The Georgia Institute of Technology has develop an alternative to thermally driven distillation routes. Prompted by the energy-intensive nature of chemical separation processes critical in chemical manufacturing, materials were modified with atomic-scale metal oxide networks, resulting in membranes that can perform chemical separations at a lower energy consumption levels and can withstand harsh solvent-rich chemical streams than traditionally seen.
Metal-containing vapors are infused into the prefabricated membrane by application of vapor phase infiltration technology. This results in a hybrid membrane that demonstrates improved separation performance in various solvents. The metal oxide networks protects the membranes from swelling or dissolving in solvents, as confirmed during tests conducted using tetrahydrofuran, dichloromethane and chloroform. The hybrid membranes remained stable for several months and proved selective, successfully differentiated aromatic molecules separated in size by as little as 0.2 nanometers.
Image caption: An elemental map collected with electron microscopy of a fractured cross-section of hybrid hollow fiber membrane with a radius of about 500 μm. Green dots signify locations of the metal oxide within the membrane. Source: Georgia Institute of Technology.