RT Journal Article
T1 Chemical reduction of nitrate by zero-valent iron: Shrinking-Core versus Surface Kinetics Models
A1 Villén-Guzmán, María Dolores
A1 Paz-García, Juan Manuel
A1 Arhoun, Brahim
A1 Cerrillo-González, María del Mar
A1 Rodríguez-Maroto, José Miguel
A1 Vereda-Alonso, Carlos
A1 Gómez-Lahoz, César
K1 Membranas intercambiadoras de iones
K1 Intercambio iónico
AB Zero valent iron (ZVI) is being used in permeable reactive barriers (PRB) for the removal of oxidant contaminants, from nitrate to chlorinated organics. A sound design of these barriers requires a good understanding of kinetics. Here we present a study of the kinetics of nitrate reduction under relatively low values of pH, from 2 to 4.5. We use a particle size of 0.42 mm, which is within the recommended size for PRBs (0.2 mm to 2.0 mm). In order to avoid possible mass-transfer limitations, a well-stirred reactor coupled with a fluidized bed reactor was used. The experiments were performed at constant pH values using a pH controller that allows to accurately track the amount of acid added. Since the reduction of H+ to H2 by the oxidation of ZVI will always be present for these pH values, blank experiments (without nitrate) were performed and the rate of this H+ reduction obtained. This rate of reduction was studied using three kinetic models: a regular empirical one, the Shrinking-Core Model (SCM), and the Surface Kinetics Model (SKM). The best performance was obtained from the SKM model. Therefore, this model was also used to study the results for the nitrate reduction, also with satisfactory results. In both cases, some assumptions are introduced to maintain a moderate number of fitting parameters.
PB MDPI
YR 2020
FD 2020-02-12
LK https://hdl.handle.net/10630/20678
UL https://hdl.handle.net/10630/20678
LA eng
NO Villen-Guzman, M.; Paz-Garcia, J.M.; Arhoun, B.; Cerrillo-Gonzalez, M.d.M.; Rodriguez-Maroto, J.M.; Vereda-Alonso, C.; Gomez-Lahoz, C. Chemical Reduction of Nitrate by Zero-Valent Iron: Shrinking-Core versus Surface Kinetics Models. Int. J. Environ. Res. Public Health 2020, 17, 1241.
NO This research was funded by the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement No. 778045, by the “Proyectos I + D + i en el marco del Programa Operativo FEDER Andalucía 2014–2020, No UMA18-FEDERJA-279” and the project from the University of Malaga, No. PPIT.UMA.B5.2018/17. Villen-Guzman acknowledges the postdoctoral fellowship obtained from the University of Malaga. Cerrillo-Gonzalez acknowledges the FPU grant obtained from the Spanish Ministry of Education.
DS RIUMA. Repositorio Institucional de la Universidad de Málaga
RD 22 ene 2026