Separation of major and minor lipid components using supercritical CO2 coupled with cross-flow reverse osmosis membrane filtration

2018 ◽  
Vol 551 ◽  
pp. 333-340 ◽  
Author(s):  
Karina Araus ◽  
Feral Temelli
2007 ◽  
Vol 56 (8) ◽  
pp. 161-168 ◽  
Author(s):  
A.R.A. Razak ◽  
Z. Ujang ◽  
H. Ozaki

Endocrine disrupting chemicals (EDCs) are the focus of current environmental issues, as they can cause adverse health effects to animals and human, subsequent to endocrine function. The objective of this study was to remove a specific compound of EDCs (i.e. pentachlorophenol, C6OCL5Na, molecular weight of 288 g/mol) using low pressure reverse osmosis membrane (LPROM). A cross flow module of LPROM was used to observe the effects of operating parameters, i.e. pH, operating pressure and temperature. The design of the experiment was based on MINITABTM software, and the analysis of results was conducted by factorial analysis. It was found that the rejection of pentachlorophenol was higher than 80% at a recovery rate of 60 to 70%. The rejection was subjected to increase with the increase of pH. The flux was observed to be increased with the increase of operating pressure and temperature. This study also investigated the interaction effects between operating parameters involved.


2012 ◽  
Vol 441 ◽  
pp. 584-588
Author(s):  
San Chuan Yu ◽  
Zhi Wen Chen ◽  
Mei Hong Liu ◽  
Jing Wei Zhao

In view of the water shortage, the increasingly severe regulations as well as the release thresholds, it is becoming increasingly necessary to reuse the textile effluents. This work concerned the treatment of textile plant effluent after conventional biological processing by membrane technology for water reuse. Desal5 DK nanofiltration (NF) membrane and BW30 reverse osmosis (RO) membrane were investigated in this study in terms of COD and color removal, salinity reduction as well as permeate flux through cross-flow permeation tests. The results showed that the Desal5 DK nanofiltration membrane exhibited higher stabilized water permeability and flux decline than the reverse osmosis membrane because of its higher porosity and tendency towards fouling. The BW30 reverse osmosis membrane reduced salinity to a great extent than the Desal5 DK nanofiltration membrane. While the nanofiltration membrane exhibited better COD removal efficiency compared to the RO membrane, possibly due to its sieving removal mechanism. The treated water with good enough quality could be recycled back into the process, thereby offering economical benefits by reducing the water consumption and wastewater treatment cost.


2005 ◽  
Vol 70 (1) ◽  
pp. 107-114 ◽  
Author(s):  
S.S. Madaeni ◽  
H. Daneshvar

Membrane technologies in general and reverse osmosis in particular have been employed for the concentrating of solutions. In this study, the concentrating of a heat sensitive alizarin extracted from madder root was realized using an FT30 reverse osmosis membrane. The effects of cross flow velocity, transmembrane pressure and pH on the flux and rejection were studied. Increasing the transmembrane pressure increased the flux while the rejection was constant. At pH 7-8, the highest flux was achieved. This study showed that reverse osmosis is the process of choice for the concentrating of alizarin solutions. The optimum operating conditions were 1.0 m/s cross flow velocity, 16 bars transmembrane pressure and pH 7. The system was tested for 12 h without severe fouling problems.


2016 ◽  
Vol 94 ◽  
pp. 42-51 ◽  
Author(s):  
Monique H. Vingerhoeds ◽  
Mariska A. Nijenhuis-de Vries ◽  
Nienke Ruepert ◽  
Harmen van der Laan ◽  
Wender L.P. Bredie ◽  
...  

Processes ◽  
2021 ◽  
Vol 9 (10) ◽  
pp. 1833
Author(s):  
Joanna Marszałek ◽  
Renata Żyłła

The aim of the work was to purify model textile wastewater (MTW) using a two-stage membrane filtration process comprising nanofiltration (NF) and reverse osmosis (RO). For this purpose, a nanofiltration membrane TFC-SR3 (KOCH) and reverse osmosis membrane AG (GE Osmonics) were used. Each model wastewater contained a selected surfactant. The greatest decrease in flux in the initial phase of the process occurred for the detergents based on fatty-acid condensation products. An evident decrease in performance was observed with polysiloxane-based surfactants. No fouling effect and high flux values were observed for the wastewater containing a nonionic surfactant based on fatty alcohol ethoxylates. During RO, a significantly higher flux and lower resistance were observed for the feed that originally contained the anionic agent. For the MTW containing the nonionic surfactant, the conductivity reduction ranged from 84% to 92% depending on the concentrate ratio at the consecutive stages of RO. After treatment, the purified wastewater was reused in the process of dyeing cellulose fibers with reactive dyes. The research confirmed that textiles dyed with the use of RO filtrates did not differ in quality of dyeing from those dyed in pure deionized water.


2016 ◽  
Vol 520 ◽  
pp. 964-971 ◽  
Author(s):  
N.M. Farhat ◽  
M. Staal ◽  
Sz.S. Bucs ◽  
M.C.M. Van Loosdrecht ◽  
J.S. Vrouwenvelder

Author(s):  
H. K. Plummer ◽  
E. Eichen ◽  
C. D. Melvin

Much of the work reported in the literature on cellulose acetate reverse osmosis membranes has raised new and important questions with regard to the dense or “active” layer of these membranes. Several thickness values and structures have been attributed to the dense layer. To ensure the correct interpretation of the cellulose acetate structure thirteen different preparative techniques have been used in this investigation. These thirteen methods included various combinations of water substitution, freeze drying, freeze sectioning, fracturing, embedding, and microtomy techniques with both transmission and scanning electron microscope observations.It was observed that several factors can cause a distortion of the structure during sample preparation. The most obvious problem of water removal can cause swelling, shrinking, and folds. Improper removal of embedding materials, when used, can cause a loss of electron image contrast and, or structure which could hinder interpretation.


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