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•Advanced oxidation processes coupled to ZVI were used to treat micropollutants.•The performance of the technologies was evaluated under oxic and anoxic conditions.•Cells equipped ...with solid polymer electrolyte and diamond electrodes remove efficiently micropollutants.•100% of the drugs from drinking water were photo-electrochemically decontaminated.•Photoelectrolysis coupled to ZVI under anoxic conditions is the most efficient process.
Simultaneous degradation of sulfadiazine, naproxen, diclofenac, ketoprofen and ibuprofen from drinking water was investigated by different technologies including photolysis, electrooxidation, photo-electrooxidation, zero-valent iron and their combinations. All oxidation technologies were very effective for the degradation of all drugs under anoxic conditions and the efficiency decreased under oxic conditions. Results also revealed that all drugs can be photochemically degraded by direct reactions, being ketoprofen and diclofenac completely degraded in only 10 min. Oxidizability with electrooxidation decreases in the sequence sulfadiazine > naproxen > diclofenac > ketoprofen > ibuprofen. Antagonistic effect was observed when photolysis was coupled to electrooxidation for all drugs under anoxic and oxic conditions, except for ibuprofen under O2 bubbling. On the other hand, synergistic effect was observed for ZVI + photolysis, ZVI + electrooxidation for ketoprofen and ibuprofen drugs and ZVI + Photo-electrooxidation for ibuprofen removal. Photo-electrooxidation coupled to ZVI under nitrogen bubbling was found to be the most efficient process.
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•Nanomaterials based single advanced oxidation processes for wastewater treatment.•Nanomaterials based hybrid advanced oxidation processes for wastewater treatment.•Current status of work on hybrid ...nanomaterials as heterogeneous photocatalysts.•Process Intensification of nanostructured materials in waste water oxidation.•Mechanistic aspects of various advanced oxidation processes.
Over the past decades, advanced oxidation processes (AOPs) for wastewater treatment drawn a great deal of attention of the researchers. AOP’s are one of the promising advanced technologies to destroy the total organic content, toxic pollutants etc. from the wastewater. A number of attempts has been made from the past two decades on the waste water treatment using various advanced oxidation treatment techniques. The main objective of this review article is to provide the quick reference for researchers and academicians in the area of wastewater treatment using nanomaterials in conjunction with various AOPs and/or hybrid AOPs. This review article is mainly focused on (1) the nanomaterials-based individual and hybrid AOPs for treatment of various industrial effluents or model effluents, (2) the current status of work in the area of hybrid nanomaterials as heterogeneous catalysts combined with AOPs and hybrid advanced oxidation processes.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
•CO3•− is highly selective for compounds containing aniline, phenolic hydroxyl groups and naphthalene rings.•A good linear relationship is observed between ln(kCO3•−) and the Hammett Σσp+ ...constant.•The formation of CO3•− significantly increases naproxen degradation in UV/NH2Cl but not UV/H2O2, UV/persulfate and UV/Cl2.•The transformation products of naproxen by CO3•− are different from HO•.•The degradation of naproxen by CO3•− does not increase genotoxicity.
