فهرست مطالب سمیه رهدار

Dyes are one of the most important existing pollutants in textile industrial wastewater. They are often toxic, carcinogenic, teratogenic, and non-biodegredable. So the aim of this study was synthesis Fe2O3@SiO2 nanoparticle and using it as adsorbent for the removal of acid blue 92 from aqueous solutions. In this study, the electrochemical method for synthesis nanoparticle was used and characteristics of nanoparticle were analyzed by SEM (Scanning electron microscopy) technique. In this study, the effect of the pH (2-11), contact time (20-150 min), nanoparticle dosage (0.02-0.14g/L) and concentration of dye (20-120 mg/L) was investigated by one factor at the time method and then was optimized. The pH equal to 2, contact time of 40 min, and absorbent of 0.08 g/l was obtained as experimental data correlate to the pseudo-second order kinetic (R2=0.995) and Dubinin-Radushkevich adsorption isotherm model (R2=0.989). In optimal conditions, Fe2O3@SiO2 nanoparticle has well potential to quickly and effectively remove dye and simply be separated from the solution by the magnet due to its magnetic property.

Medications are of special importance in the treatment of human and veterinary diseases and the introduction of various types of antibiotics into sewage as well as wastewater has been known as the most important source of antibiotic entry into the environment. The purpose of this study was to evaluate the effectiveness of various parameters on the removal of metronidazole by the advanced oxidation process (H2O2 / MgO) from aqueous media.

This experimental study was carried out in a closed system and the effects of parameters such as pH (11, 9, 7, 5, 3), molar ratios of H2O2 / MgO (5, 3, 1.5, 1), initial concentration of metronidazole mg / L (80, 60, 40, 20), and reaction time (100, 80, 60, 40, 20 minutes) were investigated on the efficiency of metronidazole removal by advanced oxidation process.

The results of this study indicated that the advanced oxidation process (H2O2 / MgO) could remove 84.98% of metronidazole from aqueous media at an optimum pH of 3, a reaction time of 40 minutes, a metronidazole concentration of 20 mg per liter, and a molar ratio of H2O2 / MgO equivalent to 3, while the removal of metronidazole followed first-order kinetics (R2 = 0.958).

The results have shown that the use of advanced refining processes in combination (magnesium oxide nanoparticles in the presence of hydrogen peroxide) can be effective in the removal of metronidazole from aqueous solutions, and the efficiency of removal by this method is inversely correlated with pH and metronidazole concentration, while it shows a direct relationship with exposure time and molar ratio.

Introduction and Aniline is a simple aromatic compound that has a wide application in various industries. This compound has mutagenic and carcinogenic properties. Given the solubility and high toxicity of aniline, the entrance of this compound into the surface and ground water can endanger human and environment and disturb aqueous species life . Regarding this, the present study was conducted to investigate the elimination of aniline from aqueous solutions by means of Arachis hypogaea ash.
The equilibrium adsorption level was determined as a function of the solution pH (i.e., 3, 5, 7, 9, and 11), contact time (i.e., 20-150 min), adsorbent doses (i.e., 0.4, 0.6, 0.8, 1, 1.2, and 1.5 g/L), and aniline initial concentration (i.e., 20-150 mg/L). Adsorption kinetic was assessed using pseudo first order, pseudo second order, and Elovich kinetics.
According to the results, Arachis hypogaea ash was capable of reducing aniline by 65% at the pH of 7, initial aniline concentration of 90 mg/ L, contact time of 120 min, and dosage of 0.8 g/L. Regarding the adsorption kinetics, and a second-order equation resulted in the achievement of the best fit.
As the finding indicated, Arachis hypogaea ash as an inexpensive absorbent was a quite effective substance for the removal of aniline from water and wastewater.

The presence of antibiotics due to toxicity and sustainability as well as organic compounds as a combination of hard biodegradable wastewater is an undesirable issue in many industries. The aim of this study was to evaluate the efficiency of dissolved air flotation process for aniline and penicillin G removal from aqueous solutions.
This was an empirical-lab study to which the dissolved air flotation method was applied in laboratory scale. The effects of effective parameters including concentration of coagulant poly-aluminum chloride (PAC) (10, 20, 30, 40, 60 mg/L), coagulation time (5, 10, 15 and 20 minutes), flotation time (5, 10, 15 and 20 seconds) and saturation pressure (3, 3.5, 4 and 4, 5 atm) on the removal efficiency of aniline and penicillin G by dissolve air flotation were studied.
The results showed that dissolved air flotation method can reduce penicillin G and aniline up to 67.45% and 95%, respectively. The optimum condition was as follows: pH = 6, initial concentration of aniline = 200 mg/L, initial concentration of penicillin G = 25 mg/L, coagulation time = 10 minutes, flotation time = 10 seconds, pressure = 4 atm, and PAC concentration = 20 mg/L.
Dissolved air flotation process can be an effective method to remove aniline and penicillin G from aqueous solutions.

