Condensation of WO42- Polyhedra Units on Layered Rare Earth Hydroxides Nanosheets: Hierarchical Channels and Heavy Metal Adsorption


Condensation of WO42- Polyhedra Units on Layered Rare Earth Hydroxides Nanosheets: Hierarchical Channels and Heavy Metal Adsorption

Solomon Omwoma

Porous materials exhibit advantages in adsorption applications due to their ability to increase accessibility, surface area and enhanced liquid/molecular/ion transport. Condensation of WO42- polyhedra units on delaminated europium containing layered rare earth hydroxide nanosheets, [Eu8(OH)20(H2O)n]4+, at pH 5 under nitrogen environment is herein reported to form a porous material with hierarchical channels characterized as Eu2(OH)5[H2W12O40]0.17∙7H2O. Heavy metal adsorption by this material was found to be 1.8, 2.4 and 4.1mmol/g for Cd2+, Pb2+ and Cr6+ within contact times of 18, 25 and 20 minutes respectively. The sorption mechanism was pseudo-second order and obeyed the Langmuir sorption model.

Metal-Organic Frameworks, Layered Rare Earth Hydroxides, Heavy Metals, Adsorption

Published online 6/30/2019, 18 pages

Citation: Solomon Omwoma, Condensation of WO42- Polyhedra Units on Layered Rare Earth Hydroxides Nanosheets: Hierarchical Channels and Heavy Metal Adsorption, Materials Research Foundations, Vol. 53, pp 122-139, 2019


Part of the book on Metal-Organic Framework Composites

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