Burts Katsiaryna S, Plisko Tatiana V, Sjölin Mikael, Rodrigues Goncalo, Bildyukevich Alexandr V, Lipnizki Frank, Ulbricht Mathias
Institute of Physical Organic Chemistry, National Academy of Sciences of Belarus, 220072 Minsk, Belarus.
Department of Chemical Engineering, Lund University, 221 00 Lund, Sweden.
Materials (Basel). 2022 Jan 4;15(1):359. doi: 10.3390/ma15010359.
This study deals with the development of antifouling ultrafiltration membranes based on polysulfone (PSF) for wastewater treatment and the concentration and purification of hemicellulose and lignin in the pulp and paper industry. The efficient simple and reproducible technique of PSF membrane modification to increase antifouling performance by simultaneous addition of triblock copolymer polyethylene glycol-polypropylene glycol-polyethylene glycol (Synperonic F108, M =14 × 10 g mol) to the casting solution and addition of polyacrylic acid (PAA, M = 250 × 10 g mol) to the coagulation bath is proposed for the first time. The effect of the PAA concentration in the aqueous solution on the PSF/Synperonic F108 membrane structure, surface characteristics, performance, and antifouling stability was investigated. PAA concentrations were varied from 0.35 to 2.0 wt.%. Membrane composition, structure, and topology were investigated by Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and scanning electron microscopy (SEM). The addition of PAA into the coagulation bath was revealed to cause the formation of a thicker and denser selective layer with decreasing its pore size and porosity; according to the structural characterization, an interpolymer complex of the two additives was formed on the surface of the PSF membrane. Hydrophilicity of the membrane selective layer surface was shown to increase significantly. The selective layer surface charge was found to become more negative in comparison to the reference membrane. It was shown that PSF/Synperonic F108/PAA membranes are characterized by better antifouling performance in ultrafiltration of humic acid solution and thermomechanical pulp mill (ThMP) process water. Membrane modification with PAA results in higher ThMP process water flux, fouling recovery ratio, and hemicellulose and total lignin rejection compared to the reference PSF/Synperonic F108 membrane. This suggests the possibility of applying the developed membranes for hemicellulose concentration and purification.
本研究涉及用于废水处理以及纸浆和造纸工业中半纤维素和木质素浓缩与提纯的基于聚砜（PSF）的防污超滤膜的开发。首次提出了一种高效、简单且可重复的PSF膜改性技术，即通过向铸膜液中同时添加三嵌段共聚物聚乙二醇 - 聚丙二醇 - 聚乙二醇（Synperonic F108，M = 14×10³ g/mol）以及向凝固浴中添加聚丙烯酸（PAA，M = 250×10³ g/mol）来提高防污性能。研究了水溶液中PAA浓度对PSF/Synperonic F108膜结构、表面特性、性能和防污稳定性的影响。PAA浓度在0.35至2.0 wt.%之间变化。通过傅里叶变换红外光谱（FTIR）、X射线光电子能谱（XPS）、原子力显微镜（AFM）和扫描电子显微镜（SEM）研究了膜的组成、结构和拓扑结构。结果表明，向凝固浴中添加PAA会导致形成更厚且更致密的选择性层，其孔径和孔隙率减小；根据结构表征，在PSF膜表面形成了两种添加剂的聚合物间络合物。膜选择性层表面的亲水性显著增加。与参比膜相比，发现选择性层表面电荷变得更负。结果表明，PSF/Synperonic F108/PAA膜在腐殖酸溶液超滤和热磨机械浆厂（ThMP）工艺用水方面具有更好的防污性能。与参比PSF/Synperonic F108膜相比，用PAA对膜进行改性可使ThMP工艺用水通量、污垢恢复率以及半纤维素和总木质素截留率更高。这表明所开发的膜可用于半纤维素浓缩与提纯。
