1. Optimizing the selective precipitation of iron to produce yellow pigment from acid mine drainage
- Author
-
Marina Paula Secco, Ivo André Homrich Schneider, Rodrigo de Almeida Silva, Carlos Hoffmann Sampaio, Richard Thomas Lermen, Gelsa Edith Navarro Hidalgo, Universitat Politècnica de Catalunya. Departament d'Enginyeria Minera, Industrial i TIC, and Universitat Politècnica de Catalunya. GREMS - Grup de Recerca en Mineria Sostenible
- Subjects
Goethite ,Hematite ,02 engineering and technology ,010501 environmental sciences ,Raw material ,01 natural sciences ,Mineral industries--Environmental aspects ,020501 mining & metallurgy ,Pigment ,Acid mine drainage ,Selective precipitation ,0105 earth and related environmental sciences ,Precipitation (chemistry) ,Chemistry ,Mechanical Engineering ,General Chemistry ,Precipitació (Química) ,Geotechnical Engineering and Engineering Geology ,Pulp and paper industry ,Enginyeria civil::Enginyeria de mines [Àrees temàtiques de la UPC] ,Enginyeria química::Impacte ambiental [Àrees temàtiques de la UPC] ,0205 materials engineering ,Wastewater ,Precipitation (Chemistry) ,Control and Systems Engineering ,Reagent ,visual_art ,Indústria minera -- Aspectes ambientals ,Iron pigments ,visual_art.visual_art_medium ,sense organs - Abstract
Acid mine drainage (AMD) in the coal mining industry is recognized as one of the major sources of environmental damage. The active treatment of AMD involves adding alkaline reagents to wastewater so as to raise pH and to precipitate dissolved metals in the form of oxides/hydroxides. Studies have shown that yellow pigment (goethite) can be produced from the iron present in AMD. However, the presence of other metals can prevent the formation of pigment. Therefore, this paper seeks to evaluate several processes for purifying iron sludge so as to obtain raw material that can be recovered from AMD and thereby obtain a good quality of yellow pigment. The experiments were carried out by causing precipitation with strong and weak bases and removing other metals from the sludge by washing and filtering the sludge or by centrifugation. The results show that the color, type and morphology of the compounds changed, depending on the number of contaminants, and that these factors are strongly dependent on the type of reagent and less dependent on the separation process and the repetition of washes.
- Published
- 2019
- Full Text
- View/download PDF