Efficient removal of oxytetracycline antibiotic from aqueous media using UV/g-C3N4/Fe3O4 photocatalytic process.

Residual pharmaceuticals in the environment are a class of emerging pollutants that endanger human health. Tetracycline's family, including oxytetracycline (OTC), are known as one of the most produced and consumed antibiotics worldwide. The g-C3N4/Fe3O4 nanocomposite with high level of catalytic efficiency features suitable performance in water/wastewater treatment. Therefore, in the present study, this nanocomposite was applied to remove the oxytetracycline from the aqueous environment. In this research study, g-C3N4/Fe3O4 nanocomposite (serving as catalyst) was initially synthesized by a simple hydrothermal method. The effect of key operating parameters such as initial solution pH, dose of catalyst, contact time and initial concentration of OTC in aqueous solutions was investigated under UV irradiation. In addition, COD and TOC tests, the kinetics and the effect of radical scavengers on the applied photocatalytic process were all evaluated. The maximum removal efficiency of OTC (99.8 %) was achieved under the following conditions: neutral solution pH 7; catalyst dose, 0.7 g/L; and an initial OTC concentration of 5 mg/L. The data showed that the kinetics of the reaction followed the first-order model with R2 of 0.9755. The respective COD and TOC efficiency values for the applied photocatalytic process were determined to be 87 and 59 %, respectively. In addition, the lowest removal efficiency of OTC was observed in the presence of tert-butanol radical scavengers, and OH radicals played a main role. The UV/g-C3N4/Fe3O4 photocatalytic process proved to be highly efficient for the removal of OTC antibiotic and could be potentially applied for the removal of other pollutants from aqueous solutions.

Novel nanostructure approach for antibiotic decomposition in a spinning disc photocatalytic reactor.

Conventional wastewater treatment processes are often unable to remove antibiotics with resistant compounds and low biological degradation. The need for advanced and sustainable technologies to remove antibiotics from water sources seems essential. In this regard, the effectiveness of a spinning disc photocatalytic reactor (SDPR) equipped with a visible light-activated Fe3O4@SiO2-NH2@CuO/ZnO core-shell (FSNCZ CS) thin film photocatalyst was investigated for the decomposition of amoxicillin (AMX), a representative antibiotic. Various characterization techniques, such as TEM, FESEM, EDX, AFM, XRD, and UV-Vis-DRS, were employed to study the surface morphology, optoelectronic properties, and nanostructure of the FSNCZ CS. Key operating parameters such as irradiation time, pH, initial AMX concentration, rotational speed, and solution flow rate were fine-tuned for optimization. The results indicated that the highest AMX decomposition (98.7%) was attained under optimal conditions of 60 min of irradiation time, a rotational speed of 350 rpm, a solution flow rate of 0.9 L/min, pH of 5, and an initial AMX concentration of 20 mg/L. Moreover, during the 60 min irradiation time, more than 69.95% of chemical oxygen demand and 61.2% of total organic carbon were removed. After the photocatalytic decomposition of AMX, there is a substantial increase in the average oxidation state and carbon oxidation state in SDPR from 1.33 to 1.94 and 3.2, respectively. Active species tests confirmed that ·OH and ·O2- played a dominant role in AMX decomposition. The developed SDPR, which incorporates a reusable and robust FSNCZ CS photocatalyst, demonstrates promising potential for the decomposition of organic compounds.

Sono-assisted photocatalytic degradation of ciprofloxacin in aquatic media using g-C3N4/MOF-based nanocomposite under visible light irradiation.

