Electrochemical Regeneration of Highly Stable and Sustainable Cellulose/Graphene Adsorbent Saturated with Dissolved Organic Dye

Abstract

Electrochemical regeneration of adsorbents presents a cost-effective and environmentally friendly approach. Yet, its application to 3D structured adsorbents such as cellulose/graphene-based aerogels remains largely unexplored. This study introduces a method for producing these aerogels, highlighting their significant adsorption capacity for dissolved organic pollutants and resilience during electrochemical regeneration. By adjusting the ratio of hydrophobized cellulose nanofibers to graphene, the aerogels demonstrate a tunable adsorption capacity, ranging from 56 to 228 mg/g. Hydrophobization using oleic acid is vital for maintaining the aerogels’ structural stability in water. Notably, the aerogels maintain structural integrity and efficiency over at least 18 electrochemical regeneration cycles, underscoring their potential for long-term environmental applications. The increase in adsorption capacity observed after regeneration cycles, approximately 10–20% by the fifth cycle, is attributed to electrochemical surface roughening and the creation of new adsorption sites. The tunability and durability of these aerogels offer a sustainable solution for adsorption with electrochemical regeneration technology.

Nano-revolution in heavy metal removal: engineered nanomaterials for cleaner water

“…Cellulose nanofibers were developed by Choi and Lee (2022) using electrospun cellulose acetate deacetylation and subsequent esterification to incorporate thiol groups. According to the Langmuir isotherm (Abuhatab et al, 2023), this modified nanomaterial has adsorption capabilities of 22.0 mg/g, 45.9 mg/g, and 49 mg/g for lead (II), cadmium (II), and copper (II) ions, respectively. The functionalized nanomaterial facilitated the removal of metal ions through complexation interactions between surface thiol groups and divalent metals, showcasing its effectiveness in water remediation.…”