosorption depends mainly by some parameters, such as the pH, the initial concentration of metal and the initial concentration of biomass. The isotherm of adsorption according to two models, Langmuir and Freundlich, was carried out in our study. The results of the kinetics of adsorption show that the experimental values are well represented by the kinetic model of pseudo-second order. This enables us to determine the behavior of these adsorbents with respect to a real industrial effluent. [ABSTRACT FROM AUTHOR]

Cone biomass ofPinus brutia, a novel low-cost adsorbent prepared from forest waste has been utilized as an adsorbent for the removal of Congo red (CR) dye from an aqueous solution. The adsorbate concentration, pH, time, and temperature were examined in batch tests. Maximum biosorption capacity was 102.8?mg/g, showing that cone biomass ofP. brutiawas more efficient than most of the other adsorbents. Experimental data were analyzed by Langmuir, Freundlich, and Sips adsorption isotherms models and showed that the adsorption process followed a Sips model. Pseudo-first-order, pseudo-second-order, and intraparticle diffusion models were used to fit experimental data, showing that the adsorption of CR could be described by a pseudo-second-order equation and that intraparticle diffusion was not the only rate-limiting mechanism for the biosorption of CR. Thermodynamic parameters such as ?Go, ?Ho, and ?Sowere also evaluated and it was found that the sorption process was feasible, spontaneous, and endothermic in nature. These results indicated that cone biomass ofP. brutiais promising as a low-cost alternative compared to other commercial adsorbents for the removal of dyes from wastewater. [ABSTRACT FROM PUBLISHER]

The use of sand of dunes as a filtration support for domestic wastewater treatment demonstrated its efficiency at pilot scale. However, the filter receives non negligible amounts of suspended matter, leading to biological clogging owing to the colonization of the pores of the filtration media by biomass and related by-products. Fouling time-course was examined in this work. Measurements carried out at various column heights showed that the difference of porosity between the first and last layers can reach 2%, while the decrease between the initial and the final state was above 7% for all layers. Organic matter accumulation followed similar history than fouling, showing its involvement in the process and its preponderance in the fouling mechanism if compared to mechanical fouling. The amount of organic matter was mainly apparent in the two upper layers of sand and exceeded 2% in the first sand layer after 7 days. [ABSTRACT FROM AUTHOR]

The aim of this article was to examine the feasibility of combining an electrochemical degradation of wastewater containing Basic Yellow 28 (BY28) dye on Pb/PbO2 electrode and a biological treatment. A central composite design (CCD) was used for the screening of the significant operating parameters and the identification of the most relevant interactions. The model equation obtained led to a classification of these parameters based on their level of significance, namely temperature followed by the initial concentration of BY28, the current density and the agitation speed. A significant interaction occurred between the temperature and the initial dye concentration. The second-order model obtained by CCD led to the following optimal conditions for dye degradation: 50 ≤ T ≤ 60°C, 8.125 ≤ i ≤ 25 mA cm−2, [BY28]0 = 134 mg L−1, and ω = 720 rpm. Under these conditions, the obtained BY28 dye degradation yield was 96%. The (BOD5/COD) ratio increased from 0.076 initially to 0.30 after pretreatment, showing that the electrochemical pretreatment of BY28 dye generate intermediate products, which are at least partially biodegradable. Microbial degradation was therefore performed for the pretreated solution in an aerobic batch reactor for 30 days using an activated sludge culture. A decrease of the residual amount of intermediate products contained in the electrolyzed solutions was observed which can be related to a biological oxidation, leading to 93% removal of the dissolved organic carbon by the combined process. © 2013 American Institute of Chemical Engineers Environ Prog, 33: 160-169, 2014 [ABSTRACT FROM AUTHOR]

