Abstract: Under the background of peaking carbon dioxide emissions and carbon neutral strategy, the traditional chemical industry needs to seek a trade-off between economic benefits and environmental impacts. As a typical ethylene production unit, the high and low pressure deethanization process has problems with variable feed composition, timely adjustment of process parameters, and conflicts between precise material separation and high energy consumption. To address this issue, a multi-objective optimization framework is proposed to achieve the optimum of the two objectives. First, based on the Aspen Plus platform, a process model for dual tower deethanization is constructed, and the Pareto frontier with dual objectives of environmental and economic benefits is obtained by the non-dominated sorting genetic algorithm II (NSGA-II) based on stipulations including product quality constraints and the maximum allowable operating range of the process. Furthermore, the TOPSIS (Technique for Order Preference by Similarity to an Ideal Solution) method of multi-objective decision analysis criterion is further used to obtain the optimal operating point on the Pareto frontier. Finally, univariate analysis is used to investigate the effects of heat exchanger temperature, tower kettle heat duty, cracking unit outlet temperature, and return flow rate on the objective function. Compared with actual plant operating conditions, the optimized plan reduces CO₂ emissions by 8.45% at the expense of 0.91% of pre-tax profit, with the potential to achieve the best economic benefits and environmental impact.