化工学报 ›› 2022, Vol. 73 ›› Issue (5): 1930-1939.DOI: 10.11949/0438-1157.20211767
殷亚然1(),朱星星1,张先明1,朱春英2,付涛涛2,马友光2()
收稿日期:
2021-12-14
修回日期:
2022-03-02
出版日期:
2022-05-05
发布日期:
2022-05-24
通讯作者:
马友光
作者简介:
殷亚然(1990—),女,博士,讲师,基金资助:
Yaran YIN1(),Xingxing ZHU1,Xianming ZHANG1,Chunying ZHU2,Taotao FU2,Youguang MA2()
Received:
2021-12-14
Revised:
2022-03-02
Online:
2022-05-05
Published:
2022-05-24
Contact:
Youguang MA
摘要:
研究了微通道内醇胺[单乙醇胺(MEA)和甲基二乙醇胺(MDEA)]与离子液体[1-丁基-3-甲基咪唑四氟硼酸([Bmim][BF4])和1-羟乙基-3-甲基咪唑甘氨酸([C2OHmim][GLY])]复配水溶液吸收CO2的传质特性。考察了醇胺/离子液体浓度比(cAA∶cIL)对液相体积传质系数(kLa)的影响,发现kLa随反应速率的增大而增大。为进一步阐释复配水溶液吸收CO2的传质机理,分析了比表面积、扩散速率、增强因子和液弹循环对传质速率的影响。结果表明,四种复配溶液中,反应速率和循环频率(fcir)分别在低流率和高流率下对传质速率起主导作用。kLa可表示为fcir的函数,低气相流率下kLa与fcir呈线性关系,斜率与反应速率成正相关,高气相流率下,液弹循环因膜弹传递困难而对整体传质速率的影响减弱,kLa与fcir呈指数关系,幂律指数小于1。
中图分类号:
殷亚然, 朱星星, 张先明, 朱春英, 付涛涛, 马友光. 微通道内醇胺/离子液体复配水溶液吸收CO2的传质特性[J]. 化工学报, 2022, 73(5): 1930-1939.
Yaran YIN, Xingxing ZHU, Xianming ZHANG, Chunying ZHU, Taotao FU, Youguang MA. Mass transfer characteristics of CO2 absorption in alkanolamine/ionic liquid hybrid aqueous solutions in a microchannel[J]. CIESC Journal, 2022, 73(5): 1930-1939.
溶液 | cAA∶cIL | 密度ρL/(g/cm3) | 黏度ηL/(mPa·s) | 表面张力σ/(mN/m) |
---|---|---|---|---|
MEA/[Bmim][BF4] | 5∶5 | 1.0169 | 1.000 | 37.84 |
6∶4 | 1.0135 | 0.983 | 37.73 | |
7∶3 | 1.0100 | 0.962 | 37.40 | |
8∶2 | 1.0064 | 0.950 | 37.16 | |
9∶1 | 1.0029 | 0.934 | 36.82 | |
10∶0 | 0.9993 | 0.952 | 39.77 | |
MEA/[C2OHmim][GLY] | 5∶5 | 1.0214 | 1.078 | 37.39 |
6∶4 | 1.0170 | 1.041 | 37.90 | |
7∶3 | 1.0125 | 1.008 | 38.45 | |
8∶2 | 1.0082 | 0.964 | 38.95 | |
9∶1 | 1.0037 | 0.930 | 39.45 | |
MDEA/[Bmim][BF4] | 5∶5 | 1.0187 | 1.045 | 35.76 |
6∶4 | 1.0182 | 1.083 | 35.74 | |
7∶3 | 1.0155 | 1.105 | 35.71 | |
8∶2 | 1.0129 | 1.114 | 35.68 | |
9∶1 | 1.0101 | 1.141 | 35.63 | |
10∶0 | 1.0066 | 1.155 | 38.52 | |
MDEA/[C2OHmim][GLY] | 5∶5 | 1.0254 | 1.216 | 37.95 |
6∶4 | 1.0217 | 1.215 | 38.36 | |
7∶3 | 1.0185 | 1.213 | 39.15 | |
8∶2 | 1.0146 | 1.208 | 39.65 | |
9∶1 | 1.0110 | 1.201 | 40.44 |
表1 醇胺/离子液体复配水溶液的物理性质
Table 1 Physical properties of various alkanolamine/ionic liquid aqueous solutions
溶液 | cAA∶cIL | 密度ρL/(g/cm3) | 黏度ηL/(mPa·s) | 表面张力σ/(mN/m) |
---|---|---|---|---|
MEA/[Bmim][BF4] | 5∶5 | 1.0169 | 1.000 | 37.84 |
