Biogas Upgrading via Cyclic CO2Adsorption: Application of Highly Regenerable PEI@nano-Al2O3Adsorbents with Anti-Urea Properties

Shen，Xuehua1,2; Yan，Feng1,3; Li，Chunyan1; Qu，Fan1; Wang，Yingqing1; Zhang，Zuotai1,3

2021

10.1021/acs.est.0c07973

ENVIRONMENTAL SCIENCE & TECHNOLOGY   影响因子和分区

0013-936X

1520-5851

Solid amine adsorbents are among the most promising CO2 adsorption technologies for biogas upgrading due to their high selectivity toward CO2, low energy consumption, and easy regeneration. However, in most cases, these adsorbents undergo severe chemical inactivation due to urea formation when regenerated under a realistic CO2 atmosphere. Herein, we demonstrated a facile and efficient synthesis route, involving the synthesis of nano-Al2O3 support derived from coal fly ash with a CO2 flow as the precipitant and the preparation of polyethylenimine (PEI)-impregnated Al2O3-supported adsorbent. The optimal 55%PEI@2%Al2O3 adsorbent showed a high CO2 uptake of 139 mg·g-1 owing to the superior pore structure of synthesized nano-Al2O3 support and exhibited stable cyclic stability with a mere 0.29% decay per cycle even under the realistic regenerated CO2 atmosphere. The stabilizing mechanism of PEI@nano-Al2O3 adsorbent was systematically demonstrated, namely, the cross-linking reaction between the amidogen of a PEI molecule and nano-Al2O3 support, owing to the abundant Lewis acid sites of nano-Al2O3. This cross-linking process promoted the conversion of primary amines into secondary amines in the PEI molecule and thus significantly enhanced the cyclic stability of PEI@nano-Al2O3 adsorbents by markedly inhibiting the formation of urea compounds. Therefore, this facile and efficient strategy for PEI@nano-Al2O3 adsorbents with anti-urea properties, which can avoid active amine content dilution from PEI chemical modification, is promising for practical biogas upgrading and various CO2 separation processes.

SCI ; EI

英语

NI论文

第一 ; 通讯

National Natural Science Foundation of China[22008104,51772141,52006096] ; National Key R&D Program of China[2018YFC1902904] ; Shenzhen Science and Technology Innovation Committee["J20200109141642225","J20200109141437586","KQJSCX20180322151507786"] ; Shenzhen Peacock Plan[KQTD20160226195840229]

Engineering ; Environmental Sciences & Ecology

Engineering, Environmental ; Environmental Sciences

WOS:000643546400102

AMER CHEMICAL SOC

20211810291626

Alumina ; Amines ; Biogas ; Carbon dioxide ; Chemical modification ; Coal industry ; Crosslinking ; Energy utilization ; Fly ash ; Metabolism ; Molecules ; Pore structure ; Urea

Mines and Mining, Coal:503 ; Gas Fuels:522 ; Solid Fuels:524 ; Energy Utilization:525.3 ; Chemical Reactions:802.2 ; Organic Compounds:804.1 ; Inorganic Compounds:804.2 ; Physical Properties of Gases, Liquids and Solids:931.2 ; Atomic and Molecular Physics:931.3

ENVIRONMENT/ECOLOGY

2-s2.0-85104923753

Scopus

1.School of Environmental Science and Engineering,Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control,Southern University of Science and Technology,Shenzhen,518055,China
2.School of Environment,Harbin Institute of Technology,Harbin,150090,China
3.Key Laboratory of Municipal Solid Waste Recycling Technology and Management of Shenzhen City,Shenzhen,518055,China

Shen，Xuehua,Yan，Feng,Li，Chunyan,et al. Biogas Upgrading via Cyclic CO2Adsorption: Application of Highly Regenerable PEI@nano-Al2O3Adsorbents with Anti-Urea Properties[J]. ENVIRONMENTAL SCIENCE & TECHNOLOGY,2021,55(8):5236-5247.

Shen，Xuehua,Yan，Feng,Li，Chunyan,Qu，Fan,Wang，Yingqing,&Zhang，Zuotai.(2021).Biogas Upgrading via Cyclic CO2Adsorption: Application of Highly Regenerable PEI@nano-Al2O3Adsorbents with Anti-Urea Properties.ENVIRONMENTAL SCIENCE & TECHNOLOGY,55(8),5236-5247.

Shen，Xuehua,et al."Biogas Upgrading via Cyclic CO2Adsorption: Application of Highly Regenerable PEI@nano-Al2O3Adsorbents with Anti-Urea Properties".ENVIRONMENTAL SCIENCE & TECHNOLOGY 55.8(2021):5236-5247.