TITLE:
Adsorption Kinetics of Matter Contained in a Leachate Using Eggshell and Activated Carbon
AUTHORS:
Erika Zamora-Villafranco, Icela D. Barceló-Quintal, Sergio Gomez-Salazar, Manuel Barceló-Quintal, Hugo E. Solís-Correa, Jesús Manuel Soriano-Rodríguez
KEYWORDS:
Adsorption, Activated Carbon, Eggshell, Kinetics, Leachate
JOURNAL NAME:
Journal of Environmental Protection,
Vol.5 No.7,
May
28,
2014
ABSTRACT: The generation
of highly polluting leachate from Sanitary Landfills has prompted the
development of technologies applicable to treatment of these liquids. The aim
of this study was to determine the kinetics of adsorption of organic and
inorganic matter contained in pre-treated leachate (by advanced oxidation by
the Fenton reaction); after two adsorbents were used, first eggshell and then activated
carbon. To determine the content of organic and inorganic matter COD was
measured; this was the parameter for monitoring the kinetics. The leachate was
subjected to advanced oxidation treatment by the Fenton reaction, then the
adsorption process was conducted by batch, in two consecutive steps, the first
step was the use of eggshell and the second step activated carbon. Due to the
oxidation treatment the pH value decreased to 2, after the adsorption eggshell
the pH increased to 6.9 and this was maintained in the treatment with activated
carbon. The kinetics of adsorption of organic and inorganic matter on eggshell
was evaluated by models pseudo-first-order and pseudo-second-order, the better
fitting was the latter. The adsorption process was adjusted to the model of
Langmuir. The negative value of △Hads indicated that the adsorption process was exothermic, spontaneous and
favorable. The separation factor RL of Langmuir Isotherm values indicated that the adsorption of the matter on the
eggshell was favorable at different temperatures. Finally, the activated carbon
adsorption of liquid obtained from treatment with eggshell was favored with the
kinetic model of pseudo second order. With the oxidation process, eggshell
adsorption and activated carbon adsorption, the removal COD was 98.6%. The
final COD value was fulfilled with the Mexican standard NOM-001-SEMARNAT-1996.