Membranas de poliétersulfona/argila e sua permeabilidade à água

Cavalho, Thamyres Cardoso de; Medeiros, Vanessa da Nobréga; Leite, Amanda Melissa Damião; Araújo, Edcleide Maria; Lira, Hélio Lucena

doi:10.1590/s1517-707620170002.0157

Cited by 2 publications

(4 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In general, the membranes with the addition of clay, regardless of the added salt, showed lower contact angles, which corresponds to a higher hydrophilicity compared to the pure PA6 membrane. In this way, it was possible to verify that the presence of clay influenced the increase of the contact angle and is directly proportional to the increase in the percentage of clay [57][58][59].…”

Section: Diffusion Foundations Vol 14 93mentioning

confidence: 99%

Section: Diffusion Foundations Vol 14mentioning

confidence: 99%

“…Swelling is intrinsically related to the type of material that has hydrophilic characteristics, making easier the absorption of water and reducing the size of the pores on the surface of these membranes. In addition, swelling may directly contribute to the reduction of permeate flow[30,49,50,54,59,[62][63][64][65][66].The membrane prepared with CaCl 2 salt was chosen to perform the flow measurements of the oily emulsion because it showed higher permeate flow and a morphological structure more suitable for use in microfiltration, when compared to the flow and microstructure of the membranes with KCl. Figure23shows the flow measurement tests of oily emulsions at 1 and 2 bar pressures for the PA6 membrane and its hybrids with 1, 3 and 5% clay by adding the inorganic CaCl 2 salt.The flow measurements of the oil-in-water emulsions shown in Figure23(a) and (b) for the hybrid membranes were larger than the PA6 membrane flow, regardless of the pressure used,…”

mentioning

confidence: 99%

See 2 more Smart Citations

Influence of Additives on Hybrids Membranes Morphology for Water Treatment

Filho

Salviano

Araújo

et al. 2017

View full text Add to dashboard Cite

In this work, polyamide 6 membranes (PA6) and hybrids with 1, 3 and 5% of montmorillonite clay (MMT) were obtained, adding potassium chloride (KCl) and calcium chloride (CaCl2). These different additives are intended to promote formation and increase of the pores in the microporous membranes. The membranes in the form of thin films were prepared by the phase inversion technique, leading to flat selective barriers. The MMT clay was characterized by X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR). The membranes were characterized by XRD, FTIR, scanning electron microscopy (SEM), contact angle, water vapor permeation, flow measurements and yield. The clay XRD results showed characteristic peaks of bentonite containing accessory materials, as well as a peak at 5.93°, indicating the d001basal interplanar distance of 14.95 Å of MMT. In the spectrum in the infrared region of the clay, it was observed the presence of hydroxyls inherent to the adsorbed water, as well as characteristic bands of Si-O-Si bonds and the octahedral layer of MMT. The viscosities of the solutions of PA6 and their hybrids with CaCl2were higher compared to solutions containing KCl due the CaCl2possess a bivalent ion with a high degree of hydration and a molecular mass higher than KCl. In addition, these salts promote formation of hydroxides that precipitate the particles of MMT, decreasing the viscosities with the increasing percentage of clay. By means of the X-ray diffraction, it was possible to perceive that the hybrid membranes with the inorganic salts suggest an exfoliated and/or partially exfoliated structure. From the results of the FTIR analysis the bands obtained in the PA6 membranes and its hybrids remained practically unchanged, as there was an increase in the clay content and the introduction of the inorganic salts. From the photomicrographs obtained by SEM, it was observed that the addition of clay in the hybrid membranes provided an increase in the number of pores with the gradual increase of the percentage of clay. While the addition of the inorganic salts (KCl and CaCl2) provided an increase in the pore size of the top surfaces of all membranes, by means of the contact angle, it was verified that the hybrid membranes presented smaller angles when compared to the PA6, probably, due to the superficial peculiarity of the clay to react with water. PA6 membranes with KCl and CaCl2showed lower water vapor permeations as compared to hybrid membranes due to the increase in the size and quantity of pores presented on their top surfaces. The distilled water flow in the membranes initially showed a decrease and after 30 minutes a stability of the permeate flow due to a compression occurred in the membranes. The water-oil separation tests of the membranes with CaCl2, regardless of the pressure used, indicated a significant reduction of permeate oil with promising yields above 87% , presenting potential for the treatment of wastewater contaminated by oil.

show abstract

Section: Diffusion Foundations Vol 14 93mentioning

confidence: 99%

Section: Diffusion Foundations Vol 14mentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Influence of Additives on Hybrids Membranes Morphology for Water Treatment

Filho

Salviano

Araújo

et al. 2017

View full text Add to dashboard Cite

show abstract

“…Carvalho [22] obteve membranas de poliétersulfona (PES) e poliétersulfona/argila pela técnica de inversão de fase e avaliar a presença de argila na obtenção de membranas para o tratamento de efluentes líquidos. O solvente utilizado foi a dimetilformamida (DMF) e argilas utilizadas foram Brasgel PA (MMT) e Cloisite Na (CL Na) nas proporções de 3 a 5% (em peso).…”

Section: Introductionunclassified

Membranas de fibra oca de polietersulfona: efeito do líquido interno e da adição de argila

et al. 2019

Self Cite

View full text Add to dashboard Cite

RESUMO As membranas poliméricas vêm sendo bastante utilizadas no processo de tratamento de efluentes em todo mundo, solucionando problemas médicos, sociais e ambientais. Sendo assim, membranas de fibra oca foram produzidas a partir da polietersulfona (PES), adicionando a argila Cloisite Na – CLNa e também inserindo o solvente N,N dimetilformamida (DMF), com o intuito de modificar a morfologia da membrana. A argila foi caracterizada por fluorescência de raios-X (FRX) e difração de raios-X (DRX). Por FRX, ficou visto que a argila apresentou característica naturalmente sódica e com pouco materiais acessórios. O DRX mostrou que a Cloisite Na possui característica de uma argila montmorilonita contendo íons Na+. As membranas foram caracterizadas por ângulo de contato (membrana plana), microscopia eletrônica de varredura (MEV) e medidas de fluxo. Por meio das medidas do ângulo de contato foi visto que a presença de argila favoreceu a um aumento da hidrofilicidade das membranas. Nas membranas de fibra oca, foi observado por MEV que a presença da argila modificou a morfologia da membrana, alterando a uniformidade dos “fingers” e dos macroporos e modificando a camada densa no centro do suporte poroso, A adição do ácido no líquido interno modificou ainda mais a morfologia, diminuindo a camada densa no centro do suporte poroso da membrana e também alterando os “fingers” e os macroporos, tendo uma maior uniformidade dos mesmos em relação a membrana sem a presença do DMF no líquido interno. A partir das medidas de fluxo foi possível observar que a membrana contendo 5% de CLNa com a presença do solvente no líquido interno obteve um maior fluxo com o tempo, isto ocorreu devido à morfologia mais uniforme apresentada da membrana.

show abstract

Membranas de poliétersulfona/argila e sua permeabilidade à água

Cited by 2 publications

References 25 publications

Influence of Additives on Hybrids Membranes Morphology for Water Treatment

Influence of Additives on Hybrids Membranes Morphology for Water Treatment

Membranas de fibra oca de polietersulfona: efeito do líquido interno e da adição de argila

Contact Info

Product

Resources

About