Dissertação de Mestrado
Caracterização de espumantes com diferentes cadeias hidrocarbônicas e sua influência sobre a superfícideda hematita
Fecha
2012-08-27Autor
Vanessa Aparecida Alves de Paula Soares
Institución
Resumen
In mineral industry Mining industry normally looks for optimization of reagents related to flotation of iron ore, focusing on to achieve a more sustainable consumption, which leads to a new generation of reagents that, compared to the traditional ones, provides dosage reduction and an increased performance. The goal of this study was to characterize frothers with different hydrocarbon chains and to investigate their influence on the surface of hematite, using the frothers Flotanol M, Montanol 100 and Montanol 800, which were solubilized with the collector Flotigam EDA. Characterization of the hematite sample shows that it is actually a pure hematite. For the frothers, tests of gas chromatography, mass spectrometry and viscosity were performed, but only the frothers with simpler composition were confirmed (pentanol and hexanol); related to viscosity, it was noted that the more complex is the chemical composition the higher is the viscosity. The determination of hematite´s zeta potential was performed with the frothers Flotanol M, Montanol 100 and 800 in solution with the presence of Montanol Flotigam EDA in different concentrations. The hematite´s IEP found in the presence of Flotanol M at concentrations of 75 and 100 mg / L with addition of Flotigam EDA 10-4 M was at pH 6.7 and in concentration of 150 mg / L with addition of 10-4 M Flotigam EDA was at pH 3.4. The IEP measured for Montanol 100 was at pH 3.7 at concentrations of 75 and 100 mg / L and was at pH 3.3 at a concentration of 150mg / L with addition of Flotigam EDA 10-4 M. For all tests of the frother Montanol 800 the IEP was not found. Microflotation tests, performed in a modified Hallimond tube, determined the conditions of higher flotability of the hematite for the frothers Flotanol M, Montanol 100 and Montanol 800 in the presence of Flotigam EDA. The microflotation tests using Flotigam EDA 10-6 M together with Flotanol M or Montanol 800 were more effective in the concentration of hematite than using EDA Flotigam 10-6 M alone. Surface tension tests using Flotigam EDA in addition with the frothers Flotanol M, Montanol 100, Montanol 800 at different concentrations and using Flotigam EDA alone showed that the higher is the carbon chain and the more complex is the chemical composition of the frothers the lower is the surface tension. The results showed that the use of a frother with the Flotigam EDA, depending on the dosages, the type of flotation and the type of ore, can be extremely interesting in terms of cost/benefit and mass recovery.