| Author(s) |
Patrícia Magalhães Pereira Silva, Andre Luiz Vilaça do Carmo, Roseanne Barata Holanda , Fernando Gama Gomes, Emanuela Pereira Nogueira, Adriano Lucheta, Raphael Vieira da Costa, Caio Cesar Amorim de Melo, Marcelo Montini |
| Abstract Scope |
Physical-chemical evaluation of Brazilian (Amazon region) bauxite residue (BR) and analysis of its acid neutralization capacity (ANC) using sulfuric acid (H2SO4), hydrochloric (HCl) and citric acid (C3H8O7) were carried out to assess the potential application of BR as soil ameliorant. Analysis indicated a particle size (D50) of 5.98-9.54 μm, 1.65g/cm3 density and 18.28 µS.cm-1 electrical conductivity. Minerals phase determined by XRD showed hematite, goethite aluminose, anatase, sodalite, gibbsite and quartz, in agreement with XRF (%) elemental characterization: Fe (34.0), Al (21.3), Si (16.8), Na (11.4), Ti (5.3), Ca (1.0), Zr (0.9), S (0,15), V (0,13) e Mn (0.1). ANC analysis conducted upon 21 days indicated a lower acid consumption and pH equilibrium for H2SO4 and HCl (1.35 and 1.00 mol H+/Kg, respectively and pH ̴ 8) comparing with C3H8O7 (2 mol H+/Kg and pH ̴ 9). Results validate and provide basis for an effective use of BR in agronomic applications. |