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Guilherme Luiz Dotto - One of the best experts on this subject based on the ideXlab platform.
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Novel biochar and hydrochar for the adsorption of 2-Nitrophenol from aqueous solutions: An approach using the PVSDM model.
Chemosphere, 2020Co-Authors: P.s. Pauletto, Guilherme Luiz Dotto, J. Moreno-pérez, L.e. Hernández-hernández, A. Bonilla-petriciolet, Nina Paula Gonçalves SalauAbstract:Abstract Two new adsorbents, namely avocado-based hydrochar and LDH/bone-based biochar, were developed, characterized, and applied for adsorbing 2-Nitrophenol. The pore volume and surface diffusion model (PVSDM) was numerically solved for different geometries and applied to interpret the adsorption decay curves. Both adsorbents presented interesting textural and physicochemical characteristics, which achieved maximum adsorption capacities of 761 mg/g for biochar and 562 mg/g for hydrochar. The adsorption equilibrium data were well fitted by Henry isotherm. Besides, thermodynamic investigation revealed endothermic adsorption with the occurrence of electrostatic interactions. PVSDM predicted the adsorption decay curves for different adsorbent geometries at different initial concentrations of 2-Nitrophenol. The surface diffusion was the main intraparticle mass transport mechanism. Furthermore, the external mass transfer and surface diffusion coefficients increased with the increase of 2-Nitrophenol concentration.
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Origin of the outstanding performance of ZnAl and MgFe layered double hydroxides in the adsorption of 2-Nitrophenol: A statistical physics assessment
Journal of Molecular Liquids, 2020Co-Authors: Lotfi Sellaoui, Guilherme Luiz Dotto, Michael Badawi, Adrian Bonilla-petriciolet, Zhuqi ChenAbstract:Abstract This paper describes the adsorption of toxic pollutant 2-Nitrophenol on Zn Al and Mg Fe layered double hydroxides. Mechanistic interpretation was provided via a statistical physics assessment. Experimental and theoretical results indicated that both adsorbents exhibit high adsorption capacities at saturation. In particular, the 2-Nitrophenol adsorption capacities were 556, 629, 695 and 710 mg/g for Zn Al-LDH and 362, 603, 648 and 650 mg/g for Mg Fe-LDH in the temperature range of 298–328 K. Zn–Al-LDH showed an outstanding performance to remove 2-Nitrophenol compared to other adsorbents of the literature having adsorption capacities below 100 mg/g. Adsorption mechanisms were analyzed via the calculation of the bonded number of 2-Nitrophenol molecules by the adsorbent functional group, the adsorption energy and the density of these functional groups. It was demonstrated that this organic compound was adsorbed via total non-horizontal (i.e., total inclined position) and mixed (horizontal and non-horizontal) orientations depending on adsorption temperatures and tested adsorbent. Calculated adsorption energies indicated an endothermic removal mechanism involving physical interactions. Modeling analysis concluded that the steric parameters ‘bonded number of adsorbate molecules per adsorbent (parameter n)’ and ‘density of functional groups (parameter Dm)’ were the relevant parameters to control the 2-Nitrophenol adsorption mechanism.
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Adsorptive potential of Zn–Al and Mg–Fe layered double hydroxides for the removal of 2–Nitrophenol from aqueous solutions
Journal of Environmental Chemical Engineering, 2020Co-Authors: Fabíola B. Dalla Nora, Victor V. C. Lima, Marcos L.s. Oliveira, Ahmad Hosseini-bandegharaei, Thiago A. L. Burgo, Luca Meili, Guilherme Luiz DottoAbstract:Abstract Two layered double hydroxides (LDH) of the type Zn–Al and Mg–Fe were synthesized, characterized and used as adsorbents to uptake 2–Nitrophenol (2–NP) from aqueous solutions. XRD, FTIR, SEM, EDS, AFM and N2 adsorption/desorption curves were used to characterize the Zn–Al–LDH and Mg–Fe–LDH. The potential of both layered double hydroxides to adsorb 2–NP was investigated by adsorption kinetics, equilibrium, thermodynamics and consecutive adsorption/desorption cycles. The characterization indicated a high crystallinity degree and a well–organized and lamellar structure, confirming the efficiency of the synthesis. Elovich was the better kinetic model to describe the 2–NP adsorption onto Zn–Al–LDH, while Pseudo–second order was the best for Mg–Fe–LDH. For both LDHs, the adsorption equilibrium followed the Freundlich model. The process was endothermic, being the maximum adsorption capacities of 290 and 165 mg g–1 for Zn–Al–LDH and Mg–Fe–LDH, respectively. LDHs can be applied for five adsorption/desorption cycles with excellent adsorption capacities. It can be concluded that Zn–Al–LDH and Mg–Fe–LDH are promising materials to treat waters and wastewaters containing 2–Nitrophenol
