The Experts below are selected from a list of 66 Experts worldwide ranked by ideXlab platform
B E Conway - One of the best experts on this subject based on the ideXlab platform.
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Adsorption of Organics onto an high area c cloth electrode from organic solvents and organic solvent water mixtures
Journal of Electroanalytical Chemistry, 2003Co-Authors: Jianjun Niu, B E ConwayAbstract:The application of high-area C-cloth electrodes as effective adsorbent materials in organic solvents and in aqueous/organic solvent mixtures was studied using aniline and pyridine as model adsorbate solutes. These were selected in relation to understanding the Adsorption and electrosorption behaviours of organic pollutants in such aqueous/non-aqueous mixtures and to development of methodology for clean-up of organic solvents or industrial waste-waters. The Adsorption/electrosorption processes were followed by in situ UV-spectroscopy which also provided dynamical data for easy kinetic analysis. Large differences in the (apparent) double-layer capacity of the C-cloth observed in ethanol (EtOH), n-propanol, and acetonitrile (MeCN), in relation to that in water, suggest the significance of differences of solution conductivity determining the distributed electrolytic resistance in the pores of the C matrix, as in the model of de Levie. Adsorption of both aniline and pyridine was found to be significantly promoted by either galvanostatic or potentiostatic polarization of the C-cloth electrode, as previously found for aqueous solutions. Introduction of organic solvents into aqueous solution was shown to have strong positive or negative effects on the electrosorption processes depending on the respective solvents and adsorbates used, and the role of hydrophobic effects in Adsorption from aqueous media. A common enhancement of extents of Adsorption of both aniline and pyridine in each of the organic solvents investigated was also found by measurements of Adsorption on open-circuit followed by electrosorption upon polarization.
Krishna Muralidharan - One of the best experts on this subject based on the ideXlab platform.
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A computational investigation of Adsorption of Organics on mineral surfaces: Implications for Organics delivery in the early solar system
Earth and Planetary Science Letters, 2014Co-Authors: Abu Md. Asaduzzaman, Thomas J. Zega, Slimane Laref, Keith Runge, Pierre A Deymier, Krishna MuralidharanAbstract:Abstract The Adsorption of simple organic compounds onto minerals that are known to occur in the early solar nebula such as olivine, spinel and water-ice, is examined using first-principles density functional theory. The calculations show that electron-rich Organics and Organics containing cyanide, amine and carboxylic functional groups can strongly bind to low-index surfaces of olivine and spinel. Based on the surface coverage as obtained from these calculations, it can be inferred that an estimated amount of 10 13 kg of Organics could have been delivered to early Earth via direct Adsorption mechanisms, thereby providing an endogenous source of planetary Organics. In addition, Adsorption of organic compounds on magnesite, a carbonate phase believed to have formed via aqueous processes on asteroidal bodies, is also studied. The Adsorption behavior of the Organics is observed to be similar in both cases, i.e., for minerals that formed during the earliest stages of nebular evolution through condensation (spinel and olivine) or other processes and for those that formed via hydration processes on asteroidal bodies (magnesite). These results suggest that direct incorporation via Adsorption is an important delivery mechanism of Organics to both asteroidal bodies and terrestrial planets.
S Biniak - One of the best experts on this subject based on the ideXlab platform.
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Adsorption equilibria in the systems aqueous solutions of Organics oxidized activated carbon samples obtained from different parts of granules
Fuel, 2006Co-Authors: Anna Derylomarczewska, A Swiatkowski, Bronislaw Buczek, S BiniakAbstract:Abstract The Adsorption of Organics from aqueous solutions on the oxidized activated carbon samples obtained by gradual abrasion of granules is studied. The low temperature nitrogen Adsorption–desorption isotherms are applied to determine the parameters of porous structure of investigated materials. The chemistry of adsorbent surface is characterized using XPS technique and Boehm titration method. The Adsorption isotherms of three organic substances from dilute aqueous solutions are also measured. The influence of changes of surface properties inside of a carbon particle on organic solute Adsorption from aqueous solutions is analyzed and discussed.
Jianjun Niu - One of the best experts on this subject based on the ideXlab platform.
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Adsorption of Organics onto an high area c cloth electrode from organic solvents and organic solvent water mixtures
Journal of Electroanalytical Chemistry, 2003Co-Authors: Jianjun Niu, B E ConwayAbstract:The application of high-area C-cloth electrodes as effective adsorbent materials in organic solvents and in aqueous/organic solvent mixtures was studied using aniline and pyridine as model adsorbate solutes. These were selected in relation to understanding the Adsorption and electrosorption behaviours of organic pollutants in such aqueous/non-aqueous mixtures and to development of methodology for clean-up of organic solvents or industrial waste-waters. The Adsorption/electrosorption processes were followed by in situ UV-spectroscopy which also provided dynamical data for easy kinetic analysis. Large differences in the (apparent) double-layer capacity of the C-cloth observed in ethanol (EtOH), n-propanol, and acetonitrile (MeCN), in relation to that in water, suggest the significance of differences of solution conductivity determining the distributed electrolytic resistance in the pores of the C matrix, as in the model of de Levie. Adsorption of both aniline and pyridine was found to be significantly promoted by either galvanostatic or potentiostatic polarization of the C-cloth electrode, as previously found for aqueous solutions. Introduction of organic solvents into aqueous solution was shown to have strong positive or negative effects on the electrosorption processes depending on the respective solvents and adsorbates used, and the role of hydrophobic effects in Adsorption from aqueous media. A common enhancement of extents of Adsorption of both aniline and pyridine in each of the organic solvents investigated was also found by measurements of Adsorption on open-circuit followed by electrosorption upon polarization.
Artur P Terzyk - One of the best experts on this subject based on the ideXlab platform.
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molecular properties and intermolecular forces factors balancing the effect of carbon surface chemistry in Adsorption of Organics from dilute aqueous solutions
Journal of Colloid and Interface Science, 2004Co-Authors: Artur P TerzykAbstract:Presented paper recapitulates the results of 6 years' study concerning the effect of carbon surface chemical composition on Adsorption of paracetamol, phenol, acetanilide, and aniline from dilute aqueous solutions on carbons. Adsorption-desorption isotherms, enthalpy, and kinetics of Adsorption data are shown for the measurements performed at three temperatures (300, 310, and 320 K) at two pH levels (1.5 and 7) on commercial activated carbons. The data were obtained for four carbons: the initial carbon D43/1 and forms modified by applying concentrated HNO3, fuming H2SO4, and gaseous NH3. The modification procedures do not change the porosity in a drastic way, but lead to drastic changes of the composition of carbon surface layer. By applying MOPAC (a general-purpose semiempirical molecular orbital package), the physicochemical constants characterizing the molecules of adsorbates are calculated, including the distribution of the Mulliken charges, the dipole moments and ionization potentials, and the energies of interaction with the unique positive and negative charges. They are correlated with the parameters characterizing the Adsorption (and kinetics) process of studied molecules on the mentioned above carbons. The mechanisms proposed in the literature for the description of Adsorption from dilute aqueous solutions are verified, and a general mechanism of Adsorption is proposed.
