Removal of toxic lead from aqueous solution using a low-cost adsorbent.

Valorization of waste materials and byproducts as adsorbents is a sustainable approach for water treatment systems. Pottery Granules (PG) without any chemical and thermal modification were used as a low-cost, abundant, and environmentally benign adsorbent against Pb(II), the toxic metal in drinking water. The porous structure and complex mineral composition of PG made it an efficient adsorbent material for Pb(II). The effect of key physicochemical factors was investigated to determine the significance of contact time, PG dose, pH, solution temperature, and coexisting ions, on the process. Pb(II) removal increased by PG dose in the range of 5-15 g/L, and agitation time from 5 to 60 min. Increasing Pb(II) concentration led to a drop in Pb(II) removal, however, adsorption capacity increased significantly as concentration elevated. Pb(II) removal also increased significantly from ~ 45% to ~ 97% by pH from 2 to 12. A ~ 20% improvement in Pb(II) adsorption after rising the solution temperature by 30˚C, indicated the endothermic nature of the process. The sorption was described to be a favorable process in which Pb(II) was adsorbed in a multilayer onto the heterogeneous PG surface. The qmax of 9.47 mg/g obtained by the Langmuir model was superior among many reported low-cost adsorbents. The Pb(II) adsorption was described well by the Pseudo- first-order kinetic model. Na+, Mg2+, Ca2+, Cd2+, and Zn2+ showed a negligible effect on Pb(II) adsorption. However, the presence of Mn2+ and Fe2+ significantly hindered the process efficacy. In conclusion, the use of waste material such as PG against Pb(II) is a viable option from the economic and effectiveness points of view.

Management and health risk assessment of chemical contamination events in water distribution systems using PSO.

An accidental or intentional contamination event can raise health and sociopolitical concerns, erode public trust, and affect the operation of water distribution systems. In this regard, emergency management plans are required to describe the necessary measures in order to deal with a threat. This study was carried out to investigate the best ways to manage intrusion in a water distribution network. In this research, the optimal management approach to deal with chemical contamination in a water distribution network was examined under three scenarios using the particle swarm optimization method. In each scenario, three management solutions were used to manage the contamination, including closing the pipe, opening the fire hydrant, and using a combination of pipe closure and fire hydrant opening. Contamination risk impact on consumers' health was assessed in the network's emergency status and after implementation of the best pollution management scenarios. The results showed that in the benchmark network, pipe closure was slightly more successful than opening of the fire hydrant valve. In pollution management of a real network, pipe closure was less effective than the hydrant opening in all scenarios. Generally, all applied scenarios were successful in reducing the contamination risk among the exposed people, so that carcinogenic and non-carcinogenic risks reduced by 100% in all scenarios compared to the non-management state.

Preparing the optimal emergency response protocols by MOPSO for a real-world water distribution network.

Water security is considered as one of the critical subjects that can arise from different issues, for instance, the injection of a poisonous pollutant into the drinking water system of a city followed by a terrorist attack. If the network lacks optimal operation to provide security against this threat, the whole population of the city can be affected by such an incident. This study aimed at preparing the optimal emergency response protocols by multi-objective particle swarm optimization (MOPSO). Furthermore, it calculates the risk of contaminants entering the network. The problem consists of three main objectives: 1) minimizing the number of operational interventions, 2) minimizing the number of polluted nodes, and 3) minimizing the number of exposed individuals. The location of closed valves and opened hydrants was chosen as decision variables. The proposed method is demonstrated using a benchmark and a real network.

Data on efficient removal of acid orange 7 by zeolitic imidazolate framework-8.

A water stable and hybrid nonporous adsorbent, cubic zeolitic imidazolate framework-8 (ZIF-8), was synthesized for Acid orange 7 (AO7) removal from aqueous solutions in batch mode. Central composite design was utilized to explore the individual and interaction effects of pH, AO7 concentration, ZIF-8 dosage and contact time on dye adsorption. A second order polynomial equation (R2 = 0.9852, LOF = 0.1419) developed for prediction of the AO7 removal. Sorption model revealed that the adsorbent dosage and the dye concentration are major factors that controlled the AO7 removal efficiency. AO7 removal increased from 55 to 80% by increasing ZIF-8 dosage from 0.2 to 1 g/L. The dye removal, on the other hand, decreased from 84 to 70% with increasing AO7 concentration from 10 to 100 mg/L and increased from 60% to 80% by decreasing pH from 12 to 4. The dye removal followed the pseudo second order kinetic and the Langmuir isotherm model. The maximum monolayer adsorption capacity of 80.47 mg dye/g of ZIF-8 was obtained according to the Langmuir model.

