Arsenic adsorption and desorption on syntetic iron oxyhydroxides as study model to explain one of the mechanisms for its lixiviation from mining tailings

 

A. de la Peña-Torres, I. Cano-Rodríguez, A.F. Aguilera-Alvarado, Z. Gamiño-Arroyo, F.I. Gómez-Castro, M.P. Gutiérrez-Valtierra and S. Soriano-Pérez

 

 

  • The adsorption of arsenic on synthetic goethite and ferrihydrite is determined by pseudo-first order kinetics, and arsenic can be quickly desorbed by effect of bicarbonate solutions.

  • The process of arsenic adsorption-desorption on synthetic oxyhydrates did not show temperature dependency.

  • In the mining tailings under study there is a fraction of arsenic bound to oxyhydrates that could be lixiviated by bicarbonate solutions; this fraction (25% of the total) is susceptible of lixiviation that could be incorporated quickly into aqueous systems, as explained by the proposed model.