Fabrication and study of fouling characteristics of HDPE/PEG grafted silica nanoparticles composite membrane for filtration of Humic acid

This research proposes to untangle the membrane fouling by introducing nanostructured magnetite (Fe3O4) colloids into the polymeric membrane. In present study, nanostructure magnetite nanoparticles (MNPs) were synthesized via co–precipitation method with ammonium hydroxide and sodium hydroxide as the precipitation agents at different pH condition. The synthesized MNPs were functionalized with poly(diallyldimethylammonium chloride) (PDDA) and then spin coated on the surface of the ultrafiltration cellulose acetate (CA) membrane. Intrinsic properties for this nano–composite membrane, in regards to the physical structures, surface negative charge density and the membrane filtration performance, on surface fouling by humic acid solutions were investigated. Experimental results demonstrated that, the nano–composite membrane has significantly reduced the humic acid fouling on the membrane surface. This could be explained by the electrostatic interactions between negatively charged humic acid molecules and the nano–composite membrane. Throughout the study, the results provide some fundamental insights into the physical interactions that governing the membrane fouling during filtration.

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Analysis of Fouling Characteristics of Diatomite Ceramic Membrane Using Filtration Models

E3S Web of Conferences ◽

10.1051/e3sconf/202123301049 ◽

2021 ◽

Vol 233 ◽

pp. 01049

Author(s):

YANG Yanqing ◽

QIU Yan ◽

LIU Yanhui ◽

ZHAO Yan ◽

LI jing ◽

...

Keyword(s):

Humic Acid ◽

Water Treatment ◽

Membrane Fouling ◽

Municipal Wastewater ◽

Ceramic Membrane ◽

Membrane Surface ◽

Drinking Water Treatment ◽

Polymeric Membrane ◽

Membrane Pore ◽

Fouling Characteristics

Ceramic membrane has made rapid progress in industrial/municipal wastewater treatment and drinking water treatment owing to its advantageous properties over conventional polymeric membrane. The ceramic membrane processes are a rapidly emerging technology for water treatment, yet virtually no information on the performance and fouling mechanisms diatomite ceramic membrane. In this study, filtration experiments were carried out using a mixture of humic acid and kaolin which simulated surface water under constant pressure to reveal fouling characteristics of the filtration of the diatomite ceramic membrane. The results showed that the removal rate of VU254 was 52%~70%, and turbidity was 90%~95% when treat mixed water of 5-10mg/L kaolin and humic acid. And membrane surface retention and membrane pore adsorption were the mainly removal routes. And the flux slowly decreases, rapidly decreases, gradually decreases and stabilizes were three processes of diatomite ceramic membrane fouling. And the first and third stages of membrane fouling mainly caused by complete blocking, and the second stage was mainly controlled by standard blocking. The study found that humic acid would cause both the pore blocking and the fouling of the membrane surface when turbidity was present, especially the membrane surface pollution, it was the major factor of diatomite ceramic membrane fouling.

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Microcrystalline Cellulose-Blended Polyethersulfone Membranes for Enhanced Water Permeability and Humic Acid Removal

Membranes ◽

10.3390/membranes11090660 ◽

2021 ◽

Vol 11 (9) ◽

pp. 660

Author(s):

Amirul Islah Nazri ◽

Abdul Latif Ahmad ◽

Mohd Hazwan Hussin

Keyword(s):

Humic Acid ◽

Pore Size ◽

Composite Membrane ◽

Microcrystalline Cellulose ◽

Pure Water ◽

Water Flux ◽

Composite Membranes ◽

Size Exclusion ◽

Inversion Method ◽

Water Contact

A novel polyethersulfone (PES)/microcrystalline cellulose (MCC) composite membrane for humic acid (HA) removal in water was fabricated using the phase inversion method by blending hydrophilic MCC with intrinsically hydrophobic PES in a lithium chloride/N,N-dimethylacetamide (LiCl/DMAc) co-solvent system. A rheological study indicated that the MCC-containing casting solutions exhibited a significant increase in viscosity, which directly influenced the composite membrane’s pore structure. Compared to the pristine PES membrane, the composite membranes have a larger surface pore size, elongated finger-like structure, and presence of sponge-like pores. The water contact angle and pure water flux of the composite membranes indicated an increase in hydrophilicity of the modified membranes. However, the permeability of the composite membranes started to decrease at 3 wt.% MCC and beyond. The natural organic matter removal experiments were performed using humic acid (HA) as the surface water pollutant. The hydrophobic HA rejection was significantly increased by the enhanced hydrophilic PES/MCC composite membrane via the hydrophobic–hydrophilic interaction and pore size exclusion. This study provides insight into the utilization of a low-cost and environmentally friendly additive to improve the hydrophilicity of PES membranes for efficient removal of HA in water.

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