This technology employs silicone polymers modified with specific functional groups to enhance the viscosity of high-pressure CO2 and hydrocarbon solvents used in oil recovery and hydraulic fracturing. It uses branched polydimethyl siloxane (PDMS) structures terminated with associating groups—such as anthraquinone amide, sulfonamide, and thioxanthone variants—to increase CO2 solubility and promote intermolecular interactions. The formulations demonstrate significant thickening effects when evaluated via high-pressure falling ball viscometry, and they function in a variety of solvent types including hexane, heptane, and aromatic hydrocarbons, despite current reliance on co-solvents and higher concentration levels for optimal performance.
Description
This approach is differentiated by strategically tuning the polymer structure to balance solubility and viscosity enhancement, overcoming earlier failures seen with other thickening agents that were either cost-prohibitive or ineffective. The design leverages low molecular weight PDMS and innovative placement of associating groups, which not only yields lower toxicity and improved compatibility with extraction processes but also offers potential cost efficiencies. Such integration of functionalized silicone chemistry marks a significant advancement in tailoring fluid properties critical for enhanced oil recovery and hydraulic fracturing applications.
Applications
- Enhanced oil recovery
- Hydraulic fracturing additive
- CO2 viscosity modifier
- Supercritical CO2 thickener
Advantages
- Improves viscosity of high-pressure CO2 and hydrocarbon solvents, enhancing oil recovery and hydraulic fracturing efficiency.
- Leverages innovative PDMS-based designs with tailored functional groups to create strong intermolecular interactions.
- Offers a cost-effective and lower-toxicity alternative compared to previous, less reproducible CO2 thickeners.
- Provides versatility across various solvents (e.g., hexane, heptane, aromatic hydrocarbons) and under supercritical CO2 conditions.
- Backed by extensive experimental validation, establishing a strategic framework for future field optimization.
IP Status
https://patents.google.com/patent/US9777122B2
