Harnessing Squid Bone for Ultra-Permeable Water Purification Membranes

Area of Science:

• Materials Science
• Environmental Engineering
• Biotechnology

Background:

• Emerging contaminants like nanoplastics, organic dyes, and inorganic particles pose significant challenges to traditional water purification methods.
• There is a growing need for sustainable and efficient water treatment technologies.

Purpose of the Study:

• To introduce novel ultra-permeable membranes derived from carboxylated β-chitin nanofibers from squid bone.
• To evaluate the membranes' performance in removing nanoplastics and organic dyes.
• To assess the sustainability and economic feasibility of the developed membranes.

Main Methods:

• Fabrication of ultra-permeable membranes using carboxylated β-chitin nanofibers.
• Characterization of membrane thickness and pore size.
• Performance testing for pure water flux and rejection of nanoplastics (100 nm and 50 nm) and rhodamine B dye (1.5 nm).
• Mathematical modeling to understand filtration mechanisms.
• Life cycle and techno-economic assessments.

Main Results:

• Membranes exhibited high pure water flux (e.g., 46,207 L·m⁻²·h⁻¹bar⁻¹ for a 124-nm-thick membrane).
• Complete rejection (100%) of 100 nm and 50 nm nanoplastics was achieved with specific membrane thicknesses.
• High rejection (99.2%) of 1.5 nm rhodamine B dye was attained with a 1.8-µm-thick membrane.
• Performance is linked to ultrafine nanofiber dimensions and enhanced porosity via carboxylate-mediated electrostatic repulsion.

Conclusions:

• The developed squid bone-derived chitin nanofiber membranes offer a sustainable and efficient solution for water purification.
• The membranes demonstrate high efficacy in removing emerging contaminants like nanoplastics and organic dyes.
• The approach aligns with circular economy principles, presenting a scalable and eco-friendly innovation for water treatment.