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Title: Skeletal fluorosis in relation to drinking water in rural areas of West Azerbaijan, Iran Author(s): Mohammadi, AA; Yousefi, M; Yaseri, M; Jalilzadeh, M; Mahvi, AH Abstract: Skeletal fluorosis resulting from high fluoride level in drinking water is a major public health problem. The present study evaluated the association between exposures to drinking water fluoride and skeletal fluorosis in 5 villages of Poldasht County, Iran. All the data and information on the prevalence of bone diseases were obtained from the Health Record Department, Poldasht Health Centre. To obtain the odds ratio of bone disease problem in different risk factors, when considering the cluster effect of rural area, logistic regression in a multilevel model was used. Results showed that skeletal fluorosis of people who live in areas with high fluoride concentration is 18.1% higher than that of individuals who live in areas with low fluoride concentration. Skeletal fluorosis (54.5%) was observed in the age group of 71 years and above, and was more commonly found in females than males. According to Unadjusted, individuals who consume <= 3 unit milk and dairy products per week have almost the same level of bone diseases as compared to those that consume more than 3 units. This study indicated that, skeletal fluorosis is a general health problem in these rural areas because the results revealed that high percentage of the studied population had symptoms of skeletal fluorosis. |
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Title: Data on water quality index for the groundwater in rural area Neyshabur County, Razavi province, Iran Author(s): Yousefi, M; Saleh, HN; Mohammadi, AA; Mahvi, AH; Ghadrpoori, M; Suleimani, H Abstract: Public health is at risk from physical and chemical contaminants in the drinking water which may have immediate health consequences. The data from the current study was evaluated for groundwater quality in the rural villages of Neyshabur County in Iran. For determination of the essential physicochemical parameters, water samples were collected from 30 randomly-selected water wells during 2013 and 2014. The samples were tested in situ to measure physical parameters of pH and electrical conductivity and chemical parameters of total dissolved solids, total hardness and levels of calcium, magnesium, carbonates, bicarbonates, sodium, potassium, chloride and sulfates. The APHA method was applied to determine the physicochemical parameters of the water samples. |
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Title: Dataset on the spent filter backwash water treatment by sedimentation, coagulation and ultra filtration Author(s): Mahdavi, M; Ebrahimi, A; Azarpira, H; Tashauoei, HR; Mahvi, AH Abstract: 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 (PAFCI) and ferric chloride (FeCl3) were investigated with respect to their performance on treated SFBW quality. Samples were collected from Isfahans 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 PAFCI used as coagulant). |
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Title: Dataset on the cost estimation for spent filter backwash water (SFBW) treatment Author(s): Ebrahimi, A; Mahdavi, M; Pirsaheb, M; Alimohammadi, F; Mahvi, AH Abstract: The dataset presented in this article are related to the research article entitled "Hybrid coagulation-UF processes for spent filter backwash water treatment: a comparison studies for PAFCI and FeCl3 as a pre-treatment" (Ebrahimi et al., 2017) [1]. This article reports the cost estimation for treating produced spent filter backwash water (SFBW) during water treatment in Isfahan-Iran by various methods including primary sedimentation, coagulation & flocculation, second clarification, ultra filtration (UF) and recirculation of settled SFBW to water treatment plant (WTP) entrance. Coagulation conducted by PAFCI and FeCl3 as pre polymerized and traditional coagulants. Cost estimation showed that contrary to expectations, the recirculation of settled SFBW to WTP entrance is more expensive than other method and it costs about $ 37,814,817.6. Versus the cheapest option related to separate primary sedimentation, coagulation & flocculation in WTP. This option cost about $ 4,757,200 and $ 950,213 when FeCl3 and PAFCl used as coagulant, respectively. (C) 2017 The Authors. Published by Elsevier Inc. |
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Title: Contamination and ecological risk assessment of heavy metals in street dust of Tehran, Iran Author(s): Kamani, H; Mahvi, AH; Seyedsalehi, M; Jaafari, J; Hoseini, M; Safari, GH; Dalvand, A; Aslani, H; Mirzaei, N; Ashrafi, SD Abstract: Heavy metals are introduced in human tissue through breathing air, food chain and human skin. They can cause damage to the nervous system and internal organs. In the present study, sixty street dust samples were collected from the central area of Tehran and were digested in the laboratory to determine the content of Zn, Ni, Cd, Cr, Cu and Pb, using inductively coupled plasma optical emission spectrometry (ICP-OES). The level of contamination with the analyzed metals was determined according to the following indices: geo-accumulation index (I (geo)), enrichment factor (EF), pollution index (PI), integrated pollution index (IPI) and potential ecological risk index (RI). The average concentration of heavy metals found was in the order of Zn > Cu > Pb > Ni > Cr > Cd. The average I (geo) values for Cd, Cr, Cu, Ni, Pb and Zn were 1.53, -1.88, 2.68, -0.67, 1.62 and 2.70, respectively. Among the investigated heavy metals, zinc and copper had the maximum average EF values and were placed into the "very severe enrichment" class. Potential ecological risk factor (E (r)) also indicated that Cd had the highest risk, and it was classified as of considerable potential ecological risk. Therefore, it is necessary to pay more attention to the appearance of Cd in the human environment. The calculated potential ecological risk index values also illustrated that the street dust samples presented a "moderate ecological risk." The calculated IPI values showed that the pollution levels of the street dust samples ranged from high to extremely high. |
