Electroadsorption of Bromide from Natural Water in Granular Activated Carbon
Metadatos
Mostrar el registro completo del ítemEditorial
MDPI
Materia
Electroadsortion Granular activated carbon Thrialomethanes Bromides
Fecha
2021Referencia bibliográfica
Ribes, D.; Morallón, E.; Cazorla-Amorós, D.; Osorio, F.; García-Ruiz, M.J. Electroadsorption of Bromide from Natural Water in Granular Activated Carbon. Water 2021, 13, 598. https://doi.org/ 10.3390/w13050598
Resumen
The adsorption and electroadsorption of bromide from natural water has been studied
in a filter-press electrochemical cell using a commercial granular activated carbon as the adsorbent.
During electroadsorption experiments, different voltages were applied (2 V, 3 V and 4 V) under
anodic conditions. The presence of the electric field improves the adsorption capacity of the activated
carbon. The decrease in bromide concentration observed at high potentials (3 V or 4 V) may be due
to the electrochemical transformation of bromide to Br2
. The anodic treatment produces a higher
decrease in the concentration of bromide in the case of cathodic electroadsorption. Moreover, in this
anodic electroadsorption, if the system is again put under open circuit conditions, no desorption of
the bromide is produced. In the case of anodic treatment in the following adsorption process after
24 h of treatment at 3 V, a new decrease in the bromide concentration is observed as a consequence
of the decrease in bromide concentration after the electrochemical stage. It can be concluded that
the electroadsorption process is effective against the elimination of bromide and total bromine in
water, with a content of 345 and 470 µg L−1
, respectively, reaching elimination values of 46% in a
single-stage electroadsorption process in bromide and total bromine. The application of the electric
field to the activated carbon with a positive polarization (anodic electroadsorption) increases the
adsorption capacity of the activated carbon significantly, achieving a reduction of up to 220 µg L−1
after 1 h of contact with water. The two stage process in which a previous electrochemical oxidation
is incorporated before the electroadsorption stage significantly increased the efficiency from 46% in a
single electroadsorption step at 3 V, to 59% in two stages.