15 research outputs found

    The effect study of Acetic acid on the scoria performance in removing of Malachite from aquatic environments: Determination of model, isotherms and reaction kinetics

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    زمینه و هدف: رنگ مالاشیت به دلیل ویژگی های ساختاری قابلیت تجزیه بسیار کمی داشته و موجب ایجاد مشکل در محیط های آبی می شود. با توجه به تأثیر اسید استیک بر ویژگی های فیزیکی و شیمیایی اسکوریا، هدف از این مطالعه بررسی کارایی فرم های مختلف اصلاح شده اسکوریا با اسید استیک در حذف رنگ مالاشیت از محیط های آبی می باشد. روش بررسی: این مطالعه آزمایشگاهی بوده که در pH، دوز جاذب، زمان های تماس مختلف و غلظت ثابت رنگ انجام شد. سپس غلظت باقیمانده در محلول رنگ از طریق جذب به وسیله اسپکتروفتومتر در طول موج 665 نانومتر اندازه گیری شد. به منظور درک چگونگی جذب، داده های به دست آمده با ایزوترم های جذب لانگمیر، فروندلیچ و سینتیک های واکنش شبه درجه اول و دوم برازش داده شدند. برای تحلیل داده ها از نرم افزار DOE= Design of Experiments)) استفاده شد. یافته ها: نتایج نشان داد که با افزایش نرمالیته اسید، pH، دوز جاذب و زمان تماس، کارایی جاذب در حذف رنگ افزایش می یابد، به طوری که بیشترین راندمان حذف (100) برای جاذب اصلاح شده با اسید استیک 12 نرمال در 11 =pH، دوز جاذب 4/1 گرم در لیتر و زمان 75 دقیقه به دست آمد. همچنین جذب رنگ از هر دو ایزوترم لانگمیر و فروندلیچ و سینیتک شبه درجه دوم تبعیت مناسبی داشت. نتیجه گیری: با توجه به نتایج می توان گفت که جذب رنگ هم به صورت چند لایه ای و تک لایه ای صورت می گیرد و اصلاح اسکوریا با اسید استیک موجب افزایش کارایی آن نسبت به اسکوریا طبیعی می شود

    Data on the effect of geological and meteorological parameters on indoor radon and thoron level- case study: Kermanshah, Iran

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    The present study was aimed to evaluate the relationship between indoor radon and thoron concentrations, geological and meteorological parameters. The radon and thoron concentrations were determined in three hospitals in Kermanshah, the west part of Iran, using the RTM-1688-2 radon meter. Also, the type and porosity of the underlying soil and the meteorological parameters such as temperature, humidity, atmospheric pressure, rainfall and wind speed were studied and the obtained results analyzed using STATA-Ver.8. In this study the obtained radon concentration was furthered in buildings which constructed on the soil with clayey gravel and sand feature than the soil with clay characteristic and little pasty with a significant difference (P < 0.05). While the lower coefficient about 1.3 was obtained in measured the thoron concentration and a significant difference was not observed. So the soil porosity can extremely effect on the indoor radon amount. Among all studied meteorological parameters, temperature has been determined as the most important meteorological parameter, influence the indoor radon and thoron concentrations. Keywords: Indoor radon, Indoor thoron, Geology, Meteorological parameters, Kermanshah, Ira

    Efficient degradation of 4-chloro-2-nitrophenol using photocatalytic ozonation with nano-zinc oxide impregnated granular activated carbon (ZNO–GAC)

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    In this paper, the catalytic capability of nano-zinc oxide impregnated granular activated carbon (ZnO–GAC) in photocatalysis and ozonation hybrid system was studied. ZnO–GAC hybrid was prepared by co-precipitation method. FeSEM, XRD, FTIR, EDAX were applied to characterize the structure and morphological feature. 4-chloro-2-nitrophenol (4C2N) was employed as model pollutant to evaluate the catalytic ability of ZnO-GAC. The effect of GAC content and stability of ZnO-GAC in photocatalytic ozonation was also evaluated. The findings indicated that photocatalytic ozonation of 4C2N with ZnO-GAC hybrid was a very efficient technique for 4C2N degradation. The TOC removal efficiency found 100% by ZnO-GAC/O3/UV in 55 min, which is 1.20 times as great as that of ZnO/ O3/UV process. Moreover, the catalytic capability of ZnO–GAC hybrid remained very stable after recycling for five sequential tests. This enhancement is due to the enhanced separation efficiency of photo-generated charges, which simplified the electrons trapping by ozone and improved the yield of hydroxyl radical

    Data for factor analysis of hydro-geochemical characteristics of groundwater resources in Iranshahr