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Title: Application of novel Modified Biological Aerated Filter (MBAF) as a promising post-treatment for water reuse: Modification in configuration and backwashing process Author(s): Nikoonahad, A; Ghaneian, MT; Mahvi, AH; Ehrampoush, MH; Ebrahimi, AA; Lotfi, MH; Salamehnejad, S Abstract: Biological Aerated Filter (BAF) reactors due to their plentiful biomass, high shockability, high efficiency, good filtration, availability and lack of need for large land areas, are enjoying from great importance in advanced wastewater treatment. Therefore, in this study, Polystyrene Coated by Sand (PCS) was produced as a novel media and its application in a modified down-flow BAF structure for advanced wastewater treatment was assessed in two steps. In step one, the backwash effluent did not return to the system, while in step two backwash effluent returned to increase the water reuse efficiency. The backwash process was also studied through three methods of Top Backwashing (TB), Bottom Backwashing (BB), as well as Top and Bottom Backwashing Simultaneously (TBBS). The results showed that return of backwash effluent had no significant effect on the BAF effluent quality. In the second step similar to the first one with slight differences, the residual average concentrations of TSS, BOD5, and COD at the effluent were about 2.5, 8.2, and 25.5 mg/L, respectively. Additionally, in step two, the mean volume of disposal sludge/volume of treated water (v(ds)/v(tw)) decreased a large extent to about 0.088%. In other words, the water reuse has increased to more than 99.91%. The backwash time in methods of TB and BB were 65 and 35 min, respectively; however, it decreased in TBBS methods to 25 min. The concentrations of most effluent parameters in this system are in concordance with the 2012 EPA Agriculture Standards, even for irrigation of Non-processed agricultural crops and livestock water consumption. (C) 2017 Elsevier Ltd. All rights reserved. |
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Title: Cancer and Non-Cancer Risk of Arsenic in Drinking Water: A Case Study Author(s): Ghafuri, Y; Kamani, H; Bazrafshan, E; Atafar, Z; Khazaie, M; Mahvi, AH Abstract: Arsenic is a toxic element, which is found naturally in water sources. Due to its high toxicity it has become a serious problem in drinking water sources and also affects the health of communities. Therefore, in the present study, risk estimation and the probability of adverse health effects of exposure to arsenic from drinking water was evaluated in the rural areas of Qom province. Water samples were taken from 44 rural areas with regard to the number of rural areas and also the type of water distribution systems. The intensity, duration and frequency of exposure to arsenic in drinking water were determined. Then the hazard quotient and cancer risks ware calculated. Results showed that more than 16% of the rural population was exposed to arsenic with level above 10 mu g/L in the rural regions of Kahak County (10 +/- 6.29 mu g/L). Results of risk assessment showed that hazard quotient (HQ) were 1.7 and 2, while the cancer risk (CR) were 76 x 10(-5) and 42 x 10(-4) for 2 groups of age 1 and 2, respectively. The results indicated that the hazard quotient is higher than 1 (HQ > 1) for group 1 and group 2. For carcinogenic effects, the study indicated that the population in the Kahak region are exposed to arsenic in drinking water with the concentration of > 10 mu g/L and they are at a very high risk for cancer, due to the fact that the cancer risk for the 2 groups are more than 7.6 and 42 times the environmental protection agency (EPA) criteria, respectively. Therefore it is recommended that at first, the source and water supply system in Kahak region is to be substituted with safe drinking water and to provide health facilities and screening tests for exposed populations. |
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Title: Estimating national dioxins and furans emissions, major sources, intake doses, and temporal trends in Iran from 1990-2010 Author(s): Momeniha, F; Faridi, S; Amini, H; Shamsipour, M; Naddafi, K; Yunesian, M; Niazi, S; Gohari, K; Farzadfar, F; Nabizadeh, R Abstract: Background: Polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDFs) are highly toxic persistent organic pollutants (POPs), which can cause various health outcomes, such as cancer. As a part of the National and Sub-national Burden of Disease Study (NASBOD), we aimed to estimate dioxins and furans national emissions, identify their main sources, estimate daily intake doses, and assess their trend from 1990-2010 in Iran. |
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Title: A new recycling technique for the waste tires reuse Author(s): Derakhshan, Z; Ghaneian, MT; Mahvi, AH; Conti, GO; Faramarzian, M; Dehghani, M; Ferrante, M Abstract: In this series of laboratory experiments, the feasibility of using fixed bed biofilm carriers (FBBC) manufactured from existing reclaimed waste tires (RWTs) for wastewater treatment was evaluated. To assess polyamide yarn waste tires as a media, the fixed bed sequence batch reactor (FBSBR) was evaluated under different organic loading rate (OLRs). An experimental model was used to study the kinetics of substrate consumption in biofilm. Removal efficiency of soluble chemical oxygen demand (SCOD) ranged by 76-98% for the FBSBR compared to 71-96% in a sequencing batch reactor (SBR). Removal efficiency of FBBC was significantly increased by inoculating these RWTs carriers. The results revealed that the sludge production yield (Yobs) was significantly less in the FBSBR compared to the SBR (p < 0.01). It also produced less sludge and recorded a lower stabilization ratio (VSS/TSS). The findings show that the Stover-Kincannon model was the best fit (R-2 > 99%) in a FBSBR. Results from this study suggest that RWTs to support biological activity for a variety of wastewater treatment applications as a biofilm carrier have high potential that better performance as COD and TSS removal and sludge settling properties and effluent quality supported these findings. |
