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1.
Heliyon ; 9(10): e20880, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37876429

RESUMO

Diazinon (DIZ) and 4-Chloro-2-methylphenoxyacetic acid (MCPA) herbicide and widely used in agricultural lands. Present study investigates diazinon and 4-chloro-2-methylphenoxyacetic acid photo-reduction via UV/Sulfite (US) in as Advanced Reduction Processes (ARP). The ideal pH was Molar ratio of sulfite: DIZ or MCPA 1:1 and, 20 min reaction time, and pH 9, in which about 100 % reduction of DIZ and MCPA with a concentration of 10 mg L-1 was achieved and the optimal conditions were considered. Kinetic investigation increasing DIZ and MCPA concentration from 5 to 20 mgL-1, kobs increase about from 0.151 to 0.234 for DIZ and from 0.231 to 0.589 min-1. Also, reaction rate (robs) increases about from 0.755 to 4.68 for DIZ and from 1.155 to 11.78 mg L-1.min. The amount of energy consumption in DIZ solution increased from 5 to 20, respectively, from 0.73 to 2.37, and in the reduction of MCPA from 0.47 to 1.49 kWh per cubic meter. According to experiments performed in 30 min with the US process, COD levels were reduced by about 46 % of both pollutants. It is important to note that the BOD/COD ratio rose from about 0.20 to 0.48 after 30 min. Since the index of biodegradability has grown high, it can be concluded that non-biodegradable COD (NBDCOD) convert to biodegradable COD (BDCOD) and toxicity is lower than of before of treatment. This study has been very suggesting that the UV/sulfite method produces effluent with a non-toxic and ecologically beneficial manner by biological treatment or discharge directly in environment.

2.
Environ Sci Pollut Res Int ; 30(6): 14630-14640, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36161559

RESUMO

In this study, simultaneous removal of an organic matter (diazinon, DIZ) and an inorganic substance (chromium, Cr) was used. Breaking down of organic matter by UV irradiation produces various radicals, including sulfides, carboxyl, hydroxyl, hydrated electrons, and various organic radicals that are highly reactive and help us to precipitation inorganic substance (Cr). The optimal condition was 30:1 DIZ:Cr molar ratio, pH 9, and about 100% and 82.3% of DIZ and Cr were obtained in 30 min. Cr deposition was very slow at first. After the destruction of the DIZ structure, Cr deposition began, and various types of sludge with disturbed properties were formed. These sledges were analyzed by FTIR analysis and showed that green sludge could be chromium (III) hydroxide; brown sludge due to chromium (III) hydroxide, tiny green crystals from chromium (III) oxide, red brick from chromium (II) acetate chromium trioxide, as well as black sludge caused by chromium oxide were identified. In UV/DIZ/Cr process, kobs and robs range obtained 0.33-0.15 and 16.8-23.4 $ with both Cr and DIZ concentration increased from 50 to 150 mg L-1. Also, EEO for Cr precipitation was 24.65 to 5.74 and for DIZ 12.54 to 4.73 (kwh m-3). Depending on the amount of energy consumption, TCS was 37.19 to 10.47 for Cr precipitation and 4.46 to 1.25 $. It is important to note that when both pollutants are exposed to ultraviolet light, more energy and cost are generally required from UV/DIZ process and less than of UV/Cr process. But it should be noted that in fact 50 mg L-1 of chromium and 50 mg L-1 of DIZ are being removed at the same time. In UV/DIZ and UV/Cr processes that are exposed to ultraviolet radiation alone, only one of them is removed. Also, when these two pollutants are being removed at the same time, the total amount of energy is much less than the total energy consumption of the pollutants one by one.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Esgotos/química , Fotólise , Diazinon , Raios Ultravioleta , Oxirredução , Cromo/química , Poluentes Ambientais/análise , Poluentes Químicos da Água/análise
3.
Environ Sci Pollut Res Int ; 29(43): 64914-64923, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35476267

