(20e) Functionalized Nanoporous Ceramic Membranes Towards Low-Cost Electrodialysis
In this work, we investigate the use of a surface-modified inorganic membrane created using sol-gel processing of siloxanes without calcination or sintering. Silica is an advantageous material for membranes because of its excellent durability, extremely low cost and lack of swelling in water. Membrane performance can be tuned by size exclusion (i.e., sub-5nm nanometer pores) and surface functionalization (i.e., silane chemistry) to achieve promising anion and cation-selective performance. Permselectivity and water permeance of these membranes are shown to be superior to an industry standard Neosepta, while area specific resistance has room for improvement. Area-normalized ion exchange capacities and accelerated degradation tests show nearly identical performance between the functionalized ceramic and Neosepta membranes. Design strategies for continued optimization will also be discussed. These promising preliminary results highlight the commercial potential for a new, inexpensive IEM with the potential to elevate the status of electrodialysis as a leading solution to the fresh water crisis.