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Title: Remediation of total petroleum hydrocarbons using combined in-vessel composting and oxidation by activated persulfate Author(s): Asgari, AR; Nabizadeh, R; Mahvi, AH; Nasseri, S; Dehghani, MH; Nazmara, S; Yaghmaeian, K Abstract: This study was investigated the efficiency of activated persulfate and in-vessel composting for removal of total petroleum hydrocarbons. Remediation by activated persulfate with ferrous sulfate as pre-treatment was done at batch system. In the chemical oxidation, various variables including persulfate concentrations (10-3000 mg/g as waste), pH (3-7), ferrous sulfate (0.5-4 mg/g as waste) and temperature (20-60 degrees C) were studied. In the biological system, premature compost was added as an amendment. The filter cake to compost ratio were 1: 0 (as control) and 1: 5 to 15 (as dry basis). C:N:P ratio and moisture content were 100:5:1 and 45-60%, respectively. The results showed that acidic pH (pH=3) had high efficiency for the removal of total petroleum hydrocarbons by activated persulfate. Temperature had the significant effect during the persulfate oxidation. When ferrous sulfate was used as an activator for degradation at acidic condition and 60 degrees C, removal efficiency increased to 47.32%. The results of biological process showed that the minimum total petroleum hydrocarbons removal in all reactors was 62 percent. The maximum and minimum removal efficiency was obtained at 1:5 (69.46%) and 1:10 (62.42%) mixing ratios, respectively. Kinetic study showed that second order kinetic model (R-2>0.81) shows the best agreement with the experimental data and the rate of TPH degradation at low mixing ratio (1:3) was faster than high mixing ratio (1:15). Therefore, according to the results, in-vessel composting after pre-treatment by activated persulfate is suggested as an efficient process for degradation of total petroleum hydrocarbons. |
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Title: Adsorption of nitrate onto anionic bio-graphene nanosheet from aqueous solutions: Isotherm and kinetic study Author(s): Ghadiri, SK; Nasseri, S; Nabizadeh, R; Khoobi, M Nazmara, S; Mahvi, AH Abstract: In this article, bio-graphene nanosheet was prepared using an agricultural waste and converted to a weak base anionic exchanger. Anionic bio-graphene nanosheet structural characteristics and exchanger capacity for nitrate removal from aqueous solution and optimizations of various experimental parameters were evaluated. Nitrate adsorption was done with developing prediction model using the response surface methodology. In addition, regeneration rate was evaluated with eluting HCl (0.1 mol/L) solution. The results of the removal model disclosed that initial concentration of nitrate had reverse effects on the nitrate removal and the effects of other variables (adsorbent dose, contact time and pH) at the pH of zero-point charge was direct. The adsorption data obtained from experiments were in line with the pseudo-second-order kinetic (R-2 = 0.998) and Langmuir isotherm (R-2 = 0.943). Based on the Langmuir model, the maximum adsorption capacity (Q(max)) for nitrate removal by anionic bio-graphene nanosheet was 182.506 mg/g at 150 mgNO(3)(-)/L. The results of thermodynamic study showed that the enthalpychange(Delta H degrees) and entropy change (Delta S degrees) were 867.97 (kJ/mol) and 3.1432 (J/mol.K), respectively. Also, according to the results, the main mechanism of nitrate adsorption onto the anionic bio-graphene was ion exchange. In addition, regeneration process with 4 repetitions of consecutive adsorptions-regeneration cycles showed high desorption efficiencies and slight losses in its initial adsorption capacity. |
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Title: Degradation kinetics of tetracycline in aqueous solutions using peroxydisulfate activated by ultrasound irradiation: Effect of radical scavenger and water matrix Author(s): Nasseri, S; Mahvi, AH; Seyedsalehi, M; Yaghmaeian, K; Nabizadeh, R; Alimohammadi, M; Safari, GH Abstract: Degradation kinetics of the tetracycline antibiotic in aqueous solution was investigated using sulfate radicals under ultrasound irradiation. The effect of various operational parameters including initial tetracycline concentration, initial peroxydisulfate concentration, solution pH, reaction time, temperature, ultrasound power, the presence of natural organic matter, radical scavenger (tert-butyl alcohol and methanol), as well as the chemical composition of water using ultrapure water, drinking water, and secondary effluent on the degradation efficiency of tetracycline were studied. The preliminary studies were performed using only peroxydisulfate, ultrasound and ultrasound activated peroxydisulfate. The results indicated that tetracycline degradation rate increased with the increase of initial peroxydisulfate concentration, temperature and ultrasonic power, but decreased with the increase of initial tetracycline concentration. The tetracycline degradation rate was highly dependent of initial pH of the solution. The degradation of tetracycline followed the first-order kinetics. The addition of humic acid in concentrations above 10 mg.L-1 decreased the degradation rate of tetracycline, although the effect could be compensated using higher concentrations of peroxydisulfate. The role of active radicals (sulfate and hydroxyl radicals) was investigated using radical scavengers of methanol and tert-butyl alcohol. Under optimum operational conditions, 96.5% of tetracycline removal was achieved with chemical oxygen demand and total organic carbon removal of about 74% and 61.2%, respectively. The degradation rate of tetracycline was higher in drinking water compared to ultrapure water. Finally, the intermediates were identified and the possible degradation pathway of tetracycline was investigated. Overall, ultrasound activated peroxydisulfate was found to be a promising process for tetracycline degradation in aqueous solutions. |
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Title: Evaluation of groundwater quality and assessment of scaling potential and corrosiveness of water supply networks, Iran Author(s): Mirzabeygi, M; Yousefi, N; Abbasnia, A; Youzi, H; Alikhani, M; Mahvi, AH Abstract: The aim of this study was to determine the corrosion and scaling potential of water supply sources in a province in eastern Iran. In this cross-sectional study, 879 samples were taken to evaluate the water quality characteristics during 12 months (2013-2014). Five indices, Langelier, Ryznar, Puckorius, Larson-Skold, and Aggressiveness, were programmed in Microsoft Excel. The results illustrated that the values of the Langelier saturation index, Ryznar stability index, Puckorius scaling index, Larson ratio, and Aggressiveness index were 0.33 (+/- 0.17), 7.36 (+/- 0.37), 7.4 (+/- 0.6), 2.1 (+/- 1.4), and 12.03 (+/- 0.18), respectively. According to the Ryznar index (RSI), the index for the water resources of Torbat city was 6.99 and RSI for the central part of Gonabad was 6.4 (consolidation grade). The average pH in the studied water wells was 8.03. The amounts of turbidity, calcium, magnesium, nitrate, and fluoride in the study areas have favorable and acceptable conditions. However, the values of sulfate, total dissolved solids, and chloride in a few cities were higher than the standards. Comparison of five stability indices demonstrated that water in some parts of the study area is corrosive. Based on the results, selecting the best method to prevent the corrosion process is required. |
