Ultrafiltration of Fucus vesiculosus Extracts Under Different Operating Conditions

Abstract

The interest in separating and concentrating bioactives and minerals from seaweeds extracts is growing due to large health bene ts of these substances. The aim of this study was to investigate the separation of components of Fucus vesiculosus seaweed extracts by tangential ultra ltration and apply Hermia's models adapted to cross ow ultra ltration to understand the fouling mechanism. The in uence of membrane cut-off varying from 5 to 150 kDa, cross ow velocity from 0.081 and 0.095 m/s and transmembrane pressure between 2 and 8 bar was studied. The present study revealed that the ultra ltration membranes process was successful in clarifying and still delivering permeates with a high content in iodine. Clari cation was almost completely achieved with 5 kDa polyethersulfone membrane, while the hydrophilic polyethersulfone membrane was not adequate to due to the high retention in iodine. Cake layer formation mathematical model was successfully used to the predict the permeate ux over time. There was evidence that cake layer is the fouling mechanism in the ltration of Fucus vesiculosus extracts, whatever the membrane cross ow velocity or transmembrane pressure, probably due to the high content of these extracts in alginates. Statement Of NoveltySeparation of valuable compounds from Fucus vesiculosus extracts is of great industrial importance and thus insights into its mechanisms and in uence of operational parameters mechanisms that in uence the separation by ultra ltration are needed.This study enabled to sketch those to further optimize the ltration, by providing knowledge on the effect of membrane composition and in uence of the operation parameters molecular weight cut-off, cross-ow velocity and transmembranar pressure. Additionally, the fouling mechanism, which knowledge is needed to further improve the ltration e ciency, was captured to be cake ltration.

Long-Term Performance of Ultrafiltration Membranes: Corrosion Fouling Aspect

“…For instance, the performed membrane cleaning allowed the flux to increase to 130 L/m 2 h under a TMP of 0.4 MPa, while the initial flux was equal to 240 L/m 2 h. Worthy of note, repeating the membrane cleaning operation increased the maximum flux to 170 L/m 2 h. Based on this finding, it can be concluded that, after the filtration of real solutions, the maximum performance of the membranes irretrievably stabilized at a lower level than that noted for the new membranes. Based on the literature review, it should be noted that the P3 Ultrasil 11 solution has been widely used as a chemical cleaning agent for UF membranes fouled with components of various feed solutions, such as oily wastewaters [ 12 , 30 ], separated digestate [ 39 ], orange juice [ 40 , 41 ], Fucus vesiculosus extracts [ 42 ] and spent sulfite liquor [ 43 ].…”