Introduction and Aniline and phenol are used in a wide range of industries, namely dye material, rubber, pesticide, plastic, and paint industries. These chemicals are released to the environment via effluent. This study aimed to investigate the efficiency of modified Pistacia terebinthus in removal of phenol and aniline from aqueous solutions.
In this experimental-laboratory study, effects of initial aniline and phenol concentrations, Pistacia terebinthus dosage, time, pH, and interference compounds on efficiency of aniline and phenol removal were investigated. Data evaluated for compliance with the isotherm (Langmuir, Freundlich, and Temkin) and kinetic (Pseudo second-order, Pseudo First-order and Intraparticcle diffusion) models
Our data showed that removal efficiency decreased with raising pH. The optimum condition for removal of aniline was pH=6, initial concentration= 50 mg/L, and contact time= 45 min, while for phenol it was pH=4, concentration= 50 mg/L, and contact time= 30 min. Adsorption isotherm data show that the fluoride sorption followed the freundlich isotherm. Aniline and phenol adsorption kinetics onto modified Pistacia terebinthus follows pseudo-second-order model.
Pistacia terebinthus is an effective factor in removal of aniline and phenol from water and effluent.

Dyes are one of the most important pollutants of textile industrial wastewater which are toxic, carcinogenic, teratogenic, and non-biodegredable. Basic red is the most commonly used pigment for dying. In this study, peanut shell ash was used as a low cost adsorbent for the removal of basic red 18 from aqueous solutions.
This research was conducted in bench scale in a batch reactor on synthetic wastewater. The effect of important parameters such as pH (2-12), reaction time (5-150 min), adsorbent dosage (0.02-1.2 g/l) and initial dye concentration (20-150 mg/l) on dye removal were evaluated. Also, the adsorption behavior of dye evaluated by Freundlich, Langmuir and Temkin isotherms.
Removal efficiency of 96.2 % was achieved at optimal pH equal to 11, contact time of 90 min, adsorbent dosage of 0.8 g/l and 60 mg/l initial dye concentration. With increasing dye concentration from 20 to 60 mg/l, removal efficiency was increased from 90.12% to 96.16%. The results of isotherm study showed that adsorption process of basic red 18 using peanut shell ash follows from Freundlich isotherm (R2=0.977).
The results showed that this material is an effective, natural and inexpensive adsorbent in treatment of wastewater containing basic red 18. Hence, using this material suggested for removal basic red 18 from aqueous solutions after additional studies.

Textile industry is regarded as one of the largest producers of dye and organic compounds, and Methylene Blue is the most commonly used dye material. In the present study, peanut shell powder was used as a low-cost adsorbent for removal of Methylene blue dye from aqueous solutions.
In this experimental study, effect of operating parameters including pH (2-12), reaction time (5-210 min), adsorbent dosage (0.1-1 g/l) and initial dye concentration (10-120 mg/l) were assessed on dye removal from synthetic wastewater. Moreover, the adsorption behavior of dye was evaluated by Freundlich and Langmuir isotherms.
Maximum removal efficiency of methylene blue was achieved at optimal pH of 11, reaction time of 75 min, adsorbent dosage of 8 g/l and initial dye concentration of 10 mg/l. With increasing dye concentration from 10 to 100 mg/l, removal efficiency was decreased from 99.5% to 96.46%. The obtained data demonstrated that adsorption process of Methylene blue using peanut shell powder was well fitted with Langmuir isotherms (R2=0.894).
Based on the results of the current study, the peanut shell seems to have an appropriate ability in Methylene blue dye removal from aqueous solution, and textile industry wastewater.

Scaling and corrosion are one the most important indices in water quality evaluation. On the other side, corrosion can effect on public health, acceptance of drinking water sources, costs of water supply. So, this study was performed with the aim of Determination of corrosion and scaling potential of drinking water in distribution system of Zabol using corrosion indices. In this cross-sectional study, the values of Langelier, Ryznar, Puckorius and aggressiveness indices were measured by determining of parameters such as temperature, calcium hardness, alkalinity, total dissolved solids and pH in 24 points of the distribution network system during 2013. All tests were done according to the methods mentioned in the standard methods for water and wastewater treatment. According to the Langelier index, in cold and warm seasons samples were sediment and corrosive, respectively. Based on the index Ryznar index samples were slightly and high corrosive in cold and warm seasons, respectively. Also, according to the Aggressiveness index water had medium corrosive at all seasons. Pokurious index showed that samples are corrosive. Based on the calculated mean of value for LSI (-0.3), RSI (8.03), AI (11.49), PI (7.24), drinking water in distribution system of Zabol are corrosive, sever corrosive, medium corrosive and corrosive, respectively. Based on the results of this study, water in distribution system of Zabol are corrosive that leads to Corrosion in the systems and facilities of water supply. It is necessary to planning of balancing water quality to be done to prevent economic damages.

Methylene blue (MB) is a most common paint for dying and it can cause eye burns, breathing problem, heart rate increasing, nausea, diarrhea, and vomiting, gastritis, shock, cyanosis, jaundice, quadriplegia, and tissue necrosis in humans. In this study, cumin stem powder has been used as a low cost adsorbent for the removal of Methylene blue dye from aqueous solutions. In this experimental study, the efficiency of cumin stem powder in removal of methylene blue and the effect of effecting operating parameters such as pH (2-12), reaction time (5-210 min), adsorbent dosage (0.1-2 g/l) and initial concentration of dye (10-100 mg/l) on color removal from synthetic wastewater were studied. The results showed that the maximum removal efficiency of methylene blue 93% was achieved at optimum condition: pH 11, reaction time 90 min, adsorbent dosage 0.5 g/l and initial dye concentration 100 mg/l. The results of isotherm study revealed well fitting of the experimental data with Freundlich (R2=0.9913). According to results of this study, it was found that the cumin stem powder has a high capacity to remove methylene blue dye from aqueous solution and textile industry wastewater.