Adsorption Species Distribution and Multicomponent Adsorption

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Adsorption species distribution and multi-component adsorption mechanism of SO2, NO and CO2 on commercial adsorbents Lei Luo, Yangyang Guo, Tingyu Zhu, and Yang Zheng Energy Fuels, Just Accepted Manuscript • DOI: 10.1021/acs.energyfuels.7b01422 • Publication Date (Web): 11 Sep 2017 Downloaded from http://pubs.acs.org on September 12, 2017

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Adsorption species distribution and multi-component adsorption mechanism of SO2, NO and CO2 on commercial adsorbents Lei Luo1, 3, Yangyang Guo1*, Tingyu Zhu1, 2*, Yang Zheng1

(1Beijing Engineering Research Center of Process Pollution Control, National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China 2

Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment,

Chinese Academy of Sciences, Xiamen 361021, China) 3

School of Chemistry and Chemical Engineering, Guizhou University, Guiyang 550025, China）

Submitted to

Energy & Fuels

12 August, 2017

1

ACS Paragon Plus Environment

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Adsorption species distribution and multi-component adsorption mechanism of SO2, NO and CO2 on commercial adsorbents Lei Luo1, 3, Yangyang Guo1*, Tingyu Zhu1, 2*, Yang Zheng1

1

Beijing Engineering Research Center of Process Pollution Control, National Engineering

Laboratory for Hydrometallurgical Cleaner Production Technology, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China 2

Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment,

Chinese Academy of Sciences, Xiamen 361021, China 3

School of Chemistry and Chemical Engineering, Guizhou University, Guiyang 550025, China

*

Corresponding author

Tel: +86-10-82544821

Fax: +86-10-82544822

Email address: [email protected](Y. Guo), [email protected](T. Zhu)

ABSTRACT: Adsorption is a commonly used method for gas pollutant removal, the adsorption performances of four commercial adsorbents have been compared in this work through a ﬁxed-bed reactor. The single gas adsorption results show that zeolite is more effective for SO2, NO and CO2 removal among the four adsorbents. SO2, NO and CO2 are mainly monolayer adsorbed on adsorbents. Physically adsorbed SO2 is the main adsorption species on 13X zeolite, 5A zeolite and mesoporous alumina according to TPD-MS, while SO2 is more easily oxidized on activated carbon than the 2


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other adsorbents; NO can be oxidized more easily on zeolite than activated carbon , only physically adsorbed CO2 is detected on these adsorbents. Multi-component adsorption is investigated on 13X zeolite and activated carbon. For gas adsorption on 13X zeolite, the inhibitive effect of NO on SO2 is 26.3% higher than that of CO2 on SO2, indicating that NO plays a dominant role in SO2 adsorption. Physically adsorbed NO is the only NO adsorption species on 13X when SO2 exists, showing NO oxidation on 13X is greatly inhibited by SO2. For gas adsorption on activated carbon, chemically adsorbed SO2 increases largely after NO put in, showing the promotive effect of NO on SO2 is mainly for the chemically adsorbed SO2. In the presence of SO2, chemically adsorbed NO almost disappeared, which indicates that SO2 mainly dominate chemically adsorbed NO on activated carbon. The effects of adsorbent performance on multi-component gas adsorption is reflected by gas adsorption mechanism. These findings provide considerable specific information for industrial flue gas purification. Key words: SO2, NO and CO2; industrial flue gas; adsorbents properties; multi-component adsorption; TPD-MS

1. INTRODUCTION China is a huge coal consuming country with nearly three billion tons of raw coal consumed annually.1 Consequently, many pollutants have been emitted due to the coal combustion; 87% of SO2, 67% of NOx and 71% of CO2 are released from coal combustion.2,3 Much stricter legislations and standards have been published to limit these gas pollutants, for the pollutants may cause serious environmental and climate 3


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problems.4 Adsorption is a commonly used method for gas pollutants removal. Varieties of adsorbents have been adopted, such as activated carbon (AC), zeolite, silicone, and mesoporous alumina (MA) et. al.5-8 The properties of the adsorbents greatly affect gas adsorption behaviour according to the previous studies. AC is widely used due to its large specific surface area and pore volume, its textural characteristics affect gas adsorption behaviour greatly, for instance, CO2 adsorption amount increased from 61.6 mg/g to 132.8 mg/g after the BET surface area increased from 390 m2/g to 669 m2/g.9 Gas adsorption may be also affected by the functional groups, it has been verified that the amount of chemically adsorbed SO2 on AC is more than the physically adsorbed SO2, for the existence of oxygen groups on AC.10 The polarizability of zeolite shows obvious superiority on polar molecule adsorption, the SO2 adsorption amount on Y-zeolite is more than 50 mg/g at 373 K.11 In addition, the Si/Al ratio of zeolites is an important factor for gas adsorption, compared with higher Si/Al ratio of clinoptilolite zeolite at 5.26 and 4.34, the chabazite zeolite with a Si/Al ratio of 3.12 shows the highest CO2 adsorption amount of 114 mg/g.12 Accordingly, appropriate adsorbents modification can enhance gas adsorption, the ammonia-treated AC promotes N2, H2 and CO2 adsorption amounts by 10%, 28% and 19%, respectively,13 furthermore chemically adsorbed gases is promoted by amine modification.14 Similarly, ammonium hydroxide treated MA could improve CO2 adsorption by the increase of adsorbent basicity,15 CO2 adsorption amount increased by about 17% on Li+ modified H-SSZ-13/12 zeolite.16 4


