Identification and optimization of key parameters in preparation of thin film composite membrane for water desalination using multi-step statistical method

Correlations between conditions of the polyaniline (PANI) interlayer formation on the surface of a polysulfone (PSF) porous membrane substrate and the structure and performance of thin-film composite (TFC) membranes for nanofiltration with a polyamide (PA) selective layer prepared via interfacial polymerization (IP) were studied. It was shown that application of the PANI layer significantly enhanced hydrophilicity (the water contact angle decreased from 55 ± 2° down to 26-49 ± 2°), decreased pore size and porosity, and increased the surface roughness of the selective layer surface of porous PSF/PANI membrane substrates due to the formation of bigger PANI globules, which affect the formation of the PA layer of TFC membranes via IP. It was shown that the application of the PANI intermediate layer yielded the formation of a thinner PA selective layer, a decline in surface roughness, and an increase in hydrophilicity (the water contact angle declined from 28 to <10°) and crosslinking degree of the selective layer of TFC NF membranes. The developed approach allows us to enhance the water permeation up to 45-64 L·m-2·h-1 at ΔP = 0.5 MPa and improve membrane selectivity (rejection coefficient of MgSO4->99.99%; LiCl-5-25%; sulfadimetoxine-80-95%) and also ensure enhanced long-term operational stability of TFC nanofiltration membranes with a PANI interlayer. Moreover, Mg2+/Li+ separation factor values were found to increase to 37 and 58 for PANI-modified membranes compared to 9 and 8 for the reference NF-PSF membranes.

An integrated statistic and systematic approach to study correlation of synthesis condition and desalination performance of thin film composite membranes

Interfacially polymerized thin-film composite polyamide membranes: Effects of annealing processes on pervaporative dehydration of aqueous alcohol solutions

Facile fabrication of ceramic-based highly permeable composite nanofiltration membranes by in-situ interfacial polymerization

This study was aimed to develop a customised thin film composite (TFC) membrane for the separation in biorefinery. After the biomass hydrolysis stage, sugars component (i.e. glucose and xylose) need further refinement to remove any inhibitor (i.e. acetic acid) that can decrease the yield of the product during the fermentation stage. Substrate layer properties and the condition of thin film formation during interfacial polymerisation (IP) influenced the performance of the TFC membrane. Not much attention is given on the effects of substrate membrane properties as most support membranes were purchased commercially. Polyethersulfone (PES) membrane substrate was fabricated in the current study at different PES concentration range of 15 wt% to 23 wt%. IP was performed using the piperazine and trimesoyl chloride monomers. As the PES concentration in the membrane substrate increased, the pure water permeability (PWP) decreased. The PWP of the membrane substrate prepared from 15 % PES and 23 % PES were 231.67 ± 16.59 L/m2.h.bar and 24.49 ± 6.54 L/m2.h.bar. After the IP, the PWP decreased to the range of nanofiltration. The PWP value were 28.07± 5.42 L/m2.h.bar and 3.94 ± 1.21 L/m2.h.bar for the TFC membrane prepared using 15 % PES and 23 % PES membrane support. TFC membrane prepared using 23 % PES showed the rejection value 24.07 ± 5.96 % of xylose, 47.56 ± 1.99 % of glucose and 2.67 ± 1.05 % of acetic acid. This is corresponding to the ideal separation factor of 1.45 ± 0.06 for xylose/glucose, 1.86 ± 0.05 for acetic acid/glucose and 1.29 ± 0.09 for acetic acid/xylose.

Improved performance of thin-film composite membrane with PVDF/PFSA substrate for forward osmosis process

Most hydrolysis studies on biomass in Malaysia produce high amount of xylose and glucose compared to other monosaccharides and most of them are acidic. Thin film composite (TFC) membrane developed via interfacial polymerization using triethanolamine (TEOA) and trimesoyl chloride (TMC) as monomers allows separation at low pH to occur without damaging its performance. Comparative studies were carried out on membranes with and without the thin film layer formed via interfacial polymerization on the polyethersulfone (PES) support. The surfaces of the membranes were characterized by field emission scanning electronic microscopy (FESEM), attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, and hydrophilicity via contact angle measurement. In addition, the performance and uncharged solute fouling behaviour of TFC membrane were also investigated. The TFC membrane used for characterization purposes was prepared at TEOA concentration of 4 % w/v in 1 × 10-6 M sodium hydroxide solution, TMC concentration of 0.25 % w/v in pure hexane, reaction time of 45 minutes, and cured at temperature of 60 °C. Characterization results showed a huge different between the synthesized TFC membrane and the un-synthesized PES membrane in term of surface properties and morphology. Nanofiltration results indicate that the formation of thin layer on top of PES support membrane improved the separation performance compared to PES support membrane. The synthesised polyester TFC membrane have irreversible fouling of 11.02 (±5.60) % and reversible fouling of 5.59 % using water as cleaning agent.

Formation of thin film composite nanofiltration membrane: Effect of polysulfone substrate characteristics

Preparation of thin film composite nanofiltration membrane with improved structural stability through the mediation of polydopamine

In situ amphiphilic modification of thin film composite membrane for application in aqueous and organic solvents

Preparation and characterization of thin film composite membrane for the removal of water vapor from the flue gas at bench scale

Study on a novel polyester composite nanofiltration membrane by interfacial polymerization of triethanolamine (TEOA) and trimesoyl chloride (TMC): I. Preparation, characterization and nanofiltration properties test of membrane

Novel thin film composite forward osmosis membrane of enhanced water flux and anti-fouling property with N-[3-(trimethoxysilyl) propyl] ethylenediamine incorporated

The role of support layer properties on the fabrication and performance of thin-film composite membranes: The significance of selective layer-support layer connectivity

Effect of lag time in interfacial polymerization on polyamide composite membrane with different hydrophilic sub layers