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1.
Molecules ; 27(22)2022 Nov 14.
Article in English | MEDLINE | ID: mdl-36431944

ABSTRACT

In the present study, calcined melamine (CM) and magnetite nanoparticles (MNPs) were encapsulated in a calcium alginate (CA) matrix to effectively activate peroxymonosulfate (PMS) and generate free radical species for the degradation of ibuprofen (IBP) drug. According to the Langmuir isotherm model, the adsorption capacities of the as-prepared microcapsules and their components were insignificant. The CM/MNPs/CA/PMS process caused the maximum degradation of IBP (62.4%) in 30 min, with a synergy factor of 5.24. Increasing the PMS concentration from 1 to 2 mM improved the degradation efficiency from 62.4 to 68.0%, respectively, while an increase to 3 mM caused a negligible effect on the reactor effectiveness. The process performance was enhanced by ultrasound (77.6% in 30 min), UV irradiation (91.6% in 30 min), and electrochemical process (100% in 20 min). The roles of O•H and SO4•- in the decomposition of IBP by the CM/MNPs/CA/PMS process were 28.0 and 25.4%, respectively. No more than 8% reduction in the degradation efficiency of IBP was observed after four experimental runs, accompanied by negligible leachate of microcapsule components. The bio-assessment results showed a notable reduction in the bio-toxicity during the treatment process based on the specific oxygen uptake rate (SOUR).


Subject(s)
Magnetite Nanoparticles , Alginates , Anti-Inflammatory Agents, Non-Steroidal , Ibuprofen , Polymers , Water
2.
Ultrason Sonochem ; 67: 105114, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32278247

ABSTRACT

The main aim of the present investigation was the intercalation of WS2 nanosheets in the structure of ceria (CeO2) to be used for the efficient catalytic destruction of tylosin (TYL) as a macrolide antibiotic in water. As-synthesized heterostructured catalyst was placed in a sono-reactor (40 kHz and 300 W) in order to degrade TYL through the sonocatalysis. 15 wt% WS2/CeO2 was chosen for performing the systematic experiments. Decreasing the concentration of TYL, along with increasing the WS2/CeO2 dosage led to reduced degradation efficiency. The water hardness was demonstrated to be a suppressive agent on the sonocatalysis of the target pollutant. As-generated holes, OH, and also O2- were responsible for the degradation of TYL. Increasing the ultrasound power and operating temperature enhanced the degradation efficiency. The degradation rate boosted up when the temperature was raised from 10 °C (0.0107 1/min) to 40 °C (0.0165 1/min). Moreover, the lowest activation energy (Ea) for sonocatalytic degradation was obtained as 10.81 kJ/mol. The sonocatalytic activity of WS2/CeO2 in the sono-reactor encountered insignificant change within five consecutive operational runs (~15% reduction). The mechanism and pathways of the sonocatalytic decomposition of TYL are also proposed.

3.
Colloids Surf B Biointerfaces ; 189: 110878, 2020 May.
Article in English | MEDLINE | ID: mdl-32087528

ABSTRACT

In this research, a milk thistle seed extract (MTSE)-rich medium was used as a capping and reducing agent for the one-pot biosynthesis of ZnO/Ag (5 wt%) nanostructure. The sample was systematically characterized through various techniques and its strong biomolecule‒metal interface structure was supported by the results. The efficacy of the derived nanostructure (MTSE/ZnO/Ag) was evaluated in vivo on the basis of its therapeutic effects on the main complications of Type 1 diabetes (hyperglycemia, hyperlipidemia, and insulin deficiency). For this purpose, the changes in the plasma values of fasting blood glucose, total cholesterol, total triglyceride, high-density lipoprotein cholesterol, and insulin in alloxan-diabetic Wistar male rats were compared with those in healthy and untreated diabetic controls after a treatment period of 16 days. The antidiabetic results of MTSE/ZnO/Ag were compared with those obtained from pristine ZnO, MTSE, and insulin therapies. The health conditions of the rats with Type 1 diabetes were significantly enhanced after treatment with MTSE/ZnO/Ag (p < 0.05), which is owing to the enhanced interface structure and participatory functions of the united compartments of MTSE/ZnO/Ag.


