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While phytoremediation has been widely employed for greywater treatment, this system suffers from the transfer of considerable amounts of surfactants to the aquatic environment through partially treated effluent and/or exhausted plant disposal. Hence, this study focuses on greywater phytoremediation followed by recycling the spent plant for preparing an adsorbent material used as post-treatment. P. crassipes was used to operate a phytoremediation unit under 23 °C, 60% relative humidity, plant density (5-30 g/L), dilution (0-50%), pH (4-10), and retention time (3-15 days). The optimum condition was 12.7 g/L density, 34.0% dilution, pH 8.4, and 13 days, giving chemical oxygen demand (COD), surfactant, and NH4-N removal efficiencies of 94.62%, 90.45%, and 88.09%, respectively. The exhausted plant was then thermally treated at 550 °C and 40 min to obtain biochar used as adsorbent to treat the phytoremediation effluent. The optimum adsorption process was biochar dosage of 1.51 g/L, pH of 2.1, and 137 min, providing a surfactant removal efficiency of 92.56%. The final discharge of this phytoremediation/adsorption combined process contained 8.30 mg/L COD, 0.23 mg/L surfactant, and 0.94 mg/L NH4+-N. Interestingly, this approach could be economically feasible with a payback period of 6.5 years, 14 USD net present value, and 8.6% internal rate of return.
The research succeeded in treating greywater by phytoremediation followed by recycling the exhausted P. crassipes plant to prepare an adsorbent material used in the post-treatment phase, giving an economically feasible scenario with 6.5-year payback period.
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Sulfur recovery units (SRU) have an important role in the industrial production of elemental sulfur from hydrogen sulfide, whereas the generated acidic gas emissions must be controlled and treated based on local and international environmental regulations. Herein, Aspen HYSYS V.11 with Sulsim software is used to simulate the industrial and treatment processes in a refinery plant in the Middle East. In the simulation models, in temperature, pressure, flow, energy, and gas emissions were monitored to predict any expected change that could occur during the industrial processes. The simulation models were validated by comparing the obtained data with actual industrial data, and the results showed low deviation values. The simulation results showed that the current process temperature conditions can work efficiently for sulfur production without causing any environmental consequences. Interestingly, the simulation results revealed that sulfur can be produced under the optimized temperature conditions (20° less than design temperatures) with a total amount of steam reduction by 1040.12 kg/h and without any negative impact on the environment. The steam reduction could have a great economic return, where an average cost of 7.6 $ per ton could be saved with a total estimated cost savings by 69,247.03 $ per year. The simulation revealed an inaccurate production capacity calculated by real data in the plant during the performance test guarantee (PTG) where the real data achieved around 1 ton/h higher capacity than the simulation result, with an overall recovery efficiency of 99.96%. Based on this significant result, a solution was raised, and the level transmitters were calibrated, then the test was repeated. The simulation models could be very useful for engineers to investigate and optimize the reaction conditions during the industrial process in sulfur production facilities. Hence, the engineers can utilize these models to recognize any potential problem, thereby providing effective and fast solutions. Additionally, the simulation models could participate in assessing the performance test guarantee (PTG) calculations provided by the contractor.
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Sulfeto de Hidrogênio , Vapor , Monitoramento Ambiental , Enxofre , Oriente MédioRESUMO
As Diphenhydramine (DPH) has been considered as a drug to treat SARS-CoV-2, the degradation of DPH from water was investigated and evaluated in this study by adopting an advanced oxidation/advanced reduction process - the UV/sulfite process. The UV/sulfite system was able to eliminate DPH within 6 mins under UV254nm and 1.0 mM sulfite. It was observed that the presence of N O 3 - , N O 2 - , C l - , H C O 3 - , and S O 4 2 - anions in water can affect the performance of UV/Sulfite degradation system. The mechanism of UV/sulfite/anions was evaluated which the presence of N O 3 - in UV/sulfite process has revealed faster initial decay rate but lower final DPH removal. It was observed that the UV/Sulfite process was extremely sensitive to pH as the dissociation of ion species varied among pH. The reaction became sluggish in acidic solution due to the dissociation of less reactive species such as HSO3 -. In alkaline solution, SO3 2- was the dominant species, producing powerful SO 3 â - and e aq - when activated by UV at 254 nm. By conducting LC/MS analysis, the degradation pathway was proposed and can be summarized into four main pathways: hydroxylation, side chain cleavage, losing aromatic ring or ring opening. Scavenging tests were also carried out and validated the presence of various radicals contributing to the reaction, including e aq - , HË, OHË, SO3 Ë-, O2 â¢- and SO4 Ë-.
