Supporting Information Enhanced Dynamic CO2 Adsorption Capacity ...
Supporting Information Enhanced Dynamic CO2 Adsorption Capacity and CO2/CH4 Selectivity on Polyethyleneimine Impregnated UiO-66 Shikai Xiana, Ying Wua, Junliang Wub, Xun Wangb，Jing Xiaoa*
a.
School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510640, China
b. School of Environment and Energy, Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control,, South China University of Technology, Guangzhou, 510640, China
E-mail: [email protected] (Jing Xiao)
S1
List of Contents S1. Synthesis of UiO-66 S2. Fixed-bed Adsorption Experiments S3. Calculation of Working Capacity S4. Calculation of Dynamic CO2/CH4 Adsorption Selectivity Figures: S1-S8 Tables: S1 References
S1. Synthesis of UiO-66. UiO-66 was synthesized by a hydrothermal method1 following the procedures as: ZrCl4 and terephthalic acid were mixed at the ratio of 1:1 at room temperature, and then added into 50 ml DMF. About 2.5 ml HCl (36.5 wt%) was added into the above slurry drop by drop under ultrasonic for 20 min to fully dissolve the mixture. The mixture was then heated to 353 K and retained at 353 K for 12 h. After that, the solution was cooled down to room temperate, and the obtained precipitation was washed with DMF for 4 times in 3 days and the such-prepared UiO-66 was activated under vacuum at 423 K for 8 h, and then sealed in a desiccator before use.
S2
S2. Fixed-bed Adsorption Experiments Fig. S1 showed the self-assembly experimental setup. This apparatus consisted of three parts, an adiabatic sorption column, a gaseous mixture system for controlling the composition, relative humidity and temperature of gaseous mixture, and on-line gas mass spectrometer analysis. The temperature of adsorption column could be adjusted and maintained at a constant value with an accuracy of ±0.5 K. The relative humidity (RH) could be adjusted and controlled to a precision of ±3%.
In fixed bed breakthrough experiments, the water vapor was generated by using a water bubbler. 100 mg of adsorbent was packed in the adsorption column (I.D. 0.8cm * L. 5cm). The composition of gaseous mixture was adjusted and controlled by mass flow controller which simultaneously controls flowrates of three kinds of gases such as CO2, CH4, and N2. The outlet gas composition was determined by using an on-line mass spectrometer (HIDEN QIC-20, Beijing, China). The breakthrough curves of CO2/CH4 binary mixture (10/90, v/v) through the fixed bed of PEI@UiO-66 samples separately at different temperatures (308 K, 318 K, 328 K, 338K and 348K) and 1 bar were measured. In addition, the breakthrough curves of CO2/N2/H2O ternary mixture at 1 bar and different temperatures under varied relative humidity (0%, 30%, and 55%) were measured separately.
S3
Figure S1. The self-assembly fixed-bed experimental setup. 1. CO2/CH4; 2. N2; 3.He; 4. CO2/CH4; 5. Mass flow controller; 6. Mass flowmeter; 7.Water bubler; 8 & 9. Gases mixer; 10. Bypass valve; 11. Hygrometer; 12. Adsorption column; 13. Mass spectrometer.
S3.
Calculation of Working Capacity
According to breakthrough curves of binary or ternary gaseous mixture, the working adsorption capacity of an adsorbent in packed bed was calculated using the following equation2:
qi =
Ci p mads RT
mads Vt − Vcol + ρ ads
(1)
Where qi is the working adsorption capacity of the component i, Ci is the gas phase concentration, mads is the adsorbent mass, T is the experiment temperature, V is the total volumetric flow rate, Vcol is the column volume, and ρads is the adsorbent grain S4
density, and t is the dynamic adsorption time, which can be calculated using the following equation: C t = ∫ 1 − t Ci
Where
(2)
dt
Ct is the outlet concentration of gas component i at the time t.
S4. Calculation of dynamic CO2/CH4 adsorption selectivity CO2/CH4
dynamic adsorption selectivity (S) of an adsorbent can be found out on
the basis of experimental breakthrough curves by using the following equation:
Si , j =
qi / q j Xi / X j
(3)
Where q and X are the adsorbed amounts and molar fractions in the bulk phase of the components i and j, respectively3-5.
