doctoralThesis
Flotabilidade de hematita e quartzo com amina e amido dosados em microemulsões e nanoemulsões
Fecha
2020-02-07Registro en:
NEITZKE, Paula Romyne de Morais Cavalcante. Flotabilidade de hematita e quartzo com amina e amido dosados em microemulsões e nanoemulsões. 2020. 160f. Tese (Doutorado em Engenharia Química) - Centro de Tecnologia, Universidade Federal do Rio Grande do Norte, Natal, 2020.
Autor
Neitzke, Paula Romyne de Morais Cavalcante
Resumen
The proper use of low-grade iron ore and its wastes is imperative to obtain a
reasonable development for sustainable industrial growth. Reverse cationic flotation is an
effective process when used in iron ore beneficiation. In this process, quartz, which is the
main gangue mineral, is floated with cationic collectors (amines). Starch is usually used in
iron oxide depression. Surfactant adsorption at the liquid / air and solid / liquid interfaces
plays an important role in many technological and industrial applications such as
emulsification, mineral flotation, and solid dispersion. In this work quartz and hematite
microflotation was performed using microemulsion and nanoemulsion systems.
Microemulsion and nanoemulsions systems were composed by: surfactant (Flotigam EDA
or Ultramine 150
), co-surfactant (n-butyl alcohol), oil phase (kerosene), and aqueous phase
or depressant solutions (Maizena
, soluble starch, amylose, or amidex). The influence of
operational parameters, such as concentration and type of surfactant, concentration and type
of depressant, and pH were evaluated. The results show that the performance of
nanoemulsions is superior to that of microemulsions, as well as the use of monoamine alkyl
ether solutions (conventional method). Maizena
, soluble starch, amidex, and amylose
depressants in nanoemulsified systems containing Flotigam EDA
, kerosene, and n-butyl
alcohol showed high floatability for quartz even at the highest concentrations of depressors
tested and were able to depress hematite, showing no evidence for clathrate formation.
Nanoemulsions with Ultramine 150
nonionic surfactant reached the maximum floatability
percentages for quartz (99.16%) and optimal hematite depression (89.10%). These results
show that the use of nanoemulsions in the reverse flotation process has potential application
in iron ore concentration, simplifying and leading to an improvement of the conventional
stepwise process.