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understanding the adsorption mechanism of phenol and 2 Nitrophenol on a biopolymer based biochar in single and binary systems via advanced modeling analysis
Chemical Engineering Journal, 2019Co-Authors: Lotfi Sellaoui, Guilherme Luiz Dotto, Adrian Bonillapetriciolet, Abdelmottaleb Ben LamineAbstract:Abstract In this paper, the adsorption of phenol and 2-Nitrophenol on a biopolymer-based biochar in single and binary systems was investigated at 298–328 K and pH 5. Experimental results indicated that the adsorption capacities of phenol were significantly reduced from single to binary systems compared to those obtained for 2-Nitrophenol. This experimental evidence suggested an antagonistic effect between both adsorbates generating an inhibitive adsorption. In terms of modeling analysis, the single and binary adsorption isotherms were well reproduced by monolayer and competitive monolayer statistical physics models, respectively. These two models showed that phenol and 2-Nitrophenol molecules have been mainly docked with an inclined and horizontal positions in single and binary systems, respectively. A detailed analysis of the number of captured phenol (n1) and 2-Nitrophenol (n2) molecules per site in the binary systems demonstrated that its corresponding evolution varied with a completely inverse way thus corroborating the inhibition effect between phenol and 2-Nitrophenol molecules. The monolayer and competitive monolayer models were used to estimate two adsorption energies to characterize the single and binary adsorption mechanisms. The analysis of the energetic parameters suggested that the adsorption process was a physisorption. The interpretation of all monolayer and competitive monolayer model parameters provided new insights that contributed to understand the single and binary adsorption mechanisms of phenol and 2-Nitrophenol molecules on tested adsorbent.
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Adsorption of 2-Nitrophenol using rice straw and rice husks hydrolyzed by subcritical water.
Bioresource technology, 2019Co-Authors: Ederson R. Abaide, Guilherme Luiz Dotto, Marcus V. Tres, Giovani L. Zabot, Marcio A. MazuttiAbstract:Abstract The potential of rice husks and straw as adsorbents after being processed by subcritical water hydrolysis (SWH) was investigated. The influences of temperature (453, 493 and 533 K) and liquid/solid ratio (7.5 and 15 g water/g biomass) on the rice straw and rice husks characteristics and on the adsorption capacity of 2-Nitrophenol were evaluated at pH 4 and 7. Adsorption kinetics, equilibrium and thermodynamic parameters were also studied. The adsorption capacity was favored at pH 7. Pseudo-first-order model was suitable to predict the kinetic curves for 2-Nitrophenol concentrations of 25, 50, 75 and 100 mg/L and the isotherm data obeyed the Freundlich model. Overall, the thermodynamic results revealed a spontaneous and exothermic process. The maximum adsorption capacity (92.97 ± 1.31 mg/g) was obtained for rice straw that has undergone an SWH at 453 K and 7.5 g water/g straw. The integration of processes to valorize co-products can make the production of cellulosic bioethanol more feasible.
Pankaj Kumar Arora - One of the best experts on this subject based on the ideXlab platform.
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Diversity of 4-Chloro-2-Nitrophenol-Degrading Bacteria in a Waste Water Sample
Journal of Chemistry, 2016Co-Authors: Pankaj Kumar Arora, Alok Srivastava, Vijay SinghAbstract:Eighteen bacterial strains, isolated from a waste water sample collected from a chemically contaminated site, Patancheru (17°32′N 78°16′E/17.53°N 78.27°E), India, were able to decolorize 4-chloro-2-Nitrophenol (4C2NP) in the presence of an additional carbon source. These eighteen 4C2NP-decolorizing strains have been identified as members of four different genera, including Bacillus, Paenibacillus, Pseudomonas, and Leuconostoc based on the 16S rRNA gene sequencing and phylogenetic analysis. Most of the bacteria (10) belonged to the genus Bacillus and contributed 56% of the total 4C2NP-degrading bacteria, whereas the members of genera Paenibacillus and Pseudomonas represented 22% and 17%, respectively, of total 4C2NP-degrading isolates. There was only one species of Leuconostoc capable of degrading 4C2NP. This is the first report of the diversity of 4C2NP-decolorizing bacteria in a waste water sample. Furthermore, one bacterium, Bacillus aryabhattai strain PC-7, was able to decolorize 4C2NP up to a concentration of 2.0 mM. Gas chromatography-mass spectrometry analysis identified 5-chloro-2-methylbenzoxazole as the final product of 4C2NP decolorization in strain PC-7.
