Phase-Selective Organogelators with pH-Triggered Recovery for Efficient Oil Spill Treatment

Oil spill pollution poses a severe environmental threat, necessitating the development of efficient and sustainable remediation strategies. In this study, we designed and synthesized a series of pH-responsive phase-selective organogelators (pRPSOGs) based on d-gluconic acetal derivatives with long-chain amine groups to selectively solidify oil in oil/water mixtures, facilitating its rapid removal and recovery. The gelation behavior, phase-selective capability, and pH-switchable properties of the synthesized pRPSOGs were systematically investigated by using inversion tests, rheological analysis, Fourier transform infrared spectroscopy, X-ray diffraction, and small-angle X-ray scattering. Molecular simulations were further conducted to elucidate the self-assembly mechanism of the gelators. The optimized gelator, A₁₂, exhibited excellent thermal stability and mechanical strength, ensuring structural integrity during oil spill recovery. Importantly, the pH-responsive property of A₁₂ allowed for reversible solubility modulation, enabling efficient separation and recovery of both the gelator and oil phase without the need for energy-intensive distillation. This innovative strategy provided a reusable, energy-efficient, and environmentally friendly approach for oil spill treatment, offering promising applications for large-scale environmental remediation.