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1.
Heliyon ; 10(1): e23667, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38187256

RESUMEN

Dyes are one of the most common contaminants in industrial effluents, whose continuous release into the environment has become an increasing global concern. In this work, nanoparticles of zero-valent iron (NZVI) were synthesized using the chemical regeneration method ،and were utilized for the first time as a catalyst in the advanced Sono-Nano-Fenton hybrid method for the decomposition of Reactive Red 198 (RR198). The properties of zero-valent iron nanoparticles were analyzed using SEM and XRD. The effect of pH, initial dye concentration, nanoparticle dosage, zero-valent iron and H2O2 concentration on the decomposition efficiency of Red Reactive 198 was investigated. Comparing the efficiency of Reactivate 198 dye degradation in Sonolysis, Sono-NZVI, Sono-H2O2 and Sono-Nano Fenton processes showed that 97 % efficiency was achieved by the Sono-Nano Fenton process in 60 min. The kinetics of the removal process showed that this process follows pseudo-first-order kinetics and the Langmuir-Hinshelwood model. The results indicate that the effectiveness of the ultrasonic process in removing resistant organic pollutants such as dyes increases tremendously with the synergy of the Fenton process.

2.
Int J Biol Macromol ; 185: 66-76, 2021 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-34146560

RESUMEN

In this study calcium alginate-multiwall carbon nanotube (CA/MWCNTs) was synthesized using (CA) calcium alginate and multiwall carbon nanotube (MWCNTs), and its efficiency in adsorption of 4-Nitrophenol (4-NP) in aqueous solution was studied. The structure and properties of the synthesized adsorbent were investigated using scanning electron microscope (SEM), thermal gravimetric analysis (TGA), Fourier transform infrared (FTIR), and X-ray diffraction (XRD). The experimental design was performed using Box-Behnken design (BBD) in which variables pH, CA/MWCNTs, and temperature were examined. The results of the effect of temperature on the removal efficiency of 4-NP showed that the adsorption efficiency decreases with increasing temperature. The results of nonlinear isotherm and kinetics models showed that Langmuir and pseudo-second-order models were more consistent than other models. The maximum adsorption capacity of 4-NP in this study by CA, MWCNTs, and CA/MWCNTs was 136, 168.4, and 58.8 mg/g, respectively, which indicates that the use of MWCNTs on CA could increase the adsorption capacity. The results of reuse of the synthesized adsorbent at 4-NP removal also showed that after 5 reuse of the adsorbent, the removal of 4-NP using CA/MWCNTs is reduced by about 10%, which shows that the synthesized adsorbent can be used several times to adsorb contaminants without significant reduction in the efficiency.


Asunto(s)
Alginatos/síntesis química , Nanotubos de Carbono/química , Nitrofenoles/química , Adsorción , Alginatos/química , Cinética , Microscopía Electrónica de Rastreo , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
3.
J Environ Health Sci Eng ; 17(2): 931-947, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32030164

