Dionisio da Silva Biron

Preparation and Characterization of PA66/Alumina Composite Membrane

In this study, polymer/ceramic composite membranes were prepared and characterized. The polymer used was polyamide 66 (PA66) deposited by dip coating on the inner surface of α-alumina-based (Al2O3) microporous tube. A coating on the ceramic support surface and the formation of the selective layer was analyzed by scanning electron microscopy (SEM) in membranes with one (PA-1) and two layers (PA-2). The results of mercury porosimetry showed that the deposition of the polyamide layers decreases the average pore size. The PA-1 presented an average pore size of 0.35 μm, while the PA-2 presented two peaks of 0.18 and 0.56 μm. Both showed a superior performance than the ceramic support (pore diameter of 0.65 μm). Although, the permeate flux was higher with an impregnation membrane, the number of layers (one or two) just introduced a slight difference in pore statistical analysis. The order of rejection coefficient values for protein molecules is BSA > egg albumin > trypsin. The permeation tests showed that the composite membrane can be applied in ultrafiltration processes with MWCO of 69 kDa.

Characterization of Mullite Ceramic Membranes and their Application in the Removal Escherichia Coli

This paper aims the morphological and structural characterization of ceramic membranes of mullite and their application in the removal of Escherichia coli. A complex irregular structure presented by the pores of the membrane was verified by scanning electron microscopy (SEM). The average pore size and distribution were determined by mercury intrusion porosimetry. The average pore size of the material presented was 0,39 µm. Microfiltration tests resulted in a protein retention of 46, 76 and 89% for trypsin (TR), egg albumin (EA) and bovine serum albumin (BSA), proving the efficiency of the membrane microfiltration tests for molecular weight of 69 kDa. The application of the membranes on the retention of gram-negative bacterium E. coliresulted in a 66% efficiency at a pressure of 200 kPa and a 98% efficiency when applied a pressure of 50 kPa. Therefore, the use of mullite membranes show limited efficiency towards bacteria retention. Nevertheless, they present fluxes similar to other materials proposed in the literature.

Preparation and characterization of composite membranes ceramic/PSf and ceramic/PA 66

ABSTRACT In this paper, ceramic/polymer composite membranes have been prepared to evaluate the efficiency of polymer deposition on the ceramic support from to separation process of Ultrafiltration. Polymers used were polyamide 66 (PA 66) and polysulfone (PSf). The composite membranes were obtained immersing the supports into polymeric solutions to top layer formation. The presence of polymeric layer was observed on the surface of composite membranes by means of the Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM). Egg albumin (EA) solution was used to determine the rejection of the composite membranes. The ceramic support showed a higher flux value as expected, since its function is to favor flux passage. The composite membrane ceramic/PA 66 showed a higher flux than that of composite membrane ceramic/PSf. The EA rejection measured by reading the absorbance was 14, 42, and 62% to the support, composite membranes ceramic/PSf and ceramic/PA 66, respectively.

Applications of Ceramic Membranes

This chapter presents some of the possible applications shown by ceramic membranes. The following areas will be given emphasis:

Ceramic Membranes Characterization

This chapter is about some of the main methods used in the ceramic membranes characterization. Some of these methods are permeability, solute rejection assays, porosimetry by mercury intrusion, scanning electron microscopy, X-ray diffraction, among others.

Overview Membranes Separations

The technology of membranes separation is a field that involves many processes. These processes are subdivided according to the driving force applied, the feeding phases, the permeate, and the pores’ size.

Ceramic Membrane Modules

Membrane module can be understood as a physical unit, which gathers all the elements that participate in the separation process. Membrane module is, basically, composed by membranes, channels where feed goes through, the permeate and concentrate, and by pressure or current support structures applied to the system.

Ceramic Membranes Preparation

In this chapter emphasis will be given to the main raw materials used in production of ceramic membranes as well as with the main processes of obtaining the same. The need to understand the phenomena involved in the processing of ceramic membranes, as well as the interaction of materials used is of utter importance for the performance of the final product, in accordance with the type of process used.

Gas separation process: analysis of composite membranes based on alumina/PVDF at lower power consumption energy

Abstract Human activity have been emitting greenhouse gases into the atmosphere for a long time. To separate these gases, especially CO2 and CH4, polymeric membranes have been used in the chemical industry as this technology has a lower power consumption when compared to other separation processes. In this work, α-alumina ceramic tubes (support) were internally impregnated with poly(fluoride vinylidene) (PVDF), and the permeability and selectivity of the membrane to CO2, CH4, and O2 was studied. All membranes (MT1 and MT2), when tested at low pressures, presented higher selectivity to CH4 gas, and with increasing pressure the selectivity for CO2 increased as well. The MT2 membrane was more efficient in the separation of CO2/CH4 gases, which is an important result because both of them are the most impacting gases to the greenhouse effect and the most difficult to separate using membrane process.