S5
Figures
Figure S2. FTIR spectrum of PEI
Figure S3. PXRD patterns of UiO-66 and PEI@UiO-66s S6
Figure S4. The CO2 adsorption isotherms of PEI@UiO-66s (surface area-basis) with different PEI loading at 298 K
Figure S5. The fitted DSL isotherm curves of CO2 on UiO-66 and PEI@UiO-66s
S7
Figure S6. Breakthrough curves of CO2/CH4 over 30% PEI@UiO-66 from binary CO2/CH4 mixture (vCO2/vCH4 of 1/9) at 318 K
Figure S7. Breakthrough curves of CO2/CH4 over 30% PEI@UiO-66 from binary CO2/CH4 mixture (vCO2/vCH4 of 1/9) at 328 K S8
Figure S8. Breakthrough curves of CO2/CH4 binary mixture (vCO2/vCH4 of 1/9) over UiO-66 at 308 K and under different relative humidities
Tables Table S1. The parameters from the fitted DSL isotherm curves of CO2 on UiO-66 and PEI@UiO-66s Adsorbent
q1
b1
q2
d2
R2
UiO-66
1.463
0.0126
72.940
1.7583E-4
0.99994
10PEI@UiO-66
0.698
0.653
7.621
0.00299
0.99999
20PEI@UiO-66
0.833
0.477
8.124
0.00307
0.99986
30PEI@UiO-66
1.056
0.395
5.558
0.00307
0.99945
40PEI@UiO-66
1.253
2.345
1.578
0.0115
0.99991
S9
Reference 1.
Kandiah, M.; Nilsen, M. H.; Usseglio, S.; Jakobsen, S.; Olsbye, U.; Tilset, M.;
Larabi, C.; Quadrelli, E. A.; Bonino, F.; Lillerud, K. P., Synthesis and Stability of Tagged UiO-66 Zr-MOFs. Chem. Mater. 2010, 22, 6632-6640. 2.
García, E. J.; Mowat, J. P. S.; Wright, P. A.; Pérez-Pellitero, J.; Jallut, C.;
Pirngruber, G. D., Role of Structure and Chemistry in Controlling Separations of CO2/CH4 and CO2/CH4/CO Mixtures over Honeycomb MOFs with Coordinatively Unsaturated Metal Sites. J. Phys. Chem. C 2012, 116, 26636-26648. 3.
Ho, M. T.; Allinson, G. W.; Wiley, D. E., Reducing the Cost of CO2 Capture from
Flue Gases Using Pressure Swing Adsorption. Ind. Eng. Chem. Res. 2008, 47, 4883-4890. 4.
Krishna, R.; van Baten, J. M., A comparison of the CO2 capture characteristics of
zeolites and metal organic frameworks. Sep. Pur. Technol. 2012, 87, 120-126. 5.
Hamon, L.; Jolimaître, E.; Pirngruber, G. D., CO2 and CH4 Separation by
Adsorption Using Cu-BTC Metal-Organic Framework. Ind. Eng. Chem. Res. 2010, 49, 7497-7503.
S10
a.
School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510640, China
b. School of Environment and Energy, Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control,, South China University of Technology, Guangzhou, 510640, China
E-mail: [email protected] (Jing Xiao)
S1
List of Contents S1. Synthesis of UiO-66 S2. Fixed-bed Adsorption Experiments S3. Calculation of Working Capacity S4. Calculation of Dynamic CO2/CH4 Adsorption Selectivity Figures: S1-S8 Tables: S1 References
S1. Synthesis of UiO-66. UiO-66 was synthesized by a hydrothermal method1 following the procedures as: ZrCl4 and terephthalic acid were mixed at the ratio of 1:1 at room temperature, and then added into 50 ml DMF. About 2.5 ml HCl (36.5 wt%) was added into the above slurry drop by drop under ultrasonic for 20 min to fully dissolve the mixture. The mixture was then heated to 353 K and retained at 353 K for 12 h. After that, the solution was cooled down to room temperate, and the obtained precipitation was washed with DMF for 4 times in 3 days and the such-prepared UiO-66 was activated under vacuum at 423 K for 8 h, and then sealed in a desiccator before use.
S2
S2. Fixed-bed Adsorption Experiments Fig. S1 showed the self-assembly experimental setup. This apparatus consisted of three parts, an adiabatic sorption column, a gaseous mixture system for controlling the composition, relative humidity and temperature of gaseous mixture, and on-line gas mass spectrometer analysis. The temperature of adsorption column could be adjusted and maintained at a constant value with an accuracy of ±0.5 K. The relative humidity (RH) could be adjusted and controlled to a precision of ±3%.
In fixed bed breakthrough experiments, the water vapor was generated by using a water bubbler. 100 mg of adsorbent was packed in the adsorption column (I.D. 0.8cm * L. 5cm). The composition of gaseous mixture was adjusted and controlled by mass flow controller which simultaneously controls flowrates of three kinds of gases such as CO2, CH4, and N2. The outlet gas composition was determined by using an on-line mass spectrometer (HIDEN QIC-20, Beijing, China). The breakthrough curves of CO2/CH4 binary mixture (10/90, v/v) through the fixed bed of PEI@UiO-66 samples separately at different temperatures (308 K, 318 K, 328 K, 338K and 348K) and 1 bar were measured. In addition, the breakthrough curves of CO2/N2/H2O ternary mixture at 1 bar and different temperatures under varied relative humidity (0%, 30%, and 55%) were measured separately.
