Higher Fatty Acid-Based CO₂-Controllable Dual-Circulation Approach for Oil Recovery

Abstract

In this article, a higher fatty acid-based ternary CO2-controllable dual-circulation had been successfully constructed, where it provided an excellent oil recovery performance and all solvents could be cycled. This dual-circulation adopted the oil-soluble higher fatty acid (HFA) as the outside loop to extract oil and selected poly­(propylene glycol) bis­(2-aminopropylether) (Jeffamine D230) as the inner loop to impel the outside loop. In washing oil technology, D230 and HFA as cleaning solvents are ideal substitutes for traditional tertiary amines. First, there is the electrostatic interaction between HFA (represented by n-decanoic acid) and D230, as detected by 1H MNR. The circulation of the system is supported by the rapid CO2-switchable behaviors of HFA-D230, where the reversible phenomenon was recorded by a pH meter and a conductivity meter. In addition, the HFA/D230/water system has demonstrated the cyclic process of dissolving the oil in the simulated oil (the dodecane, kerosene, and diesel) recovery experiment. Finally, the n-decanoic acid (C10-HFA)/D230/water ternary dual-circulation system was obtained as the optimal scheme due to its excellent recovery and separation property. During the separation of simulated oil by using the C10-HFA/D230/water system, the recovery rate of the simulated oil was more than 93% and there was no residual n-decanoic acid by GC/MS analysis. This dual-circulation was successfully established, providing a new method to replace the traditional tertiary amine for oil recovery.

Temperature-Responsive Deep Eutectic Solvents for Highly Selective Separation of 5-Hydroxymethylfurfural from Reaction Mixture

“…At this stage, HMF was transferred to the DES-rich phase, while the unreacted fructose was retained in the H 2 O-rich phase, and then selective separation of HMF was achieved (Figure c). More importantly, HMF can be recovered from the DES-rich phase by the addition of diethylamine (Figure d), , while DES can be easily regenerated by bubbling CO 2 because of the salting-out effect of ammonium salt generated by the reaction between CO 2 and diethylamine (Figure e) . In addition, diethylamine could be regenerated by ammonium salt through bubbling N 2 and heating and then reused in the next run. , …”

CO2-Repurification Microemulsion Detergent for Oil-Based Slurry Cleaning

“…Interestingly, in recent years, a new class of solvents is regulated by an intelligent solvent sensitive to external stimuli, such as pH, light, temperature, and CO 2 , − to achieve reversible transformation of its physical properties, which covers the reversible change of emulsion emulsification and demulsification . If the molecules with switching characteristics are selected in the preparation design of surfactants and the appropriate ratio is studied, the use of demulsifiers can be avoided.…”

Amine-free CO2-switchable hydrophilicity solvents and their application in extractions and polymer recycling

“…1), we call this an anionic SHS (ASHS). 58,65 Sed et al later reported that using a mixture of two acids, rather than a single acid, could lower the melting point and viscosity of the SHS, resulting in a wider operating temperature range and better transport properties for extraction processes (higher mass transfer coefficient, etc.). 61 An ASHS is similar in many ways to a CSHS, but the use of carboxylic acids changes the chemistry taking place.…”