Subject(s)
Diabetes Complications/drug therapy , Diabetes Mellitus, Type 1/drug therapy , Hypoglycemic Agents/therapeutic use , Nanocomposites/chemistry , Plant Extracts/therapeutic use , Silybum marianum/chemistry , Alloxan , Animals , Diabetes Complications/chemically induced , Diabetes Mellitus, Experimental/chemically induced , Diabetes Mellitus, Experimental/drug therapy , Diabetes Mellitus, Type 1/chemically induced , Hypoglycemic Agents/chemistry , Hypoglycemic Agents/isolation & purification , Male , Molecular Structure , Particle Size , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Rats , Rats, Wistar , Seeds/chemistry , Silver/chemistry , Surface Properties , Zinc Oxide/chemistry
4.
J Environ Manage ; 224: 315-326, 2018 Oct 15.
Article in English | MEDLINE | ID: mdl-30056351

ABSTRACT

In the present investigation, the treatment of amoxicillin (AMX)-polluted water by the activated persulfate (PS) was considered. As a novel research, continuously electro-generated magnetite (Fe3O4) nanoparticles (CEMNPs) were utilized as the activator of PS in an electrochemical medium. The PS/CEMNPs displayed a remarkable enhancement in the decomposition of AMX molecules up to 72.6% compared with lonely PS (24.8%) and CEMNPs (13.4%). On the basis of pseudo-first order reaction rate constants, the synergy percent of about 70% was achieved due to the combination of PS with CEMNPs. The adverse influence of free radical-scavenging compounds on the efficiency of the PS/CEMNPs process was in the following order: carbonate < chloride < tert-butyl alcohol < ethanol. Overall, these results proved the main role of free radical species in degrading AMX. The implementation of ultrasound (US) enhanced the performance of the PS/CEMNPs process. Nevertheless, the highest degradation efficiency of about 94% was achieved when UV254 lamp was joined the PS/CEMNPs system. Under UV254 and US irradiation, the results showed significant potential of the PS/CEMNPs process for degrading AMX antibiotic and generating low toxic effluent based on the activated sludge inhibition test. However, more time is needed to achieve the acceptable mineralization.


Subject(s)
Amoxicillin/isolation & purification , Nanoparticles , Water Purification , Anti-Bacterial Agents , Ferrosoferric Oxide , Oxidation-Reduction , Water Pollutants, Chemical
5.
Chemosphere ; 210: 699-708, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30032000

ABSTRACT

The aim of the present study was to employ martite nanoparticles synthesized through planetary ball milling instead of conventional sources of iron for the activation of Oxone in order to decompose tetracycline (TC) antibiotic in the aquatic phase. Accordingly, martite nanoparticles-activated Oxone exhibited a remarkable improvement in degrading TC molecules up to 87%. The results indicated an increased decomposition rate of TC with increasing Oxone concentration, martite nanoparticles dosage, and initial pH. In the absence of ultrasound, the decomposition rate of TC was 0.0481 min-1 within 30 min, while the implementation of ultrasound at 320 W and addition of hydrogen peroxide at 40 mM led to increase in the decomposition rate up to 0.0770 and 0.0907 min-1, respectively. The presence of carbonate and even persulfate ions suppressed the decomposition rate. Inversely, the addition of chloride and carbon tetrachloride enhanced the reactor performance in terms of TC degradation. Within four consecutive experimental runs, only 10.8% was dropped in the decomposition rate, indicating the appropriate reusability potential of martite nanoparticles. The results confirmed the appropriate ability of the treatment process in degrading and mineralizing the target pollutant but a longer exposure time is required for an efficient mineralization.


Subject(s)
Environmental Restoration and Remediation/methods , Iron/chemistry , Nanoparticles/chemistry , Sulfuric Acids/chemistry , Tetracyclines/chemistry , Anti-Bacterial Agents/pharmacology , Hydrogen Peroxide/pharmacology , Ultrasonic Waves , Water Pollutants, Chemical/analysis
6.
J Colloid Interface Sci ; 522: 228-241, 2018 Jul 15.
Article in English | MEDLINE | ID: mdl-29604441

ABSTRACT

In the present work, ultrasonically facilitated adsorption (UFA) of a cationic dye [Basic Red 46 (BR46)] was examined using cellulosic nanostructures obtained from broom and cooler straw. Although the exclusive application of the nanostructured broom resulted in the 43.51% adsorption of BR46, the UFA process gave rise to the substantial removal efficiency of about 93%. In the case of the nanostructured straw, the efficiency was increased from 36.9% to 55.7%. The UFA process for both adsorbents reached the equilibrium within 60 min which was shorter than the time for the only adsorption. According to the values of the mean free energy (E), the decolorization via the UFA process applying broom (15.81 kJ/mol) and straw (11.18 kJ/mol) nanostructures was occurred chemically. An insignificant loss in the adsorption capacity of both adsorbents was observed after three regeneration tests by means of 0.05 M hydrochloric acid, indicating the good reusability potential of the as-synthesized cellulosic nanostructures.