Calibration of water quality model for distribution networks using genetic algorithm, particle swarm optimization, and hybrid methods.

Chlorine reacts with both organic and inorganic matters in water. That is why water quality modeling has received great attention in recent years. The serious issue in municipal water quality modeling is gathering the essential input parameters of the model, particularly bulk decay (kb) and wall decay (kw) coefficients as well as their calibrations. Therefore, this study first thoroughly formulates the problem in the form of a heuristic optimization and then utilizes Genetic Algorithm, Particle Swarm Optimization, and Hybrid GA-PSO as the model optimizers in order to best calibrate kw for minimizing the difference of residual chlorine concentrations that exist between the simulated and observed values. These three algorithms are linked to EPANET, the hydraulic and water quality simulator. The method is then applied to a real-world water distribution network. Here, k w is considered as a decision variable. The objective function is to minimize both the Sum of Square Error and Root Mean Square Error between the observed and simulated chlorine concentrations. According to the simulation results obtained, the optimal value of wall decay coefficient is 1.233 m/day during the calibration process while the minimum and maximum differences between the measured and simulated chlorine rates were 0 and 0.18, respectively. •The method presented in this article can be useful for managers of water and wastewater companies, water resources facilities and operators and operation manager of water distribution system to manage chlorine dosing rate.•Due to adverse health effect of disinfection by product and poor microbial water quality as results of inefficient chlorination, control chlorine concentration in water distribution networks and its consequence on human health effect is necessary.•Hybrid PSO and GA methods are used to cope with their falling in local optimum and requiring highly computational effort.

Cadmium in Groundwater Consumed in the Rural Areas of Gonabad and Bajestan, Iran: Occurrence and Health Risk Assessment.

Evidences show that high levels of cadmium intake may be contributing to a wide range of deleterious health effects. This study was performed to estimate the concentration of cadmium and the health risk to human by cadmium through the ingestion of groundwater in 39 rural areas of Gonabad and Bajestan, eastern Iran. The mean cadmium concentrations in groundwater in the studied rural areas of Gonabad and Bajestan ranged from 0.087 to 14.32 µg/L and from 0.417 to 18.36 µg/L, respectively. Health risk quotient for cadmium contamination for 16 and 38% of children and infants in rural areas of Gonabad and Bajestan, respectively, was more than 1 which causes non-carcinogenic risk to the local population. The carcinogenic risk of cadmium in drinking water for adults, children, and infants in 16, 33, and 33% of studied rural areas of Gonabad and Bajestan, respectively, was higher than the safe limit of 1.0 × 10-4. For rural areas of Bajestan, the cancer risk in 42, 52, and 52% of adults, children, and infants was above the safe limit. It was strongly suggested that the accessible procedures of treatment should be taken for a portion of contaminated rural areas before the distribution of the groundwater for the local population.

Chemical and microbial quality of bottled drinking water in Gonabad city, Iran: Effect of time and storage conditions on microbial quality of bottled waters.

Reports from bottled water (BW) industries show a rapidly increasing rate of global bottled water consumption. The present paper contains data on chemical and microbial quality of bottled waters marketed in Gonabad city, Iran. The data on the effect of time and storing conditions on microbial quality of bottled water also is reported. The physical and chemical parameters of all 9 studied BW brands meet well with those mentioned on the labels. All BW sampled also were free of pathogenic indicators (total coliforms, fecal coliforms, fecal streptococci and clostridium perfringens). BWs kept in refrigerator have minimal heterotrophic and pathogenic bacterial count. The highest bacterial count was observed when BWs were exposed to indirect sunlight at room temperature. Presence of heterotrophic and especially pathogenic bacteria reduced significantly when the samples were placed to direct sunlight. In all samples, apart from where they were kept, the heterotrophic and pathogenic bacterial counts showed an increasing trend after bottling.

Comparison of DNA damages in blood lymphocytes of indoor swimming pool lifeguards with non-lifeguards athletes.

