TY  - JOUR
A1  - Omorogie, Martins O.
A1  - Babalola, Jonathan Oyebamiji
A1  - Unuabonah, Emmanuel I.
A1  - Song, Weiguo
A1  - Gong, Jian Ru
T1  - Efficient chromium abstraction from aqueous solution using a low-cost biosorbent: Nauclea diderrichii seed biomass waste
JF  - Journal of Saudi Chemical Society
N2  - Toxic Cr(III) which poses environmental hazard to flora and fauna was efficiently abstracted by low-cost Nauclea diderrichii seed biomass (NDS) with good sequestral capacity for this metal was investigated in this study. The NDS surface analyses showed that it has a specific surface area of 5.36 m(2)/g and pHpzc of 4.90. Thermogravimetric analysis of NDS showed three consecutive weight losses from 50-200 degrees C (ca. 5%), 200-400 C (ca. 35%), >400 degrees C (ca. 10%), corresponding to external water molecules, structural water molecules and heat induced condensation reactions respectively. Differential thermogram of NDS presented a large endothermic peak between 20-510 degrees C suggesting bond breakage and dissociation with the ultimate release of small molecules. The experimental data showed kinetically fast biosorption with increased initial Cr(III) concentrations, indicating the role of external mass transfer mechanism as the rate controlling mechanism in this adsorption process. The Langmuir biosorption capacity of NDS was 483.81 mg/g. The use of the corrected Akaike Information Criterion tool for ranking equilibrium models suggested that the Freundlich model best described the experimental data, which is an indication of the heterogeneous nature of the active sites on the surface of NDS. N. diderrichii seed biomass is an easily sourced, cheap and environmental friendly biosorbent which will serve as a good and cost effective alternative to activated carbon for the treatment of polluted water and industrial effluents. (C) 2012 King Saud University. Production and hosting by Elsevier B.V. All rights reserved.
KW  - Biomass
KW  - Equilibrium
KW  - External mass transfer
KW  - Kinetics
KW  - Adsorption
KW  - Water
Y1  - 2016
U6  - https://doi.org/10.1016/j.jscs.2012.09.017
SN  - 1319-6103
SN  - 2212-4640
VL  - 20
SP  - 49
EP  - 57
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Vaz da Cruz, Vinicius
A1  - Büchner, Robby
A1  - Fondell, Mattis
A1  - Pietzsch, Annette
A1  - Eckert, Sebastian
A1  - Föhlisch, Alexander
T1  - Targeting individual tautomers in equilibrium by resonant inelastic X-ray scattering
JF  - The journal of physical chemistry letters
N2  - Tautomerism is one of the most important forms of isomerism, owing to the facile interconversion between species and the large differences in chemical properties introduced by the proton transfer connecting the tautomers. Spectroscopic techniques are often used for the characterization of tautomers. In this context, separating the overlapping spectral response of coexisting tautomers is a long-standing challenge in chemistry. Here, we demonstrate that by using resonant inelastic X-ray scattering tuned to the core excited states at the site of proton exchange between tautomers one is able to experimentally disentangle the manifold of valence excited states of each tautomer in a mixture. The technique is applied to the prototypical keto-enol equilibrium of 3-hydroxypyridine in aqueous solution. We detect transitions from the occupied orbitals into the LUMO for each tautomer in solution, which report on intrinsic and hydrogen-bond-induced orbital polarization within the pi and sigma manifolds at the proton-transfer site.
KW  - Equilibrium
KW  - Molecular structure
KW  - Molecules
KW  - Nitrogen
KW  - Solvents
Y1  - 2022
U6  - https://doi.org/10.1021/acs.jpclett.1c03453
SN  - 1948-7185
VL  - 13
IS  - 10
SP  - 2459
EP  - 2466
PB  - American Chemical Society
CY  - Washington
ER  -