[Study of new blended chemical absorbents to absorb CO2].
Three kinds of blended absorbents were investigated on bench-scale experimental bench according to absorption rate and regeneration grade to select a reasonable additive concentration. The results show that, among methyldiethanolamine (MDEA) and piperazine (PZ) mixtures, comparing MDEA : PZ = 1 : 0.4 (m : m) with MDEA : PZ = 1 : 0.2 (m : m), the absorption rate is increased by about 70% at 0.2 mol x mol(-1). When regeneration lasting for 40 min, regeneration grade of blended absorbents with PZ concentration of 0.2, 0.4, and 0.8 is decreased to 83.06%, 77.77% and 76.67% respectively while 91.04% for PZ concentration of 0. MDEA : PZ = 1 : 0.4(m : m) is a suitable ratio for MDEA/PZ mixtures as absorption and regeneration properties of the blended absorbents are all improved. The aqueous blends with 10% primary amines and 2% tertiary amines could keep high CO2 absorption rate, and lower regeneration energy consumption. Adding 2% 2-Amino-2-methyl-1-propanol (AMP) to 10% diethanolamine (DEA), the blended amine solvents have an advantage in absorption and regeneration properties over other DEA/AMP mixtures. Blended solvents, which consist of a mixture of primary amines with a small amount of tertiary amines, have the highest absorption rate among the three. And mixed absorbents of secondary amines and a small amount of sterically hindered amines have the best regeneration property. To combine absorption and regeneration properties, blends with medium activator addition to tertiary amines are competitive.
Wang
Jin-Lian
JL
State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China. wangjinlian_cv@163.com
Fang
Meng-Xiang
MX
Yan
Shui-Ping
SP
Luo
Zhong-Yang
ZY
Cen
Ke-Fa
KF
D000327:Adsorption; D000393:Air Pollutants / Q000737:chemistry / Q000302:isolation & purification*; D000397:Air Pollution / Q000032:analysis / Q000517:prevention & control; D002245:Carbon Dioxide / Q000737:chemistry / Q000302:isolation & purification*; D004983:Ethanolamines / Q000737:chemistry*; D000077489:Piperazine; D010879:Piperazines / Q000737:chemistry*
D000393:Air Pollutants; D004983:Ethanolamines; D010879:Piperazines; D002245:Carbon Dioxide; D000077489:Piperazine; C008430:N-methyldiethanolamine