The carbonate radical (CO3•−) is a typical secondary radical observed in engineering and natural aquatic systems. This study investigated the degradation kinetics of 20 pharmaceuticals and personal care products (PPCPs) by CO3•− and the transformation pathways of a typical PPCP (naproxen) that is susceptible to CO3•−. CO3•− is highly selective for compounds containing aniline and phenolic hydroxyl groups as well as naphthalene rings, such as sulfamethoxazole, sulfamethazine, salbutamol, propranolol, naproxen, and macrolide antibiotics such as azithromycin, for which the second-order rate constants range from 5.6 × 107 M−1s−1 to 2.96 × 108 M−1s−1. A good linear relationship is observed between the natural logarithms of kCO3•− and the negative values of the Hammett Σσp+ constant for aromatic PPCPs, indicating that electron-donating groups promote the attack of benzene derivatives by CO3•−. The contribution of CO3•− to naproxen degradation is significant in different processes such as UV/H2O2, UV/persulfate, UV/chlorine, and UV/monochloramine, in the presence of HCO3−, which compensates for the decreased contributions of primary radicals. In particular, the formation of CO3•− increases the first-order rate constant of naproxen by 127% in UV/monochloramine in the presence of 50 mM HCO3− compared to that without HCO3−. Natural organic matter (NOM) exerts a slight scavenging effect on CO3•−, decreasing the inhibition effect of NOM on the degradation of naproxen by UV/H2O2 in the presence of HCO3−. The pathways involved in the transformation of naproxen by CO3•− include decarboxylation, hydroxylation, ketonization, demethylation and aldolization. In addition, the alteration of the genotoxicity during naproxen degradation by CO3•− was negligible.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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•Successfully fabricated novel CO32− intercalated Ni/Fe/Zn LDH encapsulated In2S3.•In2S3/LDH is effective in sensing urea and photodegrading pantoprazole.•In2S3/LDH shows better ...sensitivity, selectivity, and reproducibility.•Photocatalytic studies exhibited 98.25 % PTZ degradation in the presence of H2O2.•OH and O2− are the major ROSs for the photodegradation process.
The Ni/Fe/Zn trimetallic LDH intercalated with carbonate ions grown over In2S3 nanoparticles to form a novel In2S3/LDH nanocomposite fabricated with the combined efforts of the solvothermal and in-situ precipitation processes, as well as its enzymatic sensing and visible light-induced degradation ability, were thoroughly investigated in this study. The urease-immobilized In2S3/LDH/ITO electrode showed high-performance electrochemical sensing over a wide range of 1–240 µM with a lower limit of detection (LOD) of 0.246 µM and enhanced sensitivity of 2.29 × 10−7 A μM−1 cm−2 in phosphate buffer solution (50 mM, pH 7.5, 0.9 % NaCl) at a scan rate of 50 mV s−1. The fabricated electrode was reusable for up to 15 scans and demonstrated very high selectivity towards urea, as it showed an insignificant change in current, even in the introduction of various interferences. Furthermore, the synthesized In2S3/LDH nanocomposite demonstrated enhanced photocatalytic ability for degradation of 15 ppm of emerging sulfur-containing pollutant pantoprazole with an impressive efficiency of 98.25 ± 1.51 % in 35 min of visible light irradiation, with a high rate constant of 0.1 min−1. The H2O2-assisted AOP process showed improved COD removal of up to 87.31 ± 1.43 %, with high stability and reusability up to 7 consecutive cycles. Moreover, the as-prepared In2S3/LDH nanocomposite also showed significant degradation of other emerging pollutants with a more than 70 % degradation efficiency. As a result, this composite is a potential electrocatalyst for urea sensors in practical analysis, and it also has outstanding photodegradation of pantoprazole under visible light irradiation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Aspect-oriented software development (AOSD) seeks to renovate the software quality by use of alteration to the design in object-oriented based systems. Each system component has been divided into ...numbers of modules and arranges a design in a way that the module has not crosscut to each other. A module is a collection of block of codes, whose role is to restrict and conceal the design definition. This type of behavior is known as the Separation of Concerns (SoC). AOP helps programmers for separating crosscutting concerns. It can be helpful at better modularizing system, the problem with complex system is that the component require different, crosscutting descriptions at different levels and need maintenance too. In this paper, a study was conducted to analyses quality in aspect-oriented software design. This paper also explores varieties of existing metrics related to AOP also and will discuss in detail with comparison of OOPs using small scale projects that how the new programming paradigm design effects on quality of the software.