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Title: Application of Genetically Engineered Dioxygenase Producing Pseudomonas putida on Decomposition of Oil from Spiked Soil Author(s):Mardani, G; Mahvi, AH; Hashemzadeh-Chaleshtori, M; Naseri, S; Dehghani, MH; Ghasemi-Dehkordi, P Abstract: Background: It is well known that bioremediation or using microorganism enzymes plays an important role in decomposition and changing of oil pollutants and PAH compounds into nonhazardous or less-hazardous substances. The genetically manipulated bacteria like Pseudomonas sp. can enhancement the natural biodegradation activity of polycyclic aromatic hydrocarbons (PAHs) in polluted cities. Pseudomonas putida (P. putida) is a saprotrophic soil bacterium that is found throughout various environments such as soil and freshwater environments. Oil and petroleum industries are important exposure of PAHs in environment that strongly associated with the development of human cancers. |
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Title: A Review of Adverse Effects and Benefits of Nitrate and Nitrite in Drinking Water and Food on Human Health Author(s): Parvizishad, M; Dalvand, A; Mahvi, AH; Goodarzi, F Abstract: Introduction: The problem related to water pollution of nitrates and nitrites is both an issue in Iran and also most parts of the world. Studies to evaluate the acute and chronic effects of nitrate and nitrite have demonstrated that different concentrations of these compounds in water and food have been causing multiple diseases. |
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Title: Evaluation of formaldehyde concentration in the ambient air of a most populated Iranian city, Tehran Author(s): Dehghani, MH; Salari, M; Naddafi, K; Nazmara, S; Ahmadi, E; Kumar, P Abstract: Exposure to high levels of formaldehyde is known as both acute and chronic health problems, but the studies analyzing ambient concentrations of formaldehyde, especially in Middle East cities such as Tehran, are still rare. The aim of this study is to survey the variations in the concentration of formaldehyde in several areas with a high traffic volume of Tehran city during different seasons. The other objectives include understanding the influence of carbon monoxide, ozone and nitrogen dioxide concentrations, ambient temperature, relative humidity, and air pressure on the variation of formaldehyde concentration. Measurements were carried out during the period of 6 months between 2013 (December 22 to February 14) and 2014 (April 27 to June 20 at five different locations within the city, together with a background site. One hundred and eight samples, each averaged over 3 h from 11 a.m. to 2 p.m., were taken from the sampling locations. The average concentration of formaldehyde in the spring (22.7 +/- 5.3 ppb) was found about 1.31 times higher than winter (17.3 +/- 4.2 ppb). Formaldehyde concentrations demonstrated a significant correlation with the changes in air temperature (in the range of 0.46 to 0.66 for different locations) but not having any strong correlation with humidity and pressure. Carbon monoxide and nitrogen dioxide showed a significant coefficient of determination with formaldehyde concentrations with R-2 as 0.80 and 0.67 during the winter, respectively, whereas the corresponding R-2 values during spring were 0.39 and 0.41. Ozone showed a significant correlation with formaldehyde (R-2 = 0.64) during the spring and has not such the significant correlation during the season winter (R-2 = 0.23). Overall, it concluded that road vehicles were recognized as main contributor of formaldehyde production during both the seasons, especially in the winter, also, photochemical oxidation was another important and considerable contributor producing formaldehyde during the spring. |
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Title: Fluoride concentration level in rural area in Poldasht city and daily fluoride intake based on drinking water consumption with temperature Author(s): Mohammadi, AA; Yousefi, M; Mahvi, AH Abstract: Long-term exposure to high level of fluoride can caused several adverse effects on human health including dental and skeletal fluorosis. We investigated all the drinking water source located in rural areas of Poldasht city, west Azerbaijan Province, North West Iran between 2014 and 2015. Fluoride concentration of water samples was measured by SPADNS method. We found that in the villages of Poldasht the average of fluoride concentration in drinking water sources (well, and the river) was in the range mg/l 0.28-10.23. The average daily received per 2 I of drinking water is in the range mg/l 0.7-16.6 per day per person. Drinking water demands cause fluorosis in the villages around the area residents and based on the findings of this study writers are announced suggestions below in order to take care of the health of area residents. |
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Title: Adsorption of Cr(VI) ions from aqueous systems using thermally sodium organo-bentonite biopolymer composite (TSOBC): response surface methodology, isotherm, kinetic and thermodynamic studies Author(s): Dehghani, MH; Zarei, A; Mesdaghinia, A; Nabizadeh, R ; Alimohammadi, M; Afsharnia, M Abstract: Chromium, as a serious environmental contaminant, is frequently encountered in different industrial effluents. In the present study, we focused on the combined application of a surfactant-modified bentonite and chitosan for the removal of Cr(VI). In addition, the effects of several important parameters such as pH (2-8), adsorbent dosage (0.1-1.5 g/L), Cr(VI) concentration (20-200 mg/L) and contact time (60-240 min) were also investigated and the process was optimized by means of response surface methodology. The analysis of variance of the quadratic model demonstrates that the model was highly significant. Optimized values of pH, adsorbent dosage, initial Cr(VI) concentration and contact time were found to be 3.7, 1.40 g/L, 77 mg/L and 180 min, respectively. The results revealed that the prepared adsorbent had significant adsorption capacity (124.1 mg/g) for Cr(VI). All results showed that thermally sodium organo-bentonite biopolymer composite (TSOBC) had a good affinity toward Cr(VI). Among the isotherm models tested, Langmuir isotherm model was found to be the best fit for the obtained data. The adsorption kinetics indicated that Cr(VI) adsorption on TSOBC followed pseudo-second-order better than pseudo-first-order model. Moreover, thermodynamic studies showed that adsorption of Cr(VI) on TSOBC was spontaneous and endothermic in nature. The applied adsorbent was characterized by scanning electron microscopy, X-ray diffraction, energy dispersive X-ray and Fourier-transform infrared spectroscopic techniques. |
