OLIVEIRA, S. S. L.; http://lattes.cnpq.br/9023139959148953; OLIVEIRA, Sandriely Sonaly Lima.
Resumo:
Hollow fiber ceramic membranes with an asymmetric structure can be used
as a support for membranes with smaller pore sizes, due to the resistance to
thermal shock, excellent chemical and mechanical stability. In this way, this work has
The objective is to develop and characterize membranes in the form of hollow fibers from
alumina, kaolin and the alumina/kaolin mixture, aimed at application in the separation of oil in
oil/water emulsion and indigo blue dispersed in water. Dispersions were prepared
with ceramic powders, polyethersulfone (PE S), 1-methyl-2-pyrrolidone (NMP) and
polyvinylpyrrolidone (PVP), and through the cold extrusion technique with precipitation by
immersion, and different sintering temperatures (1300-1500 ºC) were obtained
membranes with hollow fiber geometry. For the characterization of alumina and kaolin
analyzes were carried out: chemistry, X-ray diffraction (DR X) and particle size distribution. A
characterization of the membranes was carried out by analysis of: XRD, electron microscopy
scanning (ME V), mechanical resistance and apparent porosity. The main phases
crystalline substances present in kaolin were: kaolinite, quartz and mica. The DR X results
of the membranes showed the appearance and changes of the phases: alumina, quartz, and
mulita. The ME V images of the transverse section of the membrane showed that these are
asymmetrical porous, with sponge-like structures. The membranes with the highest
amount of alumina and/or kaolin showed greater flexural strength and lower
porosity for all temperatures analyzed, and the higher the temperature of
sintering reduces the flow. Regarding the oil separation processes in the form of
emulsion and indigo blue, the membranes obtained showed a yield above 90%,
with emphasis on the composition 56%A-30%C; the yield was higher than the values
reported in the literature, indicating better rejection of oil and indigo blue with the
system and the type of membrane prepared in this study. Using planning
experimentally, it was observed that the input variables for all membranes
showed similar behavior in terms of flow and yield, that is, the
increase in transmembrane pressure increased flow and reduced efficiency in
separation of the emulsified oil and indigo blue. Therefore, it was found that the addition of
kaolin to alumina provided an increase in the mechanical resistance of the membranes without
compromising flow properties and obtaining excellent yields, regardless of the
treated effluent, proving the importance of manufacturing composite membranes
hollow fiber, which aims to synergize the best properties of each raw material with
potential for application in microfiltration processes.