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VEGFR-2 is a key regulator in cancer angiogenesis. This research displays the design and synthesis of novel 3-cyano-6-naphthylpyridine scaffold-based derivatives as selective VEGFR-2 inhibitors and cytotoxic agents. In vitro percent kinase activity inhibition screening against a panel of 23 kinases at a single high dose (30 nM) affirmed that VEGFR-2 was selectively the most responsive to inhibition by the investigated chemotypes. IC50 values determination demonstrated kinase inhibitory activities of the test compounds at the sub-nanomolar level. In vitro testing of the new compounds against two prostate cancer cell lines namely PC3 and DU145 and two breast cancer cell lines namely MCF-7 and MDA-MB435 confirmed their potent cytotoxic activity with IC50s at the nanomolar level. The most active compound against MCF-7 viz.11d was subjected to an in vivo examination against a xenograft mouse model and was found effective. Studying the tissue mRNA expression levels of various cell cycle controlling biomolecules in 11d-treated MCF-7 cells demonstrated (i) upregulation of p53, p21 and p27, (ii) cleavage of PARP protein, (iii) activation of caspase-3, -8 and -9, (iv) downregulation of the anti-apoptotic protein Bcl, (v) upregulation of the pro-apoptotic protein Bax, and (vi) decreased expression of Cdks 2, 4, 6 and cyclin D1. Additionally, 11d affected a cell cycle arrest at the G1 phase in treated MCF-7 cells and an S phase arrest in MCF-7 p53 knockdown cells. Additionally, molecular docking was performed to predict how 11d might bind to its biological target VEGFR-2. Finally, in-silico ADME and drug-likeness profiling of these derivatives demonstrated favorable properties thereof.
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Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Piridinas/uso terapêutico , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Animais , Antineoplásicos/síntese química , Antineoplásicos/metabolismo , Antineoplásicos/farmacocinética , Domínio Catalítico , Linhagem Celular Tumoral , Feminino , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Humanos , Camundongos Nus , Simulação de Acoplamento Molecular , Estrutura Molecular , Ligação Proteica , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/metabolismo , Inibidores de Proteínas Quinases/farmacocinética , Piridinas/síntese química , Piridinas/metabolismo , Piridinas/farmacocinética , Relação Estrutura-Atividade , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/química , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Herein, a novel nitrogen-doped ZnO photocatalyst supported on biochar (N-ZnO@LBC) was synthesized using the Lantana camera as a green source of biochar. The synthesized photocatalyst was applied as an activator of persulfate (PS) for the photodegradation of methylene blue (MB) under visible light irradiation. The properties of the synthesized photocatalyst were explored before and after photocatalysis using different characterization analyses. The results revealed that the nitrogen doping of ZnO@LBC could reduce the band gap energy from 2.83 eV to 2.78 eV resulting in higher activity under visible light. The synergetic effect of the N-ZnO@LBC/PS/visible process was investigated under various reaction conditions. Surprisingly, about 95.7% of MB photodegradation could be achieved using N-ZnO@LBC/PS/visible process under optimal conditions. Moreover, a prediction model with an excellent correlation between the actual and predicted data (R2 = 0.9844) was established to forecast MB removal. Interestingly, the scavenging tests exhibited that various reactive species could induce MB degradation in an order of O2-⢠> h+ > SO4-⢠>â¢OH with the highest contribution of O2-â¢. Additionally, the presence of functional hydroxyl groups in the N-ZnO@LBC structure could lead to the generation of additional radicals as confirmed by FT-IR analysis after photocatalysis. The reusability test showed that the photocatalyst could be reused for up to five cycles without a significant loss in the photocatalytic activity indicating its high stability. The cost of wastewater treatment by N-ZnO@LBC/PS/Visible process was estimated to be US$ 9.79/m3 based on an economic analysis. It worth mentioning that the proposed process was investigated for the degradation of other dyes including Congo red (CR) and methyl orange (MO) and the efficiencies were 65.41% and 59.23% for CR and MO, respectively. Overall, the proposed process could be a promising and cost-effective approach for the degradation of various dyes in real applications.
