To enhance anti-fouling properties of polymeric membranes during apple juice clarification, PSF/PEI (20/2 wt%) ultrafiltration (UF) membranes were modified with TiO₂ and Al₂O₃ nanoparticles using the phase inversion method. Turbid apple juice samples were clarified using cross-flow membrane filtration system. All fabricated nanocomposite UF membranes had higher apple juice flux values than PSF/PEI membrane. Membrane prepared with 0.01% TiO₂ (UFT1) had the highest apple juice flux (at steady state, 44.6 L/m²h). The FRR (%) value of TiO₂ and Al₂O₃ incorporated UF membranes was between 90.9–94.0% and 79.6–97.6%, respectively, and these FRR values were higher than that of PSF/PEI membrane (UF2, 60.3%). Porosity and hydrophilicity of the UF membranes significantly increased with the addition of nanoparticles and the highest porosity and hydrophilicity was achieved in the 0.01% TiO₂ incorporated UF membrane (UFT1) membrane. Higher flux recovery ratio (FRR) and lower relative flux reduction (RFR) values of Al₂O₃ and TiO₂ incorporated nanocomposite membranes, compared with the unmodified membrane, demonstrated the enhancement in the anti-fouling properties of the PSF/PEI membrane. SEM images of the nanocomposite membranes also proved the nanoparticle incorporation to the PSF/PEI matrix. Color, turbidity, total soluble solid, total phenolic content, and antioxidant capacity of the samples using nanocomposite membranes were better than that of clarified using both commercial and unmodified membranes. TiO₂ incorporated nanocomposite membranes had superior performance than Al₂O₃ incorporated nanocomposite membranes and among these membranes, the ones prepared with the addition of 0.01 wt% TiO₂ exhibit the best performance in terms of clarification of apple juice.

中文翻译：

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使用TiO 2和Al 2 O 3纳米颗粒制备的新一代纳米复合膜澄清苹果汁

为了在苹果汁澄清过程中增强聚合物膜的防污性能，使用相转化方法用TiO ₂和Al ₂ O ₃纳米粒子对PSF / PEI（20/2 wt％）超滤（UF）膜进行了改性。使用错流膜过滤系统澄清浑浊的苹果汁样品。所有制备的纳米复合超滤膜的苹果汁通量值均高于PSF / PEI膜。用0.01％TiO ₂（UFT1）制备的膜的苹果汁通量最高（稳态时为44.6 L / m ² h）。TiO ₂和Al ₂ O ₃的FRR（％）值掺入的超滤膜分别在90.9–94.0％和79.6–97.6％之间，并且这些FRR值高于PSF / PEI膜（UF2，60.3％）。UF膜的孔隙率和亲水性随着纳米颗粒的添加而显着增加，并且在掺有0.01％TiO _2的UF膜（UFT1）中获得了最高的孔隙率和亲水性。Al ₂ O ₃和TiO _2的通量恢复率（FRR）较高，相对通量减少率（RFR）较低与未改性的膜相比，掺入的纳米复合膜证明了PSF / PEI膜的防污性能得到了增强。纳米复合膜的SEM图像也证明了纳米颗粒结合到PSF / PEI基质中。使用纳米复合膜的样品的颜色，浊度，总可溶性固形物，总酚含量和抗氧化能力均好于使用商品膜和未改性膜的澄清度。掺有TiO _2的纳米复合膜的性能优于掺有Al ₂ O _3的纳米复合膜，在这些膜中，添加了0.01 wt％TiO _2的膜 在澄清苹果汁方面表现出最好的性能。