Desenvolvimento de membranas cerâmicas para tratamento de efluentes.

Abstract

Membrane separation process are experience a considerably progress in recent years and has competed with classical separation techniques. The membranes in general are used in the most different activities and effluent treatment is one of the most important area of application. In this way, this work consists in obtaining tubular ceramic membranes by the extrusion process, starting from a mass composed by kaolin and ball clay and sintered at temperatures of 900, 1000 and 1100° C to be applied in the treatment of effluent from textile industry. The characterization of the mass was done before sintering by plasticity analysis, chemical analysis, particle size, thermic and x-ray diffraction. Chemical analysis showed high content of Si02 and AI2O3. The results from thermogravimetric analysis presented total weight loss of 13.8%, the particle analysis showed particles with diameters with 50% of the particles close to 3.52 urn, the test for x-ray diffraction registered the presence of quartz, kaolinite and mica. The characterization of the mass after the sintering by x-ray diffraction showed the presence of mullite for the mass sintered at 1000°C. For the membranes it was done the shrinkage analysis, scanning electron microscopy, porosimetry by mercury intrusion, turbidity and flow analysis. The results showed that the membranes presented shrinkage from 1.23 to 9.18%, porous morphology and surface free from fissures, pore size in the range of microfiltration and porosity between 25.16 and 40.38%. The largest water permeated flux with desalinated water and effluent from textile industry was achieved by membrane sintered at 1000°C. The membranes reduced considerably the turbidity of the industrial effluent, reaching rate of rejection of solid particles close to 100%.