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Papers by Nady Passe-Coutrin

Research paper thumbnail of Role of acidic sites in beta-hexachlorocyclohexane (β-HCH) adsorption by activated carbons: molecular modelling and adsorption–desorption studies

RSC Adv., 2015

The removal of b-HCH from contaminated water by adsorption on activated carbons is presented. Sug... more The removal of b-HCH from contaminated water by adsorption on activated carbons is presented. Sugar cane bagasse activated carbons with different textural and surface chemical properties were prepared and characterized for studying the b-HCH adsorption process. The isotherms are correlated by six models, among which the Fowler-Guggenheim/Jovanovic-Freundlich model is found to provide the best fit for two of the studied activated carbons. The isotherm adsorption data were correlated with the surface functional group composition. b-HCH adsorption was favored by the presence of acidic groups at the AC surface of chemically activated carbons. A thorough theoretical exploration of the potential energy surface for the interaction of b-HCH with a graphene sheet alone or containing hydroxyl or carboxyl surface groups was carried out. Molecular modelling results showed that under neutral to slightly acidic conditions only carboxylic surface groups should significantly contribute to b-HCH adsorption, in qualitative agreement with the experimental results. The analysis of the most stable structures suggests that the hydrogen bonds between the axial hydrogens of b-HCH and the charged oxygens of the deprotonated acidic surface groups are the main interactions responsible for the adsorption. This result is confirmed by a Temperature-Programmed Desorption study, showing that b-HCH molecules are associated with carboxylic groups of the AC surface.

Research paper thumbnail of Improving of understanding of beta-hexachlorocyclohexane (HCH) adsorption on activated carbons by temperature-programmed desorption studies

Environmental science and pollution research international, Jan 28, 2015

In order to understand the interactions between beta-hexachlorocyclohexane (HCH) and chemical gro... more In order to understand the interactions between beta-hexachlorocyclohexane (HCH) and chemical groups at activated carbon (AC) surface, the solid samples were hydrogenated aiming to decrease the amounts of oxygenated groups. Two AC samples designated by BagH2O and BagP1.5 were prepared by water vapor activation and phosphoric acid activation, respectively, of sugarcane bagasse used as an AC precursor. A more simple molecule 1,2,3-trichloropropane (TCP) is used as a model of chlorinated compound. The AC were characterized by infrared, X-ray photoelectron spectroscopy (XPS), Raman resonance spectroscopies, as well as temperature-programmed desorption coupled with mass spectrometry (TPD-MS). BagP1.5 and BagH2O AC surface contained oxygenated groups. Upon hydrogenation, a decrease of most of these group amxounts was observed for both samples, while hydroxyl groups increased. On the basis of temperature-programmed desorption data obtained for AC samples contaminated with TCP or HCH, it wa...

Research paper thumbnail of Improving of understanding of beta-hexachlorocyclohexane (HCH) adsorption on activated carbons by temperature-programmed desorption studies

Environmental Science and Pollution Research, 2015

In order to understand the interactions between beta-hexachlorocyclohexane (HCH) and chemical gro... more In order to understand the interactions between beta-hexachlorocyclohexane (HCH) and chemical groups at activated carbon (AC) surface, the solid samples were hydrogenated aiming to decrease the amounts of oxygenated groups. Two AC samples designated by BagH2O and BagP1.5 were prepared by water vapor activation and phosphoric acid activation, respectively, of sugarcane bagasse used as an AC precursor. A more simple molecule 1,2,3-trichloropropane (TCP) is used as a model of chlorinated compound. The AC were characterized by infrared, X-ray photoelectron spectroscopy (XPS), Raman resonance spectroscopies, as well as temperature-programmed desorption coupled with mass spectrometry (TPD-MS). BagP1.5 and BagH2O AC surface contained oxygenated groups. Upon hydrogenation, a decrease of most of these group amxounts was observed for both samples, while hydroxyl groups increased. On the basis of temperature-programmed desorption data obtained for AC samples contaminated with TCP or HCH, it was possible to determine the type of hydrogen bond formed between each AC and HCH.

