Micro-/Nano-Dual-Scale Porous Composite Membranes for the Separation of Nanopollutants from Water

Abstract

Novel micro-/nano-dual-scale porous composites have been fabricated for nanopollutant filtration by powder metallurgy via four-step sintering of Ti, Al, and Nb powders incorporated with SiO 2 /ZrO 2 /Y 2 O 3 / MgO/ZnO nanoparticles, respectively. Afterward, phase formation, surface morphology, and pore features of the porous composites have been characterized with the changes of heat-treatment temperatures and additive nanoparticles. The separation efficiency of as-prepared Ti-48Al-6Nb porous alloy and porous composite membranes for 50 mg/L TiO 2 nanopollutants from pure water can be calculated through determining the change of TiO 2 concentrations after filtration. Compared with the Ti-48Al-6Nb porous alloy membrane with a separation efficiency of 89.91%, all porous composite membranes can enhance the separation efficiency up to 99.80%. In particular, favorable contributions of the porous composite membrane with nano-SiO 2 are further ascertained by maintaining a high separation efficiency of above 99.95% after repeated filtration of 100 times.

Ti-40Al-10Nb-10Cr Porous Microfiltration Membrane with Hierarchical Pore Structure for Particulate Matter Capturing from High-Temperature Flue Gas

“…The immense potential in energy conversion and storage, adsorption and separation applications has generated significant interest in the design and synthesis of hierarchically porous materials [1][2][3][4][5]. Hierarchically porous materials have many unique features, such as tunable porous structures, controllable macroscopic morphologies, a large surface area and an easily functionalizable surface, making them some of the most promising engineering structural materials [6][7][8][9][10][11][12][13]. High-temperature flue gases discharged from electric power, petroleum, chemical and metallurgical operations have the characteristics of high temperature (above 800 • C), high oxygen content, high sulfur content, high nitrogen content and large amounts of dust content [7][8][9].…”

“…Hierarchically porous materials have many unique features, such as tunable porous structures, controllable macroscopic morphologies, a large surface area and an easily functionalizable surface, making them some of the most promising engineering structural materials [6][7][8][9][10][11][12][13]. High-temperature flue gases discharged from electric power, petroleum, chemical and metallurgical operations have the characteristics of high temperature (above 800 • C), high oxygen content, high sulfur content, high nitrogen content and large amounts of dust content [7][8][9]. Dust removal from these high-temperature flue gases remains a major challenge due to the formation of blockage caused by particle-containing high-temperature flue gases and the corrosion of dust removal equipment.…”