Hydrophobic Eutectics-based Supramolecular Gels and Cellulose-based Nanosponges: Breakthrough Solutions for Water Remediation

Clean water is a fundamental goal of the 2030 Agenda for Sustainable Development ^[1] and the European Green Deal’s Zero Pollution Action Plan ^[2], making water remediation a critical focus in research. Conventional extraction techniques like dispersive liquid–liquid and solid–liquid microextraction face challenges, including the use of volatile organic solvents and non-sustainable sorbents with limited capacity.

This study addresses these challenges by introducing new classes of sustainable materials based on hydrophobic non-ionic eutectic solvents (HESs) ^[3]. HESs offer several advantages, including being chloride-free and easy to prepare from natural precursors, 100% atom economy, and high sustainability ^[4]. To expand their use, two innovative HES-based materials are developed: hydrophobic eutectogels (HEGs) and HES-loaded cellulose nanosponges (HECSs).

HEGs are supramolecular gels formed by the rapid thermoreversible self-assembly of low molecular weight gelators ^[3]. HECSs are materials obtained by combination of HESs with peculiar aerogels composed of derivatized cellulose ^[5], a crosslinker (either a branched polyethyleneimine or gelatin) and a co-crosslinker ^[6,7].

The materials’ properties are being investigated both morphologically and mechanically by a multi-technique approach.

Preliminary studies with HEGs and HECSs have demonstrated promising extraction abilities in water remediation. In particular, HEGs and HECSs were used to extract bisphenol A from water, obtaining extraction efficiencies >90%, while menthol leaching rates appeared to be limited (<0,35%).

This comprehensive materials study allows for precise control over their properties, making our systems highly adaptable for various applications.

The development of HEGs and HECSs marks a breakthrough in sustainable water treatment. By overcoming the limitations of current extraction methods, this research offers a safer, more efficient, and eco-friendly solution for removing harmful contaminants. The easy production, combined with easy recovery from the medium, pave the way to possible large-scale use. These materials have the potential to play a crucial role in achieving global clean water goals and advancing the field of green chemistry.