Ethylene glycol is an important petrochemical basic organic raw material, mainly used in the production of polyester, antifreeze, membrane, etc. China has abundant coal resources, which makes coal to ethylene glycol technology increasingly valued. As more and more coal to ethylene glycol plants is successfully running in China, the separation problem of ethylene glycol and 1,2-butanediol is urgently waiting to be solved. Selective adsorption is considered the most promising method because of its environmentally friendly characteristic and low cost. In this work, a fixed-bed column was used to separate ethylene glycol and 1,2-butanediol by using CaY zeolite as an absorbent, n-propanol was selected as the best eluent. In the fixed-bed column experiments, breakthrough curves were obtained and the dynamic adsorption characteristics were analyzed through breakthrough curves. The effect of operational conditions, such as flow rate and operating temperature were examined. The adsorption selectivity of ethylene glycol to 1,2-butanediol reached 1.90 at the temperature of 298 K and the flow rate of 0.8 mL/min. It can be found that the adsorption capacity of EG was much higher than 1,2-butanediol. The experiment results indicated that the breakthrough time and adsorption amount both decreased with increase of the flow rate and operating temperature. Modified Dose-Response models gave satisfactory fits to the experimental data of breakthrough curves in a fixed-bed column. At last, the adsorption sites of ethylene glycol and 1,2-butanediol were determined by Grand Canonical Monte Carlo (GCMC) simulation. It was found that the adsorption sites of ethylene and 1,2-butanediol almost overlapped, which meant ethylene glycol and 1,2-butanediol were competitive adsorptions in CaY zeolite. Moreover, the adsorption capacity of ethylene glycol was greater than 1,2-butanediol, which was consistent with the experiment result. The simulation result provided microscopic theoretical support for the experimental results. From these studies, CaY zeolite had the potential to be used as an effective absorbent for the adsorption and separation of ethylene and 1,2-butanediol.