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Chemotaxis Away from 4-Chloro-2-Nitrophenol, 4-Nitrophenol, and 2,6-Dichloro-4-Nitrophenol by Bacillus subtilis PA-2
Journal of Chemistry, 2015Co-Authors: Pankaj Kumar Arora, Mi-jeong JeongAbstract:Bacterial strain PA-2 exhibits chemotaxis away from 4-chloro-2-Nitrophenol, 4-Nitrophenol, and 2,6-dichloro-4-Nitrophenol. This strain was identified as Bacillus subtilis on the basis of the 16S rRNA gene sequencing. The drop plate assay and the chemical-in-plug method were used to demonstrate negative chemotactic behavior of strain PA-2. The growth studies showed that strain PA-2 did not utilize 4-chloro-2-Nitrophenol, 4-Nitrophenol, and 2,6-dichloro-4-Nitrophenol as its sole sources of carbon and energy. This is the first report of negative chemotaxis of 4-chloro-2-Nitrophenol, 4-Nitrophenol, and 2,6-dichloro-4-Nitrophenol by any bacterium.
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Biotransformation and chemotaxis of 4-chloro-2-Nitrophenol by Pseudomonas sp. JHN
Microbial cell factories, 2014Co-Authors: Pankaj Kumar Arora, Hanhong BaeAbstract:Pseudomonas sp. JHN decolourized and biotransformed 4-chloro-2-Nitrophenol (4C2NP) in the presence of additional carbon source. The effect of the various concentrations of the 4C2NP was studied on the decolourization of 4C2NP by Pseudomonas sp. JHN. It was observed that strain JHN decolourized and biotransformed 4C2NP up to concentration of 0.6 mM. Gas chromatography and gas chromatography-mass spectrometry detected 5-chloro-2-methylbenzoxazole as a major metabolite of the co-metabolism of 4C2NP. Furthermore, strain JHN exhibits positive chemotaxis toward 4C2NP based on the drop plate and capillary assays. This is the first report of the chemotaxis toward 4C2NP by any bacterium.
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Decolourization of 4-chloro-2-Nitrophenol by a soil bacterium, Bacillus subtilis RKJ 700.
PloS one, 2012Co-Authors: Pankaj Kumar AroraAbstract:A 4-Chloro-2-Nitrophenol (4C2NP) decolourizing strain RKJ 700 was isolated from soil collected from a pesticide contaminated site of India and identified as Bacillus subtilis on the basis of the 16S rRNA gene sequence analysis. Bacillus subtilis RKJ 700 decolourized 4C2NP up to concentration of 1.5 mM in the presence of additional carbon source. The degradation pathway of 4C2NP was studied and 4-chloro-2-aminophenol, 4-chloro-2-acetaminophenol and 5-chloro-2-methylbenzoxazole (5C2MBZ) were identified as metabolites by high performance liquid chromatography and gas chromatography-mass spectrometry. Resting cell studies showed that Bacillus subtilis RKJ 700 depleted 4C2NP completely with stoichiometric formation of 5C2MBZ. This is the first report of (i) the degradation of 4C2NP at high concentration (1.5 mM) and, (ii) the formation of 5C2MBZ by a soil bacterium.
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Metabolism of 4-chloro-2-Nitrophenol in a Gram-positive bacterium, Exiguobacterium sp. PMA
Microbial cell factories, 2012Co-Authors: Pankaj Kumar Arora, Ashutosh Sharma, Richa Mehta, Belle Damodara Shenoy, Alok Srivastava, Vijay SinghAbstract:Background ChloroNitrophenols (CNPs) are widely used in the synthesis of dyes, drugs and pesticides, and constitute a major group of environmental pollutants. 4-Chloro-2-Nitrophenol (4C2NP) is an isomer of CNPs that has been detected in various industrial effluents. A number of physicochemical methods have been used for treatment of wastewater containing 4C2NP. These methods are not as effective as microbial degradation, however.
Mathew R. Heal - One of the best experts on this subject based on the ideXlab platform.
