title: Zeolitic tuffs for acid mine drainage (AMD) treatment in Ecuador: breakthrough curves for Mn2+, Cd2+, Cr3+, Zn2+, and Al3.
abstract: Zeolitic tuff constitutes a technical and economical feasible alternative to manage acidic waters in initial phases of generation. A study of cation exchange with two zeolitic tuffs from Ecuador and one from Cuba has been conducted using breakthrough curve methodology. Cations Mn2+, Cd2+, Cr3+, Zn2+, and Al3+have been chosen owing to their presence in underground water in exploration activities (decline development) in Fruta del Norte (Ecuador). Zeolites characterized by X-ray diffraction and thermal stability after heating overnight as heulandites show a similar exchange behavior for the five cations studied. The clinoptilolite sample Tasajeras shows a relevant cation exchange performance expressed in the important increment of spatial time to reach the breakthrough point in comparison with heulandite samples. The maximum length of unused beds was found for Cr3+and Zn2+cations showing, therefore, a lower adsorption performance in relation with Mn2+and Cd2+. A final disposal method of metal-loaded zeolites with cement is proposed.
authors.affiliation: Department of Energy and Fuels, ETS Ingenieros de Minas y Energia, Universidad Politécnica de Madrid, Ríos Rosas 21, 28003, Madrid, Spain.
authors.forename: Xavier
authors.initials: X
authors.lastname: Buenaño
authors.affiliation: Department of Energy and Fuels, ETS Ingenieros de Minas y Energia, Universidad Politécnica de Madrid, Ríos Rosas 21, 28003, Madrid, Spain. laureano.canoira.lopez@upm.es.
authors.forename: Laureano
authors.initials: L
authors.lastname: Canoira
authors.affiliation: Department of Mining and Geological Engineering, E.T.S. Ingenieros de Minas y Energía, Universidad Politécnica de Madrid, Ríos Rosas 21, 28003, Madrid, Spain.
authors.forename: Domingo
authors.initials: D
authors.lastname: Martin Sánchez
authors.affiliation: Department of Mining and Geological Engineering, E.T.S. Ingenieros de Minas y Energía, Universidad Politécnica de Madrid, Ríos Rosas 21, 28003, Madrid, Spain.
authors.forename: Jorge
authors.initials: J
authors.lastname: Costafreda
mesh_terms: D000327:Adsorption; D000535:Aluminum / Q000302:isolation & purification; D002104:Cadmium / Q000302:isolation & purification; D002857:Chromium / Q000302:isolation & purification; D003462:Cuba; D004484:Ecuador; D008345:Manganese / Q000302:isolation & purification; D008906:Mining; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods*; D017641:Zeolites / Q000737:chemistry*; D015032:Zinc / Q000302:isolation & purification*
chemical_list: D014874:Water Pollutants, Chemical; D002104:Cadmium; D002857:Chromium; D017641:Zeolites; D008345:Manganese; D000535:Aluminum; D015032:Zinc
keywords: Acidic mine waters; Cation exchange capacity; Cation saturation curves; Cement pozzolanic additives; Metal-loaded zeolites; Natural zeolites