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Lantana , Óxido de Zinco , Espectroscopia de Infravermelho com Transformada de Fourier , Luz , Corantes , Vermelho Congo , Azul de Metileno , NitrogênioRESUMO
Herein, we explore the holistic integration of magnetite-based photocatalysts and techno-economic analysis (TEA) as a sustainable approach in wastewater treatment aligned with the Sustainable Development Goals (SDGs). While considerable attention has been devoted to photocatalytic dye degradation, the nexus between these processes and techno-economic considerations remains relatively unexplored. The review comprehensively examines the fundamental characteristics of magnetite-based photocatalysts, encompassing synthesis methods, composition, and unique properties. It investigates their efficacy in photocatalytic degradation, addressing homogeneous and heterogeneous aspects while discussing strategies to optimize photodegradation efficiency, including curbing electron-hole recombination and mitigating scavenging effects and interference by ions and humic acid. Moreover, the management aspects of magnetite-based photocatalysts are examined, focusing on their reusability and regeneration post-dye removal, along with the potential for reusing treated wastewater in relevant industrial applications. From a techno-economic perspective, the study evaluates the financial feasibility of deploying magnetite-based photocatalysts in wastewater treatment, correlating reduced pollution and the marketing of treated water with social, economic, and environmental objectives. By advocating the integration of magnetite-based photocatalysts and TEA, this paper contributes insights into scalable and profitable sustainable wastewater treatment practices. It underscores the alignment of these practices with SDGs, emphasizing a comprehensive and holistic approach to managing wastewater in ways that meet environmental, economic, and societal objectives.
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The presence of a wastewater treatment plant in the Arab El-Madabegh region, which discharges excessive amounts of raw effluent toward the nearby farming fields, is the area's main issue. Examining the harmful implications of raw effluent releases on groundwater quality, determining if treated wastewater effluent complies with regulations for discharge into the aquatic environment, and assessing irrigation appropriateness by the effluent are the main goals of this work. In order to accomplish these targets, twelve treated effluent samples from the Arab El-Madabegh wastewater treatment plant were gathered every two weeks starting in January 2012 and finishing in June 2012. They were tested to determine pH, Total Dissolved Solids (TDS), Total Suspended Solids (TSS), Temperature (Temp), Conductivity (EC), Turbidity (Turb.), Chemical Oxygen Demand (COD), Biological Oxygen Demand (BOD), Total Organic Carbon (TOC), NO3-, SO42-, Cl-, Ca2+, PO43-, HCO3-, Na+, Mg2+, and heavy metals such as (Fe, Mn, K+, Cr, Pb, Zn, Ni, Cu, and Cd). The outcomes revealed that all Egyptian and Food and Agricultural Organization (FAO) standards for unrestricted irrigation were met by the treated effluents, except for COD, which exceeded than the Egyptian allowed limit. The evaluation indices of the effluent's EC, SAR, PI, MR, and MH were in the low-risk category according to indicators of water quality for irrigation, nevertheless, The SSP and RSC both showed slightly higher values (67.9% and 2.76, respectively). As well, The average values of heavy metals in treated wastewater effluent were found to be below permitted limits, with the exception of lead and phosphate, which exceeded permissible limits in Egypt. The environmental sustainability (ecological friendliness) of reusing and recycling tertiary treated wastewater can be achieved in agriculture to reduce the adverse impacts on the aquatic environment.
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Árabes , Metais Pesados , Humanos , Egito , Águas Residuárias , AgriculturaRESUMO
This study focuses on upcycling cement kiln dust (CKD) as an industrial waste by utilizing the undissolved portion (UNP) as a multicomponent catalyst for bioethylene production from bioethanol, offering an environmentally sustainable solution. To maximize UNP utilization, CKD was dissolved in nitric acid, followed by calcination at 500 °C for 3 h in an oxygen atmosphere. Various characterization techniques confirmed that UNP comprises five different compounds with nanocrystalline particles exhibiting an average crystal size of 47.53 nm. The UNP catalyst exhibited a promising bioethylene yield (77.1%) and selectivity (92%) at 400 °C, showcasing its effectiveness in converting bioethanol to bioethylene with outstanding properties. This exceptional performance can be attributed to its distinctive structural characteristics, including a high surface area and multiple-strength acidic sites that facilitate the reaction mechanism. Moreover, the UNP catalyst displayed remarkable stability and durability, positioning it as a strong candidate for industrial applications in bioethylene production. This research underscores the importance of waste reduction in the cement industry and offers a sustainable path toward a greener future.
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Pyrite (FeS2) is an abundant sulfide-associated iron mineral that exists in the earth. In this study, the pyrite/oxone process was demonstrated to be an effective approach for the catalytic degradation of propanil, where more than 90% decay ([propanil]0 = 0.01 mM) was achieved within 15 min. Typically, the effects of various experimental parameters, including catalyst loading, oxone dosage, propanil concentration, and initial solution pH, were examined. Two optimal reaction pH values were observed at pH 9.1 and pH 2.9. The generated SO4ï¼ and OH were verified to be the dominant reactive radicals and primarily responsible for the propanil degradation. Both Fe(II) regeneration and sulfur conversion play an important role in oxone activation mechanism and effectively aid the catalytic activity of pyrite. Different co-existing natural water constituents exert dissimilar effects on the pyrite/oxone process. Additionally, the reusability test of pyrite exhibited a reasonable catalytic activity. The pyrite/oxone process was proven efficient in terms of propanil mineralization. A series of reaction intermediates was detected via four major degradation pathways. Overall, the pyrite/oxone process could be a promising approach for the removal of organic compounds in water.
