Melamine-based hyper-cross-linked resin for efficient removal of total petroleum hydrocarbons (C₁₀–C₃₂) from aqueous solutions

Petroleum hydrocarbons (PHCs) are produced from industrial discharges, storage leakages, accidental spills, and operational failures. The hazardous nature of PHCs causes serious health risks and threatens the entire aquatic habitat. In this research work, the investigation of the removal of total petroleum hydrocarbons (TPHs) from the contaminated water is carried out utilizing a novel hypercross-linked resin, MAICY, which is generated by condensation of commercially available precursors. The chemical structures of MAICY have been examined extensively by FESEM, FT-IR, solid (CP-MAS) ¹³C-NMR, and TGA. A comprehensive analysis for adsorption parameters of TPHs has been performed, and different models such as Langmuir and Freundlich isotherms have been employed where the Freundlich isotherm was found to be the best fit for removal of THPs (R²= 0.9991). The results revealed that the performance of MAICY for the adsorption of TPHs from contaminated water gives a maximum adsorption capacity (q_e) of 146 mg.g⁻¹. The results of various parameters hinted that the contact time (0.25–4 h), the dosage of adsorbent (0.17 g/L), pH (7), and concentration of TPHs (26.5 mg/L) have controlled the overall adsorptive performance. Moreover, the kinetic data of q_e(expt.) and q_e(calc.) for adsorption of TPHs disclosed the regression values (R²) for pseudo-first order (R²= 0.9921) and pseudo-second order (R²= 0.9891). Additionally, based on CHI factor (X²) error estimations, the data was shown to be more consistent with pseudo-first-order kinetics. Moreover, MAICY demonstrated excellent reusability and recycling properties for up to four consecutive adsorption–desorption cycles. Graphical abstract: (Figure presented.)