7.
Chemosphere ; 194: 471-480, 2018 Mar.
Article in English | MEDLINE | ID: mdl-29232640

ABSTRACT

The main aim of the present investigation was the treatment of ibuprofen (IBP)-polluted aquatic phase using a novel oxygen-permeable cathode (OPC)-equipped electrochemical process (ECP) integrated with ultrasound (US). According to kinetic modeling, the decomposition rate of IBP by the integrated process was 3.2 × 10-2 min-1 which was significant in comparison with the OPC-equipped ECP (1.4 × 10-2 min-1) and US alone (2.4 × 10-3 min-1). Increasing the current resulted in the enhanced generation of H2O2 and consequently, improved the degradation of IBP in the solution. Excessive concentrations of Na2SO4 as supporting electrolyte led to no significant enhancement in the reactor efficiency. At initial IBP concentration of 1 mg L-1, complete removal of IBP with reaction rate of 1.7 × 10-1 min-1 was happened within a short reaction time of 30 min. The pulse mode of US led to more than 10% increase in the removal efficiency compared with the normal mode. The presence of scavenging compound of methanol caused the highest drop in the efficiency of the integrated treatment process, indicating the substantial role of free hydroxyl radicals in the degradation of IBP. Intermediate byproducts generated in the solution during the decomposition were also identified and interpreted.


Subject(s)
Electrochemical Techniques/methods , Ibuprofen/analysis , Sonication , Water Pollutants, Chemical/analysis , Water Purification/methods , Carbon/chemistry , Electrochemical Techniques/instrumentation , Electrodes , Hydrogen Peroxide/chemistry , Hydroxyl Radical/chemistry , Kinetics , Models, Theoretical , Nanoparticles/chemistry , Oxygen/chemistry , Soot/chemistry
8.
Data Brief ; 14: 20-27, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28761913

ABSTRACT

Soil is an important component of life cycle affecting agriculture and food crops. Quality of soil resources is defined according to their potential impact on human health by exposure of harmful constituents through the food chain. Heavy metals especially As, Pb and Cd are among the most hazardous elements which could be released to the top soil through different wastewaters, fertilizers, herbicides and etc. In this research Aghili plain in Khuzestan province, Iran was selected as a total of 54 samples were prepared based on a systematic gridding procedure. Selected heavy metals concentrations were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) and then zoning was performed using kriging method. Pollution level was assessed through single factor indices and pollution load index. A separate map dealing with each heavy metal was prepared to present the distribution of heavy metal in Aghili plain. In all samples the heavy metals concentrations were followed the bellow trend: Pb>As>Cd. Furthermore, based on the PLI, all stations were categorized as moderately to highly polluted sites (1

9.
Environ Sci Pollut Res Int ; 24(17): 15157-15166, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28500548

ABSTRACT

The application of a novel nanocomposite synthesized through the combination of Fe3O4 nanoparticles and bone char particles for the adsorption of As(V) ions in the aquatic medium was investigated. As-prepared nanocomposite was immobilized by using chitosan biopolymer. The characterization of the nanocomposite was performed via SEM, XRD, FT-IR, and BET together with the determination of zero-point charge of the adsorbent surface. As results, the obtained experimental data were fitted well with pseudo-first-order kinetic model (R2 = 0.997) and Langmuir isotherm model (R2 = 0.990) with the maximum adsorption capacity of about 112 µg/g. Increasing the dosage of nanocomposite and initial solute concentration led to increasing the adsorption capacity of As(V) ions, while decreasing the solution temperature resulted in the enhanced adsorption process. According to the results of thermodynamic study, the adsorption of As(V) ions onto the nanocomposite was spontaneous and exothermic in nature.