This research study is centered on the sono-assisted photocatalytic degradation of a well-known antibiotic (ciprofloxacin; CIP) in aquatic media using a g-C3N4/NH2-UiO-66 (Zr) catalyst under visible light irradiation. Initially, the catalyst was prepared by a simple method, and its physiochemical features were thoroughly analyzed by XRD, FT-IR, FE-SEM, EDX, EDS-Dot-Mapping, and UV-Vis analytical techniques. After that, the impact of several influential factors affecting the performance of the applied sono-assisted photocatalytic process such as the initial concentration of CIP, solution pH, catalyst dosage, light intensity, and ultrasound power was fully assessed, and the optimal conditions were established. After 75 min of the sono-assisted photocatalytic treatment, the complete degradation of CIP (10 mg/L) was accomplished under the condition as follows: g-C3N4/NH2-UiO-66 (Zr), 0.6 g/L; pH, 5.0, and ultrasound power, light intensity 75 mw/cm2, 200 W/m2. Meanwhile, the photocatalytic degradation of CIP followed the pseudo-first-order kinetic model. In addition, the scavenger experiments demonstrated that OH˚ and O2°- radicals played a key role in the sono-assisted photocatalytic degradation process. It is also acknowledged that the applied catalyst was reused for five consecutive runs with a minor loss observed in its degradation efficiency. In a further experiment, a significant synergistic effect with regard to the degradation of CIP was observed once all three major parameters (visible light, ultrasound waves, and catalyst) were used in combination compared to each used alone. To sum up, it is thought that the integration of g-C3N4/MOF-based catalyst, ultrasound waves, and visible light irradiation could be potentially applied as a promising strategy for the degradation of various pharmaceuticals on account of high degradation performance, simple operation, excellent reusability, and eco-friendly approach.

A new MOF-based modified adsorbent for the efficient removal of Hg(ii) ions from aqueous media: isotherms and kinetics.

Herein, a new MOF-based modified adsorbent for the efficient removal of Hg(ii) ions from water media was successfully prepared. Initially, a MOF nanocomposite was synthesized and applied as an efficient adsorbent for the removal of the target heavy metal ion. Following the synthesis, the MOF-based modified adsorbent was identified and characterized by SEM, XRD and FT-IR analytical instruments. The impact of several key variables such as pH of aqueous solution, adsorbent dosage, contact time, and initial concentration of the analyte of interest on the adsorption efficiency was also investigated in detail. Under the optimal conditions established (pH, 3; dose of adsorbent, 0.4 g L-1; contact time, 40 min and the analyte's concentration of 1 mg L-1) the removal efficiency of 96.3% for Hg(ii) was obtained. The results of the studies on the isotherm and kinetics of adsorption revealed that the adsorption process of Hg(ii) matched with the Langmuir isotherm (R2 > 0.990) and the pseudo 2nd-order kinetic models (R2 > 0.998). Additionally, reuse of the applied adsorbent for five consecutive tests exhibited a small percentage of drop (about 8%) in the removal efficiency of the target ion. Finally, the results indicated that the MOF-based modified compound could be potentially applied as a highly efficacious adsorbent for the discharge of Hg(ii) from aquatic media.

Enhancing oxygen reduction reaction performance through eco-friendly chitosan gel-assisted molten salt strategy: Small NiCo alloy nanoparticles decorated with high-loading single Fe-NX.

We developed an effective and eco-friendly strategy using chitosan gel-molten salt to achieve high loading (2.23 At. %) of single Fe-NX as assistive active sites. These sites were combined with small NiCo alloy NPs distributed on porous carbon aerogels to boost the ORR performance. The FeSAs-NiCo alloy@N-C sphere exhibits exceptional mass activity and specific activity of 3.705 A.mg-1 and 8.79 mA.cm-2(ECSA), respectively, at 0.85 V versus RHE. It has a superior onset potential of 1.08 V versus RHE, surpassing that of its nanoparticle Fe counterpart and NiCo alloy@N-C sphere. The significant improvement in ORR performance of the FeSAs-NiCo alloy@N-C sphere could be attributed to the positive effects of increased lattice strain due to the single atoms of Fe-NX hybridized with small NiCo alloy NPs. The chitosan gel-assisted molten salt strategy and assistive active sites of Fe-NX hybridized with NiCo alloy NPs regulate the electronic properties of the FeSAs-NiCo alloy@N-C sphere, both geometrically via lattice strain mismatch and electronically through shifting of the d-band center. This could influence the binding energies for oxygen and/or oxygen reduction intermediate adsorption/desorption. The additional improvement in the ORR performance of the FeSAs-NiCo alloy@N-C sphere also benefits from having a lower electrochemical activation energy.

Biosolids, an important route for transporting poly- and perfluoroalkyl substances from wastewater treatment plants into the environment: A systematic review.