Research paper thumbnail of Parameters from a new kinetic equation to evaluate activated carbons efficiency for water treatment

Water Research, 2006

The fractal dimension of some commercial activated carbon (AC) was determined in the micro-, meso... more The fractal dimension of some commercial activated carbon (AC) was determined in the micro-, meso-and macropore range using mercury porosimetry and N 2 adsorption data.

Research paper thumbnail of Water desorption and aragonite—calcite phase transition in scleractinian corals skeletons

Thermochimica Acta, 1995

ABSTRACT Several authors have reported lower temperatures for the aragonite—calcite phase transit... more ABSTRACT Several authors have reported lower temperatures for the aragonite—calcite phase transition for the skeleton of scleractinian corals, when compared with those observed in the mineral aragonite. This phenomenon has been attributed to the hydration of the coral aragonite.Using differential scanning calorimetry coupled with thermogravimetry measurements, we have observed the existence of double endothermic peaks probably connected with two separate phenomena: water desorption, followed by the aragonite—calcite transition. Determination of the enthalpy of the first endothermic peak allowed us to predict the existence of hydrogen-bonding interactions between the oxygen atoms of the carbonate planes and the water molecules.

Research paper thumbnail of Comparison of parameters calculated from the BET and Freundlich isotherms obtained by nitrogen adsorption on activated carbons: A new method for calculating the specific surface area

Microporous and Mesoporous Materials, 2008

The empirical linear relationship between the BET surface area S BET and the Freundlich constant ... more The empirical linear relationship between the BET surface area S BET and the Freundlich constant K F , calculated from nitrogen adsorption isotherms of activated carbons, S BET = a 0 K F is mathematically demonstrated. This correlation exists in the relative pressure domain in which the BET equation is valid, whatever the value of c for the BET equation and for values of the Freundlich exponent, a, between 0 and 0.2. This study allows to determine the correlation factor a 0 = 1/a with a ¼ 1

Research paper thumbnail of Assessment of the surface area occupied by molecules on activated carbon from liquid phase adsorption data from a combination of the BET and the Freundlich theories

Journal of Colloid and Interface Science, 2009

A new equation is derived from a combination of the BET (Brunauer, Emmett, Teller) and Freundlich... more A new equation is derived from a combination of the BET (Brunauer, Emmett, Teller) and Freundlich isotherms fitted for liquid phase adsorption data on activated carbons. This equation, depending on the Freundlich parameters and the equilibrium adsorption-desorption constant can be used for assessment of the surface area occupied by the solute molecules on a surface in a liquid phase system under some conditions.

Research paper thumbnail of Textural analysis for better correlation of the char yield of pyrolysed lignocellulosic materials

Fuel, 2005

... Keywords: Char yield; Microporous char; Mercury porosimetry. Article Outline. ... The correla... more ... Keywords: Char yield; Microporous char; Mercury porosimetry. Article Outline. ... The correlation between a c and ε is not particularly simple. Mercury porosimetry allows to determine another parameter, the fractal dimension of the material surface area, independent on the scale. ...

Research paper thumbnail of Developing an Empirical Formula for the Assessment of the Char Yield of Pyrolyzed Lignocellulosic Materials

Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2007

A new empirical formula, based on the porosity, the botanical composition and the ash content of ... more A new empirical formula, based on the porosity, the botanical composition and the ash content of the precursor, is proposed for the assessment of the char yield, Y (wt%), of lignocellulosic materials pyrolyzed in a 600°C–900°C temperature range. The following equation is proposed: Y (wt%) = (0.8815 − 2.281/ϵ + 61.44/ϵ) · {[L(0.59 − 2.74 × 10 (t°C − 600)

Research paper thumbnail of Sugar cane bagasse fibres reinforced cement composites: Thermal considerations

Composites Part A: Applied Science and Manufacturing, 2010

This paper examines the thermal properties of cement composites reinforced with vegetable bagasse... more This paper examines the thermal properties of cement composites reinforced with vegetable bagasse fibres (1.5% and 3% wrtc).Thermal properties have been correlated to macroscopic density and porosity in order to estimate thermal conductivity of fibres using a calculation inspired from the Maxwell–Eucken modelling.Experimental investigations reveal that adding retified bagasse fibres reduces composites thermal conductivity and yields a weaker specific heat

Research paper thumbnail of CHAPTER 2. Activated Carbon from Biomass for Water Treatment