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    Detection of Hydrogeological and Hydro-geochemical changes affecting the quality of aquifer water is very important. The aim of this study was to determine the factor analysis of the hydro-geochemical characteristics of Iranshahr underground water resources during the warm and cool seasons. In this study, 248 samples (two-time repetitions) of ground water resources were provided at first by cluster-random sampling method during 2017 in the villages of Iranshahr city. After transferring the samples to the laboratory, concentrations of 13 important chemical parameters in those samples were determined according to o water and wastewater standard methods. The results of this study indicated that 45.45% and 55.55% of the correlation between parameters has had a significant decrease and increase, respectively with the transition from warm seasons to cold seasons. According to the factor analysis method, three factors of land hydro-geochemical processes, supplying resources by surface water and sewage as well as human activities have been identified as influential on the chemical composition of these resources.The highest growth rate of 0.37 was observed between phosphate and nitrate ions while the lowest trend of − 0.33 was seen between fluoride ion and calcium as well as chloride ions. Also, a significant increase in the correlation between magnesium ion and nitrate ion from warm seasons to cold seasons indicates the high seasonal impact of the relation between these two parameters. Keywords: Hydro-geochemistry, Factor analysis, Correlation matrix, Groundwater resources, Iranshah

    Data for comparison of chlorine dioxide and chlorine disinfection power in a real dairy wastewater effluent

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    Disinfection of water refers to a special operation that is doing to kill or disable causative organisms (i.e. Pathogens) and in particular, intestinal bacteria. The aim of this pilot study is comparison of disinfection power of Chlorine dioxide and chlorine in a real dairy wastewater effluent. In this regard, firstly prepared two 220-l tanks made of polyethylene as reaction tanks and filled by effluent of a dairy wastewater treatment plant. Both tanks were equipped with mechanical stirrer. Then a Diaphragm dosing pumps with the maximum capacity of 3.9 l per hour were used for the chlorine dioxide and chlorine (Calcium hypochlorite) 0.5 up to 3 ppm injection. Residual level of Chlorine dioxide and Chlorine were measured by portable photometric method DT4B kit, Germany. Finally, the Multiple-Tube Fermentation, Brilliant Green Bile Broth (BGB) and Eosin methylene blue Agar (EMB) technique was used for microbial analysis and the results were reported as the most probable number index (MPN) respectively. The data showed that the residual of chlorine dioxide could stood more active than residual of chlorine in the aqueous environment significantly. Therefore, Use of chlorine dioxide is more effective than chlorine for removal fecal and total coliform from dairy wastewater effluent. Keywords: Disinfection, Chlorine dioxide, Chlorine, Total coliform, Fecal colifor

    Data for inactivation of free-living nematode Rhabditida from water environment using ultraviolet radiation

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    Sometimes free-living nematodes in conventional water treatment processes are not eliminated and cause adverse health effects in water consumer. So, the efficiency of UV lamps (125 W) with irradiation intensity 1020 μW cm−2 on inactivation of free-living nematode Rhabditida released in water samples has been investigated along with the investigation of the effects of turbidity and change of temperature and exposure time in constant of pH 8 ± 0.2. The results showed that UV radiation could disabled the larval and adult nematodes after 12 and 15 min in the presence of turbidity 5 NTU, respectively. Also, increased turbidity up to 50 NTU decreased the inactivation efficiency of larval and adult nematodes from 100% to 73% and 64%, respectively. In addition, with increased temperature, the inactivation efficiency increased significantly in a short time. The results showed a significant relationship between increasing exposure time and temperature and turbidity reduction with UV radiation efficiency in the inactivation of the nematode (P < 0.00). It was also found that the efficiency of the lamp on nematode larvae was more than the adult nematode. Therefore, UV radiation can well inactivate larvae and then adult free-living nematode Rhabditida in water. Keywords: Ultraviolet, Water treatment, Nematode, Rhabditida, Disinfectio

    Dataset for effect comparison of irrigation by wastewater and ground water on amount of heavy metals in soil and vegetables: Accumulation, transfer factor and health risk assessment