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Title: Modified natural zeolite using ammonium quaternary based material for Acid red 18 removal from aqueous solution Author(s): Mirzaei, N; Ghaffari, HR; Sharafi, K; Velayati, A; Hoseindoost, G; Rezaei, S; Mahvi, AH ; Azari, A; Dindarloo, K Abstract: The aims of this study were to modify local clinoptilolite zeolite (CZ) to surfactant modified form and investigate its potential for acid red 18 (AR18) removal from aqueous solution. Hexadecyltrimethylammonium chloride (HDTMA-CL) was applied to promote the adsorption capacity of CZ. X-ray diffraction (XRD), X-ray fluorescence (XRF), and scanning electron microscopy (SEM) were utilized to determine physical, chemical, and morphological properties of raw and modified CZ. Batch experiments were carried out to investigate the isotherms and kinetic models of AR18 adsorption on surfactant modified clinoptilolite zeolite (SMCZ). Besides, the effect of contact time and initial dye concentration on removal efficiency were examined. Nonlinear isotherms and kinetic models was obtained using Goodness of fit (GooF) method. Also, removal mechanism was discussed. Higher removal efficiencies were observed as the detention time was increased and the process reached to the equilibrium during 150 min. GooF results showed that the best isotherm for a description of adsorption equilibrium data was Langmuir model. The maximum adsorption capacity of 11 mg/g was obtained according to Langmuir equation. Also, kinetic studies showed that adsorption followed an Elovich model. The initial sorption rate of 5.8 mg/g min was obtained for selected kinetic. Electrostatic adsorption was determined as possible removal mechanism. The SMCZ can be used as an efficient adsorbent for AR18 removal from aqueous solution because of its low cost, and high availability in nature. |
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Title: Decolorization of Direct Blue 71 solutions using tannic acid/polysulfone thin film nanofiltration composite membrane; preparation, optimization and characterization of anti-fouling Author(s): Yousefi, N; Nabizadeh, R; Nasseri, S; Khoobi, M; Nazmara, S; Mahvi, AH Abstract: The objective of this research was to use tannic acid (TA) as polyphenol monomer and trimesoyl chloride (TMC) to synthesize the nano-composite membranes and its application for dye removal from water. The combined effects of factors were studied by response surface methodology (RSM). Synthesized membrane was characterized by field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) and water contact angle measurement. The results showed that monomer concentrations and post treatment (time and temperature) had a significant effect on the membrane synthesis. The predicted optimum operational conditions were initial direct blue 71 concentration of 30.31 mg/L; time of 16.96 min, applied pressure of 1.16 bar. Fouling mechanism was pore sealing (n=1.96). The excellent antifouling properties and resistance ability to organic and chemical reagents of the prepared composite nanofiltration membranes caused to suggest this membrane for water treatment. |
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Title: Remediation of Heavy Metals Contaminated Silty Clay Loam Soil by Column Extraction with Ethylenediaminetetraacetic Acid and Nitrilo Triacetic Acid Author(s): Naghipour, D; Jaafari, J; Ashrafi, SD; Mahvi, AH Abstract: Ethylenediaminetetraacetic acid (EDTA) as traditional chelating agent and nitrilo triacetic acid (NTA) as biodegradable chelating agent were used to evaluate the efficiency of leaching in silty-clay-loam soil contaminated with Pb, Cd, and Zn. Three concentrations of NTA and EDTA, 0.1, 0.01, and 0.005M, were used in column leaching and each was set up in triplicate. Results demonstrate that the highest efficiency of heavy metals extraction was obtained in treatments with a concentration of 0.1M EDTA and NTA. The extraction efficiency in first, second, and third pore volumes of 0.1M EDTA were 41.92, 70.35, and 81.63% of Pb, 19.26, 44.28, and 77.58% of Cd, and 41.24, 56.14, and 65.8% of Zn, respectively. Also the extraction yields in first, second, and third pore volumes of 0.1M NTA were 6.44, 14.72, and 16.78% of Pb, 47.68, 59.4, and 66.85% of Cd, an 11.44, 15.45, and 18.84 8% of Zn, respectively. Statistical analysis showed that EDTA concentration and pore volume have significant (p<0.05) effects on heavy metal leaching efficiency. At a washing solution pH of 4.5, the Pb, Cd, and Zn extraction efficiencies at the fifth pore volume were 87.25, 81.23, and 70.05% for the 0.1M EDTA and 79.7, 59.8, and 60.12% for the 0.1M NTA, respectively, when multiple heavy metals were used. The Pb, Cd, and Zn extraction efficiency for reuse of EDTA from leached solution were 99.12, 99.71, and 99.33%, respectively, for Na2S and 99.66, 99.74, and 98.59%, respectively, for Na2S/Ca(OH)2 treatment. The acidity of the environment has a significant impact on heavy metals removal for both chelating agents. The overall orders of metal extraction efficiency for EDTA and NTA that resulted from this study are Pb>Cd>Zn and Cd>Zn>Pb, respectively. |
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Title: Removing Reactive Red 120 and 196 using chitosan/zeolite composite from aqueous solutions: Kinetics, isotherms, and process optimization Author(s): Dehghani, MH; Dehghan, A; Najafpoor, A Abstract: A low-cost adsorptive composite was prepared using natural zeolite, clinoptilolite, and shrimp shell wastes as raw materials. The shrimp waste was used to synthesize chitosan by the deacetylation of chitin which was extracted from the exoskeleton of crustacean shrimps. Response surface methodology (RSM) was employed to model and optimize the effect of process variables including initial dye concentration (25-100 mg/L), solution pH (3-11), adsorbent dose (1-3 g/L), and contact time (15-180 min) on the percentage of dye removal as the response. The optimum levels of independent variables for the removal of Reactive Red 120 (RR120) were time of 138.75 min, initial concentration of 43.79 mg/L, adsorbent dose of 2 g/L, and pH of 5. The optimum values for the removal of Reactive Red 196 (RR196) were time of 125.77 min, initial concentration of 44.72 mg/L, adsorbent dose of 2.5 g/L, and pH of 5. Under optimal conditions, the predicted removal percent of the model was 91.2 and 100% for RR120 and RR196, respectively. The results showed that the experimental data of RR120 were better described by Hill and Sips isotherms, and experimental data of RR196 followed Jovanovic isotherm model. The pseudo-first order and pseudo-second-order models were employed to analyze the kinetic data. The kinetic data were well described by pseudo-second-order model with R-Adj(2) values of higher than 0.98 and 0.99 for RR120 and RR196, respectively. The results showed that all of the independent variables exhibited a significant effect on dye removal. (C) 2017 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved. |
