Extracting and recovering diesel from oil-based drill cuttings using switchable hydrophilic solvents

Switchable hydrophilic solvent (SHS) has been developed as a green extractant for separate lipophilic substances. This article reported an efficient method to extract and recovery diesel in oil-based drill cuttings by using SHS. 1H NMR spectroscopy and pH measurement provided the possibility of SHS can be applied to the recovery of diesel. The screenings of SHS were carried out by CO2 absorption experiments and the solubility of SHS and diesel, which depended on the absorption rate and the solubility parameter model, respectively. The recovery process analyzed the reclaim performance of diesel and DMCHA. The dynamic analysis indicated that the process of DMCHA recovery was consistent with the first-order kinetic, and proved the conclusion of the influence of temperature and aeration rate on DMCHA recovery. Ultimately, the rate constant was used to obtain the DMCHA recovery activation energy of 30.37 kJ mol−1, which provided a reference for the study of low energy consumption. All above studies provided guidance for the design of recycling diesel oil in oil-based drill cuttings by SHS, and therefore, it can achieve the safety and environmental protection of oil-based drill cuttings.