Synthesis of gelatin aerogel-containing Al-metal organic framework for the removal of phenolic contaminants from aqueous solutions

Abstract

Considerable amounts phenols and derivatives are found in water bodies in our surrounding environment. However, phenolic waste is extremely difficult to decompose naturally and is highly toxic even at very low concentrations. The unique properties of aerogels allow them to act as potential candidate in different fields, but their applications in adsorption field remain limited. The impressive results of novel aerogels could open new avenues for water remediation and development of new functional aerogel materials. In this study, an aluminum-based metal-organic framework incorporating gelatin (GMA-1.0) aerogel hybrid composite was prepared to remove phenolic compounds, namely phenol, 4-chlorophenol (CP), 2,4-dichlorophenol (DCP), and 2,4,6-trichlorophenol (TCP) from aqueous environments. The as-prepared GMA-1.0 aerogel composite could uptake TCP to the greatest extent (16.56 mg/g) compared to the other forms of phenolic derivatives. Moreover, the prepared GMA-1.0 demonstrated high selectivity and excellent adsorption–desorption performance over four repetitions without loss of adsorption capacity. Special attraction forces involved in adsorption chemistry, i.e., hydrogen bonding, π–π bond interactions, and donor–acceptor complexation, are involved to remove the phenolic compounds from water. Continuous column studies revealed that the Thomas, Adams–Bohart, and Yoon–Nelson models performed well with respect to eliminating phenolic derivatives for the prepared GMA-1.0 aerogels. Based on these findings, it can be concluded that the as-synthesized GMA-1.0 aerogel composite has excellent potential for serving as a novel and effective adsorbent material for practical application in phenolic waste remediation in aqueous environments.