Sequestration of Methylene Blue Dye in a Fixed-Bed Column Using Activated Carbon-Infused Polyurethane Composite Adsorbent Derived from Coconut Oil.

In this research, a new method of treating wastewater is introduced using a highly recyclable and sustainable material derived from coconut oil. This material aims to address the issues commonly faced by conventional sorbents, such as limited performance and costly production. These challenges impede a sorbent material from unlocking its full utility in treating wastewater. An exceptional sorbent material was synthesized by incorporating coconut shell-based activated carbon (AC) into a coconut oil-based polyurethane matrix to produce an activated carbon-infused polyurethane (ACIP). The effective adsorption was elucidated by the synergistic interaction between the ACIP material and methylene blue (MB) through electrostatic attraction, π-π interactions, and hydrogen bonding. To provide an exhaustive analysis of the ACIP material, several analytical techniques were employed, including Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) analysis, X-ray diffraction (XRD) analysis, and thermogravimetric analysis (TGA). A detailed assessment using a fixed-bed column setup investigated its adsorption behavior by encompassing various factors such as inlet concentration, adsorbent bed height, feed flow rate, and solution pH. Results revealed that the ACIP composite exhibited a maximum adsorption capacity of 28.25 mg g⁻¹. Empirical evidence with a high correlation coefficient (R² > 0.93) obtained from the Thomas and Yoon–Nelson model suggests the suitability of the composite material to operate efficiently under these diverse circumstances. Notably, after five consecutive adsorption–desorption cycles, ACIP demonstrated its remarkable reusability by maintaining 86% of its regeneration efficiency. Given its outstanding performance and potential for scalability, this innovative ACIP composite presents a more sustainable approach to addressing wastewater issues within industrial environments. [ABSTRACT FROM AUTHOR]