RESUMEN

BACKGROUND: Azo group dyes are the largest group of synthetics dyes that widely used in industries, especially in textile industry. The presence of these organic compounds in wastewaters and their discharge into environment without efficient treatment may cause adverse effect on human, living and aquatic environment. The purpose of this study was to optimize the adsorption of azo dye of Direct Red 81 (anionic dye) and Basic Blue 41 (cationic dye) from aqueous solution onto magnetic NiFe2O4/RGO nanocomposite. METHODS: In this study the response surface methodology (RSM) based on the central composite design (CCD), was used to optimization and modeling of adsorption process DR81 and BB41 dye on NiFe2O4/RGO. in order to investigating the effect of the operating parameters on the adsorption efficiency DR81 and BB41, four influential factors were chosen that includes of pH (3-9), contact time (5-25 min), adsorbent amount (0.02-0.05 g) and initial dye concentration (40-200 mg/L). A total of 30 experiments were performed for each dye in this study. The concentration of dye in solution was measured by spectrophotometer. The structure of synthesized adsorbent was investigated using Scanning Electron Microscope (SEM), X-ray diffraction (XRD), Fourier transform irradiation (FTIR), transmission electron microscope (TEM) and vibrating sample magnetometer (VSM). RESULTS: Analysis of variance (ANOVA) showed that regression model for both dye adsorption with value of P value <0.001 is significant statistically. The correlation coefficient (R2) for DR81 (R2 = 0.9968) and BB41 (R2 = 0.9948) indicated which there is a good agreement between predicted values and the results of the experiments and the model also well predict the adsorption efficiency. Furthermore, the factors of pH, dye concentration and adsorbent dose, have the greatest effect on adsorption, respectively, while contact time have the lowest effect on adsorption of both dyes. The adsorption behavior of the DR81 and BB41 onto NiFe2O4/RGO was best described by the Langmuir and Freundlich isotherm, respectively. The optimum conditions for maximum removal of DR81 (96.41%) was found to be at pH 3, contact time 19.68 min, adsorbent dose 0.02 g and initial dye concentration 40 mg/L. However, the optimum conditions for maximum removal of BB41 (97.87%) was found to be at pH 9 contact time 18.16 min, adsorbent dose 0.02 g and initial dye concentration 40 mg/L. CONCLUSION: The present study shows that magnetic NiFe2O4/RGO nanocomposite have much potential as a powerful adsorbent for the rapid adsorption of anionic (DR81) and cationic dyes (BB41) from aqueous solution.

4.
J Environ Health Sci Eng ; 17(2): 1163-1169, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32030182

RESUMEN

Daily intake of elements through the consumption of drinking water, due to its detrimental effects, is accounted for an important concern. Although the health risk assessment of heavy metals in different water sources has extensively carried out in various studies, the effect of age and the concentration of all trace elements in drinking tap water have neglected. Therefore, this study was conducted to evaluate the concentrations of heavy metals, e.g., As, Cd, Cr, Ni, Pb, B, Al, Hg, Mn, Zn, Cu, Fe, Se and Ba in the drinking tap water of Zahedan city and to estimate their non-carcinogenic and carcinogenic effects. Moreover, this is the first research in Iran that has also been dedicated to complete investigation on daily intakes of trace elements in tap water. A total of 155 samples of drinking water were randomly taken from the tap water and were analyzed using ICP-OES device. The estimation of the carcinogenic and non-carcinogenic risks of analyzed elements was carried out based on the guidelines of the U.S EPA. The hazard index (HI) values for children and adult age groups were 9.84E-01 and 4.22E-01, respectively. The cumulative Excess Lifetime Cancer Risk (ELCR) for carcinogenic trace elements was in range of tolerable carcinogenic risk 10-6 to10-4 and for all carcinogenic elements were in the order of Pb > Cd > Cr. It also detected that the total carcinogenic risks of the Cd, As and Cr in water samples through the ingestion route are at the levels of "low risk" and "low-medium risk".

5.
Data Brief ; 21: 1409-1414, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30456265

RESUMEN

In this article, the data of heavy metals phytoremediation efficiency were provided. The Azolla was collected from the lake around the Rasht city and washed in tap water, then weighed (0.2, 0.4 and 0.8 g), and kept for 15 days in the 100 ml disposable container in the presence 5, 10 and 25 mg/L of lead, nickel and cadmium ions. The samples were stored in polyethylene containers for analysis of the metal concentration with ICP-OES. According to the results, removal efficiency was increased from 40% to 70% at 10 days along with the increasing of the biomass from 2.0 to 8.0 g. The removal efficiency of Ni (II), Cd (II), and Pb (II) were increased by increasing the contact time up to 10 days. The removal efficiency decreased by increasing of the metals concentration from 5 to 25 mg/L. The highest removal efficiency was observed at heavy metals concentrations of 5 mg/L and contact time of 10 days. Results showed that Azolla had a high potential for the removal of heavy metals from water resources and it can be used in phytoremediation of heavy metals in environmental refinement projects.

