In order to resolve the limitation of the built-in catalyst database in Aspen simulations,a dual-rate kinetic model based on the Power Law (PL) formulation is proposed.The kinetic model is integrated into Aspen Plus for multi-process simulation of hydrogen production.By incorporating the influence of catalysts on the reactions during the simulation,a more realistic chemical process simulation is achieved.The dual-rate kinetic model accurately reflects actual hydrogen production conditions: increasing temperature and reducing liquid hourly space velocity (LHSV) both enhance methanol conversion and simultaneously increase CO selectivity.The steam-to-carbon molar ratio has a minor impact on the reaction.By considering energy consumption,the optimal range of the steam-to-carbon molar ratio is 1.0~1.4.Under the condition in which the reaction temperature is 280 °C and the feed flow rate is 1.5 mL/min,the multi-process simulation results demonstrate that the CO concentration in the product is reduced to only 6.89 μL/L after methanol steam reforming, water-vapor shift,and CO selective oxidation.This CO concentration meets the requirements for proton exchange membrane fuel cells(PEMFC).

Electrochemical reduction of CO₂ to CO using renewable energy is one of the effective ways to achieve "carbon neutrality" and renewable energy storage.This review briefly described the advantages and basic principles of the electrochemical reduction of CO₂ and summarized the research progress of metal electrocatalysts for the electrochemical reduction of CO₂ to CO in aqueous solutions in recent years.Specifically,this study mainly introduced the recent research progress of mono?metal nanocatalysts,bimetallic catalysts,metal?organic complex catalysts,and mono?atom catalysts,which included their influences on the electrochemical reduction of CO₂ and relevant reaction mechanisms.The introduction was conducted from several perspectives,such as the preparation of nanoparticles as well as the regulation of their composition and structure,alloy construction,structural design of metal centers as well as their ligands and carriers,and the development of mono?atom catalysts. In addition, this study summarized the advantages and disadvantages of various catalysts and predicted the development trend of metal catalysts.