Showing papers by "Saeid Ahmadzadeh published in 2018"

Removal of acetaminophen from hospital wastewater using electro-Fenton process

Abstract: The current work deals with efficient removal of acetaminophen (AC) from hospital wastewater using electro-Fenton (EF) process. The degradation yield of 99.5% was obtained under optimal experimental conditions, namely 5.75 mg L−1 initial AC concentration, 2.75 pH solution, 3-cm inter-electrode distance, 100 mg L−1 KCl electrolyte, 122.5 µL L−1 H2O2, 8 mA cm−2 current density at equilibrium time of 8 min. Analysis of variance (ANOVA) suggested that the effect of mentioned operating parameters was statistically significant on the AC removal. The low probability amount of P value (P < 0.0001), the Fisher’s F-value of 65.91, and correlation coefficient of the model (R2 = 0.9545) revealed a satisfactory correlation between the experimental and the predicted values of AC removal. The predicted removal efficiency of 99.4% was in satisfactory agreement with the obtained experimental removal efficiency of 98.7%. The AC degradation during the EF followed a first-order kinetic model with rate constants (Kapp) of 0.6718 min−1. Using the ordinary radical scavengers revealed that main mechanism of AC degradation controlled by the hydroxyl free radicals produced throughout the EF process. The excess amount of iron (II) scavenged the active radicals and diminished the concentration of ·OH available to react with AC. The optimum molar ratio of H2O2 to Fe2+ was found to be 2.5. The developed EF process as a promising technique applied for treatment of real samples.

In situ generation of hydroxyl radical for efficient degradation of 2,4-dichlorophenol from aqueous solutions.

Abstract: Since 2,4-dichlorophenol (2,4-DCP) as a priority pollutant is used in numerous industrial processes, its removal from the aqueous environment is of utmost importance and desire. Herein, the authors describe an electrochemical treatment process for efficient removal of 2,4-DCP from aqueous solutions using electro-Fenton (EF) process. Response surface methodology (RSM) was applied to optimize the operating parameters. Analysis of variance (ANOVA) confirmed the significance of the predicted model. The effect of independent variables on the removal of 2,4-DCP was investigated and the best removal efficiency of 98.28% achieved under the optimal experimental condition including initial pH of 3, H2O2 dosage of 80 μL, initial 2,4-DCP concentration of 3.25 mg L−1, current density of 3.32 mA cm−2, and inter-electrode distance of 5.04 cm. The predicted removal efficiency was in satisfactory agreement with the obtained experimental removal efficiency of 99.21%. According to the obtained polynomial model, H2O2 dosage revealed the most significant effect on degradation process. The kinetic investigation revealed that the first-order model with the correlation coefficient of 0.9907 and rate constant (Kapp) of 0.831 min−1 best fitted with the experimental results. Generation of the hydroxyl radicals throughout the EF process controlled the degradation process.

Delayed death following paraquat poisoning: three case reports and a literature review.

Abstract: Paraquat (PQ) poisoning is principally reported in developing countries. However, most fatalities occur elsewhere due to the induction of multi-organ failure. PQ poisoning can hardly be managed by clinical practice, and no specific antidote has come into existence yet. Here three cases, including 17-, 20-, and 23-year-old men, who were poisoned with PQ, have been reported. Furthermore, the literature regarding biological mechanisms, clinical manifestation, and treatment of PQ-induced toxicity was reviewed. Patients who, either intentionally or accidentally, ingested PQ earlier were initially found to be stable at the emergency department (ED). Therefore, they were discharged from the hospital under a follow-up. However, after several days, the patients were referred to the hospital for the second time and despite cardiovascular resuscitation (CPR) efforts, they suddenly expired. The delayed death following exposure to PQ was reported for inducing gradual progressive pulmonary fibrosis, metabolic acidosis, neurotoxicity, renal failure, and liver injury in poisoned patients. Therefore, PQ-intoxicated patients should be supervised for up to several weeks, and kept in the hospital for a longer period of time. Clinical manifestations and laboratory findings are beneficial markers that act as useful predictors of PQ poisoning.

Microniosomes for concurrent doxorubicin and iron oxide nanoparticles loading; preparation, characterization and cytotoxicity studies.

Abstract: The current work deals with developing a suitable drug delivery system of doxorubicin (DOX) for intraperitoneal chemotherapy using niosomes through formulating non-ionic surfactants consisting of Brij™ 52, span™ 60 and Solulan™ C24. Entrapping the magnetite nanoparticles in the hydrophilic parts of niosomes was accompanied with high-efficient DOX loading by the current novel remote-loading method. Cytotoxicity of the prepared formulations was evaluated in vitro against A549 and PC-12 cell lines using the colorimetric WST-1 assay test. The obtained results revealed that, the cytotoxicity of DOX increased up to 22% especially on A549 cells by the current delivery system.