RSC Green Chemistry, 2013

Research paper thumbnail of Role of acidic sites in beta-hexachlorocyclohexane (β-HCH) adsorption by activated carbons: molecular modelling and adsorption–desorption studies

RSC Adv., 2015

The removal of b-HCH from contaminated water by adsorption on activated carbons is presented. Sug... more The removal of b-HCH from contaminated water by adsorption on activated carbons is presented. Sugar cane bagasse activated carbons with different textural and surface chemical properties were prepared and characterized for studying the b-HCH adsorption process. The isotherms are correlated by six models, among which the Fowler-Guggenheim/Jovanovic-Freundlich model is found to provide the best fit for two of the studied activated carbons. The isotherm adsorption data were correlated with the surface functional group composition. b-HCH adsorption was favored by the presence of acidic groups at the AC surface of chemically activated carbons. A thorough theoretical exploration of the potential energy surface for the interaction of b-HCH with a graphene sheet alone or containing hydroxyl or carboxyl surface groups was carried out. Molecular modelling results showed that under neutral to slightly acidic conditions only carboxylic surface groups should significantly contribute to b-HCH adsorption, in qualitative agreement with the experimental results. The analysis of the most stable structures suggests that the hydrogen bonds between the axial hydrogens of b-HCH and the charged oxygens of the deprotonated acidic surface groups are the main interactions responsible for the adsorption. This result is confirmed by a Temperature-Programmed Desorption study, showing that b-HCH molecules are associated with carboxylic groups of the AC surface.

Research paper thumbnail of Improving of understanding of beta-hexachlorocyclohexane (HCH) adsorption on activated carbons by temperature-programmed desorption studies

Environmental science and pollution research international, Jan 28, 2015

In order to understand the interactions between beta-hexachlorocyclohexane (HCH) and chemical gro... more In order to understand the interactions between beta-hexachlorocyclohexane (HCH) and chemical groups at activated carbon (AC) surface, the solid samples were hydrogenated aiming to decrease the amounts of oxygenated groups. Two AC samples designated by BagH2O and BagP1.5 were prepared by water vapor activation and phosphoric acid activation, respectively, of sugarcane bagasse used as an AC precursor. A more simple molecule 1,2,3-trichloropropane (TCP) is used as a model of chlorinated compound. The AC were characterized by infrared, X-ray photoelectron spectroscopy (XPS), Raman resonance spectroscopies, as well as temperature-programmed desorption coupled with mass spectrometry (TPD-MS). BagP1.5 and BagH2O AC surface contained oxygenated groups. Upon hydrogenation, a decrease of most of these group amxounts was observed for both samples, while hydroxyl groups increased. On the basis of temperature-programmed desorption data obtained for AC samples contaminated with TCP or HCH, it wa...

Research paper thumbnail of Improving of understanding of beta-hexachlorocyclohexane (HCH) adsorption on activated carbons by temperature-programmed desorption studies

Environmental Science and Pollution Research, 2015

In order to understand the interactions between beta-hexachlorocyclohexane (HCH) and chemical gro... more In order to understand the interactions between beta-hexachlorocyclohexane (HCH) and chemical groups at activated carbon (AC) surface, the solid samples were hydrogenated aiming to decrease the amounts of oxygenated groups. Two AC samples designated by BagH2O and BagP1.5 were prepared by water vapor activation and phosphoric acid activation, respectively, of sugarcane bagasse used as an AC precursor. A more simple molecule 1,2,3-trichloropropane (TCP) is used as a model of chlorinated compound. The AC were characterized by infrared, X-ray photoelectron spectroscopy (XPS), Raman resonance spectroscopies, as well as temperature-programmed desorption coupled with mass spectrometry (TPD-MS). BagP1.5 and BagH2O AC surface contained oxygenated groups. Upon hydrogenation, a decrease of most of these group amxounts was observed for both samples, while hydroxyl groups increased. On the basis of temperature-programmed desorption data obtained for AC samples contaminated with TCP or HCH, it was possible to determine the type of hydrogen bond formed between each AC and HCH.

Research paper thumbnail of Parameters from a new kinetic equation to evaluate activated carbons efficiency for water treatment

Water Research, 2006

The fractal dimension of some commercial activated carbon (AC) was determined in the micro-, meso... more The fractal dimension of some commercial activated carbon (AC) was determined in the micro-, meso-and macropore range using mercury porosimetry and N 2 adsorption data.