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Title: An investigation of desalination by nanofiltration, reverse osmosis and integrated (hybrid NF/RO) membranes employed in brackish water treatment Author(s): Talaeipour, M; Nouri, J ; Hassani, AH; Mahvi, AH Abstract: Background: As an appropriate tool, membrane process is used for desalination of brackish water, in the production of drinking water. The present study aims to investigate desalination processes of brackish water of Qom Province in Iran. |
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Title: Evaluation of humic acid removal efficiency in aqueous solution by feather protein granules Author(s): Salmani, MH; Farzi, M; Mahvi, AH; Ehrampoush, MH; Askarishahi, M Abstract: The use of cheap adsorbent has been studied as an alternative substitution of activated carbon for the adsorption of the organic pollutant from aqueous solution. In the present study, the effect of contact time, pH, initial concentration of humic acid, and temperature was tested for investigation of the humic acid removal efficiency of the feather protein granule as a low-cost adsorbent. The equilibrium time was 120 min. It was found that the removal efficiency depended on pH and the highest removal was 68.3 % at pH of 3.0. The equilibrium adsorption data fitted with linear of Freundlich and Langmuir isotherm models. The thermodynamic studies revealed the endothermic and spontaneous process in 298 degrees C. The feather protein granules were successfully used for the adsorption of humic acid from aqueous solution. |
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Title: Modeling mercury (II) removal at ultra-low levels from aqueous solution using graphene oxide functionalized with magnetic nanoparticles: optimization, kinetics, and isotherm studies Author(s): Khazaei, M; Nasseri, S; Ganjali, MR; Khoobi, M; Nabizadeh, R; Mahvi, AH; Gholibegloo, E; Nazmara, S Abstract: Magnetic graphene oxide (Fe3O4@SiO2-GO) nanocomposite was fabricated through a facile process and its application was found to be an excellent adsorbent for capturing low concentrations of mercury (II) from water. The effects of four independent factors, including nanocomposite dosage, contact time, pH, and initial mercury ion concentration on the mercury (II) removal were studied, and the process was optimized using response surface methodology (RSM). The optimum values of the variables adsorbent dosage, contact time, pH, and mercury (II) initial concentration were found to be 23 mg L-1, 21 min, 5.5, and 550 ppb, respectively. The adsorbent equilibrium capacity was 328.3 mg g(-1) after 21 min. By using goodness-of-fit measures (GoFMs), the Sips isotherm was found to provide a good fit with the adsorption data (K-S = 0.388 L mg(-1), n(S) = 0.44, q(m) = 569.3 mg g(-1), and R-2 = 0.989). The mean free energy E-ads was 11.901 kJ/mol, confirmed chemisorption mechanisms. The kinetic study determined good compliance of experimental data with the double exponential kinetic model (R-2 = 0.997). |
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Title: Toxicity evaluation of phenol by-products resulted from degradation of phenol by Fe (III)-doped TiO2/UV process Author(s): Borji, SH; Nasseri, S; Nabizadeh, R; Mahvi, AH; Zare, MR Abstract: The objective of this study was the evaluation of phenol toxicity and by-products resulted from its degradation by Fe (III)-doped TiO2/UV process. 10 mg/L of phenol solution was manipulated for degradation by Fe (III)-doped TiO2 (synthesized by sol-gel method) under UV ray. By-products detected using GC-MS. In order to toxicity assessment of phenol by-products, the effluent was used in bioassay tests performed using Daphnia magna at 24, 48, 72, and 96 h exposure and 50% lethal concentration (LC50) was determined using probit analysis in SPSS ver. 16.0 software. Results indicated that after 210 min, phenol concentration was decreased to 1.022 mg/L. Detected by-products consisted of catechol, resorcinol, hydroquinone, glycerol, glutaric acid, oxalic acid, 1,2,3-benzenetriol, phenol, acetic acid, and E-2-butenedioicacid. According to the obtained values of LC(50)s, the effluent toxicity was 6-9-fold higher than that of initial phenol solution at all of the exposure times. Results of the present study confirmed that the by-products of phenol oxidation by Fe(III)-doped TiO2/UV may introduce more toxic effects on Daphnia magna and this phenomenon should be considered in the future applications. |
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Title: Risk assessment of haloacetic acids in the water supply of Tehran, Iran Author(s): Ghoochani, M; Rastkari, N; Heibati, B; Ghozikali, MG; Jeddi, MZ; Fawell, J; Nazmara, S; Mahvi, AH Abstract: Disinfection by-products are compounds occurring in drinking water as a result of reactions between disinfectants and impurities in raw water, and their occurrence has been a public health concern for the last four decades. Haloacetic acids (HAAs) are one of the major by-products of chlorination. The concentration and variation of HAAs was monitored in 540 samples taken from tap water in six water and wastewater districts of Tehran, Iran. Seasonal variation indicated that natural organic matter and HAA levels were much higher in the spring and fall seasons. The concentrations of HAAs in drinking water samples varied with water sources. They were higher in drinking water obtained from surface water. In this study, the analysis method of human health risk assessment with regard to exposure to HAAs by drinking water in Tehran was based on the United States Environmental Protection Agency (USEPA) guideline. It was found from these studies that the risk to human health appears to be negligible. |
