This work shows mixed matrix inorganic membranes prepared by the vacuum-assisted impregnation method, where phenolic resin precursors filled the pore of α-alumina substrates. Upon carbonisation, the phenolic resin decomposed into several fragments derived from the backbone of the resin matrix. The final stages of decomposition (>650 °C) led to a formation of carbon molecular sieve (CMS) structures, reaching the lowest average pore sizes of ~5 Å at carbonisation temperatures of 700 °C. The combination of vacuum-assisted impregnation and carbonisation led to the formation of mixed matrix of CMS and α-alumina particles (CMS-Al2O3) in a single membrane. These membranes were tested for pervaporative desalination and gave very high water fluxes of up to 25 kg m−2 h−1 for seawater (NaCl 3.5 wt%) at 75 °C. Salt rejection was also very high varying between 93–99% depending on temperature and feed salt concentration. Interestingly, the water fluxes remained almost constant and were not affected as feed salt concentration increased from 0.3, 1 and 3.5 wt%.

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The cyclic oxidation behaviors of the as-cast Ti-1100-xNb (x = 0.5, 1.0, 1.5, 2.0) alloys exposed at 650 • C for up to 100 h were systematically investigated. The aim of this work is to explore the in-depth oxidation mechanism by using the oxidation kinetics and the structure of the oxide products. The oxidation kinetics were determined by thermogravimetrically, and the microstructure and composition of the oxidation scale were studied by using XRD and SEM. The results demonstrate that Nb can significantly improve the oxidation resistance. However, the average weight gains of the alloys decrease firstly and then increase with the increase of Nb content. The oxidation kinetics obeys a parabolic model. The Ti-1100-1.0Nb alloy has the lowest k p value, which is 5.7 × 10 −13 g 2 cm −4 s −1 . The surface oxidation products are mainly composed of massive or acicular rutile-TiO 2 , Ti x O (x = 3, 6), NbO 2 and Al 2 O 3 . Besides, Al 2 (MoO 4 ) 3 oxide is also presented on the oxidation surface of the Ti-1100-1.5Nb alloys. Ti-1100-1.0Nb alloy shows the best oxidation resistance property revealed by combining weight gains and EDS-SEM element content profiles analysis. The interaction of Nb, O, Ti, and other elements retarded the diffusion of O atoms into the alloys, which improves the oxidation resistance. surface increases, even the TiO 2 particles dissolve [10]. Researches showed that the addition of 5-10 at.% Nb could improve the oxidation resistance of Ti-Al alloys [11,12]. The effects of Nb atoms on oxidation behavior could be summarized as [13][14][15][16]: (1) Nb replaced the Ti 4+ in TiO 2 , leading to a reduce of O 2− vacancy, which hampered the diffusion of O ion. (2) Nb could improve the activity of Al and promote the formation of the density Al 2 O 3 oxide film in TiO 2 oxide-layer, which can reduce the solubility of O atoms in oxide-layer. (3) Nb could reduce the solubility of O in α-Ti phase lattice. However, the solid solubility of Nb in titanium alloys is limited, and the interaction of Nb with Al, Sn, Zr, Mo, and Si in the Ti-1100 alloy can form the secondary phase and change the surface oxide structure [7]. With increasing Nb element, excessive Nb segregates in the grain boundary, which may result in the oxide scales cracking and high temperature oxidation resistance depreciation [8,17]. The content of Nb in the near α titanium alloy is usually between 0.7-1.0 wt.% [18], and the excess Nb content can be selected as 1.5 and 2.0 wt.%.Thus, the effect of Nb content (0.5, 1.0, 1.5, 2.0 wt.%) on cyclic oxidation behavior of as-cast Ti-1100 alloys was systematically investigated in this present work. The aim of this study is to explore the in-depth oxidation mechanism from the oxidation kinetics, surface oxidation products, and the cross-section oxidation layer elements distribution.