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Gas components also have impacts on adsorption, while the components influence on each other may vary with different adsorbents. The co-adsorption of SO2 and NO on AC are extensively investigated, SO2 inhibits NO adsorption while NO promotes SO2 adsorption. According to the adsorption species detected by thermal desorption, chemically adsorbed SO2 and NO sites on AC are the same, the stronger attachment between SO2 and AC decreases NO adsorption.17 For the SO2 and NO co-adsorption on MA, SO2 promotes NO oxidation and NO promotes SO2 oxidation due to the formation of intermediates [SO3NO] or [SO3NO2].18 The co-adsorption of SO2 and NO on zeolite are analogous to MA, SO2 and NO adsorption amount decreased 5.3% and 15.3% after CO2 added; however, this inhibition mechanism and adsorption products are not been clearly demonstrated.19 In summary, adsorbent properties affect single gas adsorption as well as the multi-component adsorption. Most of the previous research work has focused on SO2 and NO adsorption on AC, other adsorbents or components, such as zeolite or CO2, have rarely been involved. Meanwhile, it is necessary to investigate the adsorption species on different adsorbents, to supply more information to reveal the dynamic adsorption processes. Therefore, four adsorbents are adopted in this manuscript, single component and multi-component dynamic adsorption are analysed in detail, temperature-programmed desorption coupled mass spectrometry (TPD-MS) is adopted to identify the adsorption species on different adsorbents.

2. EXPERIMENTAL 2.1. Materials and characterization 5


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13X zeolite (13X), 5A zeolite (5A) and MA were chosen from Jiuzhou Chemicals Co., Ltd. in Shanghai. 13X and 5A zeolites were 1.6-2.5 mm spherical particles, the binder was attapulgite. The Si/Al ratio of 13X and 5A were 1.39 and 1.13, respectively. Mesoporous alumina was 1.0-2.0 mm spherical particles. Coconut shell AC was bought from Jibei activated carbon plant in Hebei province, it was 0.45-0.90 mm irregular particle. Before experiments, 13X and 5A were calcined at 773 K for 24 h to desorb water and other contaminant molecules. AC and MA were dried at 383 K for 24 h. N2 adsorption was performed at 77 K through an automatic surface area and porosity analyser (Autosorb iQ, Quantachrome). The mass of samples was 100 mg, and samples were degassed at 527 K for 8 hours. The adsorption point relative pressure range was 10-7~1(p/p0). The specific surface area (SBET) was calculated from the N2 adsorption isotherms using the Brunauer-Emmett-Teller (BET) equation. Also, the pore volume (VT), micropore volume (Vmin), average pore width (D0) and pore size distributions were calculated with the Quenched Solid Density Functional Theory (QSDFT) and Barrett-Joyner-Halenda (BJH) method. The fractal dimension (D) was adopted to describe the roughness of the adsorbent surface and was calculated using the Frenkel-Halsey-Hill (FHH) method.20 2.2. SO2, NO and CO2 adsorption tests The adsorption amounts of SO2, NO and CO2 on absorbents were investigated in a fixed-bed reactor. The quartz tube reactor was 20 mm in diameter and 500 mm in height with a sieve plate in the middle. The gas flow was 500 mL/min. The gaseous hourly space velocity (GHSV) was 9,600 h-1. The simulated flue gas consisted of 500 6


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ppm SO2, 500 ppm NO, 500 ppm CO2, 5 vol.% O2 and a balance of N2 (99.99%). The real flue gas temperature was around 343 K, by preliminary experimental exploration, CO2 adsorption amount decreased greatly with the increase of adsorption temperature, the error of CO2 adsorption amount reached 50% at 343 K. In order to well investigate CO2 dynamic adsorption, the single gas adsorption temperature was set as 293 K, and the multi-component gas adsorption temperature was set as 343 K. After being mixed in the mixing vessel, the gas was fed into the reactor, and the effluent gas was continuously detected using a quadruple mass spectrometer (GAM200, IPI). SO2, NO and CO2 were identified using the major mass ions of 64, 30 and 44, respectively. NO2 was identified using major mass ions of 30 and 46. The SO2 and NO adsorption amounts were calculated from the area integrals of the breakthrough curves, as shown in the following equation (1):

ν=

t F0M (C0 − Ct )dt ∫ 22.4 × m0 0

(1)