Subject(s)
Arsenic/chemistry , Chitosan/chemistry , Nanocomposites , Water Pollutants, Chemical/chemistry , Adsorption , Decontamination , Hydrogen-Ion Concentration , Kinetics , Spectroscopy, Fourier Transform Infrared
10.
J Environ Manage ; 191: 198-208, 2017 Apr 15.
Article in English | MEDLINE | ID: mdl-28104552

ABSTRACT

Treatment of a saline petrochemical wastewater with BOD5/COD ratio of less than 0.1 was investigated using a consortium consisted of three isolated salt-tolerant bacteria namely, Kocuria turfanesis, Halomonas alkaliphila and Pseudomonas balearica. Selected bacteria were isolated from petrochemical wastewater containing mineral salt mediums of 3% salinity. A lab-scale activated sludge bioreactor was used for startup in batch mode operation and after obtaining the MLSS concentration of about 3000 mg/L, the operation was changed to continuous flow mode to determine the biokinetic coefficients under different organic loading rates of 0.33-1.21 kg CODm-3 d-1. The COD removal efficiency of 78.7%-61.5% was observed for treatment of real saline wastewater with a decreasing trend along with increasing the organic loading rate. In addition, results of kinetic investigation demonstrated that the yield(Y), endogenous decay coefficient (kd), maximum reaction rate (Kmax), maximum specific growth rate (µmax) and saturation constant (Ks) were 0.54 mg VSS mg COD-1, 0.014 day-1, 1.23 day-1, 0.66 day-1, and 1315 mg L-1, respectively.


Subject(s)
Biodegradation, Environmental , Wastewater , Bioreactors/microbiology , Sewage , Sodium Chloride , Waste Disposal, Fluid
11.
J Environ Manage ; 187: 111-121, 2017 Feb 01.
Article in English | MEDLINE | ID: mdl-27888712

ABSTRACT

This study was performed to assess the efficiency of silica nanopowder (SNP)/milk vetch-derived charcoal (MVDC) nanocomposite coupled with the ultrasonic irradiation named sono-adsorption process for treating water-contained Basic Red 46 (BR46) dye. Field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) and Fourier transform infrared spectroscopy (FT-IR) were performed for the characterization of as-prepared adsorbent. The sono-assisted adsorption process was optimized using response surface optimization on the basis of central composite design by the application of quadratic model. Accordingly, the color removal can be retained more than 93% by an initial BR46 concentration of 8 mg/L, sonication time of 31 min, adsorbent dosage of 1.2 g/L and initial pH of 9. The pseudo-second order kinetic model described the sono-assisted adsorption of BR46 reasonably well (R2 > 0.99). The intra-particular diffusion kinetic model pointed out that the sono-assisted adsorption of BR46 onto SNP/MVDC nanocomposite was diffusion controlled as well as that ultrasonication enhanced the diffusion rate.


Subject(s)
Astragalus Plant/chemistry , Azo Compounds/isolation & purification , Coloring Agents/isolation & purification , Nanocomposites/chemistry , Water Pollutants, Chemical/isolation & purification , Adsorption , Azo Compounds/chemistry , Charcoal/chemistry , Coloring Agents/chemistry , Diffusion , Hydrogen-Ion Concentration , Kinetics , Models, Theoretical , Silicon Dioxide/chemistry , Spectroscopy, Fourier Transform Infrared , Textile Industry , Ultrasonics/methods , Waste Disposal, Fluid/methods , Water Pollutants, Chemical/chemistry , X-Ray Diffraction
12.
Ultrason Sonochem ; 35(Pt A): 210-218, 2017 Mar.
Article in English | MEDLINE | ID: mdl-27707646

ABSTRACT

Nano-sized siderite was used as catalyst for the heterogeneous Fenton process combined with ultrasonic irradiation to degrade reactive yellow 81 (RY-81) in the aqueous phase. As the most efficient process, nano-sized siderite prepared via ball milling was chosen to carry out the experiments. 6h milled siderite at initial pH of 3.0 led to the highest removal efficiency of 92.09% within the reaction time of 30min. At a short reaction time of 20min, increasing siderite nanoparticles dosage from 0.3 to 0.75g/L resulted in increasing removal efficiency from 49.82 to 79.86%, respectively, while further increase in the dosage caused a substantial decrease in the efficiency. In the case of the effect of solute concentration, increasing the dye up to 400mg/L led to a significant decrease in the removal efficiency (65.77%). The presence of 0.01M Na2CO3 and C2H5OH significantly diminished the decolorization efficiency of RY-81 (<10%) with initial concentration of 100mg/L. The intermediates produced during the treatment process were also identified using GC-MS analysis. This research suggested that ball milled siderite is a potential catalyst for the efficient decolorization of textile effluents via ultrasound-assisted Fenton process.

