Recent advances in sodium alginate‐based membranes for dehydration of aqueous ethanol through pervaporation

Abstract

Sodium alginate (SA) is a progressive material for membrane fabrication. The technological development of SA-based membranes has made a significant contribution to the separation techniques, especially in aqueous organic solutions. The outstanding performance of SA is attributed to its outstanding structural flexibility and hydrophilicity. In view of structural characteristics, SA membranes have immense utilization in the pervaporation separation of organics. Among various organics, dehydration of aqueous ethanol is employed as a standard to check the success of pervaporation (PV) membrane. Because ethanol and water have comparable molecular sizes, thus difficult to extract water from aqueous ethanol mixtures than it is for other organics. A literature survey shows that wide-ranging data are available on the PV performance of SA and its modified membranes. In this context, the present review addresses the recent advances made in SA membranes for enhanced ethanol dehydration performance during the last decade.Available data since 2010 has been compiled for grafted, crosslinked, blend, mixed matrix, and composite hybrid sodium alginate membranes in terms of separation factor, permeation flux, and pervaporation separation index PSI. The data are assessed with reference to the effect of feed composition, membrane selectivity, flux, and swelling behavior.

Recent Advances in Separation and Analysis of Chiral Compounds

“…Membranes with enantioselective permeability are another common separation media. Compared with chromatographic separation techniques that are usually performed in an analytical scale, membrane separation has greater potential for large preparative scale separation (more than kilogram level) in pharmaceutical and chemical engineering fields. , Conventional chiral membranes are prepared from polysaccharides (chitosan and cellulose), sodium alginate, poly­(substituted acetylene), poly­(amino acids), and lipids. − Industrial application for most chiral membranes is still difficult because of insufficient enantioselectivity under high flux following the facilitated transport mechanism. Because the performance of membranes essentially depends on different interactions between enantiomers and chiral discriminating units of membranes during transport process, the exploration of new chiral materials with high selectivity, excellent permeability, good stability, and long-time operation has been the main focus in recent years, represented by improved polymers, porous crystalline materials, carbon nanomaterials, and micro/nanochannels. − These up-to-date membrane materials have continued to grow for chiral separation in the past two years.…”

Novel Polyelectrolyte Complex Membranes Containing Carboxymethyl Cellulose–Gelatin for Pervaporation Dehydration of Azeotropic Bioethanol for Biofuel

“…Among the separation techniques, pervaporation (PV) is quite an effective method for the dehydration of organic substances, especially for separating azeotropic mixtures [ 6 , 7 ]. It has numerous benefits over the traditional distillation process, such as low cost, low energy intake, eco-friendly, and simplest operation [ 8 , 9 ].…”

Pervaporation Membranes Based on Polyelectrolyte Complex of Sodium Alginate/Polyethyleneimine Modified with Graphene Oxide for Ethanol Dehydration

“…SA as a natural polysaccharide obtained from algae is actively used in the food, biomedical, textile, and cosmetic industries due to its advantages such as environmental friendliness, solubility in water, biocompatibility, and low cost [15][16][17]. It is also a progressive membrane material for fuel cells, nanofiltration, ultrafiltration, and especially for pervaporation [18][19][20][21]. SA membranes are characterized by insufficient permeability and low stability in dilute aqueous solutions.…”

“…This is a significant drawback for their use in industry. Procedures such as grafting, cross-linking, blending, and the creation of mixed matrix and composite SA-based membranes have been carried out to improve performance [20]. In this work, the improvement of SA was carried out by introducing PEI for the creation of a PEC and graphene oxide (GO).…”