Chlorination has been used as a major disinfectant process for swimming pool water in many countries. The purpose of this study is to compare the DNA damage of the blood lymphocytes in indoor pool lifeguards with non-lifeguards athletes. We performed a study in which the participants were Gonabad's lifeguards. We chose 30 participants (15 male and 15 female) for each group. We collected vein blood samples from each participant in both exposed and control group. The lymphocytes were isolated from the whole blood by ficoll, and the cell viability was determined by the trypan blue. The alkaline Comet assay was also performed on lymphocytes in order to measure the DNA damage. All the parameters indicated that the DNA damage was significantly greater in lifeguards group than control group (p < 0.001). Also, the results revealed a statistically significant higher level of DNA damage in females as evident by an increase in the tail length (µm) [8.97 ± 4.21 for females as compared to 4.32 ± 1.33 for males (p = 0.001)], tail DNA (%) [4.18 ± 1.27 for females as compared to 3.14 ± 0.94 for males (p = 0.016)] and tail moment (µm) [0.68 ± 0.53 for females and 0.26 ± 0.14 for males (p = 0.010)]. There was also a significant positive correlation between DNA damage and the duration of work (P < 0.001).

Data on heavy metal concentration in common carp fish consumed in Shiraz, Iran.

Food contamination by heavy metals can lead to the accumulation of these elements in the body of consumers and the contraction of diseases. Accordingly, heavy metal concentration in common carp fishes consumed in Shiraz, Iran was determined in the present study. The mean concentrations of Pb, Cd, Zn, and Cu were 0.23, 0.07, 0.47, and 0.59 mg/kg (dry weight), respectively. The average concentration of heavy metals in the muscle of common carps consumed in Shiraz was less than the permissible standard of the WHO and FAO. The estimated weekly intake (EWI) of the studied metals was below the provisional tolerable weekly intake (PTWI). The maximum and minimum relative risk (RR) equaled 48.93 and 0.55% of the total risk for Cd and Zn, respectively.

The data of Escherichia coli strains genes in different types of wastewater.

From April 2016 to March 2017, a number of 99 isolates of Escherichia coli were collected from three types of wastewater including urban wastewater (33 isolates), livestock slaughterhouse wastewater (33 isolates) and poultry slaughterhouse wastewater (33 isolate). The specimens were cultured on microbiological media. The bacterial identification was performed by morphological and biochemical tests. Polymerase chain reaction (PCR) method was carried out to detect 2 virulence genes (traT, and fimH) and 4 antibiotic resistance genes (bla TEM, CTX, SHV , and tetA). The data showed that the prevalence rate of traT, fimH,blaCTX, blaTEM,blaSHV, tetA genes were 89.9%, 91.9%, 79.8%, 40.4%, 6.1%, and 91.9%, respectively.

Data on cadmium removal from synthetic aqueous solution using garbage ash.

This data article investigates cadmium removal efficiency using garbage ash as a cheap and effective adsorbent. Influence of different parameters, such as initial cadmium (II) concentration (mg/L), contact time (min), adsorbent dose (gr/L), pH and temperature (°C) were investigated. The characterization data of the garbage ash was determined using SEM analysis. The experimental data indicated that the adsorption of cadmium on garbage ash follows pseudo second order model and Langmuir isotherm model with R2 = 0.99. Also, the maximum adsorption capacity of adsorbent was 100.25 mg/g. Thermodynamic data showed that cadmium adsorption on garbage ash was a spontaneous and endothermic process. Based on acquired data, garbage ash could be proposed as an efficient and low-cost adsorbent for the removal of cadmium from aqueous solution.

Phenol removal from aqueous solution using Citrullus colocynthis waste ash.

Phenol is a hazardous organic chemical that introduced into the environment by industrial and pharmaceutical discharges. As a versatile option for phenol removal, adsorption would be viable if it accompanying with low cost adsorbents. This article described a natural, very cheap and local available adsorbent for phenol removal. Phenol showed a high affinity to Citrullus colocynthis waste ash which mainly composed of SiO2 (41.6%), Al2O3 (17.3%) and MgO (15.9%). Up to 70% of phenol adsorbed in the first 30 min of agitation. The phenol removal was increased by increasing adsorbent dose (0.5-10 g/L) and decreasing pH (2-12) and pollutant concentration (10-100 mg/L). The positive value of ∆H° in thermodynamic data (0.06) revealed that the process is endothermic. The high and positive value of ∆S° (13.01) and negative values of ∆G° (- 5.36 to - 7.28), showed a high affinity of phenol to the adsorbent and the spontaneous nature of the adsorption. Isotherm modelling revealed that the phenol molecules adsorbed in multilayer with the maximum adsorption capacity of 173.2 mg/g. The rate limiting step in the sorption process was chemisorption, based on the kinetic data.

