The Efficiency of Electrocoagulation Process Using Iron Electrode in Removal of Humic Acid from Water in the Presence of Chitosan as a Coagulant Aid

Background: Natural organic substances in water cause problems during water treatment processes. The potential of these compounds as precursor of trihalomethanes formation has increased the necessity of removing these compounds from water more than ever. In the current study, the effect of chitosan, as a cheap and efficient coagulant, in the electrocoagulation process with iron electrode for removal of humic acid from aqueous solutions was evaluated. Methods: In this study, a batch reactor equipped with 4 iron electrodes in dimensions of 2*20*200 mm, with a volume of 1 L and connected to an electrical source was used. The effects of current density, initial humic acid concentration, chitosan concentration and pH in the electrocoagulation process were investigated. Excel software was used to analyze the obtained results. Results: The results indicated pH = 6, current density=40 V, and chitosan concentration= 2 mg/L as the optimal conditions for the process. Also, in the presence of chitosan as a coagulant aid in the electrocoagulation process, after 60 min, the process efficiency reached 68%. Conclusion: Based on the current findings, electrocoagulation process is a suitable process in removal of humic acid. Also, chitosan is an efficient coagulant aid in the electrocoagulation process with iron electrode and increases the process efficiency. Keywords: Electrocoagulation, Humic acid, Coagulant aid, Chitosa

Preparationandcatalyticactivityofbone-char ash decoratedwithMgO-FeNO3 for ozonation of reactiveblack5dyefromaqueoussolution: Taguchioptimizationdata

Reactivedyeisoneofthemostapplicabledyesintextileindustries which itsreleasetothewaterbodiescreatesaconcernforenvir- onmentalists. Here,inthisdataarticleabone-char(BC)ash decoratedwithMgO-FeNO3 for removingreactiveblack5(RB5) dyeinacatalyticozonationprocess(COP)system.Operational parametersdatasuchasinitialRB5concentration,pH,catalyst dosage, andreactiontimewereoptimizedusingTaguchimethod. The optimalconditionsforinitialRB5concentration,pH,catalyst dosage, andreactiontimeweredetermined10mg/L,10,0.1g/L, and 15min,respectively.DataofTaguchioptimizationtestsindi- cated thattheinitialRB5concentrationhadasignificant influence on RB5removalefficiency (54.03%)duringthecatalyticozonation process, andreactiontimehadlowercontributio

Investigation on effect of chitosan aid in removal of humic acid from aqueous solutions by electrocoagulation process using aluminum electrode

زمینه و هدف: وجود اسید هیومیک در آب آشامیدنی می تواند به عنوان یک ترکیب پیش ساز سبب تولید ترکیبات جانبی گندزدایی گردد. این مطالعه با هدف ارزیابی تأثیر کیتوزان به عنوان کمک منعقد کننده کم هزینه و موثر در فرآیند انعقاد الکتریکی به همراه الکترود آلومینیم، برای حذف ماده آلی اسید هیومیک از محیط های آبی انجام شده است. روش بررسی: در این مطالعه تجربی، آزمایشات انعقاد الکتریکی با الکترود آلومینیوم در pH های 10-2 با و بدون حضور کیتوزان مورد مطالعه قرار گرفت. اثرات مقادیر متغیر پارامتر های دانسیته جریان، غلظت اولیه اسید هیومیک وغلظت کیتوزان به عنوان کمک منعقد کننده در فرآیند انعقاد الکتریکی در یک راکتور پایلوت از جنس پلکسی گلاس با جریان ناپیوسته مورد بررسی قرار گرفت. در مراحل مختلف مطالعه، غلظت اسید هیومیک با استفاده از دستگاه اسپکتروفتومتر اندازه گیری شد. یافته ها: دانسیته جریان برابر با 20 میلی آمپر بر سانتی متر مربع و pH معادل 6 به عنوان شرایط بهینه برای حذف اسید هیومیک از محیط آبی بدون کیتوزان حاصل شد. همچنین حضور کیتوزان در غلظت mg/l 5/2 به عنوان کمک منعقد کننده در فرآیند انعقاد الکتریکی باعث حذف حداکثری میزان اسید هیومیک (90 درصد) گردید. نتیجه گیری: ماده کیتوزان به عنوان یک کمک منعقد کننده مناسب و موثر در فرآیند انعقاد الکتریکی در حضور الکترود آلومینیم عمل می کند و می تواند سبب افزایش کارایی فرایند های انعقادی در حدف ماده آلی اسید هیومیک گردد