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Sulfite-based photocatalysis has been recently employed as a promising technology for the treatment of organic pollutants via the generation of reactive radicals. In this contribution, the effect of wastewater matrix constituents and toxicity evaluation were systematically investigated in the FeIII impregnated N-doped TiO2 (FeN-TiO2)/sulfite/visible LED (Vis LED) process in the presence of diphenamid (DPA) as a model organic pollutant. The results showed that the presence of HCO3-, SO42-, NO3-, and F- had no detrimental effect on DPA degradation. Conversely, the presence of Cr(VI), NO2-, Cl-, and Br- caused a stronger retardation effect. The effect of natural organic matter such as humic acid (HA) was inert at normal concentrations. Interestingly, the retardation effect of inorganic ions can be quantified at any given ion concentration based on the linear correlations between the DPA decay (first-order kinetic constants) and concentration of ion species. Toxicity tests on Synechocystis sp., Microcystis flos-aquae, and Nostoc sp. algae revealed that higher toxicity was noticed at 240 min treatment time accompanied by lower toxicity with prolonging the treatment time for all selected algae except for Microcystis flos-aquae. In addition, novel two-phase mathematical models were successfully proposed to predict the accumulation of intermediates depending on their evolution profile.
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Ácidos Difenilacéticos/química , Poluentes Químicos da Água/química , Ácidos Difenilacéticos/toxicidade , Compostos Férricos , Substâncias Húmicas , Cinética , Microcystis , Fotólise , Sulfitos , Titânio , Águas Residuárias/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidadeRESUMO
A hybrid process was proposed for carbofuran (CBF) degradation, a carbamate pesticide with a special refractory property, through peroxymonosulfate (PMS) activation under visible LED (Vis LED) by FeIII impregnated N-doped TiO2 photocatalyst (FeNT). An in-depth investigation was conducted to examine the synergistic effect of the FeNT/PMS/Vis LED process under various reaction conditions. An increase in the rate constant was observed with the increment of pH from 2.4 to 7.4, implying the feasibility of the process at neutral pH. A further increase in pH from 8.9 to 11 showed a sudden drop in the rate constant (if the role of base activation is ignored). The efficiency of CBF degradation is still more than 70% after adding NO3-, SO42-, HCO3-, and Cl-. Interestingly, the efficiency was not influenced even after the further increment of nitrate concentration. Furthermore, the high chloride concentrations caused an enhanced efficiency due to the generation of reactive halogens through two-electron transfer. Sixteen major intermediates were recognized and eight of them were never reported in the previous studies. Surprisingly, a new degradation pathway was noted in this study via H-abstractions and cyclization mechanisms. The FeNT/PMS/Vis LED process exhibited a dual functionality in terms of mineralization efficiency and about 90% TOC reduction can be achieved. Therefore, these findings provide new insights into the mechanism of PMS activation under Vis LED after coupling non-metal doped TiO2 photocatalyst with a metal component, and its implications for degradation of refractory and non-biodegradable pollutants in wastewater.
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Carbofurano/química , Peróxidos/química , Poluentes Químicos da Água/química , Compostos Férricos , Águas Residuárias , Poluentes Químicos da Água/análiseRESUMO
Photodegradation of 4-chlorophenoxyacetic acid (4-CPA) was systematically investigated using N-doped TiO2 (N-TiO2) under commercially available visible light emitting diode (Vis LED) as a novel Vis LED illumination in photocatalysis applications. The synergetic effect of Vis LED/N-TiO2 process was studied in detail by varying reaction conditions including the initial concentration of 4-CPA, catalyst dosage, light intensity, and initial pH. Additionally, the influence of inorganic anions and radical scavengers on the performance of the Vis LED/N-TiO2 process was also evaluated. The Vis LED/N-TiO2 was found to be a promising process in terms of mineralization of 4-CPA. It is interesting to note that the performance of this process was not reduced after successive usage of the recycled catalyst; instead, the reaction rate of 4-CPA decay actually increased by using the spent catalyst. The mechanism behind rate enhancement after/during reuse was explored by XPS and FT-IR analyses and it was proven that hydroxyl groups can be incorporated into the catalyst surface by the repeated wetting of N-TiO2 after each reuse. This facilitates the formation of hydrogen bonds between the 4-CPA molecules and N-TiO2, thereby allowing more collisions between the trapped 4-CPA and radicals at the interface of bulk solution and catalyst, respectively.