In this work,a series of polyethyleneimine (PEI) functionalized commercial silica gel were prepared by wet impregnation method and used as CO2 sorbent.The as-prepared sorbents were characterized by N2 adsorption,FT-IR and SEM techniques.CO2 capture was tested in a fixed bed reactor using a simulated flue gas containing 15.1％ CO2 in a temperature range of 25-100 ℃.The effects of sorption temperature and amine content on CO2 uptake of the adsorbents were investigated.The silica gel with a 30 wt％ PEI loading manifested the largest CO2 uptake of 93.4 mgCO2/gadsorbent (equal to 311.3 mgCO2/gPEI) among the tested sorbents under the conditions of 15.1％ (v/v) CO2 in N2 at 75 ℃ and atmospheric pressure.Moreover,it was rather low-cost.In addition,the PEI-impregnated silica gel exhibited stable adsorption-desorption behavior during 5 consecutive test cycles.These results suggest that the PEI-impregnated silica gel is a promising and cost-effective sorbent for CO2 capture from flue gas and other stationary sources with low CO2 concentration.