**Abstract**

In oil fields CO2-EOR have extravagant interest because of its increasing microscopic sweep efficiency. As a balance and dense solution over a huge range of temperature and pressure, carbon dioxide can improve viscosity reduction and oil swelling because of all partial miscibility with heavy oils and proportion miscibility with light oils, and also carbon dioxide has mutual solubility with water and hydrocarbons that these properties result in increasing microscopic sweep efficiency in mechanism of CO2 injection. However, due to CO2 lower viscosity than water and oil, CO2-EOR efficiency is limited that causes near well-bore conformance issue and mobility contrast problem such as gravity override and fingering. The carbon dioxide philic surfactant blends traditionally includes foam booster, foam stabiliser and foaming surfactant. An integrated propertyperformance analysis of blends of anionic surfactants includes carbon dioxide philic groups such as twin-tailed carbonyl group, propylene-oxide and methyl group of CO2 philic groups under the circumstances of reservoir showed that carbon dioxide philic surfactants can be the mixture of CO2 problems. Here we will underline that modifying the surfactant tail can be a proper path to surpass foaming performance.

**Keywords:** EOR, foam, CO2-philic surfactants