6.
Data Brief ; 17: 105-118, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29876379

RESUMEN

This study aimed to determine the parameters of scaling and corrosion potential of drinking water in sources and distribution networks of water supply in two cities of north of Iran. The results of Amlash water sampels analysis in winter revealed that the average values of Langelier, Ryznar, Aggressive, Pockorius, and Larson- skold indices was -1.31, 9.73, 11.5, 9.74 and 0.24, respectively, but, in summer they were -1.51, 10.71, 11.36, 10.72 and 0.25, respectively. For Rudsar, the results of water sampels analysis in winter illustrated that the average values of Langelier, Ryznar, Aggressive, Pockorius, and Larson was -1.12, 9.69, 11.33, 9.19 and 0.16, respectively, while, in summer they were -1.05, 10.04, 11.92, 10.18 and 0.19, respectively. The beneficial of this data is showing the clear image of drinking water quality and can be useful for preventing the economical and safety problems relating to corrosion and scaling of drinking water.

7.
Data Brief ; 18: 1556-1561, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29904656

RESUMEN

Data on this paper describe the concentrations of arsenic, cadmium, copper, nickel, lead and zinc in the surface soils and groundwater's of Kiwi gardens and its relation to chemical fertilizers in Amlash city, Guilan Province, in Iran. The results of this study showed that the average concentration of heavy metals in groundwater and soils of the studied areas was less than the national standards of Iran for irrigation water, Dutch MPA for soils (except Cu and Ni) and Canadian MAC for inorganic fertilizers. Considering that after fertilizing to soils used in gardening, the concentration of heavy metals in groundwater and soil can be increased significantly, so that chemical fertilizers can be considered as an effective factor in increasing the amount of heavy metals in water and soil. The results of this research can be used by who concern about water and soil quality related to fertilizing and also can be used by Rural Water and Wastewater Company and Ministry of Jahad Agriculture of Iran.

8.
Data Brief ; 18: 463-469, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29900202

RESUMEN

The purpose of this study is zoning and determining the concentration of heavy metals including Arsenic (As), Mercury (Hg), Lead (Pb), and Cadmium (Cd) in the groundwater resources of villages located around the Anzali International Wetland. The amount of heavy metals (As, Hg, Pb, and Cd) in the collected samples were determined by the Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) technique. The maximum concentrations of As, Hg, Pb and Cd were 0.216, 0.059, 0.090 and 0.006 mg/L, respectively.

9.
Data Brief ; 18: 1185-1192, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29900292

RESUMEN

In this research heavy metals, Cd and Pb, adsorption efficiency was evaluated in aqueous solutions using live and dead biomass of Pseudomonas aeruginosa bacteria. The various important parameters including; pH, temperature, Cd and Pb concentrations, contact time, live and dead cell mass were examined. First, the resistant P. aeruginosa to heavy metals identified and isolated from contaminated soil. Then, the Minimum Inhibitory Concentration (MIC) of Cd and Pb was determined for P. aeruginosa. The highest adsorption efficiency for Cd and Pb were 87% and 98.5%, under dead cell mass of 125 mg, pH 7, temperature 35 °C and contact time 90 min, respectively. The results of this study showed that P. aeruginosa have a high ability to adsorption of Cd and Pb in aqueous solutions.

10.
Data Brief ; 19: 437-443, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29900339

RESUMEN

The removal of Direct Blue 71 (DB71), by laccase (EC 1.10.3.2, p-bezenediol:dioxygen oxidoreductases) enzyme in presence of 2,2'-Azinobis-(3-ethylbenzothiazoline-6-sulfonate) (ABTS), in aqueous solution was investigated. Data on this article focused on the optimizing and modeling of DB71 removal by Response surface method (RSM) based on Box-Behnken design (BBD), through studying the effective variables as follows: ABTS dose (0.05-0.2 mM), Laccase dose (0.05-0.2 U mL-1), and pH (3-7). The results of experimental showed that laccase was able to removal DB71 with removal percentage of 83% at concentration of 50 mg L-1 after 30 min incubation in presence of ABTS 0.2 mM, at temperature 40 °C and pH 5. The Analysis of Variance (ANOVA) for the predicted quadratic model was done and quadratic equation showed significant R-Squared (0.9969), Adjusted R-Squared (0.9914) and Adequate Precision (49.7). The lack of fit is not significant due to p-value prob > F more than 0.05.