In this study, nano-flower WO3 hollow microspheres were synthesized by calcining SrWO4 precursors at 300 °C. The WO3-FeOOH-X series photocatalysts were synthesized by successfully anchoring the ...amorphous FeOOH quantum dots uniformly on the WO3 nanoflower petals. Azo dyes in single system (MB, AR-18) and mixed system (MB+AR-18) were treated synergistically by light and Fenton. The reusability of WO3-FeOOH-3 samples at ambient temperature was investigated. Active species removal experiments were conducted to reveal their photo-Fenton degradation mechanism of organic pollutants. The results showed that the degradation rate of WO3-FeOOH-3 was 98.69% for MB within 5 min. The degradation rate of AR-18 was 92.55%. The mixed dye system (MB+AR-18) became clarified within 5 min. The efficient degradation rate was attributed to the homogeneous dispersion centers and the multiple active sites provided by the WO3 petals for FeOOH anchoring. In conclusion, WO3-FeOOH-X provides a new pathway and applicability for the efficient degradation of MB and AR-18 azo dyes.
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•Zero-dimensional FeOOH quantum dot-modified flower-like WO3 microsphere composites as photo-Fenton catalysts.•WO3-FeOOH-X composites showed enhanced visible light driving surface Fenton efficiency.•Extending the application of WO3-FeOOH-X to simulate real wastewater by using a mixture of MB and AR-18 dyes.•WO3-FeOOH-3 composites showed excellent cycling stability.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Microplastics (MPs) are typically produced via environmental degradation of larger plastics, where they enter the human food chain. MPs are complex materials containing chemical and physical ...characteristics that can potentially affect their hazard and exposure. These physical properties can be altered by environmental exposure potentially altering any risk assessment conducted on the primary material. We conducted a literature review using an Adverse Outcome Pathway (AOP)-based approach from Molecular Initiating Event (MIE) to cell effect event to identify multiple knowledge gaps that affect MPs hazard assessment. There is some convergence of key biological events but could relate to most lying along well-established biological effector pathways such as apoptosis which can respond to many MIEs. In contrast, MIEs of chemicals will be via protein interaction. As MPs may occur in the lumen of the alimentary canal for example to the mucus, therefore, not requiring translocation of MPs across the epithelial membrane. At the other end of the AOP, currently it is not possible to identify a single adverse outcome at the organ level. This work did establish a clear need to understand both external and internal exposure (resulting from translocation) and develop hazard data at both levels to inform on risk assessments.
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•Most toxicity studies on microplastics exposure have focused on polystyrene particles.•It is suggested that PE and PET exposure can lead to lipid metabolism disruption.•Adverse Outcome Pathway for human ingestion of microplastic is suggested.•Risk assessment is still not achievable due to limited data MP ingestion exposure and toxicity in humans.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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•UV activated PMS oxidation is effective for BPA oxidation and mineralization.•BPA degradation rate is not affected by Cl− (5mM), but it is adversely affected by HCO3− and HA.•The ...possible radical adduct formation and degradation pathway are also proposed.•The proposed pathway supports sulfate radical attack as the main route.
In the present study, a sulfate radical-based advanced oxidation process was applied for the degradation of an industrial chemical and suspected endocrine disruptor, Bisphenol A (BPA). UV-C (λ=254nm; 40W power; Io=1.26μEs−1) activated peroxymonosulfate (PMS) was used as an oxidant. The effect of operating parameters (initial concentration of BPA, dose of PMS, initial solution pH (pHo), and water matrix components such as chloride (Cl−), bicarbonate (HCO3−) ions and humic acid (HA) was evaluated. At the initial pH of reaction mixture (5.15) and room temperature (29±3°C), the optimum dosage of PMS was found to be 0.66mM, giving a BPA removal of 96.7±0.05% and a total organic carbon (TOC) removal of 72.5±0.05% after 360min of irradiation. With an increase in initial BPA concentration and PMS dosage greater than 0.66mM, the BPA and TOC removal decreased. The extent of BPA removal increased with an increase in pHo (3⩽pHo⩽12) of the reaction mixture. The degradation of BPA followed pseudo-first-order kinetics and the apparent first order rate constant for BPA was found to be 0.025min−1 at the optimum oxidation conditions (CBPA=0.22mM, CPMS=0.66mM, pH=5.15, temperature=29±3°C). The Cl− ions have negligible inhibition effect on the BPA removal. However, the HCO3− and HA inhibited the BPA oxidation under UV-C irradiation. The identification of intermediates and final products was carried out with HPLC, GC/MS and FTIR, and a degradation pathway was proposed. The present study reveals that the UV-C/PMS oxidation process is effective for BPA removal under real water/wastewater conditions.