The pervasive presence of poly- and perfluoroalkyl substances (PFAS) in diverse products has led to their introduction into wastewater systems, making wastewater treatment plants (WWTPs) significant PFAS contributors to the environment. Despite WWTPs' efforts to mitigate PFAS impact through physicochemical and biological means, concerns persist regarding PFAS retention in generated biosolids. While numerous review studies have explored the fate of these compounds within WWTPs, no study has critically reviewed their presence, transformation mechanisms, and partitioning within the sludge. Therefore, the current study has been specifically designed to investigate these aspects. Studies show variations in PFAS concentrations across WWTPs, highlighting the importance of aqueous-to-solid partitioning, with sludge from PFOS and PFOA-rich wastewater showing higher concentrations. Research suggests biological mechanisms such as cytochrome P450 monooxygenase, transamine metabolism, and beta-oxidation are involved in PFAS biotransformation, though the effects of precursor changes require further study. Carbon chain length significantly affects PFAS partitioning, with longer chains leading to greater adsorption in sludge. The wastewater's organic and inorganic content is crucial for PFAS adsorption; for instance, higher sludge protein content and divalent cations like calcium and magnesium promote adsorption, while monovalent cations like sodium impede it. In conclusion, these discoveries shed light on the complex interactions among factors affecting PFAS behavior in biosolids. They underscore the necessity for thorough considerations in managing PFAS presence and its impact on environmental systems.

Association between visceral adiposity and generalized anxiety disorder (GAD).

BACKGROUND AND OBJECTIVES: Due to an increased rate of inflammation in generalized anxiety disorder (GAD), insight into the mediating factors in the onset and recurrence of the inflammatory response can help to achieve novel treatments for alleviating the risk of GAD. In the current study, we aimed to evaluate the possible relationship between visceral adipose tissue (VAT) as an important intermediary in inflammation pathways and GAD in participants of the Employees' Health Cohort Study of Iran (EHCSIR). METHOD: We analyzed the data from 3889 included participants aged > 18 years in the EHCSIR study, which were collected from 2017 to 2020. Lifetime and 12-month GAD were assessed using the Composite International Diagnostic Interview (CIDI-2.1) questionnaire. The adjusted prevalence ratio was computed to evaluate the association between GAD and visceral adiposity index (VAI), GAD and visceral fat area (VFA), GAD and body mass index (BMI) and ultimately GAD and waist circumference (WC) in males and females using STATA software. RESULTS: Log-binomial analysis showed a higher prevalence ratio of 12-month GAD associated with VFA in women [PR: 1.42, CI: 1.07-1.87, P: 0.015]. The prevalence of lifetime GAD was higher in obese women (BM1 > 30) [PR: 2.35, CI: 1.07-5.13, P:0.03] than in women with normal BMI. Women with higher VAI were also significantly more likely to suffer lifetime GAD [PR: 1.25, CI: 1.05]. 1.48, P:0.01]. In males, the prevalence of lifetime diagnosed GAD per 1 standard deviation increase in VFA was 0.65 [CI: 0.46-0.91, P: 0.01]. CONCLUSION: Visceral adiposity as a positive agent was associated with GAD prevalence in women. The presence of GAD symptoms showed no relationship to VFA in men.

Photocatalytic degradation of ciprofloxacin using a novel carbohydrate-based nanocomposite from aqueous solutions.

Pharmaceutical substances in the ecosystem pose a notable hazard to human and aquatic organism well-being. The occurrence of ciprofloxacin (CIP) within water sources or the food chain can perturb plant biochemical processes and induce drug resistance in both humans and animals. Therefore, effective removal is imperative prior to environmental discharge. This study introduces a Novel Carbohydrate-Based Nanocomposite (Fe3O4/MOF/AmCs-Alg) as a proficient photocatalytic agent for degrading CIP in aqueous solutions. The fabricated nanocomposite underwent characterization using FTIR, XRD, FESEM, DRS, and VSM techniques. The analyses conducted verified the successful synthesis of the Fe3O4/MOF/AmCs-Alg nanocomposite. Utilizing the optimized parameters (pH = 5, nanocomposite dose = 0.4 g/L, CIP concentration = 10 mg/L, light intensity = 75 mW/cm2, and a duration of 45min), the Fe3O4/MOF/AmCs-Alg/Vis nanocomposite demonstrated an impressive CIP degradation efficiency of 95.85%. Under optimal experiment conditions, CIP removal efficiency in tap water and treated wastewater samples was 91.27% and 76.78%, respectively. Furthermore, the total organic carbon (TOC) analysis indicated a mineralization rate of 51.21% for CIP. Trapping studies demonstrated that the superoxide radical (O2°-) had a notable contribution to the breakdown of CIP. In summary, the Fe3O4/MOF/AmCs-Alg/Vis system offers numerous benefits, encompassing effective degradation capabilities, effortless catalyst retrieval, and remarkable nanocomposite reusability.