RESUMO

Regarding the cost-effective photo-degradation of ofloxacin (OFL), present study investigates UV/sulfite /ZnO (USZ) in reactor conventional (without baffles) and baffled photocatalytic reactor (BPCR). The optimal condition was 0.77:2:50 sulfite/ZnO/OFL molar ratio, pH 7, and 30 min reaction time for 100% degradation of 200 mg L-1 concentration of OFL. As information obtained, the UZI process reduces the BOD and COD level about 66% to 86.29% within 80 min reaction, respectively. Also, BOD/COD ratio initial from 0.26 reaches 0.6 after 30 min of reaction time. Kinetic investigation increasing OFL concentration, kobs and robs increase, and, secondly, in the conventional and BPCR reactor, kobs increase is about 17% and 50% with increasing OFL concentration from 50 to 200 mgL-1. Also, figure-of-merit EEo varies from 12.66 to 17.41 and 7.26 to 10.15 kWhm3 for conventional reactor and 8.66-13.61 to 5.24-8.12 kWhm3, respectively. Also, kinetic model EEo declines from 15.23 to 8.61 and from 13.31 to 5.37 kWh m-3 in conventional and BPCR, respectively. Total cost of the system (TCS) decreases from 7.31 to 2.16 $ in conventional reactor and 4.57 to 0.55 $ in PCBR reactor. Total cost of the system (TCS) was investigated at different concentrations.


Assuntos
Poluentes Químicos da Água , Óxido de Zinco , Cinética , Ofloxacino , Sulfitos
4.
Environ Sci Pollut Res Int ; 29(38): 58078-58087, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35362886

RESUMO

Regarding the cost-effective degradation of diazinon (DIZ), the present study was conducted to develop and UV/iodide process in a photo catalyst reactor. CCD modeling applied and the results shows that the highest R-squared value (adjusted R-squared: 0.9987), the lowest P-value (2.842 e - 10), the lowest AIC (14.54), and the most insignificant lack-of-fit (0.73) belonged to the second-order model. Based on second-order model, the stationary points for time, iodide: DIZ (molar ratio %), DIZ concentration, and pH were 6.99 min, 80.15% iodide: DIZ (molar ratio %), 3.34, mg L-1, and pH 7.34 (- log10[H+]), respectively. The maximum reduction efficiency of 97.22% was obtained at the experimental conditions. The LC-MS analyses from optimal condition implied that all the DIZ molecules and its intermediates breaking to simple compounds during 15 min of processing. The data shown UI process reduced the BOD and COD levels by about 66% and 86.29% within 80 min of photoreaction, respectively. Furthermore, in kinetic investigation, with the increase in DIZ concentration, kobs and robs increased and secondly, the conventional and PCBR reactor kobs increased by about respectively 17% and 50% with an increase in DIZ concentration from 5 to 15 mgL-1. Additionally, when the DIZ concentration increase from 5 to 15 mg L-1, robs increased in the conventional and PCBR reactors respectively about 4.9 and 6 times. Figure-of-merit EEo changed from 12.66-17.41 to 7.26-10.15 kWhm3 for the conventional reactor, and 8.66-13.61 to 5.24-8.12 kWhm3 in PCBR, when the DIZ concentration increasing from 5 to 15 mg L-1. Consequently, in the PCBR reactor, the energy consumption reduced by 14% at 5 mg L-1 DIZ concentration and by 60% at 15 mg L-1 DIZ concentration. Also, total cost of the system (TCS) decreases from 4.52 to 1.46 $ in conventional reactor and 1.47 to 0.42 $ in PCBR reactor when the DIZ concentration increase from 5 to 15 mg L-1.


Assuntos
Praguicidas , Poluentes Químicos da Água , Diazinon , Iodetos , Raios Ultravioleta , Poluentes Químicos da Água/química
5.
J Hazard Mater ; 377: 418-426, 2019 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-31176077