Weather modification, solution and innovation to reservoirs water sustainable management (case study: ZayandeRoud reservoir)

Climate change has had devastating effects on water resources in many countries. Many volumes of Iran’s water resources have declined due to climate change. Meanwhile, the use of weather modification methods, especially cloud seeding, is a practical solution to adapt to the climate change impact. In Iran, consecutive droughts and climate change have reduced water resources of dams behind and in some cases, they have completely dried up. Nowadays, cloud seeding is used as the most costeffective method for water harvesting in the world… The results of the evaluation of cloud seeding projects in most parts of the country indicate an average runoff increase of between 10% and 15% during the seeding periods. Zayanderud Dam is one of the big dams in Iran in the Zagros Mountain range its water resources have been significantly reduced by overdraft and climate change. Cloud seeding operations have been performing for many years in the Charmahal and Bakhtiari catchment, which are located upstream of the ZayandeRoud reservoirs as new method to sustainable water resources management of dams. In this article, the results of runoff production by cloud seeding operation will be noted in the ZayandeRoud Dam for 10 years Non-consecutive (2006 – 2016)

CuCoFe2O4@AC magnetic nanocomposite as a novel heterogeneous Fenton-like nanocatalyst for Ciprofloxacin degradation from aqueous solutions

Abstract CuCoFe2O4@Activated Carbon (AC) was synthesized by a fast, simple, and green microwave-assisted coprecipitation method, and then used as a new heterogeneous magnetic nanocatalyst in Fenton-like reaction for ciprofloxacin (CIP) degradation from aqueous media. CuCoFe2O4@AC was characterized by Field emission scanning electron microscopy (FE-SEM), Energy-Dispersive Spectroscopy (EDS), Mapping, Line scan, Fourier-transform infrared spectroscopy (FT-IR), Thermal gravimetric analysis (TGA), X-Ray diffraction analysis (XRD), vibrating-sample magnetometer (VSM), and Brunauer–Emmett–Teller (BET) techniques. The characterization results showed that the CuCoFe2O4@AC nanocomposite was in the ferrite phase with a mesoporous, uniform, quasi-spherical surface and a particle size of about 25 nm. The total volume of single-point adsorption pores was equal to 0.22 cm3 g−1 and the specific surface area was determined to be 199.54 m2 g−1. This nanocomposite had good thermal stability with high magnetic strength. In the presence of H2O2, the synthesized nanocomposite provided a Fenton-like reaction for CIP removal from aqueous solutions. The investigation of this process showed that neutral pH, 1 g L−1 of the nanocomposite, and 73.5 mM of H2O2 were the optimal conditions for CIP removal with an initial CIP concentration of 20 mg L−1. The maximum removal efficiency of 95.77% was attained after 120 min of contact time under the optimum conditions. The CIP degradation during this Fenton-like process followed a pseudo-first-order kinetic model with rate constants (K app) of 0.01 min−1. Finally, the CIP removal efficiency after 5 cycles of recovery and regeneration of CuFe2O4@AC was 87.65%. The excellent performance and high catalytic activity of CuCoFe2O4@AC in Fenton-like reaction for CIP removal make it have potential application foreground in the treatment of pharmaceutical wastewater

Biosorption of Pentachlorophenol from Aqueous Solutions by Aspergillus Niger Biomass

Background: This study aimed to investigate the biosorption of pentachlorophenol on Aspergillus niger biomass as a method for removal of pentachlorophenol from aqueous solutions. Methods: Modified A. niger biomass with NaOH was used to absorb the pentachlorophenol. The impacts of various experimental parameters like primary pentachlorophenol concentration, pH of the solution, contact time, and biomass dosage on the biosorption of pentachlorophenol were investigated. Results: The correlation of contact time, pH and initial concentration with the biosorption of pentachlorophenol by A. niger biomass was statistically significant (P<0.001). Pentachlorophenol removal increased with decreasing pH of the solution and the maximum efficiency was obtained at pH=3. The equilibrium adsorption capacity was increased from 4.23 to 11.65 mg/g by increasing initial pentachlorophenol concentration from 10 to 40 mg/L, while pentachlorophenol removal efficiency decreased from 87 to 55%. Both Langmuir and Freundlich isotherms efficiently described adsorption equilibrium of pentachlorophenol on A. niger biomass. Correlation coefficients for the second order kinetic model were almost equal to one. Conclusion: A. niger biomass can be used to reduce the toxicity of aqueous solutions containing pentachlorophenol in acidic pH conditions