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Experimentally determined Henry's Law coefficients of phenol, 2-methylphenol and 2-Nitrophenol in the temperature range 281–302 K
Atmospheric Environment, 2002Co-Authors: Mark Harrison, J. Neil Cape, Mathew R. HealAbstract:Abstract The Henry's Law coefficient is a key physical parameter in the partitioning, and hence environmental fate, of a chemical species between air and water. Despite the acknowledged polluting potential of phenol, 2-methylphenol (o-cresol) and 2-Nitrophenol, there is extremely poor agreement in the literature of their Henry's law coefficients and, in particular, no apparent systematic measurement of the variation with temperature. Here, a temperature-controlled column-stripping method was employed to determine Henry's Law coefficients for these compounds over the temperature range 281–302 K. Coefficients were derived from regression fits to the observed rates of losses from the liquid phase as a function of column depth in order to explicitly take account of potential non-attainment of equilibrium between liquid and gas phases. Temperature dependent expressions summarising the Henry's Law coefficients of phenol, o-cresol and 2-Nitrophenol over the stated temperature range are ln H( M atm −1 )=5850/T−11.6 , ln H( M atm −1 )=6680/T−15.4 and ln H( M atm −1 )=6270/T−16.6 , respectively (to within 15% of all measured values in this work). A thorough comparison with the previous literature-published values has been undertaken.
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Mass Accommodation Coefficients of Phenol, 2-Nitrophenol, and 3-Methylphenol over the Temperature Range 278−298 K
The Journal of Physical Chemistry A, 2002Co-Authors: B. Müller, Mathew R. HealAbstract:The reactive uptake of phenol, 2-Nitrophenol, and 3-methylphenol (m-cresol) was measured in a vertical wetted-wall flow reactor over the temperature range 278−298 K using bromine as an aqueous phase scavenger. First-order decays in gas-phase concentration as a function of increased gas−liquid contact time in the reactor were monitored by UV absorption downstream of the contact zone. Mass accommodation coefficients, α, were derived from measured uptake coefficients by correcting for limitations to mass transfer from radial gas-phase diffusion. Temperature-dependent expressions fitted to the data yielded values of α that decrease from 3.7 × 10-2 to 6.6 × 10-3 for phenol, 1.5 × 10-2 to 1.1 × 10-3 for 2-Nitrophenol, and 1.0 × 10-2 to 5.1 × 10-3 for m-cresol over the range 278 K to 298 K. (Estimated overall uncertainty in α values of ∼±30%). These are the first published accommodation data for the latter two aromatic species. The thermodynamic data derived from the values of α were interpreted in terms of the ...
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The Henry's law coefficient of 2-Nitrophenol over the temperature range 278-303 K.
Chemosphere, 2001Co-Authors: B. Müller, Mathew R. HealAbstract:Although 2-Nitrophenol has been identified as an important environmental chemical there is scarcity in the literature regarding the temperature dependence of its Henry's law coefficient, H. Here a bubble purge method was used to measure H for 2-Nitrophenol over the temperature range 278–303 K. A novel approach in the data treatment allowed correction of the data for non-equilibrium partitioning in the apparatus to obtain the true equilibrium H value. The experimentally derived temperature-dependent expression for H of 2-Nitrophenol is lnH(Matm−1)=(6290/T(K))−16.6. The standard enthalpy and entropy of gas-to-liquid transfer for 2-Nitrophenol in aqueous solution are −52.3±8.1kJmol−1 and −138±28Jmol−1K−1, respectively. (Errors are 95% confidence intervals.)
Paolo Fornasiero - One of the best experts on this subject based on the ideXlab platform.
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sunlight induced formation of surface bi2o4 x bi2o3 nanocomposite during the photocatalytic mineralization of 2 chloro and 2 Nitrophenol
Applied Catalysis B-environmental, 2015Co-Authors: Abdul Hameed, Muhammad Aslam, Iqbal M.i. Ismail, Numan Salah, Paolo FornasieroAbstract:Abstract The photocatalytic mineralization of 2-chlorophenol (2-CP) and 2-Nitrophenol (2-NP) was investigated using α-Bi 2 O 3 . The experiments were performed both in complete spectrum and in the visible region (420–800 nm) of the sunlight. The materials were fully characterized by means of UV–vis diffuse reflectance spectroscopy (DRS), photoluminescence (PL), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) analysis and field emission scanning electron microscopy (FESEM). α-Bi 2 O 3 showed considerably higher activity for the mineralization of 2-Nitrophenol and 2-chlorophenol under natural sunlight exposure, however still appreciable activity was observed in the visible region. Formation of surface nanocomposites Bi 2 O 4− x –Bi 2 O 3 was observed under sunlight irradiation due to the presence of UV light. The sunlight exposed Bi 2 O 3 , i.e. Bi 2 O 4− x –Bi 2 O 3 composite, showed excellent activity for the degradation and mineralization of 2-CP and 2-NP in the visible region of sunlight. A key role of both hydroxyl and superoxide anion radicals was evidenced in the degradation and mineralization processes under sunlight while only hydroxyl radicals were identified as major facilitators under visible light irradiation.