UiO66-NH2-TiO2/NiF photoanode for photocatalytic fuel cell by towards simultaneous treatment of antibiotic wastewater and electricity generation.

Environmental destruction, water crisis, and clean energy are among the very important challenges worldwide based on sustainable development goals. Photocatalytic fuel cell, a potential candidate for converting chemical energy into electrical energy through a pollution-free method, holds promise in addressing these challenges. In this regard, we investigated the response of a photoanode covered with UiO66-NH2-TiO2/NiF on a porous nickel foam as an attractive electrochemical response to remove antibiotics from aqueous solution and simultaneously produce electricity using a one-step hydrothermal synthesis. Nickel foam with its fine structure provides a suitable space for the interaction of light, catalyst, and efficient mass transfer of reactive molecules. It appears that it can be used as a competitive electrode in fuel cells. In order to investigate the properties of the photocatalyst, structural analyses including XRD, FESEM, FTIR, and UV-vis DRS were utilized. Additionally, polarization and electrochemical tests such as chronoamperometry and EIS were measured to further examine the electrochemical features of the PFC photoanode system. The obtained results under optimal conditions (SMZ concentration = 20 ppm, pH = 6, irradiation time = 120 min) were as follows: removal efficiency of 91.7%, Pmax = 16.98 µW/cm2, Jsc = 96.75 µA/cm2, Voc = 644 mV. The light-induced current flow in UiO66-NH2-TiO2/NiF exhibited prominent and reproducible photocurrent responses, indicating efficient and stable charge separation in TiO2/NiF composite materials, which is a promising strategy for pollutant removal and simultaneous electricity generation.

Enhanced photocatalytic degradation of amoxicillin using a spinning disc photocatalytic reactor (SDPR) with a novel Fe3O4@void@CuO/ZnO yolk-shell thin film nanostructure.

Antibiotics are resistant compounds with low biological degradation that generally cannot be removed by conventional wastewater treatment processes. The use of yolk-shell nanostructures in spinning disc photocatalytic reactor (SDPR) enhances the removal efficiency due to their high surface-to-volume ratio and increased interaction between catalyst particles and reactants. The purpose of this study is to investigate the SDPR equipped to Fe3O4@void@CuO/ZnO yolk-shell thin film nanostructure (FCZ YS) in the presence of visible light illumination in the photocatalytic degradation of amoxicillin (AMX) from aqueous solutions. Stober, co-precipitation, and self-transformation methods were used for the synthesis of FCZ YS thin film nanostructure and the physical and chemical characteristics of the catalyst were analyzed by XRD, VSM,, EDX, FESEM, TEM, AFM, BET, contact angle (CA), and DRS. Then, the effect of different parameters including pH (3-11), initial concentration of AMX (10-50 mg/L), flow rate (10-25 mL/s) and rotational speed (100-400 rpm) at different times in the photocatalytic degradation of AMX were studied. The obtained results indicated that the highest degradation efficiency of 97.6% and constant reaction rate of AMX were obtained under LED visible light illumination and optimal conditions of pH = 5, initial AMX concentration of 30 mg/L, solution flow rate of 15 mL/s, rotational speed of 300 rpm and illumination time of 80 min. The durability and reusability of the nanostructure were tested, that after 5 runs had a suitable degradation rate. Considering the appropriate efficiency of amoxicillin degradation by FCZ YS nanostructure, the use of Fe3O4@void@CuO/ZnO thin film in SDPR is suggested in water and wastewater treatment processes.

Utilization of the copper recovered from waste printed circuit boards as a metal precursor for the synthesis of TiO2/magnetic-MOF(Cu) nanocomposite: Application in photocatalytic degradation of pesticides in aquatic solutions.

