The inhibition performance of quercetin for C38 steel in1.0MHCl was evaluated by electrochemical ... more The inhibition performance of quercetin for C38 steel in1.0MHCl was evaluated by electrochemical measurements: impedance spectroscopy and polarization curves tests. Results obtained reveal that the quercetin acts excellently as a corrosion inhibitor for C38 steel in 1.0 M HCl. The inhibition efficiency increases with the concentration of the inhibitor to reach 98.2 % at 2.10-6M of the quercetin. Polarization curves showed that the quercetin behaves as a mixed-type inhibitor. The adsorption of the inhibitor on the carbon steel surface obeyed the Langmuir adsorption isotherm. The effect of temperature on the corrosion behavior of carbon steel in 1M HCl was also studied. EIS spectra exhibit one capacitive loop and confirm the inhibitive ability. Data obtained from EIS technique, were analyzed to model the corrosion inhibition process through appropriate equivalent circuit model; a constant phase element (CPE) has been used. The activation energy as well as other thermodynamic parameters for the inhibition process was calculated and discussed. Quantum chemical parameters were calculated using ab initio and DFT methods to find a good correlation with the inhibition efficiency. A good agreement was found between the theoretical calculations and experimental observations.
The influence of oil of citrus leaves (OCL) concentration and the effect of medium temperature on... more The influence of oil of citrus leaves (OCL) concentration and the effect of medium temperature on the carbon steel corrosion in aqueous 1.0 M hydrochloric acid was realized experimentally using electrochemical impedance spectroscopy, potentiodynamic polarization curves and gravimetric technique. Results showed that the OCL is the excellent inhibitor for steel corrosion and the polarization curves data revealed that the tested compound acts as a mixed type inhibitor with predominant anodic. The study of temperature effect was investigated and leads to the determination of thermodynamic activation parameters. Electrochemical impedance spectroscopy result exhibit one capacitive loop indicating that, the corrosion reaction is controlled by charge transfer process and the presence of this compound decreases the double layer capacitance and increases the charge transfer resistance. The oil of citrus leaves act by adsorption on the carbon steel surface according to a Langmuir isotherm adsorption model.
In this study, evaluation and comparison of the effectiveness of some photochemical systemssuch a... more In this study, evaluation and comparison of the effectiveness of some photochemical systemssuch as direct UV photolysis, H2O2/UV, H2O2/Fe2+(Fenton process)and H2O2/Fe2+/UV (Photo-Fenton process) have been investigated in lab-scale experiments to remove Neutral Red(abbreviated as NR)from aqueous solutions. From the experimental results, it has been found that color removal followed the increasing order: Direct UV photolysis < H2O2/UV
Pyridinium derivatives namely, 4-(dimethylamino)-1-ethylpyridinium bromide (DEB), 4-(dimethylamin... more Pyridinium derivatives namely, 4-(dimethylamino)-1-ethylpyridinium bromide (DEB), 4-(dimethylamino)-1- pentylpyridinium bromide (DPB) synthesised by our group, were tested as inhibitors for the corrosion of mild steel in 1 M HCl using polarisation and electrochemical impedance measurements, Scanning electron microscope (SEM) and Quantum chemical calculations. The results show that the DEB and DPB enhances inhibition at all concentrations. The best protection (94.09%) is obtained by adding DEB at 10-4 M. Polarisation curves show that DEB and DPB acts as a mixed type inhibitor. The degree of the surface coverage of the adsorbed inhibitors is determined by weight loss measurement, and it was found that the adsorption of the two compounds on the mild steel surface obeys the Langmuir adsorption isotherm. The effect of the temperature on the corrosion behaviour with addition of DEB and DPB at various concentrations was studied in the temperature range 303 – 333 K. Results show that the ra...
The acid corrosion inhibition and adsorption process of copper in 2M H3PO4 containing 0.3M of NaC... more The acid corrosion inhibition and adsorption process of copper in 2M H3PO4 containing 0.3M of NaCl by an Ecofriendly ionic liquid newly synthesized [1-(2-(4-chlorophenyl)-2 oxoethyl)Pyridazinium Bromid CPEPB] and [1-(2- (4-nitrophenyl)-2-oxoethyl)Pyridazinium Bromide NPEPB]. Was studied by using weight loss measurements, electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization.The presence of these tow molecules led to decrease of the corrosion rate of Copper. At 10-3 M of NPEPB and CPEPB, the inhibition efficiencies increase with the inhibitor concentration to reach 88.94% and 87.5%, respectively. The adsorption of these compounds on Copper surface agrees Langmuir’s adsorption isotherm. To support the experimental results and To perform the corrosion study, Quantum chemical approach, using the density functional theory (DFT), was applied in order to get better understanding about the relationship between the inhibition efficiency and molecular structure of NPEP...
