Pioneering Thin Film Blend Membranes for Advanced Desalination

The quest for sustainable solutions to global water scarcity has led researchers to innovate in the field of water purification and desalination. The recently granted patent to Dr. Jegatha Nambi Krishnan, a distinguished faculty member in the Department of Chemical Engineering at BITS Pilani KK Birla Goa Campus, and V. Kaarthick Raja, her student and co-innovator, marks a significant milestone. Their invention, titled "Thin Film Blend Membrane for Desalination," demonstrates a cutting-edge approach to enhancing desalination technology. 

The patented innovation focuses on the development of a novel thin film blend membrane designed to revolutionize desalination processes. The invention incorporates a blend of two sulfonated polymers: Sulfonated Polyarylene Ether Sulfone (SPAES) and Sulfonated Polybenzimidazole (S-p-PBI). These polymers are blended in a precise ratio to achieve optimal performance. The resulting membrane offers superior metrics in terms of permeability, biofouling resistance, and mechanical robustness.

The invention was driven by the following objectives:

• Enhanced Desalination Efficiency: Achieve high water flux and productivity by creating a thin yet durable active layer.

• Resistance to Fouling: Address the persistent challenge of biofouling by incorporating sulfonated polymers that disrupt biofilm formation.

• Chemical Stability: Ensure resistance to dissolved chlorine and other aggressive chemicals commonly encountered in desalination processes.

• Versatility: Expand the application potential fuel cells and pervaporation processes, apart from desalination.

The thin film blend membrane offers several distinct advantages. It exhibits remarkable biofouling resistance with minimal microbial growth even under conditions that typically promote biofilm formation. The membrane also displays significant chemical versatility due to its free ionic charges that enable further modifications for specialized applications. Additionally, the invention significantly lowers energy demands in desalination processes by reducing biofouling and improving water flux.

Experimental evaluations of the patented membrane against commercial counterparts highlight its superior performance. Scanning electron microscopy (SEM) studies reveal that while commercial membranes succumb to biofilm growth, the patented blend membrane remains pristine, underscoring its effectiveness in harsh operational environments.

The granting of this patent not only underscores the excellence of BITS Pilani’s research ecosystem but also offers a promising tool to mitigate water scarcity challenges. By combining advanced materials science with practical applications, this invention paves the way for a sustainable future where clean water is accessible to all.