Feasibility of applying the LED-UV-induced TiO2/ZnO-supported H3PMo12O40 nanoparticles in photocatalytic degradation of aniline.

In the present study, TiO2/ZnO-supported phosphomolybdic acid nanoparticles are investigated by the impregnation method, followed by analyzing their photocatalytic activity under UV-LED light and degradation kinetics degrading aniline as an organic pollutant model. Nanoparticle characteristics and the remaining Keggin structure in the nanocomposites were confirmed by means of FESEM, FTIR, and XRD analyses. Heterogenization of phosphomolybdic acid on TiO2 and ZnO nanoparticles resulted in the improved light absorption intensity and decreased band gap of nanocomposites. Photocatalytic degradation of aniline was also improved for composite nanoparticles and reached to 25.62, 43.48, and 38.25% for TiO2/HPMo, ZnO/HPMo, and TiO2/ZnO/HPMo, respectively. Overall, the results showed a good fit to the Langmuir-Hinshelwood kinetic model.

A review and investigation of the effect of nanophotocatalytic ozonation process for phenolic compound removal from real effluent of pulp and paper industry.

Phenol and its derivatives are the major environmental pollutants discharged from paper and pulp industries into water bodies. All these compounds and chlorinated phenolic compounds in particular are very toxic to fauna and flora, even at relatively low concentration. This study aimed to investigate the removal rate of phenolic compounds from the effluent of pulp and paper industries using a combination of ozonation and photocatalytic processes. Firstly, a certain volume from the effluent of paper and pulp industries containing certain phenol concentrations was obtained and fed into a prefabricated reactor at laboratory scale. Then, the combined and separate effects of zinc oxide dosage (ZnO), ozone flow rate (O3), and pH under ultra violet radiation for 30 min were evaluated. The concentration of phenolic compounds and the produced ozone gas flow rate were measured by a spectrophotometry and iodometric method, respectively. The results showed that the phenolic removal rate increased at acidic PHs compared with alkaline PHs; it was also decreased with the increase in ZnO dosages. Furthermore, the highest phenolic compound's removal rate was 99% at the optimal condition (pH 5, ZnO dosage of 0.1 g L-1 at the 30 min with UV-C illumination of 125 W). Finally, Daphnia toxicity test showed that treated effluent was safe and met the standards to the extent that it can be discharged into the receiving waters. Graphical abstract ᅟ.

Phenol Removal from Aqueous Environment by Adsorption onto Pomegranate Peel Carbon.

INTRODUCTION: Phenol and its derivatives are the most common poisonous compounds which are stable in aqueous media and lead to many health issues. In this study, application of the carbon resulted from pomegranate peel is investigated in removal of phenol by adsorption method. METHODS: to perform this cross-sectional study, first, samples of phenol with concentrations of 10 to 100 mg/L were prepared for six months in 2016. Then, the impacts of parameters such as pH, adsorbent dosage, contact time, and initial concentration of phenol in adsorption process were investigated independently in Gonabad Chemistry Lab using a spectrophotometer at 505 nm as the wavelength. Furthermore, adherence of the samples to the isotherm models of Langmuir and Freundlich was determined by Excel 2016 and descriptive statistical methods were then reported. RESULTS: The obtained results demonstrated a maximum adsorption capacity (ash) of 148.38 mgg-1 at pH 7, initial concentration of 100 mg L-1, and temperature of 23 ± 2 °C. The phenol removal rate was found to correlate directly to the adsorbent dosage and contact time, and inversely to the initial concentration of phenol. In addition, the investigations showed that the adsorption of phenol on the pomegranate peel ash follows the Freundlich model well with a correlation coefficient of R2 0.9056. CONCLUSION: Pomegranate peel ash could be used as an efficient and low-cost adsorbent for phenol removal from aqueous media.