In this study, a number of leaching solutions (H2SO4, CuSO4 and NaCl) and an electrochemical method were used together for the separation of Cu from waste printed circuit boards. Secondly, the magnetic-MOF(Cu) was synthesized using the Cu recovered from waste printed circuit boards. Thereafter, TiO2/mag-MOF(Cu) composite was prepared and its photocatalytic activity was assessed in the photo degradation of two prominent organophosphorus pesticides, namely malathion (MTN) and diazinon (DZN). The catalytic structure of the MOF-based composite was fully characterized by various analyses such as XRD, SEM, EDAX, FT-IR, VSM and UV-vis. The obtained analyses confirmed the successful synthesis of TiO2/mag-MOF(Cu) composite. The synthesized composite exhibited highly efficient in the degradation of both pollutants under the following conditions: pH 7, contaminant concentration 1 mg/L, the catalyst dosage of 0.4 g/L, visible light intensity 75 mW/cm2 and reaction time of 45 min. First order kinetic model was best suited with the experimental results (R2: 0.97-0.99 for different MTN and DZN concentrations). Trapping studies revealed that superoxide radicals (O2•-) played an important role during the degradation process. Furthermore, the catalyst demonstrated a superb recovery as well as high stability over five cyclic runs of reuse. In addition, the total organic carbon (TOC) analysis showed over 83% and 85% mineralization for MTN and DZN, respectively. The combined system of TiO2/mag-MOF(Cu)/Vis also exhibited a great level of efficiency and feasibility in the treatment of tap water and treated wastewater samples. It is concluded that TiO2/mag-MOF(Cu) could be used as an excellent catalyst for the photodegradation of MTN and DZN in aqueous solution.

A comparative study on polyaluminum chloride (PACl) and Moringa oleifera (MO) chemically enhanced primary treatment (CEPT) in enhanced biogas production: anaerobic digestion performance and the Gompertz model.

A comparative study was performed to estimate biogas production from sludge produced by organic and inorganic chemically enhanced primary treatments (CEPTs). To this end, the effects of two coagulants, polyaluminum chloride (PACl) and Moringa oleifera (MO), on CEPT and biogas production in anaerobic digestion were surveyed within an incubation period of 24 days. The optimal dosage and pH of PACl and MO were optimized in terms of sCOD, TSS and VS parameters in the CEPT process. Next, the digestion performance of anaerobic digestion reactors fed with sludge obtained from PACl and MO coagulants at a batch mesophilic reactor (37 ± 1 °C) was surveyed from the biogas production, volatile solid reduction (VSR) and Gompertz model. At the optimal conditions (pH = 7 and dosage = 5 mg L-1), the removal efficiency of COD, TSS and VS in CEPT assisted with PACL was 63, 81 and 56%, respectively. Moreover, CEPT assisted with MO led to the removal efficiency of COD, TSS and VS until 55, 68 and 25%, respectively. The highest methane yield (0.598 L gVS removed-1) was obtained in an anaerobic digestion reactor with sludge from the MO coagulant. The anaerobic digestion of CEPT sludge instead of primary sludge resulted in higher sCOD removal efficiency, and 43-50% of sCOD was observed compared with the removal of 32% for the primary sludge. Furthermore, the high coefficient of determination (R2) demonstrated the trustworthy predictive precision of the modified Gompertz model with actual data. The combination of CEPT and anaerobic digestion, especially using natural coagulants, provides a cost-effective and practical way to increase BMP from primary sludge.

Benzo (a) pyrene in infant foods: a systematic review, meta-analysis, and health risk assessment.

Exposure of infants to chemicals during their development will have major effects on their health. One of the major exposures of infants to chemicals is through their food. The main structure of infant food is milk, which is high in fat. There is a possibility of accumulation of environmental pollution, including benzo (a) pyrene (BaP). In this systematic review, the amount of BaP in infant milk was surveyed for this purpose. The chosen keywords were: benzo (a) pyrene, BaP, Infant formula, dried milk, powdered milk, and baby food. A total of 46 manuscripts were found in the scientific database. After initial screening and quality assessment, 12 articles were selected for extraction of data. By meta-analysis, the total estimate of BaP in baby food was calculated to be 0.078 ± 0.006 µg/kg. Estimation of daily intake (EDI) and Hazard Quotient (HQ) for noncarcinogenic risk and Margin of exposure (MOE) for carcinogenic risk were also calculated for three age groups 0-6 months, 6-12 months, and 1-3 years. HQ was lower than 1 and MOE was more than 10,000 for three age groups. Therefore, there is no potential carcinogenic and non-carcinogenic risk for infant health.

Association Between Non-alcoholic Fatty Liver Disease and Heavy Metal Exposure: a Systematic Review.

