Effect of poly(vinyl pyrrolidone) concentration and coagulation bath temperature on the morphology, permeability, and thermal stability of asymmetric cellulose acetate membranes

2009 ◽  
Vol 111 (5) ◽  
pp. 2537-2544 ◽  
Author(s):  
Ehsan Saljoughi ◽  
Mohammad Amirilargani ◽  
Toraj Mohammadi
Author(s):  
Rizki Firsta Wahyuliswari ◽  
Siswanto ◽  
Prihartini Widiyanti

Polysulfone is synthetic polymer widely used as basic material for dialyzer membrane and hydrophobic so it tends to cause fouling. Cellulose acetate is non-synthetic, hydrophilic polymer which has low tendency of fouling and has good thermal stability and permeability so it is considered as alternative material for hollow fiber dialyzer. A proper hollow fiber can be achieved by setting a proper temperature of coagulation bath along the spinning process. This research aims to understand the effect of coagulation bath temperature variations on the physical characteristic such as pore size, tensile strength, swelling rate and creatinine clearance of cellulose acetate – D-glucose monohydrate hollow fibers. Hollow fibers were fabricated using spinneret at temperature variations 5°C, 10°C, 15°C dan 20°C. Physical characteristics were estimated by doing morphology test using SEM, tensile test, swelling test towards Simulated Body Fluid (SBF) and filtration test towards creatinine. Result revealed that the hollow fibers from 5°C coagulation bath temperature gives the best characteristic and performance with tensile strength 27,421 N mm-2, pore size 0,0295–0,0858 nm, swelling rate 4,18%, elongation rate 4,4 %, flux rate 1,6032–1,7956 mL cm-2 min-1 and creatinine clearance rate 40,14–48,30% so it is potential to be applied as dialyzer membrane.


2012 ◽  
Vol 18 (3) ◽  
pp. 385-398 ◽  
Author(s):  
Reza Abedini ◽  
Mahmoud Mousavi ◽  
Reza Aminzadeh

In this study, asymmetric pure CA and CA/ TiO2 composite membranes were prepared via phase inversion by dispersing TiO2 nanopaticles in the CA casting solutions induced by immersion precipitation in water coagulation bath. TiO2 nanoparticles, which were synthesized by the sonochemical method, were added into the casting solution with different concentrations. Effects of TiO2 nanoparticles concentration (0 wt. %, 5wt.%, 10wt.%, 15wt.%, 20wt.% and 25wt.%) and coagulation bath temperature (CBT= 25?C, 50?C and 75?C) on morphology, thermal stability and pure water flux (PWF) of the prepared membranes were studied and discussed. Increasing TiO2 concentration in the casting solution film along with higher CBT resulted in increasing the membrane thickness, water content (WC), membrane porosity and pure water flux (PWF), also these changes facilitate macrovoids formation. Thermal gravimetric analysis (TGA) shows that thermal stability of the composite membranes were improved by the addition of TiO2 nanopaticles. Also TGA results indicated that increasing CBT in each TiO2 concentration leads to the decreasing of decomposition temperature (Td) of hybrid membranes.


Membranes ◽  
2018 ◽  
Vol 8 (4) ◽  
pp. 87 ◽  
Author(s):  
Daria Nevstrueva ◽  
Arto Pihlajamäki ◽  
Juha Nikkola ◽  
Mika Mänttäri

Supported cellulose ultrafiltration membranes are cast from a cellulose-ionic liquid solution by the immersion precipitation technique. The effects of coagulation bath temperature and polymer concentration in the casting solution on the membrane morphology, wettability, pure water flux, molecular weight cut-off, and fouling resistance are studied. Scanning electron microscopy, contact angle measurements, atomic force microscopy, and filtration experiments are carried out in order to characterise the obtained ultrafiltration cellulose membranes. The results show the effect of coagulation bath temperature and polymer concentration on the surface morphology and properties of cellulose ultrafiltration membranes. Optimisation of the two parameters leads to the creation of dense membranes with good pure water fluxes and proven fouling resistance towards humic acid water solutions.


2008 ◽  
Vol 8 (9) ◽  
pp. 4461-4469 ◽  
Author(s):  
Lifeng Zhang ◽  
You-Lo Hsieh

Nano-structural features were introduced to ultrafine cellulose acetate (CA) fibers by electrospinning of its mixtures with either poly(vinyl pyrrolidone) PVP or β-cyclodextrin (β-CD) in DMF, followed by dissolution of the added PVP or β-CD. The presence of the charge-holding PVP enabled fiber formation from CA below its entanglement chain length and improved the electrospinning efficiency to produce bicomponent fibers with wide ranging diameters from 30 to 650 nm. At up to 50% contents, the PVP in the bicomponent fibers was phase-separated from CA and, upon removal, resulting in highly angulated fiber surfaces with nanometer-size spherulites and sub-micron size ridges and grooves. Adding β-CD to CA enabled fiber formation at concentrations below the chain entanglement concentration Ce (16.5%). Hydrogen bonding between β-CD and CA, as evident by FTIR, helped to distribute β-CD as individual molecules in the CA matrix and producing more uniform and finer (130–150 nm in diameters) fibers, irrespective of their β-CD contents. Removal of β-CD from the fibers originally containing 40% β-CD, generated nanoporous fibers with 2-nm nanopores and 70% increase in specific surface and doubled pore volume.


2017 ◽  
Vol 19 ◽  
pp. 118 ◽  
Author(s):  
Sathiya Sanmugam ◽  
Norlisa Harruddin ◽  
Syed M Saufi

<p>Acetic acid is a byproduct of acid hydrolysis of biomass during sugar recovery step in biofuel production. Acetic acid can inhibit the enzyme used during fermentation of sugar to the ethanol. Hollow fiber supported liquid membrane (SLM) was used in this study to remove acetic acid from aqueous solution. Liquid membrane was formulated using trioctylamine and 2-ethyl hexanol as a carrier and solvent, respectively. The hollow fiber membrane support was prepared from 15 wt.% polyethersulfone, 42.5 wt.% polyethyleneglycol 200 and 42.5 wt.% dimethylacetamide. The effect of coagulation bath temperature (CBT) at 30<sup>º</sup>C, 40<sup>º</sup>C and 50<sup>º</sup>C during hollow fiber membrane spinning process was investigated. The porosity of the membrane increased as the CBT increased. The porosity of the membrane prepared using CBT of 30ºC, 40<sup>º</sup>C and 50<sup>º</sup>C were 35.7%, 46.7% and 61.6%, respectively. SLM process using hollow fiber membrane prepared at 50ºC of coagulation bath was able to remove 52% of acetic acid from the aqueous solution.</p><p>Chemical Engineering Research Bulletin 19(2017) 118-122</p>


Sign in / Sign up

Export Citation Format

Share Document