We have examined the performance of phosphorene-based material, phosphorene slit pores (PSP), in CO2 adsorption and separation from natural gas by using Density Function Theory (DFT) calculation and Grand Canonical Monte Carlo (GCMC) simulations. First, the adsorption of CH4 and CO2 molecules on phosphorene sheet were conducted by DFT study. Then, adsorption performances of natural gas components as well as their binary CO2/CH4 gas mixture were investigated at 300 K with the pressure up to 3.0 MPa. The effects of slit pore width, H, and mole ratio of CO2/CH4 in the gas phase on the separation of CO2 from mixtures of CO2/CH4 were also investigated. Our DFT calculation results show that the CO2 moleculehas higher adsorption energy than that of CH4, which implies that it can be easily adsorbed to the phosphorene surface than CH4. Detailed.GCMC simulations reveal that the phosphorene slit pore has a high performance in separating CO2 from nature gas and achieves the highest gas selectivity at H = 1.0 nm at pressures lower than 0.1 MPa. Moreover, the selectivity of CO2 over CO2/CH4 gas mixture increases with increasing the mole ratio of CO2/CH4 due to the enhanced adsorbate-adsorbent interactions for the favorable component. Therefore, it is suggested that the phosphorene is a promising candidate for natural gas purification and possessing practical potential applications in gas adsorption. (C) 2016 Elsevier B.V. All rights reserved.