Enhancing Chromium (VI) removal from synthetic and real tannery effluents by using diatomite-embedded nanopyroxene
Date
2020-03-18
Authors
Hethnawi, Afif
Khderat, Wisal
Hashlamoun, Kotaybah
Kanan, Amer
Nassar, Nashaat N.
Journal Title
Journal ISSN
Volume Title
Publisher
Elsevier
Abstract
A commercial filter aid material of Diatomite was modified via loading it with a low mass fraction of
polyethylenimine-functionalized pyroxene nanoparticles (PEI-PNs) to enhance its adsorption activities.
The modified Diatomite was then used for Cr(VI) removal from dichromate solution and from real
tannery wastewater. For the synthetic wastewater, batch adsorption experiments were first performed at
various pH and Cr(VI) initial concentrations. Then, the obtained kinetic parameters were used to
investigate the continuous adsorption inside the fixed-bed column. The continuous removal of the Cr(VI)
was performed inside a fixed-bed column under various influent flow rates, Cr(VI) initial concentrations,
and bed-heights. In the column experiments, high adsorption of Cr(VI) was observed at low flow rates,
high bed heights, and low influent initial concentrations. A dimensionless form of the advection-axial
dispersion model, featuring Peclet number as a fitting parameter, was then used to study the breakthrough
behavior under various dynamic parameters. Afterward, the modified Diatomite was used to
remediate well characterized real tannery wastewater. For the treatment of the tannery wastewater, our
modified filter aid, compared with the non-modified one, showed an outstanding performance and a
higher removal efficiency.
Description
Keywords
Tannery wastewater , Chromium , Adsorption , Fixed-bed column , Dimensionless advection-axial dispersion , model