RESUMO

The aim of this study is to develop the process relies on the UV irradiation of ZnO and I-, i.e. UV/ZnO /I- (UZI), to create both oxidizer and reducer agents simultaneously for photo-degradation of the Ciprofloxacin (CIP). This paper shows that while applying UV irradiation, UV/ZnO and UV/I- for 20 min can lead to achieve 37.5%, 58.12%, and 61.4% photo-degradation of 100 mg L-1 CIP at pH 7, respectively. Moreover, the UZI treatment can provide 91.54% photo-degradation efficiency. The LC-MS analysis of the UZI effluent indicates that 10 min process was adequate to degrade CIP into simple ring-shaped metabolites while 15 min treatment, mostly of CIP intermediates were linear and biodegradable organic compounds. Furthermore, fourteen little fragments were identified in the CIP photo-degradation via UZI, during the photoreaction time of 2.5 to 20 min. Then, a pseudo first-order kinetics equation was utilized to model the observed photo-degradation process. Finally, the computational results show that the increased concentration of the CIP solution from 100 to 400 mg L-1 decreases the observed rate constant (kobs) from 0.4125 to 0.2189 min-1 while increases the photoreaction rate (robs) from 41.25 to 87.56 mg L-1 min-1.


Assuntos
Ciprofloxacina/química , Ciprofloxacina/efeitos da radiação , Processos Fotoquímicos , Algoritmos , Análise da Demanda Biológica de Oxigênio , Catálise , Custos e Análise de Custo , Sequestradores de Radicais Livres , Radical Hidroxila , Iodetos , Cinética , Substâncias Redutoras , Raios Ultravioleta , Poluentes Químicos da Água/química , Óxido de Zinco
6.
Data Brief ; 17: 731-738, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29876430

RESUMO

This dataset deals with the modification of granular activated carbon (GAC) with FeCl3 under basic conditions (pH ≈ 12) for removal of aluminium (Al) from aqueous solution. The structural properties and operational parameters including Al ion concentration (2.15 and 10.3 mg/L), pH solution (2-10), adsorbent dosage (0.1-5 g/L), and contact time (0-10 h) was investigated for raw and modified GAC. This dataset provides information about Al removal by GAC and modified GAC at conditions including: pH = 8, contact time = 6 h, initial Al concentration = 2.15 mg/L. The characterization data of the adsorbents was analysed by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and Brunauer, Emmett and Teller (BET) test. The data showed that Freundlich isotherm with and Pseudo second order kinetic model were the best models for describing the Al adsorption reactions. The acquired data indicated that the maximum adsorption capacity of GAC and modified GAC to uptake Al (C0 = 10.3 mg/L) was 3 and 4.37 mg/g respectively.

7.
Data Brief ; 15: 916-921, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29159230

RESUMO

During operation of most water treatment plants, spent filter backwash water (SFBW) is generated, which accounts about 2-10% of the total plant production. By increasing world population and water shortage in many countries, SFBW can be used as a permanent water source until the water treatment plant is working. This data article reports the practical method being used for water reuse from SFBW through different method including pre-sedimentation, coagulation and flocculation, second clarification, ultra filtration (UF) and returned settled SFBW to the beginning of water treatment plant (WTP). Also, two coagulants of polyaluminum ferric chloride (PAFCl) and ferric chloride (FeCl3) were investigated with respect to their performance on treated SFBW quality. Samples were collected from Isfahan's WTP in Iran during spring and summer season. The acquired data indicated that drinkable water can be produced form SFBW by applying hybrid coagulation-UF process (especially when PAFCl used as coagulant).

8.
Asian Pac J Cancer Prev ; 18(5): 1389-1394, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28612592

RESUMO

Despite documented successful Pap tests in routine care of women, screening levels are unfortunately often lower than recommended. This study aimed to assess differences in adherence to Pap test guidelines among a sample of Iranian women using the Health Belief Model (HBM). In this descriptive and analytical study, information was collected from a total of 305 women, (age range of 15-49) from Zarandieh health centers in Iran using a random multistage sampling method. The questionnaire covered demographic characteristics; health belief model constructs were gathered by a self-report method. The results were analyzed using the independent samples t test and logistic regression in SPSS-20. A total 32% of the subjects had a history of a Pap test and the score mean of the whole constructs model (knowledge, susceptibility, severity, benefits, barriers and self-efficacy) in these individuals was higher than those without a positive history. Among the predictive variables of HBM constructs, the highest weights were observed for perceived benefits ß)=0.36), perceived susceptibility =ß) 0.35) and self-efficacy ß)=0.29). Based on our finding of positive relationships for health belief model structures with performance of a pap smear test, designing educational interventions for changing the knowledge levels and beliefs of women is recommended.

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