6∶4 | 1.0135 | 0.983 | 37.73 | |
7∶3 | 1.0100 | 0.962 | 37.40 | |
8∶2 | 1.0064 | 0.950 | 37.16 | |
9∶1 | 1.0029 | 0.934 | 36.82 | |
10∶0 | 0.9993 | 0.952 | 39.77 | |
MEA/[C2OHmim][GLY] | 5∶5 | 1.0214 | 1.078 | 37.39 |
6∶4 | 1.0170 | 1.041 | 37.90 | |
7∶3 | 1.0125 | 1.008 | 38.45 | |
8∶2 | 1.0082 | 0.964 | 38.95 | |
9∶1 | 1.0037 | 0.930 | 39.45 | |
MDEA/[Bmim][BF4] | 5∶5 | 1.0187 | 1.045 | 35.76 |
6∶4 | 1.0182 | 1.083 | 35.74 | |
7∶3 | 1.0155 | 1.105 | 35.71 | |
8∶2 | 1.0129 | 1.114 | 35.68 | |
9∶1 | 1.0101 | 1.141 | 35.63 | |
10∶0 | 1.0066 | 1.155 | 38.52 | |
MDEA/[C2OHmim][GLY] | 5∶5 | 1.0254 | 1.216 | 37.95 |
6∶4 | 1.0217 | 1.215 | 38.36 | |
7∶3 | 1.0185 | 1.213 | 39.15 | |
8∶2 | 1.0146 | 1.208 | 39.65 | |
9∶1 | 1.0110 | 1.201 | 40.44 |
图4 液相浓度比对液相体积传质系数(kLa)的影响
Fig.4 Effects of concentration ratio of alkanolamine to ionic liquid on the liquid-phase volumetric mass transfer coefficient (kLa)
cAA∶cIL | MEA/ [Bmim][BF4] | MEA/ [C2OHmim][GLY] | MDEA/[Bmim][BF4] | MDEA/ [C2OHmim][GLY] | ||||
---|---|---|---|---|---|---|---|---|
α | β | α | β | α | β | α | β | |
5∶5 | 0.029 | 3.692 | 0.057 | 5.320 | 0.019 | 1.140 | 0.041 | 4.336 |
6∶4 | 0.034 | 3.740 | 0.059 | 5.111 | 0.017 | 1.692 | 0.041 | 3.561 |
7∶3 | 0.043 | 3.776 | 0.063 | 4.677 | 0.019 | 1.662 | 0.033 | 3.519 |
8∶2 | 0.047 | 3.636 | 0.058 | 4.917 | 0.022 | 1.306 | 0.031 | 3.067 |
9∶1 | 0.050 | 4.191 | 0.060 | 4.962 | 0.023 | 1.256 | 0.027 | 2.582 |
10∶0 | 0.059 | 4.292 | 0.059 | 4.292 | 0.022 | 1.459 | 0.020 | 1.693 |
表2 不同复配溶液的拟合系数α和β
Table 2 Coefficients α and β for different alkanolamine/ionic liquid solutions
cAA∶cIL | MEA/ [Bmim][BF4] | MEA/ [C2OHmim][GLY] | MDEA/[Bmim][BF4] | MDEA/ [C2OHmim][GLY] | ||||
---|---|---|---|---|---|---|---|---|
α | β | α | β | α | β | α | β | |
5∶5 | 0.029 | 3.692 | 0.057 | 5.320 | 0.019 | 1.140 | 0.041 | 4.336 |
6∶4 | 0.034 | 3.740 | 0.059 | 5.111 | 0.017 | 1.692 | 0.041 | 3.561 |
7∶3 | 0.043 | 3.776 | 0.063 | 4.677 | 0.019 | 1.662 | 0.033 | 3.519 |
8∶2 | 0.047 | 3.636 | 0.058 | 4.917 | 0.022 | 1.306 | 0.031 | 3.067 |
9∶1 | 0.050 | 4.191 | 0.060 | 4.962 | 0.023 | 1.256 | 0.027 | 2.582 |
10∶0 | 0.059 | 4.292 | 0.059 | 4.292 | 0.022 | 1.459 | 0.020 | 1.693 |
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