Membrane distillation (MD) is a promising technology for treating high-salinity mine water. However, MD membranes are known to have low membrane flux and are prone to fouling. In this study, we used the cost-effective and controllable vapor-induced phase separation (VIPS) technology to prepare polyvinylidene difluoride (PVDF) membranes, replacing the traditional immersion precipitation method and optimizing the membrane structure by including LiCl and acetone as porogen in the casting solution. The results showed that the membrane prepared using the VIPS method exhibited a highly open interconnected porous surface. Unlike traditional MD membranes with a dense epidermal layer and large finger-like pores, these optimized membranes had a symmetrical and uniform internal structure, leading to a high flux of 8.62 kg·(m²·h)⁻¹ during direct contact membrane distillation testing. Different porogens produced varied results on the VIPS process and varying effects on membrane structure. The use of LiCl promoted the formation of PVDF β-phase, resulting in a decrease in the number of spherical nodules on the membrane surface, as well as improved density and smoothness. Consequently, this reduced fouling risk during membrane distillation while slightly decreasing membrane flux. On the other hand, acetone rapidly evaporated during the VIPS process, facilitating pre-gelatinization and α-phase formation of PVDF. This concurrent effect effectively restricted excessive nodule growth on the membrane surface, endowing the membrane with antifouling capabilities while preserving high flux.

膜蒸馏（MD）是一种很有前景的高盐度矿井水处理技术。然而，众所周知，MD 膜的膜通量较低，并且容易结垢。在本研究中，我们采用经济有效且可控的气相诱导相分离（VIPS）技术制备聚偏二氟乙烯（PVDF）膜，取代传统的浸没沉淀方法，并通过在膜中加入LiCl和丙酮作为致孔剂来优化膜结构。铸造解决方案。结果表明，采用VIPS方法制备的膜表现出高度开放的互连多孔表面。与具有致密表皮层和大指状孔的传统MD膜不同，这些优化膜具有对称且均匀的内部结构，在直接接触膜蒸馏测试中产生8.62 kg·(m ² ·h) ^-1的高通量。不同的致孔剂对 VIPS 过程产生不同的结果，并对膜结构产生不同的影响。 LiCl的使用促进了PVDF β相的形成，导致膜表面球形结节的数量减少，并提高了密度和光滑度。因此，这降低了膜蒸馏过程中的结垢风险，同时略微降低了膜通量。另一方面，丙酮在 VIPS 过程中迅速蒸发，促进 PVDF 的预糊化和 α 相形成。这种并发效应有效地限制了膜表面结节的过度生长，赋予膜防污能力，同时保持高通量。