Phthalates as Emerging Pollutants in Water Environment: Control & Treatment Strategies

Abstract: Emerging pollutants (EPs) refer compounds that have not previously have been detected in water or sewage or their concentrations aren’t detectable. Nonetheless, today they are detected in water and sewage. The EPs include pharmaceuticals compounds such as antibiotics and hormone, plasticizers such as phthalates, surfactants, some herbicides, and flame retardants worldwide 1, 2 . Developing in industry, agriculture, and medicine, as well as increasing human needs for survival, has increased production and consumption of these materials. The excessive use of these compounds has led to the release of these pollutants into the drinking water and aquatic ecosystems 3 . An important class of emerging pollutants is phthalates. Phthalates are extensively used in plastic industries in order to increase the flexibility and quality of products. They are also used in cosmetics products, shampoo, soap, toys, and etc. Approximately 60 types of phthalates are produced in the universe. Phthalate diethylhexyl (PDE), phthalate dibutyl (PDB), and phthalate dimethyl (PDM) are the most important compounds that are used in industries. 4, 5 . Since most phthalate compounds have hydrophobic interaction, low solubility properties, and also chemical reactions phthalate are very weak with other components, therefore they are easily released into the aqueous environment. Phthalates have been detected in the air, soil, surface water, and groundwater. It was reported the maximum amount of Phthalates are in the range of ng to μg per liter, and ng.g -1

Modeling of Electro Fenton Process for Removal of Diazinon from Groundwater Using Response Surface Methodology

Abstract: Background: Diazinon is one of the most important pesticides extremely used in agriculture. Since these compounds are resistant to biodegradation, the arrival of these compounds to water resources has become a serious environmental problem. Therefore, in the current work, the removal of diazinon from groundwater was investigated using advanced oxidation processes electro Fenton. Methods: the current work was conducted in lab scale. The effect of operating parameters such as initial concentration of diazinon (1-30 mg.L-1), pH solution(3-9), current density (1-10 mA.cm-2), reaction time (3-30 min), and dosage of H2O2 (20-100 mL.L-1) were investigated. Response surface methodology (RSM) was used to optimize the parameters and suggested model was analyzed using ANOVA. Results: On the optimum condition including initial diazinon concentration of 6.88 mg.L-1, pH solution of 3, the reaction time of 10 min, the current density of 8.18 mA.cm-2, and dosage H2O2 of 83.78 mL.L-1 removal efficiency of diazinon was found to be 98.5 . Electrical energy consumption (EEC) was found to be 0.524 kWh.m-3. Moreover, the concentration of diazinon in groundwater was found to be 0.934p0.053 mg.L-1. Conclusion: According to the obtained results, electro Fenton process was found to be an efficient technique for successful removal of diazinon and other resistant ungradable organic compound from water sources. n

Simultaneous Voltammetric Determination of Ascorbic Acid, Hydroquinone, Kojic Acid, and Arbutin in Pharmaceutical Samples; a New Approach for Quantitative Determination of Niosomal Formulations Loading Efficiency

Abstract: Introduction: Arbutin (ABU) inhibits tyrosinase and thus prevents the formation of melanin, therefore, it used as a skin-lightening agent. Ascorbic acid (AA) used in therapeutical fields such as improving immunity, skin disorders, amelioration of injuries and burns. Hydroquinone (HQ) as one of the important skin-bleaching agents used to lighten areas of darkened skin such as freckles, melasma, age spots, and acne scars. Moreover, owing to ability of Kojic acid (KA) in preventing melanin formation, it used in whitening products because of this ability to limit melanin production. Due to the importance of quantitative determination of the four above mention drugs loading efficiency in niosomal formulations, a great attempt was made in the current work to provide a promising sensor using voltammetric techniques. Methods and Results: BMITB/NiO/NPs/MCPE was prepared by mixing 0.2 g of 1-butyl-3-methylimidazoliumtetrafluoroborate (BMITB) as a binder, 0.8 g of paraffin, 0.1 g of NiO nanoparticles and 0.9 g of graphite powder. The electro-oxidation signals of ABU, KA, AA, and HQ were increased at the surface of modified sensor compared to the bare electrode. The obtained result shows that, at pH 7.0 phosphate buffer (0.1 M), the catalytic oxidation signals exhibited a wide linear range with a satisfactory low detection limit. Conclusions: The proposed sensor revealed good electrocatalytic activity towards ABU, KA, AA, and HQ. The proposed modified carbon paste electrode (BMITB/NiO/NPs/MCPE) was applied successfully for simultaneous analysis of trace amount of four above mention drugs in niosome carrier real samples. Keywords: Drug analysis, Voltammetric sensor, NiOnanoparticle, Modified carbon paste electrode.