The inhibition effect of 8-(4-chlorophenyl)-3-hydro xy-4,6-dioxo-2-(p-toly)-4,6-dihydropyrimido [... more The inhibition effect of 8-(4-chlorophenyl)-3-hydro xy-4,6-dioxo-2-(p-toly)-4,6-dihydropyrimido [2,1-b] [1,3] thiazine-7-carbonitrile ( HPDTC-1), 3-hydroxy-4,6-dioxo-8-phenyl-2-(p-toly)-4,6-dihyd ropyrimido [2,1-b] [1,3] thiazine-7-carbonitrile ( HPDTC-2) and 3-hydroxy8-(4-nitrophenyl)-4,6-dioxo-2-(p-toly )-4,6-dihydropyrimido [2,1b] [1,3] thiazine-7-carbonitrile ( HPDTC-3) on the corrosion behavior of carbon steel in hydr ochloric solution were investigated by experimentally using polarizat ion, electrochemical impedance spectroscopy and gra vimetric measurements and complementary with density functio nal theory (DFT) methods. The results of this study show that these compounds give excellent inhibiting propertie s for carbon steel corrosion in acidic medium with the efficiency that exceeds 96% for HPDTC-3, 95% for HPDTC-2 and 9 2% for HPDTC-1 at 10 -3 mol/L. Polarization curves prove that these organic compounds act as inhibitors mixe d-type. The adsorption of all studied inhibito...
This paper explores the degradation of a model pollutant, 2-(4-thiazolyl) benzimidazole by electr... more This paper explores the degradation of a model pollutant, 2-(4-thiazolyl) benzimidazole by electrochemical process. The degradation of the real Agricola effluent is followed by COD abatement and UV spectroscopy. The electrochemical oxidation of fungicide thiabendazole has been studied on boron doped diamond (BDD) electrodes on acid medium by bulk electrolysis. The influence of several operating parameters, such as applied current density, effect of electrolytes (NaCl), effect of concentration and effect of temperature was investigated. UV spectroscopy and chemical oxygen demand measurements were conducted to study the reaction kinetics of thiabendazole mineralization. The results showed that the rate of the electrooxidation increases with increasing current density and decreasing NaCl. The overall results indicated that BDD electrode exhibited the best performance.
The inhibition performance of quercetin for C38 steel in1.0MHCl was evaluated by electrochemical ... more The inhibition performance of quercetin for C38 steel in1.0MHCl was evaluated by electrochemical measurements: impedance spectroscopy and polarization curves tests. Results obtained reveal that the quercetin acts excellently as a corrosion inhibitor for C38 steel in 1.0 M HCl. The inhibition efficiency increases with the concentration of the inhibitor to reach 98.2 % at 2.10-6M of the quercetin. Polarization curves showed that the quercetin behaves as a mixed-type inhibitor. The adsorption of the inhibitor on the carbon steel surface obeyed the Langmuir adsorption isotherm. The effect of temperature on the corrosion behavior of carbon steel in 1M HCl was also studied. EIS spectra exhibit one capacitive loop and confirm the inhibitive ability. Data obtained from EIS technique, were analyzed to model the corrosion inhibition process through appropriate equivalent circuit model; a constant phase element (CPE) has been used. The activation energy as well as other thermodynamic parameters for the inhibition process was calculated and discussed. Quantum chemical parameters were calculated using ab initio and DFT methods to find a good correlation with the inhibition efficiency. A good agreement was found between the theoretical calculations and experimental observations.
The influence of oil of citrus leaves (OCL) concentration and the effect of medium temperature on... more The influence of oil of citrus leaves (OCL) concentration and the effect of medium temperature on the carbon steel corrosion in aqueous 1.0 M hydrochloric acid was realized experimentally using electrochemical impedance spectroscopy, potentiodynamic polarization curves and gravimetric technique. Results showed that the OCL is the excellent inhibitor for steel corrosion and the polarization curves data revealed that the tested compound acts as a mixed type inhibitor with predominant anodic. The study of temperature effect was investigated and leads to the determination of thermodynamic activation parameters. Electrochemical impedance spectroscopy result exhibit one capacitive loop indicating that, the corrosion reaction is controlled by charge transfer process and the presence of this compound decreases the double layer capacitance and increases the charge transfer resistance. The oil of citrus leaves act by adsorption on the carbon steel surface according to a Langmuir isotherm adsorption model.