S3
Figure S1. The self-assembly fixed-bed experimental setup. 1. CO2/CH4; 2. N2; 3.He; 4. CO2/CH4; 5. Mass flow controller; 6. Mass flowmeter; 7.Water bubler; 8 & 9. Gases mixer; 10. Bypass valve; 11. Hygrometer; 12. Adsorption column; 13. Mass spectrometer.
S3.
Calculation of Working Capacity
According to breakthrough curves of binary or ternary gaseous mixture, the working adsorption capacity of an adsorbent in packed bed was calculated using the following equation2:
qi =
Ci p mads RT
mads Vt − Vcol + ρ ads
(1)
Where qi is the working adsorption capacity of the component i, Ci is the gas phase concentration, mads is the adsorbent mass, T is the experiment temperature, V is the total volumetric flow rate, Vcol is the column volume, and ρads is the adsorbent grain S4
density, and t is the dynamic adsorption time, which can be calculated using the following equation: C t = ∫ 1 − t Ci
Where
(2)
dt
Ct is the outlet concentration of gas component i at the time t.
S4. Calculation of dynamic CO2/CH4 adsorption selectivity CO2/CH4
dynamic adsorption selectivity (S) of an adsorbent can be found out on
the basis of experimental breakthrough curves by using the following equation:
Si , j =
qi / q j Xi / X j
(3)
Where q and X are the adsorbed amounts and molar fractions in the bulk phase of the components i and j, respectively3-5.
S5
Figures
Figure S2. FTIR spectrum of PEI
Figure S3. PXRD patterns of UiO-66 and PEI@UiO-66s S6
Figure S4. The CO2 adsorption isotherms of PEI@UiO-66s (surface area-basis) with different PEI loading at 298 K
Figure S5. The fitted DSL isotherm curves of CO2 on UiO-66 and PEI@UiO-66s
S7
Figure S6. Breakthrough curves of CO2/CH4 over 30% PEI@UiO-66 from binary CO2/CH4 mixture (vCO2/vCH4 of 1/9) at 318 K
Figure S7. Breakthrough curves of CO2/CH4 over 30% PEI@UiO-66 from binary CO2/CH4 mixture (vCO2/vCH4 of 1/9) at 328 K S8
Figure S8. Breakthrough curves of CO2/CH4 binary mixture (vCO2/vCH4 of 1/9) over UiO-66 at 308 K and under different relative humidities
Tables Table S1. The parameters from the fitted DSL isotherm curves of CO2 on UiO-66 and PEI@UiO-66s Adsorbent
q1
b1
q2
d2
R2
UiO-66
1.463
0.0126
72.940
1.7583E-4
0.99994
10PEI@UiO-66
0.698
0.653
7.621
0.00299
0.99999
20PEI@UiO-66
0.833
0.477
8.124
0.00307
0.99986
30PEI@UiO-66
1.056
0.395
5.558
0.00307
0.99945
40PEI@UiO-66
1.253
2.345
1.578
0.0115
0.99991
S9
Reference 1.
Kandiah, M.; Nilsen, M. H.; Usseglio, S.; Jakobsen, S.; Olsbye, U.; Tilset, M.;
Larabi, C.; Quadrelli, E. A.; Bonino, F.; Lillerud, K. P., Synthesis and Stability of Tagged UiO-66 Zr-MOFs. Chem. Mater. 2010, 22, 6632-6640. 2.
García, E. J.; Mowat, J. P. S.; Wright, P. A.; Pérez-Pellitero, J.; Jallut, C.;
Pirngruber, G. D., Role of Structure and Chemistry in Controlling Separations of CO2/CH4 and CO2/CH4/CO Mixtures over Honeycomb MOFs with Coordinatively Unsaturated Metal Sites. J. Phys. Chem. C 2012, 116, 26636-26648. 3.
Ho, M. T.; Allinson, G. W.; Wiley, D. E., Reducing the Cost of CO2 Capture from
Flue Gases Using Pressure Swing Adsorption. Ind. Eng. Chem. Res. 2008, 47, 4883-4890. 4.
Krishna, R.; van Baten, J. M., A comparison of the CO2 capture characteristics of
zeolites and metal organic frameworks. Sep. Pur. Technol. 2012, 87, 120-126. 5.
Hamon, L.; Jolimaître, E.; Pirngruber, G. D., CO2 and CH4 Separation by
Adsorption Using Cu-BTC Metal-Organic Framework. Ind. Eng. Chem. Res. 2010, 49, 7497-7503.
S10