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Title: EPIDEMIOLOGY OF DRINKING WATER FLUORIDE AND ITS CONTRIBUTION TO FERTILITY, INFERTILITY, AND ABORTION: AN ECOLOGICAL STUDY IN WEST AZERBAIJAN PROVINCE, POLDASHT COUNTY, IRAN Author(s): Yousefi, M; Mohammadi, AA; Yaseri, M; Mahvi, AH Abstract: Research, including animal studies, shows that the fluoride ion (F) adversely impacts the reproductive system in mammals. However, the gene-environment interaction mechanisms involved in this association remain unclear. The objective of the present study was to measure the F level in two regions of Poldasht county, Iran, with low and high drinking water F levels (means 1.90 and 8.10 mg/L, respectively) and to examine, in females living in the areas, the relationship between the drinking water F and (i) fertility, (ii) infertility without known etiological factors, and (iii) abortion without known etiological factors. Comparing the women in the low and high F areas, the respective rates were: (i) fertility: 105/1993, 5.3%; 70/1224, 0.5%; (ii) infertility without known etiological factors: 17/ 1993, 0.9%; 24/1224, 2.0%; and (iii) abortion without known etiological factors: 6/105, 5.7%; 11/70, 10.0%. We found that there were no statistically significant differences in the reproductive parameters between the low and high F regions when the women were considered by 5-year age groups, but, when the data were pooled and all the age groups were considered together in a group with ages 10-49 yr, those in the low F group were more fertile (p<0.05) and had lower rates of (i) infertility without known etiological factors (p<0.001) and (ii) abortion without known etiological factors (p<0.001). |
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Title: Quality and quantity of construction and demolition waste in Tehran Author(s): Asgari, A; Ghorbanian, T; Yousefi, N; Dadashzadeh, D; Khalili, F; Bagheri, A ; Raei, M; Mahvi, AH Abstract: Background: In recent years the generation rate of construction and demolition waste (C&D) has significantly augmented. The aim of this study was to assessed the quality and quantity of construction and demolition waste in Tehran (capital of Iran). |
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Title: Risk assessment of water supply system safety based on WHO Water Safety Plan; Case study: Ardabil, Iran Author(s): Aghaei, M; Nabizade, R; Nasseri, S; Naddafi, K; Mahvi, AH; Karimzade, S Abstract: safety plan (WSP). This research was conducted to assess and identify the vulnerable points in Ardabil water supply system based on WSP in 2014. Initial investigations were performed using WSP quality assurance (QA) tool. At first, WSP checklists were prepared and filled up by experts and data analysis using WSP QA tool. Then, system hazards were listed and prioritized according to WHO matrix by team members scientific view and then risk analyses were prepared. Results showed that "System Description" and "Management Procedure" phases scored the highest and the lowest grades, respectively. Discharge of wastewater by communities in catchment area, trihalomethanes generation in finished water, old infrastructures, old pipes, and consequently pressure drop in point of use were identified as the most important hazardous events. With regard to the low level of overall implementation in WSP steps and lack of enough attention to water supply system in some phases, current control approach has no sufficient efficiency to provide safe drinking water. Collaboration and support of health authorities can lead to better performance and improvement of water safety in water supply system. |
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Title: Removal of methylene blue dye from aqueous solutions by a new chitosan/zeolite composite from shrimp waste: Kinetic and equilibrium study Author(s): Dehghani, MH; Dehghan, A; Alidadi, H; Dolatabadi, M; Mehrabpour, M; Converti, A Abstract: The adsorption of methylene blue dye (MBD) from aqueous solutions was investigated using a new composite made up of shrimp waste chitosan and zeolite as adsorbent. Response surface methodology (RSM) was used to optimize the effects of process variables, such as contact time, pH, adsorbent dose and initial MBD concentration on dye removal. The results showed that optimum conditions for removal of MBD were adsorbent dose of 2.5 g/L and pH of 9.0, and initial MBD concentration of 43.75mg/L and contact time of 138.65 min. The initial concentration of dye had the greatest influence on MBD adsorption among other variables. The experimental data were well fitted by the pseudo-second order kinetic model, while the Freundlich isotherm model indicated a good ability for describing equilibrium data. According to this isotherm model, maximum adsorption capacity of the composite was 24.5mg/g. Desorption studies showed that the desorption process is favored at low pH under acidic conditions. |
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Title: Investigating the removal of residual iron from water through coagulation by means of phosphate compounds Author(s): Dehghani, MH; Ghanbari, R Abstract: The removal of residual iron in conventional and enhanced coagulation process by use of phosphate compounds was investigated. Jar test was performed on sequences of rapid mixing, slow mixing and sedimentation. Addition of phosphate compounds was accomplished during rapid mixing. Phosphate compounds were added to the jars in concentrations of 0.5, 1, 1.5, 2, 2.5, 3 and 3.5 mg L-1. Dosage of ferric chloride in conventional coagulation test was 10 mg L-1, and the experiments took place in - different temperatures (35 degrees C, 22 degrees C and 5 degrees C) and pHs (8.5, 7.5, 6.5 and 5.5). Dosages of ferric chloride were 20, 30, 40 and 50 mg L-1 in enhanced coagulation tests, which applied in two pHs (5.5 and neutral pH of water). The results obtained showed that concentrations of residual iron in pH of 5.5, 6.5, 7.5 and 8.5 were 0.32, 0.15, 0.08 and 0.22 mg L-1, respectively. Maximum removal of iron was 0.27 mg L-1, which took place in pH 5.5. Maximum and minimum concentrations of residual phosphate were detected at pHs of 8.5 and 5.5, respectively. Concentration of iron reached its maximum (0.18 mg L-1) in coagulant dosage of 40 mg L-1. Maximum removal of iron in this stage (0.1 mg L-1) happened in coagulant dosages of 30 and 40 mg L-1. Residual iron concentrations in enhanced coagulation at pH of 5.5 were 0.31, 0.72, 0.93, 1.2 and 1.68 mg L-1, which took place in coagulant dosages of 10, 20, 30, 40 and 50 mg L-1, respectively. Maximum removal of residual iron was 0.35 mg L-1, which happened in coagulant dosages of 50 mg L-1. |