In this study, evaluation and comparison of the effectiveness of some photochemical systemssuch a... more In this study, evaluation and comparison of the effectiveness of some photochemical systemssuch as direct UV photolysis, H2O2/UV, H2O2/Fe2+(Fenton process)and H2O2/Fe2+/UV (Photo-Fenton process) have been investigated in lab-scale experiments to remove Neutral Red(abbreviated as NR)from aqueous solutions. From the experimental results, it has been found that color removal followed the increasing order: Direct UV photolysis < H2O2/UV
Pyridinium derivatives namely, 4-(dimethylamino)-1-ethylpyridinium bromide (DEB), 4-(dimethylamin... more Pyridinium derivatives namely, 4-(dimethylamino)-1-ethylpyridinium bromide (DEB), 4-(dimethylamino)-1- pentylpyridinium bromide (DPB) synthesised by our group, were tested as inhibitors for the corrosion of mild steel in 1 M HCl using polarisation and electrochemical impedance measurements, Scanning electron microscope (SEM) and Quantum chemical calculations. The results show that the DEB and DPB enhances inhibition at all concentrations. The best protection (94.09%) is obtained by adding DEB at 10-4 M. Polarisation curves show that DEB and DPB acts as a mixed type inhibitor. The degree of the surface coverage of the adsorbed inhibitors is determined by weight loss measurement, and it was found that the adsorption of the two compounds on the mild steel surface obeys the Langmuir adsorption isotherm. The effect of the temperature on the corrosion behaviour with addition of DEB and DPB at various concentrations was studied in the temperature range 303 – 333 K. Results show that the ra...
The acid corrosion inhibition and adsorption process of copper in 2M H3PO4 containing 0.3M of NaC... more The acid corrosion inhibition and adsorption process of copper in 2M H3PO4 containing 0.3M of NaCl by an Ecofriendly ionic liquid newly synthesized [1-(2-(4-chlorophenyl)-2 oxoethyl)Pyridazinium Bromid CPEPB] and [1-(2- (4-nitrophenyl)-2-oxoethyl)Pyridazinium Bromide NPEPB]. Was studied by using weight loss measurements, electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization.The presence of these tow molecules led to decrease of the corrosion rate of Copper. At 10-3 M of NPEPB and CPEPB, the inhibition efficiencies increase with the inhibitor concentration to reach 88.94% and 87.5%, respectively. The adsorption of these compounds on Copper surface agrees Langmuir’s adsorption isotherm. To support the experimental results and To perform the corrosion study, Quantum chemical approach, using the density functional theory (DFT), was applied in order to get better understanding about the relationship between the inhibition efficiency and molecular structure of NPEP...
The inhibition effect of 8-(4-chlorophenyl)-3-hydro xy-4,6-dioxo-2-(p-toly)-4,6-dihydropyrimido [... more The inhibition effect of 8-(4-chlorophenyl)-3-hydro xy-4,6-dioxo-2-(p-toly)-4,6-dihydropyrimido [2,1-b] [1,3] thiazine-7-carbonitrile ( HPDTC-1), 3-hydroxy-4,6-dioxo-8-phenyl-2-(p-toly)-4,6-dihyd ropyrimido [2,1-b] [1,3] thiazine-7-carbonitrile ( HPDTC-2) and 3-hydroxy8-(4-nitrophenyl)-4,6-dioxo-2-(p-toly )-4,6-dihydropyrimido [2,1b] [1,3] thiazine-7-carbonitrile ( HPDTC-3) on the corrosion behavior of carbon steel in hydr ochloric solution were investigated by experimentally using polarizat ion, electrochemical impedance spectroscopy and gra vimetric measurements and complementary with density functio nal theory (DFT) methods. The results of this study show that these compounds give excellent inhibiting propertie s for carbon steel corrosion in acidic medium with the efficiency that exceeds 96% for HPDTC-3, 95% for HPDTC-2 and 9 2% for HPDTC-1 at 10 -3 mol/L. Polarization curves prove that these organic compounds act as inhibitors mixe d-type. The adsorption of all studied inhibito...
This paper explores the degradation of a model pollutant, 2-(4-thiazolyl) benzimidazole by electr... more This paper explores the degradation of a model pollutant, 2-(4-thiazolyl) benzimidazole by electrochemical process. The degradation of the real Agricola effluent is followed by COD abatement and UV spectroscopy. The electrochemical oxidation of fungicide thiabendazole has been studied on boron doped diamond (BDD) electrodes on acid medium by bulk electrolysis. The influence of several operating parameters, such as applied current density, effect of electrolytes (NaCl), effect of concentration and effect of temperature was investigated. UV spectroscopy and chemical oxygen demand measurements were conducted to study the reaction kinetics of thiabendazole mineralization. The results showed that the rate of the electrooxidation increases with increasing current density and decreasing NaCl. The overall results indicated that BDD electrode exhibited the best performance.
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