A wastes-based hierarchically structured cellulose membrane: Adsorption performance and adsorption mechanism

It was imperative to expeditiously investigate novel avenues for the valorization of agricultural waste biomass crop straws. The straws represented promising substrates to design eco-friendly adsorbents for the effective treatment of complex dyeing wastewater owing to their widespread availability, low cost, easy production, and environmental friendliness. Despite the advantages, developing adsorbents with versatile uses, antibacterial properties, and strong mechanical qualities remained a challenge. Herein, a sustainable waste treatment strategy is put forward by developing multifunctional adsorbents derived from agricultural waste. The adsorbents are designed to synchronously adsorb the typical contaminants such as organic molecule (methylene blue, MB) and heavy metal ions (cadmium ion, Cd2+) in dyeing wastewater. Through the assembly of cellulose fibers, multiscale cellulose membrane (MCM) substrates with enhanced two-dimensional (2D) structure were simply fabricated from biomass crop straws. Coating functional copper phosphate (CP) nanoflakes on the MCM substrate effectively constructed the hierarchical structure to achieve the synchronous adsorption. The synergistic effects of electrostatic attraction, hydrogen bonding and coordination greatly prompted the adsorption process. Furthermore, the multifunctional adsorbents were imparted with satisfactory antibacterial properties, thereby expected to solve the problem of membrane fouling in wastewater. Hierarchically structured copper phosphate @ cellulose antibacterial adsorbents (CP@MCM) exhibit huge application potential in the resource utilization of agricultural waste and effective treatments for dyeing wastewater.