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Sunlight induced formation of surface Bi2O4−x–Bi2O3 nanocomposite during the photocatalytic mineralization of 2-chloro and 2-Nitrophenol
Applied Catalysis B: Environmental, 2015Co-Authors: Abdul Hameed, Muhammad Aslam, Iqbal M.i. Ismail, Numan Salah, Paolo FornasieroAbstract:Abstract The photocatalytic mineralization of 2-chlorophenol (2-CP) and 2-Nitrophenol (2-NP) was investigated using α-Bi 2 O 3 . The experiments were performed both in complete spectrum and in the visible region (420–800 nm) of the sunlight. The materials were fully characterized by means of UV–vis diffuse reflectance spectroscopy (DRS), photoluminescence (PL), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) analysis and field emission scanning electron microscopy (FESEM). α-Bi 2 O 3 showed considerably higher activity for the mineralization of 2-Nitrophenol and 2-chlorophenol under natural sunlight exposure, however still appreciable activity was observed in the visible region. Formation of surface nanocomposites Bi 2 O 4− x –Bi 2 O 3 was observed under sunlight irradiation due to the presence of UV light. The sunlight exposed Bi 2 O 3 , i.e. Bi 2 O 4− x –Bi 2 O 3 composite, showed excellent activity for the degradation and mineralization of 2-CP and 2-NP in the visible region of sunlight. A key role of both hydroxyl and superoxide anion radicals was evidenced in the degradation and mineralization processes under sunlight while only hydroxyl radicals were identified as major facilitators under visible light irradiation.
Abdul Hameed - One of the best experts on this subject based on the ideXlab platform.
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sunlight induced formation of surface bi2o4 x bi2o3 nanocomposite during the photocatalytic mineralization of 2 chloro and 2 Nitrophenol
Applied Catalysis B-environmental, 2015Co-Authors: Abdul Hameed, Muhammad Aslam, Iqbal M.i. Ismail, Numan Salah, Paolo FornasieroAbstract:Abstract The photocatalytic mineralization of 2-chlorophenol (2-CP) and 2-Nitrophenol (2-NP) was investigated using α-Bi 2 O 3 . The experiments were performed both in complete spectrum and in the visible region (420–800 nm) of the sunlight. The materials were fully characterized by means of UV–vis diffuse reflectance spectroscopy (DRS), photoluminescence (PL), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) analysis and field emission scanning electron microscopy (FESEM). α-Bi 2 O 3 showed considerably higher activity for the mineralization of 2-Nitrophenol and 2-chlorophenol under natural sunlight exposure, however still appreciable activity was observed in the visible region. Formation of surface nanocomposites Bi 2 O 4− x –Bi 2 O 3 was observed under sunlight irradiation due to the presence of UV light. The sunlight exposed Bi 2 O 3 , i.e. Bi 2 O 4− x –Bi 2 O 3 composite, showed excellent activity for the degradation and mineralization of 2-CP and 2-NP in the visible region of sunlight. A key role of both hydroxyl and superoxide anion radicals was evidenced in the degradation and mineralization processes under sunlight while only hydroxyl radicals were identified as major facilitators under visible light irradiation.
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Sunlight induced formation of surface Bi2O4−x–Bi2O3 nanocomposite during the photocatalytic mineralization of 2-chloro and 2-Nitrophenol
Applied Catalysis B: Environmental, 2015Co-Authors: Abdul Hameed, Muhammad Aslam, Iqbal M.i. Ismail, Numan Salah, Paolo FornasieroAbstract:Abstract The photocatalytic mineralization of 2-chlorophenol (2-CP) and 2-Nitrophenol (2-NP) was investigated using α-Bi 2 O 3 . The experiments were performed both in complete spectrum and in the visible region (420–800 nm) of the sunlight. The materials were fully characterized by means of UV–vis diffuse reflectance spectroscopy (DRS), photoluminescence (PL), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) analysis and field emission scanning electron microscopy (FESEM). α-Bi 2 O 3 showed considerably higher activity for the mineralization of 2-Nitrophenol and 2-chlorophenol under natural sunlight exposure, however still appreciable activity was observed in the visible region. Formation of surface nanocomposites Bi 2 O 4− x –Bi 2 O 3 was observed under sunlight irradiation due to the presence of UV light. The sunlight exposed Bi 2 O 3 , i.e. Bi 2 O 4− x –Bi 2 O 3 composite, showed excellent activity for the degradation and mineralization of 2-CP and 2-NP in the visible region of sunlight. A key role of both hydroxyl and superoxide anion radicals was evidenced in the degradation and mineralization processes under sunlight while only hydroxyl radicals were identified as major facilitators under visible light irradiation.