3D printing of poly(ethyleneimine)-functionalized Mg-Al mixed metal oxide monoliths for direct air capture of CO_(2)  

作　　者：Qingyang Shao Zhuozhen Gan Bingyao Ge Xuyi Liu Chunping Chen Dermot O’Hare Xuancan Zhu 

机构地区：[1]Research Center of Solar Power&Refrigeration,School of Mechanical Engineering,Shanghai Jiao Tong University,Shanghai 200240,China [2]Chemistry Research Laboratory,Department of Chemistry,University of Oxford,Oxford OX13TA,UK

出　　处：《Journal of Energy Chemistry》2024年第9期491-500,共10页能源化学（英文版）

基　　金：supported by the Shanghai Agricultural Science and Technology Program (2022-02-08-00-12-F01176);he National Natural Science Foundation of China (52006135)

摘　　要：Direct air capture(DAC)of CO_(2)plays an indispensable role in achieving carbon-neutral goals as one of the key negative emission technologies.Since large air flows are required to capture the ultradilute CO_(2)from the air,lab-synthesized adsorbents in powder form may cause unacceptable gas pressure drops and poor heat and mass transfer efficiencies.A structured adsorbent is essential for the implementation of gas-solid contactors for cost-and energy-efficient DAC systems.In this study,efficient adsorbent poly(ethyleneimine)(PEI)-functionalized Mg-Al-CO_(3)layered double hydroxide(LDH)-derived mixed metal oxides(MMOs)are three-dimensional(3D)printed into monoliths for the first time with more than 90%adsorbent loadings.The printing process has been optimized by initially printing the LDH powder into monoliths followed by calcination into MMO monoliths.This structure exhibits a 32.7%higher specific surface area and a 46.1%higher pore volume,as compared to the direct printing of the MMO powder into a monolith.After impregnation of PEI,the monolith demonstrates a large adsorption capacity(1.82 mmol/g)and fast kinetics(0.7 mmol/g/h)using a CO_(2)feed gas at 400 ppm at 25℃,one of the highest values among the shaped DAC adsorbents.Smearing of the amino-polymers during the post-printing process affects the diffusion of CO_(2),resulting in slower adsorption kinetics of pre-impregnation monoliths compared to post-impregnation monoliths.The optimal PEI/MeOH ratio for the post-impregnation solution prevents pores clogging that would affect both adsorption capacity and kinetics.

关 键 词：3D printing Mixed metal oxides Amine functionalization Structured adsorbent Direct air capture 

分 类 号：X701[环境科学与工程—环境工程] TP391.73[自动化与计算机技术—计算机应用技术]