13.
J Environ Manage ; 179: 47-57, 2016 Sep 01.
Article in English | MEDLINE | ID: mdl-27173890

ABSTRACT

The scope of this study was the use of bentonite as the carrier of ZnO nanoparticles for enhancing the sonocatalytic decolorization of Basic Red 46 (BR46) in the aqueous phase. The results demonstrated the higher sonocatalytic activity of bentonite-supported ZnO nanoparticles (BSZNs) in comparison with the suspended ZnO nanoparticles (SZNs). The particle size of BSZNs (5-40 nm) was lower than that of SZNs (20-120 nm). Due to the immobilization of ZnO nanoparticles, a specific surface area of 80.6 m(2)/g was obtained for the BSZNs, which was higher than the specific surface area of the raw bentonite (42.2 m(2)/g). Optimization of the process via response surface methodology (RSM) based on central composite design (CCD) showed the maximum sonocatalytic decolorization efficiency (%) of 89.92% in which the initial dye concentration, the ZnO/bentonite ratio, the sonocatalyst dosage, and the initial pH were 6 mg/L, 0.3, 2.5 g/L and 9, respectively. The byproducts generated during the sonocatalysis of BR46 over BSZNs were identified using gas chromatography-mass spectrometry (GC-MS) analysis. From an application viewpoint, the sonocatalysis of real textile wastewater resulted in a COD removal efficiency (%) of about 44% within a reaction time of 150 min.


Subject(s)
Bentonite/chemistry , Nanoparticles/chemistry , Textile Industry , Waste Disposal, Fluid/methods , Zinc Oxide/chemistry , Azo Compounds/chemistry , Catalysis , Ultrasonics/methods , Wastewater/chemistry
14.
Ultrason Sonochem ; 32: 181-190, 2016 09.
Article in English | MEDLINE | ID: mdl-27150759

ABSTRACT

The improvement of sonocatalytic treatment of real textile wastewater in the presence of MgO nanoparticles was the main goal of the present study. According to our preliminary results, the application of pulse mode of sonication, together with the addition of periodate ions, produced the greatest sonocatalytic activity and consequently, the highest chemical oxygen demand (COD) removal efficiency (73.95%) among all the assessed options. In the following, pulsed sonocatalysis of real textile wastewater in the presence of periodate ions was evaluated response surface methodologically on the basis of central composite design. Accordingly, a high correlation coefficient of 0.95 was attained for the applied statistical strategy to optimize the process. As results, a pulsed sonication time of 141min, MgO dosage of 2.4g/L, solution temperature of 314K and periodate concentration of 0.11M gave the maximum COD removal of about 85%. Under aforementioned operational conditions, the removal of total organic carbon (TOC) was obtained to be 63.34% with the reaction rate constant of 7.1×10(-3)min(-1) based on the pseudo-first order kinetic model (R(2)=0.99). Overall, periodate-assisted pulsed sonocatalysis over MgO nanoparticles can be applied as an efficient alternative process for treating and mineralizing real textile wastewater with good reusability potential.


Subject(s)
Nanoparticles , Periodic Acid , Wastewater , Textile Industry , Textiles , Waste Disposal, Fluid
15.
J Environ Manage ; 177: 111-8, 2016 Jul 15.
Article in English | MEDLINE | ID: mdl-27086271

ABSTRACT

Sequencing coagulation - photocatalytic degradation using UVA/MgO nanoparticles process was investigated for Acid red 73dye removal and then treatment of a real textile wastewater. Effective operational parameters including pH and coagulant and photocatalyst dosage were studied in synthetic wastewater and then the process was applied for real wastewater. Both coagulation and photocatalytic processes were pH dependent. At coagulant dosage of 200 mg/L and initial pH of 6, the dye concentration decreased from 200 to 31 mg/L. Complete removal of AR73 was observed with MgO nanoparticles of 0.8 g/L, initial pH of 5 and reaction time of 60 min. Langmuir-Hinshelwood model was well fitted with removal results (R(2): 0.939-0.988 for different initial dye concentration). In the case of real textile wastewater, the sequence coagulation-UVA/MgO nanoparticles photocatalytic degradation yielded considerable total COD and TOC removal 98.3% and 86.9%respectively, after 300 min.