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    The irrigation source plays an important role in the amount of contaminates in soil and cultivated agricultural products. In this study, the concentration and human health risks of heavy metals (Zn, Mn, Cu, Cr, Cd and Pb) were evaluated in soil, water and vegetables collected from two sites (FGW: Farms irrigated with ground water, FWW: Farms irrigated with wastewater) of Bushehr, Iran. The trend of heavy metals concentration in vegetables from either site was in the following order: Mn ˃ Zn ˃ Cu ˃ Pb ˃ Cr ˃ Cd. Except Cd and Pb, the concentration of heavy metals was in the range of European Union (2006) permissible limit. THQ (Target hazard quotient) values were the highest in Mn followed by the Pb, Cd, Cu, Zn and Cr. Mn, Pb and Cd exceeded safe limit of THQ in several cases, while THQ of other heavy metals was in the range of safe limit. Based on the results, it can be concluded that heavy metals contamination in vegetables grown in Bushehr, especially in FWW site, may pose a great health risks to the local inhabitant through consumption of vegetables. Therefore, it is recommended that the discharge of industrial and municipal wastewater into water resources witch used for vegetable irrigation should be the first step in controlling the level of heavy metals in vegetables. Keywords: Heavy metals, Vegetables, Health risk, Busheh

    Speciation of As(ΙΙΙ)/As(V) and Total Inorganic Arsenic in Biological Fluids Using New Mode of Liquid-Phase Microextraction and Electrothermal Atomic Absorption Spectrometry.

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    In this paper, a new extraction method based on countercurrent liquid–liquid microextraction (CLLME) has been developed for the extraction and preconcentration of inorganic arsenic (iAs) in plasma and urine samples prior to their analysis by electrothermal atomic absorption spectrometry (ETAAS). In this method, firstly, 5 ml of water is added to the extraction vessel. Then 30.0 μl of the extracting solvent is added to it in order for the extracting solvent to be placed in the narrow-necked vessel. In total, 10 ml of a standard solution or a pretreated real sample is added to the sample container and it is connected to the extraction vessel via a connector. While opening the embedded valve at the bottom of the sample container and the one in the extraction vessel, the sample solution flows into the extracting solvent with the same flow rate, leading to the successful extraction of metal ligand into the extracting organic solvent. Under the optimum conditions, calibration curves are linear in the range of 0.1–50 μg l−1, and limit of detections (LODs) are in the range of 0.03–0.05 μg l−1. The enhancement factor and enrichment factor were in the range of 220–240 and 198–212, respectively. Repeatability (intra-day) and reproducibility (inter-day) of method based on seven replicate measurements of 5.0 μg l−1 of arsenic were in the range of 2.3–3.5% and 4.0–5.7%, respectively. The applicability of the proposed CLLME and ETAAS methods was demonstrated by analyzing the iAs in spiked urine and plasma samples. The obtained recoveries of the arsenic in the range of 92–107% indicated the excellent capability of the developed method for speciation of arsenic from plasma and urine samples

    Data on using macro invertebrates to investigate the biological integrity of permanent streams located in a semi-arid region

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    The aquatic ecosystems are continuously endangered due to variety of hazardous chemicals containing different toxic agents which can be emitted from anthropogenic sources. Besides the increasing of human population, various kinds of contaminants enter into the surface water resources. The aim of the present study was to investigate the abundance and diversity of macro invertebrates in two permanent streams located in the northern part of Tehran. The biological integrity of the streams was determined by manual sampling approach at five points. The distances between the sampling points were at least 2 km. The bio indicator organisms, organic pollution, and dissolved oxygen were measured. The different types of benthic invertebrates such as riffle beetle, midge and caddish fly larvae, dragon fly, may fly and stone fly nymph, riffle beetle adult, pyralid caterpillar, leech, and pouch snail were identified. It can be concluded that, the identified benthic macro invertebrates can be served as appropriate biological indicator in the studied area. Keywords: Biological integrity, Tehran, Macro invertebrate

    Kinetic and modeling data on phenol removal by Iron-modified Scoria Powder (FSP) from aqueous solutions

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    Phenol present in industrial effluents is a toxicant matter which causes pollution of environments aqueous. In this work, scoria was modified by iron in order to increasing of adsorbent efficiency and effective removing of phenol. Effects of independent variables including pH, adsorbents dosage, contact time and adsorbate concentration on removing of phenol were studied by response surface methodology (RSM) based on the central composite designs (CCD). The characterization of raw scoria powder (RSP) and Iron-modified Scoria Powder (FSP) was determined via Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and Energy-dispersive X-ray spectroscopy (EDS). The obtained data showed modification by iron caused the growth of new crystalline of iron oxide on the surface of FSP. Evaluated data by RSM indicated the all variables especially pH are effective in removing of phenol (P-value < 0.001) and optimum condition was obtained at pH = 5, phenol concentration = 50 mg/l, adsorbent dosage = 1 g/l and contact time = 100 min to the value of 94.99% with desirability of 0.939. Results revealed that data were fitted by Langmuir isotherm (R2 = 0.9938) and pseudo second order kinetic (R2 = 0.9976). It was found that iron causes increasing the site active of scoria and let to significant removal of phenol. Keywords: Phenol, Iron-Modified scoria, RSM, Aqueous environmen
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