A fungal consortium including Aspergillus niger, Mucor hiemalis and Galactomyces geotrichum was tested for the treatment of dairy wastewater. The bio-augmentation method was tested at lab-scale (4 L), at pilot scale (110 L) and at an industrial scale in Wastewater Treatment Plants (WWTP). The positive impact of fungal addition was confirmed when fungi was beforehand accelerated by pre-culture on whey (5 g/L lactose) or on the dairy effluent. Indeed, chemical oxygen demand (COD) removal yields increased from 55% to 75% for model medium, diluted milk. While after inoculation of an industrial biological tank from a dairy factory with the fungal consortium accelerated by pre-cultivation in a 1000 L pilot plant, the outlet COD values decreased from values above the standard one (100 mg/L) to values in the range of 50–70 mg/L. In addition, there was a clear impact of fungal addition on the ‘hard’ or non-biodegradable COD owing to the significant reduction of the increase of the COD on BOD 5 ratio between the inlet and the outlet of the biological tank of WWTP. It was in the range of 451%–1111% before adding fungal consortium, and in the range of 257%–153% after bio-augmentation with fungi. An inoculated bioreactor with fungal consortium was developed at lab-scale and demonstrated successfully at pilot scale in WWTP. [ABSTRACT FROM AUTHOR]

The textile industry induces one of the main environmental pollution, mainly due to the dyes containing in its effluents. There is therefore a need for their treatment prior to discharge to the environment. The removal efficiency of Acid Red 18 and Acid Red 14 dyes by zero-valent iron were investigated in this study. The effect of some parameters such as pH (3-11), contact time (15-120 min), initial dye concentration (25-100 mg l-1) and initial concentration of iron powder (0.5-2 g l-1) were examined. The results showed that dye removal efficiency increased with increasing contact time and initial concentration of iron powder on the one hand, and decreased for increasing pH and initial dye concentration on the other hand. Experimental data were rather accurately fitted onto both first-order and second-order kinetic models, even if the first-order kinetic model led to higher correlation coefficients. Comparison of the kinetic rate constants showed a low impact of the initial dye concentration and that an acidic pH of 3 was optimal for the removal of Acid Red 14 and Acid Red 18. [ABSTRACT FROM AUTHOR]

A pilot plant involving a septic pit followed by sand filtration was used to treat urban wastewater in the south of Algeria. Experiments carried out in triplicates simultaneously in three identical pilot plants showed the feasibility of the process, since BOD5, COD and SS removals remained above 70% over 2.5 months of the experiment. The permeability of Sahara sand of dune allows therefore its use for water biofiltration; however an additional drainage should be considered to avoid salt problems. The next objective is the process validation on an industrial scale. [ABSTRACT FROM AUTHOR]

The aim of this study was to develop and validate a rapid analytical method for tetracycline (TC) determination in activated sludge. The analytical method developed is applicable on activated sludge containing a volatile suspended solid concentration below 10 g l-1, which nearly includes all wastewater treatment plants and the major proportion of membrane bioreactors. The analytical method included two steps: sample clean-up followed by high-performance liquid chromatography (HPLC) with ultraviolet (UV) detection analysis. Prior to the analysis, TC was extracted from the matrix by a mixture of EDTA and McIlvaine buffer. Sample clean-up was carried out by solid phase extraction (SPE) with strong anion exchange (SAX) cartridges. SAX cartridges retained organic matters interfering with TC. Analysis was performed by HPLC-UV with a gradient elution. The method was validated as the R2 value was 0.9991 for the calibration curve. Recoveries were between 92% (± 6%) and 103% (± 9%). The limit of detection (LOD) and the limit of quantification (LOQ) were 0.1 mg l-1 and 0.5 mg l-1, respectively. Accuracy was not entirely satisfactory, but should be related to the complexity of the matrix, which is a hindrance to the precision of the method. The method was also validated on industrial samples. [ABSTRACT FROM AUTHOR]

In the present study, methylene blue (MB) removal from aqueous solutions via the photocatalytic process using TiO2 as a catalyst in the presence of external ultra-violet light (UV) was investigated. The results of adsorption in the absence of UV radiation showed that adsorption reached an equilibrium state at 60 min. The experimental kinetic data were found to be well fitted by the pseudo-second-order model. Furthermore, the isotherm study suggested that dye uptake by TiO2 is a chemisorption process with a maximum retention capacity of 34.0 mg/g. The photodegradation of MB was then assessed under various experimental conditions. The related data showed that dye mineralization decreased when dye concentrations were increased and was favored at high pH values and low salt concentrations. The simultaneous presence of organic and inorganic pollution (Zinc) was also evaluated. The effect of the molar ratio Zn2+/MB+ in the solution at different pH values and NaCl concentrations was also monitored. The corresponding experimental results showed that at low values of Zn2+ in the solution (30 mg/L), the kinetic of the MB removal became faster until reaching an optimum at Zn2+/MB+ concentrations of 60/60 mg/L; it then slowed down for higher concentrations. The solutions' carbon contents were measured during the degradation process and showed total mineralization after about 5 h for the optimal Zn2+/MB+ condition. [ABSTRACT FROM AUTHOR]