Non-alcoholic fatty liver disease (NAFLD) is a debilitating disease with adverse effects including cirrhosis and hepatocellular carcinoma. Heavy metals can cause severe dysfunction in different body organs including the liver. This review offers the study regarding the positive or negative association between heavy metals exposure and non-alcoholic fatty liver disease. The method used in this study is a systematic review based on searching in the PubMed, Scopus, and Science direct databases with the keywords of fatty liver, non-alcohol fatty liver, heavy metal, mercury, cadmium, arsenic, chromium, thallium, lead, iron, zinc, and nickel. There were 2200 articles searched in databases, and after assessment, 28 articles were selected. Positive association is established between arsenic, cadmium, iron, lead, mercury, and fatty liver disease. A negative relationship is found between zinc, copper, and progressive fatty liver disease. Furthermore, laboratory methods for NAFLD diagnosis were examined according to the obtained manuscripts. Among the different diagnostic methods, magnetic resonance imaging (MRI) is a sensitive method.

Investigation of photocatalytic-proxone process performance in the degradation of toluene and ethyl benzene from polluted air.

In this study, toluene and ethylbenzene were degraded in the photocatalytic-proxone process using BiOI@NH2-MIL125(Ti)/Zeolite nanocomposite. The simultaneous presence of ozone and hydrogen peroxide is known as the proxone process. Nanocomposite Synthesis was carried out using the solvothermal method. Inlet airflow, ozone concentrations, H2O2 concentrations, relative humidity, and initial pollutants concentrations were studied. The nanocomposite was successfully synthesized based on FT-IR, BET, XRD, FESEM, EDS element mapping, UV-Vis spectra and TEM analysis. A flow rate of 0.1 L min-1, 0.3 mg min-1 of ozone, 150 ppm of hydrogen peroxide, 45% relative humidity, and 50 ppmv of pollutants were found to be optimal operating conditions. Both pollutants were degraded in excess of 95% under these conditions. For toluene and ethylbenzene, the synergistic of mechanisms effect coefficients were 1.56 and 1.76, respectively. It remained above 95% efficiency 7 times in the hybrid process and had good stability. Photocatalytic-proxone processes were evaluated for stability over 180 min. The remaining ozone levels in the process was insignificant (0.01 mg min-1). The CO2 and CO production in the photocatalytic-proxone process were 58.4, 5.7 ppm for toluene and 53.7, and 5.5 ppm for ethylbenzene respectively. Oxygen gas promoted and nitrogen gas had an inhibitory effect on the effective removal of pollutants. During the pollutants oxidation, various organic intermediates were identified.

Clean environment index: A new approach for litter assessment.

Littered waste is one of the ubiquitous problems in urban environments. In this study, urban environmental pollution was evaluated for the first time using a new developed index. The findings indicated that cigarette butts with an average 58% are the largest share in the composition of littered waste. In addition, the numbers of littered wastes throughout the study area had a spatial variation. According to clean environment index (CEI), the entire study area was found to be in a moderate status. However, 40% of the study areas were classified in a dirty and extremely dirty status. Comparison of the studied urban land-uses showed that residential land use with CEI equal to 3.38 is interpreted in the clean status, while commercial land use with CEI equal to 15.05 can be classified in the dirty status. The application of CEI has a good capability to assess littered waste; this index can be employed to evaluate the pollution of urban sidewalks and other environments such as beaches.

Preparation of a cellulose acetate membrane using cigarette butt recycling and investigation of its efficiency in removing heavy metals from aqueous solution.

This study investigated the recycling of freshly-smoked cigarette butts (FCBs) and unsmoked cigarette filters (UCFs) into a cellulose acetate (CA) membrane. The both samples were prepared by means of a combination of seven cigarette brands, and the phase inversion method was used to recycle each sample into a membrane using N-methyl-2-pyrrolidone. The efficiency of the prepared membranes for the removal of chromium, cadmium, and lead from an aqueous solution in a forward osmosis reactor was investigated. The results showed that the both membranes had a smooth surface and macrovoids. The flux of the prepared membranes from the UCFs and FCBs recycling were 14.8 and 13.2 LMH, respectively. The porosity and reverse salt of the UCFs membrane were 61% and 3.5 gMH, while those for FCBs membrane were 58% and 3.9 gMH. The observed metal removal efficiency of the both membranes was in the range of 85 to 90%. However, increasing the concentration of metals up to five times caused a slight decrease in the removal efficiency (less than 5%).

Upgrading the biogas production from raw landfill leachate using O3/H2O2 pretreatment process: Modeling, optimization and anaerobic digestion performance.

