Sarathi R; Meenakshi Sundar S
Abstract
Titanium-di-oxide nanoparticles are synthesized via a microwave-assisted solvothermal route for different pH values. The effect of the acidic and basic nature of the solvent due to the pH value is reflected in the crystalline size of the compound. The purpose of this work is to synthesize Titanium dioxide ...
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Titanium-di-oxide nanoparticles are synthesized via a microwave-assisted solvothermal route for different pH values. The effect of the acidic and basic nature of the solvent due to the pH value is reflected in the crystalline size of the compound. The purpose of this work is to synthesize Titanium dioxide nanoparticles and to observe their application in degrading industrially contaminated water using normal tap water. The crystalline sizes are calculated using XRD analysis and confirmed with HRTEM. The chemical composition and oxidation state are confirmed with XPS studies. Optical properties are carried out with UV-Vis, FTIR, and PL spectra. Photocatalytic studies are carried out to degrade the dye in industrial water. The efficiency of degradation is calculated with the UV-Vis data and formula. The reduction in band gap and high permanence has greatly supported in making it acceptable for photocatalytic activity under visible light. Dependence of time, initial dye concentration, and pH of the dye solution on TiO2 as a catalyst is investigated under the illumination of a visible lamp, and degradation efficiency to the highest of 96.79% has been obtained.
Pranjal Saikia; Ananta Saikia; Binoy Kumar Saikia
Abstract
Removal of heavy metals from waste water is a need of the hour. Titanium dioxide (TiO2) nanoparticles were functionalized using succinic anhydride (SA) and adsorption of copper (II) on SA functionalized TiO2 nanoparticles (TiOSA) was carried out. The adsorption of Cu (II) on TiOSA was estimated with ...
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Removal of heavy metals from waste water is a need of the hour. Titanium dioxide (TiO2) nanoparticles were functionalized using succinic anhydride (SA) and adsorption of copper (II) on SA functionalized TiO2 nanoparticles (TiOSA) was carried out. The adsorption of Cu (II) on TiOSA was estimated with respect to pH, contact time and adsorbent dose. The study confirms the best removal of Cu (II) using the said adsorbent is at pH 8. The Cu (II) concentration can be reduced to less than 1.1 mg/L at contact time of 180 min with initial 15 mg/L Cu (II) concentration using adsorbent dose of 0.6 g/50 mL. The study reveals that the adsorption process preferably follows the Langmuir isotherm model. Also, the thermodynamic parameters like entropy change (∆S°), enthalpy change (∆H°) and free energy change (∆G°) were calculated for the adsorption process. The pseudo-second order kinetic model was found to be better fitted to the adsorption.
Azam Gholami; Mahmood Hajiani; Mohammad Hossein Sayadi Anari
Abstract
Contaminants of emerging concern or simply emerging contaminants have been considered as a critical environmental issue in recent decades. These compounds have not routinely controlled and monitored; therefore they have posed risk to health of human and environment. Drugs are considered as one of the ...
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Contaminants of emerging concern or simply emerging contaminants have been considered as a critical environmental issue in recent decades. These compounds have not routinely controlled and monitored; therefore they have posed risk to health of human and environment. Drugs are considered as one of the most important emerging pollutants. They introduce to environment form different sources such urine, human excretion, livestock, poultry, pharmaceutical, and hospitals. Although they are in trace levels, they are not biodegradable. They cannot be removed by conventional treatment processes. .. Advanced oxidation processes (AOPs) have been designed to address the deficiency of conventional methods in removal of emerging pollutants. Production of highly reactive hydroxyl radicals is the base of AOPs. These very reactive radicals effectively oxidize emerging pollutants such as drugs. Among different approach of AOPs, photocatalytic degradation has been successfully applied to mitigate the side effects of emerging contaminants. The ability of photocatalytic process in removal of Clindamycin hydrochloride (CLM) from aqueous solutions in the presence of UV/TiO2 was studied. The effects of various parameters such as adsorption, photolysis, pH, catalyst dosage, initial concentration of antibiotic, and radiation time were investigated in a batch photoreactor. Results showed that photolysis and adsorption had a negligible contribution to the clindamycin removal. The maximum clindamycin removal rate was obtained under optimal conditions, such as pH of 5, 0.5 g/l of TiO2, initial clindamycin concentration of 2 /L. This optimum condition was achieved during 90 minutes.. The CLM photocatalytic degradation kinetics showed that CLM degradation follows the pseudo-first-order kinetics.
Marjan Tanzifi; Marzieh Kolbadi nezhad; Kianoush Karimipour
Abstract
The present work seeks to investigate the ability of polypyrrole/titanium dioxide nanocomposite to adsorb cadmium ions from aqueous solution. The impact of various experimental conditions, including solution pH, adsorbent dosage, adsorption time and initial concentration on the uptake of cadmium were ...
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The present work seeks to investigate the ability of polypyrrole/titanium dioxide nanocomposite to adsorb cadmium ions from aqueous solution. The impact of various experimental conditions, including solution pH, adsorbent dosage, adsorption time and initial concentration on the uptake of cadmium were studied. The adsorption kinetic was studied with the first-order, second-order, pseudo-first-order, pseudo-second-order and Morris–Weber models. The results revealed that adsorption process is controlled by pseudo-second-order model which illustrated that the adsorption process of cadmium is chemisorption-controlled. The adsorption capacity obtained from this model is 20.49 mg/g which close to the experimental value. The study yielded the result that when the initial concentration of the solution changed from 20 mg/l to 120 mg/l, the adsorption capacity increased from 0.99 to 24.52 mg/g. Further, Langmuir, Freundlich and Temkin isotherm models were applied to investigate the adsorption isotherm. Based on the results of the adsorption isotherm, Freundlich isotherm proved to be the best fit with the experimental data. Also, the morphology, chemical structure and thermal stability of adsorbent were studied by using SEM, EDX, FTIR, and TGA.