This study provides an alternative solution for the bioremediation of a recalcitrant pharmaceutical micropollutant. Clofibric acid (CLA) was chosen as target molecule, because of its environmental persistence and resistance to wastewater treatment technologies. The aim of this study was to investigate the potential of a phenol-resistant Pseudomonas aeruginosa strain isolated from the activated sludge to degrade CLA. In order to evaluate the effect of acclimation process with glucose as carbon co-substrate, two protocols were performed, in which the transfer of the inoculum is carried out either in the exponential growth phase or in the decline phase. The results showed a removal efficiency of CLA of 35% when cells in the decline phase were used for inoculation. In contrast, a very low removal yield (10%) was achieved when cells harvested in the exponential phase were used as inoculum. This work is the first one reporting on the capability of this bacterium to remove this drug. The obtained data showed that the isolated strain is able to degrade target molecule and might be a promising agent for the elimination of this refractory compound. [ABSTRACT FROM AUTHOR]

Environmental pollution, particularly from industrial dyes and chemicals, poses a significant threat to ecosystems and human health. Traditional pollution mitigation methods are often inefficient and costly. Photocatalysis has emerged as a promising solution for degrading pollutants using light energy. Titanium dioxide (TiO 2) is a widely studied photocatalyst due to its stability, non-toxicity, and strong oxidative power. However, its efficiency is limited by a wide bandgap, restricting absorption to the UV region, and rapid electron-hole recombination. To address these limitations, doping TiO 2 with materials (La 2 O 3 and CuO) can enhance its photocatalytic activity under visible light. This study investigates the enhancement of TiO 2 nanocomposites by incorporating La 2 O 3 and CuO. X-ray diffraction (XRD) revealed that the nanocomposites retained the TiO 2 anatase and rutile phases with their improved crystallinity. Scanning electron microscopy (SEM) displayed spherical nanoparticles forming agglomerates, typically due to high surface energy. Energy-dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS) confirmed the presence of La and Cu in the TiO 2 matrix. Fourier-transform infrared (FTIR) spectroscopy identified characteristic vibrational modes of Ti–O, La–O, and Cu–O bonds, suggesting strong interactions between dopants and TiO 2 lattice. Ultraviolet–visible (UV–vis) spectroscopy showed a red shift in absorption spectra with La 2 O 3 and CuO addition, reducing the bandgap energy from 3.23 eV (pure TiO 2) to 2.27 eV for the TiO 2 –0.1La 2 O 3 –0.2CuO composite. Photoluminescence (PL) spectroscopy indicated improved charge separation and reduced electron-hole recombination rates in the synthesized nanocomposites. Photocatalytic performance was evaluated by degrading brilliant green (BG) dye under visible light. The TiO 2 –0.1La 2 O 3 –0.2CuO (TLC 0.2) nanocomposite achieved the highest dye degradation of over 95% after 204 min under optimal conditions (C o = 17 mg/L and 1 g/L). Adding the inorganic agent Na 2 SO 4 to this process significantly enhanced the photocatalytic activity, increasing degradation from 56% to 95% after 180 min of visible light irradiation. TLC 0.2 exhibited a high stability of dye degradation efficiency after six consecutive photocatalysis cycles. La 2 O 3 and CuO doping significantly enhance TiO 2 nanocomposites' crystalline structure, morphology, optical property, and photocatalytic efficiency. TLC 0.2 has a potential use for environmental remediation and solar energy conversion. [ABSTRACT FROM AUTHOR]

