Esmaeili Mohammadamin, Virtanen Tiina, Lahti Jussi, Mänttäri Mika, Kallioinen Mari
LUT School of Engineering Science, Department of Separation and Purification Technology, LUT University, 53850 Lappeenranta, Finland.
LUT Re-Source Platform, LUT University, P.O. Box 20, 53851 Lappeenranta, Finland.
Membranes (Basel). 2019 Apr 24;9(4):56. doi: 10.3390/membranes9040056.
Fouling as an intricate process is considered as the main obstacle in membrane technologies, and its control is one of the main areas of attention in membrane processes. In this study, a commercial polyethersulfone ultrafiltration membrane (MWCO: 4000 g/mol) was surface modified with different concentrations of vanillin as an antifouling and hydrophilicity promoter to improve its performance. The presence of vanillin and its increasing adsorption potential trends in higher vanillin concentrations were clearly confirmed by observable changes in FTIR (Fourier transform infrared) spectra after modification. Membranes with better hydrophilicity (almost 30% lower contact angle in the best case) and higher polyethylene glycol solution (PEG) permeability were achieved after modification, where a 35-38% increase in permeability of aqueous solution of PEG was perceived when the membrane was modified at the highest exposure concentration of vanillin (2.8 g/L). After filtration of wood extract, surface modified membrane (2.8 g/L vanillin) showed better antifouling characteristics compared to unmodified membrane, as indicated by approximately 22% lower pure water flux reduction, which in turn improved the separation of lignin from the other organic compounds present in wood extract.
污垢形成作为一个复杂的过程，被认为是膜技术的主要障碍，而对其进行控制是膜工艺中主要关注的领域之一。在本研究中，使用不同浓度的香草醛作为防污和亲水性促进剂对商用聚醚砜超滤膜（截留分子量：4000 g/mol）进行表面改性，以提高其性能。改性后傅里叶变换红外光谱（FTIR）的明显变化清楚地证实了香草醛的存在及其在较高香草醛浓度下增加的吸附势趋势。改性后获得了具有更好亲水性（在最佳情况下接触角降低近30%）和更高聚乙二醇溶液（PEG）渗透率的膜，当膜在香草醛最高暴露浓度（2.8 g/L）下改性时，PEG水溶液的渗透率提高了35 - 38%。过滤木材提取物后，表面改性膜（2.8 g/L香草醛）与未改性膜相比表现出更好的防污特性，纯水通量降低约22%，这反过来改善了木质素与木材提取物中其他有机化合物的分离。
