DSpace Repository :: Browsing by Subject "FILTRACION"

Browsing by Subject "FILTRACION"

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Decontamination of water: adsorption of heavy metals to hematite particles, derived from ferroxane, and a comparison of different filtration process designs
(2014-09) Bühler, Frank; Fidalgo de Cortalezzi, María Marta; Bertini, Liliana María; Wessling, Matthias
"The presence of heavy metal ions in water poses a major environmental health risk to local residents.Industrial waste water often contains heavy metal ions, e.g., chromium, lead and nickel. If the waste water is not properly treated prior to discharge, these highly toxic metal ions may leak into the ground water. A warning example is the highly contaminated river called Matanza-Riachuelo in Argentina. Environmental factors such as diarrheal diseases, respiratory diseases, and cancer are significant public health problems associated with the multiple industries in the basin which are responsible for the high level of heavy metal contamination. This issue is aggravated by inadequate infrastructure in the nearby informal settlements, where residents are left with few options for drinking water. To address this problem, a user-friendly, low energy demanding and low cost treatment technology shall be developed for households, schools or other small-scale application at Instituto Technologico de Buenos Aires (ITBA), Argentina."
Electrostatic interactions in virus removal by ultrafiltration membranes
(2018-02) Gentile, Guillermina José; Cruz, Mercedes Cecilia; Rajal, Verónica Beatriz; Fidalgo de Cortalezzi, María Marta
"Ultrafiltration membranes are increasingly used in potabilization to remove viral particles. This removal is controlled by electrostatic repulsion, attachment and size exclusion. The effect of electrostatic interaction in virus filtration was investigated. Our work included characterization of bacteriophage PP7 and polyethersulfone membrane with respect to size and surface charge; the removal of this bacteriophage at laboratory scale by ultrafiltration membrane process and the mechanism and limitations were analyzed and discussed under DLVO and XDLVO theories. A partial removal of the bacteriophage was achieved; however, enhanced separation may be achieved considering that the process is affected by the aqueous matrix. The presence of divalent cations diminished the effectiveness of the procedure as opposed to monovalent cations and species with amphoteric behavior such as bicarbonate. DLVO and XDLVO predicted the interactions studied between bacteriophage PP7 and polyethersulfone membrane."
Enhanced retention of bacteria by TiO2 nanoparticles in saturated porous media
(2016-08) Gentile, Guillermina José; Fidalgo de Cortalezzi, María Marta
"The simultaneous transport of TiO2 nanoparticles and bacteria Pseudomonas aeruginosa in saturated porous media was investigated. Nanoparticle and bacterium size and surface charge were measured as a function of electrolyte concentration. Sand column breakthrough curves were obtained for single and combined suspensions, at four different ionic strengths. DLVO and classical filtration theories were employed to model the interactions between particles and between particles and sand grains. Attachment of TiO2 to the sand was explained by electrostatic forces and these nanoparticles acted as bonds between the bacteria and the sand, leading to retention. Presence of TiO2 significantly increased the retention of bacteria in the sand bed, but microorganisms were released when nanomaterial influx ceased. The inclusion of nanomaterials in saturated porous media may have implications for the design and operation of sand filters in water treatment."
Enhancement of the fouling resistance of zwitterion coated ceramic membranes
(2020-08) Storms, Max; Kadhem, Abbas J.; Xiang, Shuting; Bernards, Matthew; Gentile, Guillermina José; Fidalgo de Cortalezzi, María Marta
"Ceramic membranes suffer from rapid permeability loss during filtration of organic matter due to their fouling propensity. To address this problem, iron oxide ultrafiltration membranes were coated with poly(sulfobetaine methacrylate) (polySBMA), a superhydrophilic zwitterionic polymer. The ceramic-organic hybrid membrane was characterized by scanning electron microscopy (SEM) and optical profilometry (OP). Membranes with and without polySBMA coating were subjected to fouling with bovine serum albumin solution. Hydraulic cleaning was significantly more effective for the coated membrane than for the non-coated one, as 56%, 66%, and 100% of the fouling was removed for the first, second, and third filtration cycle, respectively. Therefore, we can highlight the improved cleaning due to an increased fouling reversibility. Although some loss of polymer during operation was detected, it did not affect the improved behavior of the tested membranes."
On the use of espina corona gum as a polymeric additive in water-based drilling fluid
(2022-10) Villada, Yurany; Taverna, María Eugenia; Maffi, Juan M.; Giletta, Sebastián; Casis, Natalia; Estenoz, Diana
"The aim of this work is to evaluate the espina corona gum (ECG) as a sustainable viscosifier or filtration reducer additive in water-based drilling fluids (WBMs) as a potential replacement of guar gum (GG). ECG is a galactomannan isolated from leguminous seeds of Gleditsia amorphoides, trees that grow in South America with viscosifier properties and applications in the food area. ECG was characterized by FTIR, Z potential, intrinsic viscometry, TGA, and steady and oscillatory shear rheological analysis. Moreover, its effect on the main functional properties of WBMs was studied. Fluids containing bentonite (BT), polyanionic cellulose (PAC), GG or ECG were prepared, and rheological, filtration, thermal and structural properties were determined. In order to study the theoretical rheological behavior, several models such as power law, Sisko and Herschel-Bulkley were evaluated. The rheological studies revealed that WBMs containing ECG exhibit higher viscosities in comparison with those with GG. Herschel-Bulkley parameters indicated that the WBMs with high ECG concentration showed higher yield stress. In addition, the presence of ECG improves the thermal stability and filtration properties. The results indicate that ECG can be considered as an innovative, renewable and non-toxic alternative to partially or totally replace GG in WBMs."

Browsing by Subject "FILTRACION"

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