Effective aerobic/anoxic treatment of piggery manure wastewater was achieved in a real farm scale using a small piggery (72 pigs) with reuse of the treated water. The experimental procedure was followed for 9 months. Fresh manure (FM) is formed by daily flush on piggeries and biologically treated after centrifuge pre-treatment. For upgrade liquid/solid separation and pathogen retention in biological treatment, a membrane system was used with the aim of effluent reuse in flush. Despite an evolution of FM through time, centrifuge pre-treatment and bioreactor performances stayed at high level. An elimination of 86% of the suspended solids occurred through pre-treatment, and nitrogen and COD biological degradation remains at 90% all time long. Moreover, interestingly about half of the soluble part of phosphorus (20% of the global phosphorus content) was biologically removed via the recirculation between the anoxic and the aerobic tank which acted as an intermittent aerobic/anoxic sequence. A part of COD was proved not biodegradable and was accumulated via the reuse of the treated water for flushing purpose. This accumulation justifies washing of the biomass between two runs in purpose to enhance the treated water quality and also to meet the membrane tolerance. The membrane was proved reliable as far as the maintenance procedure was respected. Maintenance cleaning had to be operated as soon as the TransMembrane Pressure (TMP) achieved 50mbar and curative washing was necessary if the TMP increased over 90mbar or between 2 runs. The temperature was proved to influence both the bioactivity and the membrane fouling kinetic. Finally, it was demonstrated that the process was sustainable for long-term management of swine wastewater at semi-industrial scale. [Copyright &y& Elsevier]

[Display omitted] • Orange peel beads are synthesized for methylene blue (MB) adsorption. • H 3 PO 4 acid and encapsulation are used to improve the adsorption capacity. • MB adsorption mechanism and its thermodynamic behavior are investigated using MMTE model. • SVM model optimized by LFD is used for accurate prediction of MB adsorption. • A user-friendly application is developed for optimization and prediction of MB adsorption. This study investigates the use of orange peels as a precursor for synthesizing sodium alginate-encapsulated beads for methylene blue (MB) removal. The prepared beads (BOP1 and BOP2) underwent characterization through FTIR, XRF, SEM and TGA. Subsequently, the impacts of various factors, including temperature, the initial pH, initial concentration, salt and humic acid, are studied. The adsorption isotherms show high adsorbed quantities of 764.92 and 659.78 mg/g for BOP1 and BOP2 respectively, while the obtained data are best described by the monolayer with two energies (MMTE) model, which is then used to perform a thermodynamic study of the MB adsorption mechanism. Additionally, the adsorption kinetics data are modeled using three models, with the PFO model identified as the most appropriate. The regenerated beads demonstrate the ability to be reused up to 7 cycles, The effects of NaCl and humic acid on MB adsorption reveal that NaCl inhibits adsorption due to competition with Na+, while humic acid has no effect. Finally, a support vector machine (SVM) model optimized by the Levy Flight Distribution Optimization (LFD) algorithm is developed and found to be capable of accurately predicting the adsorption behavior of the prepared beads. This model is then used in optimizing the process conditions for maximal MB removal. Overall, this study demonstrates that the prepared beads could be potential low-cost and environmentally friendly adsorbents for wastewater treatment applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Successful synthesis of n–p heterojunction catalysts (TiO 2 –Bi 2 O 3 –CuO) using the ceramic method. • Optimal optical property achieved with TiO 2 –0.2Bi 2 O 3 –0.25CuO supported on natural zeolite under ultrasonic waves. • 94.1% removal efficiency for Safranin-O dye in distilled water and 80.23% in textile wastewater under sunlight. • UV–visible spectra showed improved performance with the addition of Bi 2 O 3 and CuO. • Effective results for the removal of Safranin-O dye with the adsorption-photocatalysis coupling. A series of n – p heterojunction catalysts (TiO 2 –Bi 2 O 3 –CuO) were synthesized by the ceramic method. X-ray diffraction, scanning electron microscopy coupled with energy dispersive X-ray, Fourier transform infrared spectroscopy (FTIR), UV–visible spectroscopy, and photoluminescence were used for the characterization of the synthesized materials. The optical optimization demonstrated that the solid solution TiO 2 –0.2Bi 2 O 3 –0.25CuO exhibited the best optical property. This catalyst supported on natural zeolite under ultrasonic waves improved notably the adsorption-photodegradation capacity of the resultant material. The impact of the n – p junction supported on zeolite on the photodegradation of a polluting solution showed excellent results for the degradation of cationic dye with removal efficiency reaching 94.1% and 80.23% under sunlight for Safranin-O dye in distilled water and in wastewater from a local textile dyeing plant. [ABSTRACT FROM AUTHOR]