11.
Data Brief ; 18: 80-86, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29896495

RESUMEN

In this article, three variables including laccase dose, 2,2'-Azinobis-(3-ethylbenzothiazoline-6-sulfonate) (ABTS) dose and pH were used to modeling of Direct Red 81 (DR81) elimination from aqueous solutions by laccase-mediated system. Obtained data indicated that the predicted and experimental values were close for DR81 elimination, and the regression was also able to give a good prediction of response for DR81 elimination (R-Squared = 0.9983). From the experimental, the highest elimination of the DR81 was 95. 5% after 30 min incubation at pH 5, temperature 40 °C, ABTS 0.2 mM, and initial concentration of DR81 50 mg L-1 in the presence of 0.2 U mL-1 of the laccase. The data showed that the laccase can be used as a "green" technology for treating of dyes from aqueous solutions. Data analysis was performed using Design-Expert version 7.0.0 (Stat-Ease, trial version).

12.
Data Brief ; 16: 1005-1009, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29322082

RESUMEN

In this research, we measured various parameters related to drinking water quality include turbidity, temperature, pH, EC, TDS, Alkalinity, fecal and total coliform, heterotrophic plate count (HPC), free chlorine, Mn, Ca, Mg, Fe, Na, Cl-, F-, HCO3, in the inlet and outlet of household water treatment devices according to the standard methods for the examination of water and wastewater (W.E. Federation and Association and A.P.H., 2005) [1]. Sixty four inlet and outlet water samples were taken from thirty two household water treatment devices from eight different residential blocks in Golsar town of Rasht, Iran. The data obtained from experiments were analyzed using the software Special Package for Social Sciences (SPSS 24) and MS-Excel.

13.
Data Brief ; 16: 271-275, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29204472

RESUMEN

Data on this paper show the concentrations of COD, BOD5, TSS, K+, Ca2+, Na+, Cl-, [Formula: see text], [Formula: see text], Mn2+, Fe2+, Mg2+, Zn2+, Ni, Pb, Cu and Cd in the influent and effluent of wastewater, and also the nematode eggs, total and fecal coliform in effluents from wastewater treatment plant of Rasht, Guilan Province, in Iran. Measurements of pollutants in influent and effluent was measured according to standard methods (W.E. Federation and Association, A. P. H., 2005) [1]. Statistical analysis of the data was carried out using Special Package for Social Sciences (SPSS 16).

14.
Bull Environ Contam Toxicol ; 94(3): 382-6, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25573278

RESUMEN

A total of 78 street dust samples (75 within city and 3 from suburban) were collected from different areas with various land use within the city of Zahedan in November 2013 at the end of a long dry period. After digestion, the concentrations of Cd, Cr, Cu, Ni, Pb, and Zn were measured by using ICP-OES. The degree of pollution by heavy metals was assessed with respect to the background concentration by calculation and comparison of the pollution index, integrated pollution index (IPI) and enrichment factor (EF). The mean IPI values (aggregate of six heavy metals) in commercial, high traffic, industrial, urban park, and residential were 3.65, 2.76, 1.68, 1.53 and 1.25, respectively. The results of EF analysis showed almost all sampled urban land use types to be enriched in heavy metals compared with sampled background levels, suggesting heavy metals contamination of street dust in the urban center is from anthropogenic sources.


Asunto(s)
Ciudades , Polvo/análisis , Monitoreo del Ambiente/métodos , Contaminación Ambiental/análisis , Metales Pesados/análisis , Monitoreo del Ambiente/estadística & datos numéricos , Irán
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