There are great energy costs associated with the separation of the light olefins (ethylene and propylene) from mixed hydrocarbon gas feeds. These olefins (obtained from natural gas, biosources, or produced from recycling of waste hydrocarbons) are chemical starting materials for high-demand materials such as PET, PPE, PVC, lubricants and medications. Ionic liquids have been suggested as low energy intensive absorbent materials that could selectively capture and release these gases from mixtures without the need to use the expensive and energy intensive cryogenic distillation. This study aims to provide important contributions towards the understanding of hydrocarbon gas absorption and separations in ionic liquids at a molecular level. In turn this will allow desidesign of absorbents with improved performance leading to the evaluation of their use in an industrial setting.