A kaolin-based iron molybdate Fe 2 (MoO 4 ) 3 -kaolin-450 (FM-kaolin-450), was successfully prepared through wet chemical process and characterized by scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDXS), X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), Fourier transform infrared spectrometry (FT-IR) and X-ray photoelectron spectroscopy (XPS). Acting as particle electrodes, FM-kaolin-450 was applied in electrochemical degradation of methyl orange (MO) in aqueous solution. The effects of initial pH, particle electrodes dosage, initial MO concentration, and current density on chemical oxygen demand (COD) removal efficiency of MO were investigated. The results demonstrated that FM-kaolin-450 shows better catalytic properties and stability in MO electrocatalytic degradation. In order to further test its catalytic performance, some other dyes (Acid Orange II, Eeriochrome Blue Black R, and Methylene Blue) were also studied and the results showed that above 97% decoloration was observed for all tested dyes, indicating that FM-kaolin-450 could act as an efficient particle electrode in color removal in most dye wastewater. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this work was to examine biodegradability improvement of tetracycline-containing solutions after an electrochemical pre-treatment, since about 70% of the applied drugs are not metabolized and hence can be found in wastewaters. Cyclic voltammetry with a vitreous carbon electrode revealed a significant electrochemical activity of tetracycline. Electrochemical treatment was therefore performed in a home-made flow cell. The effect of some operating conditions, tetracycline concentration, flow rate and the applied potential was investigated. Optimal conditions led to more than 99% conversion yield of tetracycline in oxidation and reduction, using a neutral salt as supporting electrolyte. TOC analyses of the electrolyzed solution revealed that the level of mineralization remained low, underlying the interest of a combined electrochemical and biological treatment. The biodegradability, based on the BOD5 on COD ratio, increased with the oxidation potential from 0.13 to 0.39, namely a biodegradable solution, for 1.0 and 1.6V/SCE, respectively. None of the electrolyzed solutions in reduction was biodegradable even if it was not toxic for the activated sludge. If the reduction is combined with a subsequent oxidation, BOD5/COD ratio reached a value of 0.39 when the oxidation at 1.0V/SCE was preceded by a reduction at −1.3V/SCE. [Copyright &y& Elsevier]

This work aimed at presenting a green method using a new source of peroxidase isolated from Raphanus sativus var. niger (RSVNP) in immobilized form, for the treatment of wastewater. To ensure stability and enzymatic activity in the biodegradation process, RSVNP was immobilized as a cross-linked enzyme aggregate (CLEAs). With more than 29% of recovered activity and 85% aggregation yield, acetone was selected as the best precipitating agent. The formed protein aggregates required 2% (v/v) of glutaraldehyde (GA) concentration and a ratio of 9:1 (v/v) enzyme (E) amount to cross-linker (E/GA). Compared to the free enzyme, RSVNP-CLEAs were found more chemically and thermally stable and exhibited good storage stability for more than 8 weeks. In addition, RSVNP-CLEAs were evaluated for their ability to remove phenol and p-cresol from aqueous solution by varying several operating conditions. A maximal yield (98%) of p-cresol conversion was recorded after 40 min; while 92% of phenol was degraded after 1 h duration time. The reusability of RSVNP-CLEAs was tested, displaying 71% degradation of phenol in the third batch carried out and more than 54% was achieved for p-cresol after four successive reuses in the presence of hydrogen peroxide at 2 mM concentration. ga1 • A new source of peroxidase was immobilized for phenolic compounds treatments. • Crosslinked peroxidase showed better physical and thermal stability compared to the free enzyme. • Immobilized peroxidase retained 100% activity after storage at 4 °C for 8 weeks. • RSVNP-CLEAs were able to remove 92% of phenol and 98% of p-cresol. • More than 71% degradation of phenols was achieved after 3 successive reuses. [ABSTRACT FROM AUTHOR]