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Guilherme Luiz Dotto – One of the best experts on this subject based on the ideXlab platform.
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.
Origin of the outstanding performance of ZnAl and MgFe layered double hydroxides in the adsorption of 2–Nitrophenol: A statistical physics assessmentJournal 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.
Adsorptive potential of Zn–Al and Mg–Fe layered double hydroxides for the removal of 2–Nitrophenol from aqueous solutionsJournal 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
Pankaj Kumar Arora – One of the best experts on this subject based on the ideXlab platform.
Diversity of 4-Chloro-2–Nitrophenol-Degrading Bacteria in a Waste Water SampleJournal 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.
Chemotaxis Away from 4-Chloro-2–Nitrophenol, 4-Nitrophenol, and 2,6-Dichloro-4-Nitrophenol by Bacillus subtilis PA-2Journal 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.
Biotransformation and chemotaxis of 4-chloro-2–Nitrophenol by Pseudomonas sp. JHNMicrobial 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.
Mathew R. Heal – One of the best experts on this subject based on the ideXlab platform.
Experimentally determined Henry’s Law coefficients of phenol, 2-methylphenol and 2–Nitrophenol in the temperature range 281–302 KAtmospheric 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.
Mass Accommodation Coefficients of Phenol, 2–Nitrophenol, and 3-Methylphenol over the Temperature Range 278−298 KThe 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 …
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.)