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•MnFe2O4@NBC catalysts are synthesized with nitrogen-doped biochar as carrier via the solvothermal method.•MnFe2O4@NBC exhibits excellent performance in activating PMS to remove low ...molecular weight PAHs.•NBC can promote the enhancement of electron transfer and formation of BIEF to enhance the PMS activation.•The degradation of NAP in MnFe2O4@NBC/PMS system is an oxidation process dominated by the free radical pathway.•Fe2+, Mn2+, CO, pyridine nitrogen, and defective structures are important reaction sites for PMS activation.
The conversion of agricultural biomass waste to value-added biochar (BC)-based catalysts receives tremendous interest because it falls under the resource recycle concept. In this work, a magnetic iron–manganese bimetallic catalyst (MnFe2O4@NBC) with nitrogen-doped BC as the carrier was prepared through the solvothermal method using agricultural waste walnut shells as the precursor. Moreover, the structure, morphology, and magnetic separation properties of the catalyst were comprehensively analyzed by various characterization methods. The prepared MnFe2O4@NBC catalyst was coupled with peroxymonosulfate (PMS) for oxidative degradation of naphthalene (NAP). Results showed that MnFe2O4@NBC could effectively activate PMS, and the removal rate of NAP could reach 80.17 % in 120 min. The degradation of NAP through the synergistic action of the free radical pathway (SO4− and OH) and the nonradical pathway (1O2), but the free radical pathway was dominant. XPS, electrochemical profiles, and DFT calculations confirmed that the catalyst surfaces of Fe2+, Mn2+, CO, and pyridine nitrogen and the defective structures are important reaction sites for PMS activation; the synergistic effect of Fe and Mn bimetals promotes the rapid cycling of metal redox pairs, whereas NBC promotes the dispersion of MnFe2O4, the direct activation of PMS, the enhancement of electron transfer, and the formation of a built-in electric field to facilitate the activation process. The catalysts showed a decrease in the removal of NAP after three times of reuse, but their activity could be restored by simple heat treatment, thus showing great potential for application. In brief, this work provides an efficient MnFe2O4@NBC heterogeneous catalyst and a new insight into PMS activation, which extends the potential application of BC-based catalysts for environmental remediation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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•Cerium vanadate nanostructures was prepared by simple one-pot co-precipitation method.•The nanostructures resulted in complete degradation of 100 ppm phenol in 80 min via activation ...of PMS.•The degradation followed a pseudo-first-order kinetics model with high R2 value and low activation energy of 23.74 kJ/mol.•The nanostructures were tested for recyclability up to 5 cycles and displayed excellent recyclability and reusability.•The mechanistic study revealed that non radical pathway via 1O2 mediated activation of PMS govern the catalytic activity.
In this study, a nanostructured CeVO4 material was synthesized using a simple co-precipitation technique and investigated as a catalyst for phenol degradation via peroxymonosulfate (PMS) activation. The structural and morphological properties of the CeVO4 catalyst were characterized using XRD, XPS, FTIR, Raman spectroscopy, TGA, SEM, and TEM. The results indicated that the prepared catalyst exhibited a pure crystalline phase with a rod-like structure. The CeVO4 catalyst exhibited high activity towards PMS activation, resulting in complete degradation of phenol within the first 80 min at room temperature. The degradation reaction was found to follow pseudo-first-order kinetics with a low activation energy of 23.74 kJ/mol. The degradation followed a catalytic surface-mediated electron transfer route as confirmed using ESR measurements. The effects of several experimental parameters on phenol degradation were investigated, including the catalyst loading, initial phenol concentration, PMS dosage, reaction temperature, and pH. The regeneration and reusability of the CeVO4 catalyst were also examined for 5 consecutive cycles. This study puts forward CeVO4 as a heterogeneous catalyst for the complete removal of persistent organic pollutants via PMS activation, indicating a favorable application in wastewater treatment.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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