Research paper thumbnail of Water desorption and aragonite—calcite phase transition in scleractinian corals skeletons

Thermochimica Acta, 1995

ABSTRACT Several authors have reported lower temperatures for the aragonite—calcite phase transit... more ABSTRACT Several authors have reported lower temperatures for the aragonite—calcite phase transition for the skeleton of scleractinian corals, when compared with those observed in the mineral aragonite. This phenomenon has been attributed to the hydration of the coral aragonite.Using differential scanning calorimetry coupled with thermogravimetry measurements, we have observed the existence of double endothermic peaks probably connected with two separate phenomena: water desorption, followed by the aragonite—calcite transition. Determination of the enthalpy of the first endothermic peak allowed us to predict the existence of hydrogen-bonding interactions between the oxygen atoms of the carbonate planes and the water molecules.

Research paper thumbnail of Comparison of parameters calculated from the BET and Freundlich isotherms obtained by nitrogen adsorption on activated carbons: A new method for calculating the specific surface area

Microporous and Mesoporous Materials, 2008

The empirical linear relationship between the BET surface area S BET and the Freundlich constant ... more The empirical linear relationship between the BET surface area S BET and the Freundlich constant K F , calculated from nitrogen adsorption isotherms of activated carbons, S BET = a 0 K F is mathematically demonstrated. This correlation exists in the relative pressure domain in which the BET equation is valid, whatever the value of c for the BET equation and for values of the Freundlich exponent, a, between 0 and 0.2. This study allows to determine the correlation factor a 0 = 1/a with a ¼ 1

Research paper thumbnail of Assessment of the surface area occupied by molecules on activated carbon from liquid phase adsorption data from a combination of the BET and the Freundlich theories

Journal of Colloid and Interface Science, 2009

A new equation is derived from a combination of the BET (Brunauer, Emmett, Teller) and Freundlich... more A new equation is derived from a combination of the BET (Brunauer, Emmett, Teller) and Freundlich isotherms fitted for liquid phase adsorption data on activated carbons. This equation, depending on the Freundlich parameters and the equilibrium adsorption-desorption constant can be used for assessment of the surface area occupied by the solute molecules on a surface in a liquid phase system under some conditions.

Research paper thumbnail of Textural analysis for better correlation of the char yield of pyrolysed lignocellulosic materials

Fuel, 2005

... Keywords: Char yield; Microporous char; Mercury porosimetry. Article Outline. ... The correla... more ... Keywords: Char yield; Microporous char; Mercury porosimetry. Article Outline. ... The correlation between a c and ε is not particularly simple. Mercury porosimetry allows to determine another parameter, the fractal dimension of the material surface area, independent on the scale. ...

Research paper thumbnail of Developing an Empirical Formula for the Assessment of the Char Yield of Pyrolyzed Lignocellulosic Materials

Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2007

A new empirical formula, based on the porosity, the botanical composition and the ash content of ... more A new empirical formula, based on the porosity, the botanical composition and the ash content of the precursor, is proposed for the assessment of the char yield, Y (wt%), of lignocellulosic materials pyrolyzed in a 600°C–900°C temperature range. The following equation is proposed: Y (wt%) = (0.8815 − 2.281/ϵ + 61.44/ϵ) · {[L(0.59 − 2.74 × 10 (t°C − 600)

Research paper thumbnail of Sugar cane bagasse fibres reinforced cement composites: Thermal considerations

Composites Part A: Applied Science and Manufacturing, 2010

This paper examines the thermal properties of cement composites reinforced with vegetable bagasse... more This paper examines the thermal properties of cement composites reinforced with vegetable bagasse fibres (1.5% and 3% wrtc).Thermal properties have been correlated to macroscopic density and porosity in order to estimate thermal conductivity of fibres using a calculation inspired from the Maxwell–Eucken modelling.Experimental investigations reveal that adding retified bagasse fibres reduces composites thermal conductivity and yields a weaker specific heat

Research paper thumbnail of CHAPTER 2. Activated Carbon from Biomass for Water Treatment

RSC Green Chemistry, 2013