Sandwich Structure Membrane with Enhanced Anti-Swelling Property and Mechanical Strength for Bioethanol Separation by Pervaporation

Abstract

To improve the membrane's anti-swelling and antimechanical damage properties, one polypropylene (PP) membrane was integrated into the conventional dual-layer polydimethylsiloxane/polyamide (PDMS/PA) membrane, forming a new sandwich structure PP/PDMS/PA composite membrane with better durability during the ethanol separation from the practical fermentation broth. In the sandwich structure, the top PP layer protected the fragile layer, PDMS layer, which was inlaid outside the PDMS/PA membrane, from being directly exposed to the fermentation broth and the external mechanical damage. The middle PDMS layer was the separation layer and glued the PP and PA layers together. The bottom PA layer was the supportive layer. The swellings of the PP/PDMS/PA membrane in water, ethanol, and fermentation broth were decreased by 21, 6, and 17%, respectively, compared with those of the PDMS/PA membrane. The tensile strength, Young's modulus, breaking strength, and anti-impact property of the PP/PDMS/PA membrane were increased by 223, 18, 724, and 196%, respectively.

Holmium-Containing Metal-Organic Frameworks as Modifiers for PEBA-Based Membranes

“…These polymers have a number of properties, such as flexibility, chemical resistance and strength, that make them promising for use in membrane technologies [ 54 , 55 , 56 ]. Recently, a number of studies have been carried out on the use of mixed matrix membranes based on PEBA not only for the separation of gases [ 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 ] but also for the extraction of various biofuel components [ 67 , 68 ], alcohols [ 69 , 70 ], desulphurization [ 71 ], alcohol dehydration [ 72 ], esterification [ 73 ] and pervaporation [ 74 , 75 ]. The high degree of combinatoriality in the preparation of block copolymers makes it possible to obtain a large number of commercially available polymers with different compositions and properties [ 76 ].…”