Subject(s)
Azo Compounds/chemistry , Coloring Agents/chemistry , Metal Nanoparticles/chemistry , Naphthalenesulfonates/chemistry , Textile Industry , Waste Disposal, Fluid/methods , Biological Oxygen Demand Analysis , Catalysis , Hydrogen-Ion Concentration , Magnesium Oxide/chemistry , Photochemical Processes , Ultraviolet Rays , Wastewater/chemistry
16.
Ultrason Sonochem ; 30: 123-31, 2016 May.
Article in English | MEDLINE | ID: mdl-26615797

ABSTRACT

The present study focused on the synthesis of nanostructured MgO via sonochemical method and its application as sonocatalyst for the decolorization of Basic Red 46 (BR46) dye under ultrasonic irradiation. The sonocatalyst was characterized using X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM) equipped with energy dispersive X-ray microanalysis (EDX). In the following, the sonocatalytic removal of the dye under different operational conditions was evaluated kinetically on the basis of pseudo first-order kinetic model. The reaction rate of sonocatalyzed decolorization using MgO nanostructures (12.7 × 10(-3) min(-1)) was more efficient than that of ultrasound alone (2.0 × 10(-3) min(-1)). The increased sonocatalyst dosage showed better sonocatalytic activity but the application of excessive dosage should be avoided. The presence of periodate ions substantially increased the decolorization rate from 14.76 × 10(-3) to 33.4 × 10(-3) min(-1). Although the application of aeration favored the decolorization rate (17.8 × 10(-3) min(-1)), the addition of hydrogen peroxide resulted in a considerable decrease in the decolorization rate (9.5 × 10(-3) min(-1)) due to its scavenging effects at specific concentrations. Unlike alcoholic compounds, the addition of phenol had an insignificant scavenging effect on the sonocatalysis. A mineralization rate of 7.4 × 10(-3) min(-1) was obtained within 120 min. The intermediate byproducts were also detected using GC-MS analysis.

17.
Ultrason Sonochem ; 28: 69-78, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26384885

ABSTRACT

In the present study, a porous clay-like support with unique characteristics was used for the synthesis and immobilization of ZnO nanostructures to be used as sonocatalyst for the sonocatalytic decolorization of methylene blue (MB) dye in the aqueous phase. As a result, the sonocatalytic activity of ZnO-biosilica nanocomposite (77.8%) was higher than that of pure ZnO nanostructures (53.6%). Increasing the initial pH from 3 to 10 led to increasing the color removal from 41.8% to 88.2%, respectively. Increasing the sonocatalyst dosage from 0.5 to 2.5 g/L resulted in increasing the color removal, while further increase up to 3g/L caused an obvious drop in the color removal. The sonocatalysis of MB dye over ZnO-biosilica nanocomposite was temperature-dependent. The presence of methanol produced the most adverse effect on the sonocatalysis of MB dye. The addition of chloride and carbonate ions had a negligible effect on the sonocatalysis, while the addition of persulfate ion led to increasing the color removal from 77.8% to 99.4% during 90 min. The reusability test exhibited a 15% drop in the color removal (%) within three consecutive experimental runs. A mineralization efficiency of 63.2% was obtained within 4h.

18.
Ultrason Sonochem ; 22: 371-81, 2015 Jan.
Article in English | MEDLINE | ID: mdl-24931424

ABSTRACT

Undoped and Pr-doped ZnO nanoparticles were prepared using a simple sonochemical method, and their sonocatalytic activity was investigated toward degradation of Acid Red 17 (AR17) under ultrasonic (US) irradiation. Synthesized nanoparticles were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) techniques. The extent of sonocatalytic degradation was higher compared with sonolysis alone. The decolorization efficiency of sonolysis alone, sonocatalysis with undoped ZnO and 5% Pr-doped ZnO was 24%, 46% and 100% within reaction time of 70min, respectively. Sonocatalytic degradation of AR17 increased with increasing the amount of dopant and catalyst dosage and decreasing initial dye concentration. Natural pH was favored the sonocatalytic degradation of AR17. With the addition of chloride, carbonate and sulfate as radical scavengers, the decolorization efficiency was decreased from 100% to 65%, 71% and 89% at the reaction time of 70min, respectively, indicating that the controlling mechanism of sonochemical degradation of AR17 is the free radicals (not pyrolysis). The addition of peroxydisulfate and hydrogen peroxide as enhancer improved the degradation efficiency from 79% to 85% and 93% at the reaction time of 50min, respectively. The result showed good reusability of the synthesized sonocatalyst.

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