Here, a combined pretreatment oxidation process (O3/H2O2) was investigated to enhance the biodegradability of raw landfill leachate (RLL) and biomethane potential (BMP) in anaerobic reactors. The central composite design (CCD) and response surface methodology (RSM) were employed to optimize the operational parameters influencing on RLL bioavailability in O3/H2O2 process: pH, Oxygen Flow rate, Reaction Time, and H2O2 concentration. The findings revealed that the O3/H2O2 increased biodegradability index (BOD5/COD) of RLL from 0.41 to 0.68 under optimized condition (pH=8, Oxygen flow= 0.25 L.min-1, Reaction Time= 25 min, H2O2 concentration= 2.5 g.L-1). Furthermore, the effects of O3/H2O2 process on BMP of RLL were surveyed under mesophilic anaerobic reactors (Temperature: 37 ± 1 °C) in viewpoints of operational performance and methane yield in a batch mode for incubation period of 24 days. The results showed that O3/H2O2 process simultaneously improve the BMP by 2.99 times higher in a shorter lag-phase period (5 days) compared with control. The pretreatment O3/H2O2 and mesophilic anaerobic digestion process revealed a feasible and efficient method for enhance BMP of RLL.

Synthesis of BiOI@NH2-MIL125(Ti)/Zeolite as a novel MOF and advanced hybrid oxidation process application in benzene removal from polluted air stream.

One of the popular process in volatile organic compounds removal in gas phase is advanced oxidation process. We in this research, synthesized BiOI@NH2-MIL125(Ti)/Zeolite nanocomposite as a novel nanocomposite to degradation of benzene in hybrid advanced oxidation process. The nanocomposite synthesized via solvothermal method. The effect of airflow, ozone gas concentration, hydrogen peroxide concentration, relative humidity and initial benzene concentration are the main parameters in the UV/O3/H2O2/ nanocomposite hybrid process that were studied. The characterization by XRD, FT-IR, FESEM, EDS element mapping, TEM, BET, and UV-vis spectra indicated that nanocomposite were well synthesized. Optimal operating conditions of the process were determined at air flow of 0.1 l/min, ozone concentration of 0.3 mg/min, hydrogen peroxide concentration of 150 ppm, relative humidity of 45 ± 3% and benzene concentration of 50 ppmv. Under these conditions, more than 99% of benzene was degraded. The synergistic effect coefficient of the mechanisms is 1.53. The nanocomposite had good stability in the hybrid process and remained above 99% efficiency up to 5 times. The ozone concentration residual the system was reported to be negligible (0.013 mg/min). The CO and CO2 emissions in the hybrid process was higher than other processes, which indicates better mineralization in the hybrid process. Formaldehyde, octane, noonan, phenol, decanoic acid were reported as the main by-products. The results indicated that UV/O3/H2O2/ nanocomposite hybrid process has fantastic efficiency in the degradation of benzene as one of the indicators of VOCs.

Bio-electrical stimulation process on degradation of Phenanthrene from aqueous solution using a novel anode modified with carbon cloth: Operational performance, microbial activity and energy.

Phenanthrene as the hazardous PAHs-component are extensively detected in industrial wastewater. However, the impacts of bioelectrostimulation process on Phenanthrene degradation in aerobic reactors remained unclear. Here, a novel bioelectrostimulation process equipped with carbon cloth as electrodes was developed to investigate the removal efficiency of Phenanthrene and ATPase enzyme activity in the synthetic wastewater. The results obtained from the present study indicated that a complete Phenanthrene degradation (100%) can be achieved using microbial electrostimulation systems steel mesh coated with carbon cloth (MES-CC) as anode under optimal operational conditions (electrical current: 4 mA, HA concentration: 15 mg L-1) within 18 h. The conductive carbon cloth provides a biofilm carrier to easily transfer the electrons between electrodes and microbial communities. In addition, the highest ATPase enzyme activity (5176 U) was observed when the aerobic MES-CC reactors were operated with electrical current 4 mA. Furthermore, the COD removal efficiency in MES-CC increased from 49% to 96% when the C: N ratio decreased from 20 to 5. The highest value of Vmax in MES-CC for suspended and attached growth were determined to be 2.87 and 0.54 g COD g-1 biomass. Overall, the results demonstrated that MES equipped with carbon cloth and continuous electrical current mode has good potential for efficient Phenanthrene wastewater treatment.