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Title: High turbid water treatment by Kenaf fibers: a practical method for individual water supply and remote areas Author(s): Mahdavi, M ; Mahvi, AH; Pourzamani, H; Fatehizadeh, A; Ebrahimi, A Abstract: Fast and easy access to simple methods for water treatment is one of the most important issues in the field of environmental health, water, and wastewater engineering. The aim of this study was to investigate the application of kenaf fibers for the fast treatment of high turbid water. To evaluate its ability, a pilot plant with various lengths (17.5, 35 and 70 cm) and weight (35 and 70 g) of fibers was used. A synthetic high turbid water (700 NTU) was prepared by mixing the kaolin and riverbed sediments. A samples were analyzed for residual turbidity, true colour, UV254 absorbance and total organic carbon (TOC). The findings showed that at the optimum condition, the removal efficiency of turbidity, true colour, and UV254 by kenaf fibers with 35 cm length was 99.93, 95.09 and 71.43%, respectively. Also, the quantity of produced water was 0.00368 L/g kenaf/h. This study showed that kenaf fibers can be used for high turbid water and fast treatment by a very simple and easy manner without any energy and chemical addition. |
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Title: A new approach in simultaneous calibration of Hazen-Williams coefficients and demand of nodes in of water distribution systems Author(s): Sherri, F; Mahvi, AH; Eshlaghy, AT; Hassani, AH Abstract: Calibration is necessary to make models of water distribution systems (WDSs) perform similarly to actual events; however, calibration is often complicated and time-consuming. The present study provides a new approach for simultaneous calibration of Hazen-Williams coefficients and nodal demand using the hydraulic simulator of the WaterGEMS that includes fast messy genetic algorithm as the optimization tool. For WDS calibration, instead of optimization using extended period approach during a day, several hourly optimization problems are considered. This reduces optimization time and computational effort. In the proposed approach, pipes and nodes are classified by physical characteristics such as age and material and topology of the water distribution network. Classification of pipes and nodes makes the decision space smaller and makes it easier to find a solution in a reasonable time. The water distribution network was calibrated at each time step separately, and then, by aggregating the results, an optimal solution was achieved to minimize the difference between the measured performance and simulation results. The validity of the proposed approach was tested for a two-loop network, and its efficiency in complicated cases was evaluated through application to a part of the Tehran WDS. The results show that the proposed method can produce acceptable results in a reasonable time even for large and complicated WDSs. The case study under actual conditions showed that the difference between observed and simulated pressure at all nodes was < 2 m and volume of computation decreased to 66.7%. |
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Title: THE EQUILIBRIUM, KINETIC, AND THERMODYNAMIC PARAMETERS OF THE ADSORPTION OF THE FLUORIDE ION ON TO SYNTHETIC NANO SODALITE ZEOLITE Author(s): Balarak, D; Mostafapour, FK; Bazrafshan, E; Mahvi, AH Abstract: The equilibrium, kinetic, and thermodynamic parameters of the adsorption of the fluoride ion (F) on to synthetic nano sodalite zeolite (SNSZ) was studied in a batch system. The SNSZ was characterized by scanning electron microscopy (SEM), X-ray fluorescence (XRF), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) techniques. The experimental data were analyzed by the Langmuir, Freundlich, Redlich-Peterson, Koble-Corrigan, and Temkin isotherm models. The equilibrium data fitted well to the Langmuir model with a maximum adsorption capacity of 25.44 mg/g at 298 K. The pseudo-second-order kinetic model best described the adsorption process. The results proved that the SNSZ was an effective adsorbent for removal of F from aqueous solution. Thermodynamic parameters including the Gibbs free energy (Delta G), enthalpy (Delta H), and entropy (Delta S) were also calculated. These parameters indicated that the adsorption of F on to SNSZ was feasible, spontaneous, and endothermic in nature. |
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Title: SYNTHESIS OF NANOCHITOSAN FOR THE REMOVAL OF FLUORIDE FROM AQUEOUS SOLUTIONS: A STUDY OF ISOTHERMS, KINETICS, AND THERMODYNAMICS Author(s): Naghizadeh, A; Shahabi, H; Derakhshani, E; Ghasemi, F; Mahvi, AH Abstract: Background: Fluorine can be a harmful element for human health. High concentrations of the fluoride ion (F) are poisonous and can damage the endocrine glands, thyroid, and liver. It can also hinder human growth, decrease intelligence, and cause digestive problems and fluorosis. Objective: The main objective of this study was to evaluate the effectiveness of nanochitosan for the removal of F from the aquatic environment. Method: The effects of various parameters such as pH, adsorbent dosage, initial concentration of F, temperature, and contact time on the removal of F were examined in a batch system. Results: The maximum adsorption capacity of the nanoparticles (9 mg F/g nanochitosan) occurred with pH=3, adsorbent dosage=0.25 g/L, and F concentration=20 mg/L. The adsorption process for the removal of F by nanochitosan was an exothermic reaction and followed the BET isotherm and the pseudo-second-order kinetic model. Conclusion: Nanochitosan has a relatively good capacity for the removal of F from aqueous solutions. |
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Title: Application of nano aluminum oxide and multi-walled carbon nanotube in fluoride removal Author(s): Rostami, I; Mahvi, AH ; Dehghani, MH; Baghani, AN; Marandi, R Abstract: The problem of environmental pollution by nanoparticles, which have recently entered the industrial processes around the world, is very important. This study aimed to determine the optimum condition (pH, initial concentration, and sorbent dosage) for removal of fluoride using multi-walled carbon nanotubes (MWCNTs) and nano aluminum oxide (Al2O3). Then, the mortality rate of Daphnia magna using Al2O3 laden with fluoride and MWCNTs laden with fluoride was investigated under the acquired optimum conditions. The obtained results showed that the highest removal rate of fluoride was 96.9% for Al2O3 at pH = 6 and 60.1% for MWCNTs at pH = 5. The lethal concentration-50 (LC50-24 h) was 0.501 g/L for MWCNTs laden with fluoride and 0.475 g/L for Al2O3 laden with fluoride. Besides, the LC50-48 h was 1.188 and 1.101 g/L for Al2O3 laden with fluoride and MWCNTs laden with fluoride, respectively. The study findings demonstrated that Al2O3 laden with fluoride and MWCNTs laden with fluoride had the lowest toxicity and mortality effects on Daphnia magna. |