Where ν is the adsorbent adsorption amount (mg/g), M is the mole fraction of the adsorbate, F0 is the volumetric feed flow rate (mL/min), m0 is the adsorbent mass (g), 22.4 is the molar volume of the adsorbate (L/mol), C0 is the adsorbate feed concentration (ppm), Ct is the adsorbate concentration (ppm) at time t, and dt is a minimal amount of time variation. 2.3. Adsorption species desorption tests TPD-MS was applied to investigate the adsorption species and absorbents. For gas desorption, the experiments were measured in the temperature range of 300-900 K

7


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with a heating rate of 5 K/min. and N2 was used as the carrier gas. The effluent gas SO2, NO, NO2 and CO2 were continuously monitored using mass spectroscopy.

3. RESULTS AND DISCUSSION 3.1 Adsorbent characterization and single gas adsorption The texture properties of adsorbents are shown in Table 1. AC has the largest specific surface area, pore volume and microspore volume among the four adsorbents. The SBET, VT and Vmin of 13X are 599.0 m3/g, 0.327 ml/g and 0.239 ml/g, they are larger than that of 5A; the D0 of 5A at 0.863 nm is larger than that of 13X. MA belongs to the mesoporous adsorbent, possessing the lowest specific surface area (265.5 m2/g), while its fractal dimension is the highest at 3.439, indicating its irregular surface properties. The pore distributions of these adsorbents are shown in Fig. 1. AC owns the smallest pores, which are mainly distributed at 0.78 and 1.18 nm. The pore distribution of 13X is 1.18 nm; for 5A, they are 0.86 and 1.38 nm; and for MA, they are at 4.09 and 8.46 nm. Fig. S1 of the Supporting Information shows the breakthrough curves of single gas adsorption on adsorbents. The dynamic adsorption curves at time t is obtained by area integrating of the breakthrough curve. The amount of adsorbate adsorbed by the adsorbent calculated as equation (1). The dynamic adsorption curves of SO2, NO and CO2 on the four adsorbents are demonstrated in Fig. 2, and the empirical models of Bangham and Langmuir are used to correlate to the experimental results, while the modelling equations are shown in equation (2) and equation (3).21,22 Bangham

ν =kt1/ m 8


(2)

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Langmuir

ν=νe (1-e-ψt )

(3)

Where ν is the adsorption amount and t is the adsorption time. For the Bangham model, k is the adsorption rate constant and m is the constant. For the Langmuir model, νe indicates the saturated adsorption amount and ψ indicates the synergy of the adsorption and desorption rate constant. A higher value of νe with a smaller value of ψ indicates a longer saturation time. Table S1 of the supporting information shows the Bangham and Langmuir parameters for SO2, NO and CO2 adsorption. Langmuir model is more suitable for describing SO2, NO and CO2 adsorption with the majority of R2 values above 0.98 compared to the Bangham model. This indicates that SO2, NO and CO2 are tending to monolayer adsorbed on the adsorbents, and there might be specific adsorption sites on adsorbents for different gas adsorbates. The number of adsorption sites determines the adsorption amount, the adsorption sites determine the selectivity of adsorption for different adsorbents. 13X possesses the highest SO2 adsorption amounts (228.0 mg/g) among the four adsorbents, which is nearly 6 times higher than AC. For NO adsorption, 5A has the highest adsorption amount of 62.6 mg/g, which is nearly 17 times higher than AC. For CO2 adsorption, 13X has the highest CO2 adsorption amounts of 8.7 mg/g, which is nearly 10 times higher than AC. Although AC has the largest BET surface and micropore volume, the adsorption amounts of all the three gases on AC are lower than zeolite, indicating the essential factor for SO2, NO and CO2 adsorption is not the adsorbent pore structure, other properties such as the adsorbent polarity or chemical 9


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sites might be more favourable for SO2, NO and CO2 adsorption.23 3.2 SO2, NO and CO2 adsorption species analysis Fig. 3 shows SO2 desorption curves for four different adsorbents. There is only one SO2 desorption peak for MA, 13X and 5A, showing single SO2 adsorption species on these adsorbents. The main SO2 desorption temperature for both 13X and 5A is 376 K, which is only 8 K lower than that for MA, indicating SO2 is mainly physically adsorbed. Different from other adsorbents, AC shows two SO2 desorption peaks at 524 K and 610 K. According to previous research,24 the desorption peaks for SO2 at 524 K and 610 K on AC can be attributed to the strong adsorbed SO2 and the chemically adsorbed species (SO3 or sulfate), demonstrating that attachment between SO2 and AC is more strong than that for zeolite or MA. NOx adsorption species are analysed using mass ions 30 (Fig. 4a) and 46 (Fig. 4b); mass ion 30 is the combination of NO and NO2 and mass ion 46 represents NO2. NO adsorption species only show one desorption peak at both mass ions 30 and 46 for AC. The main desorption temperature of mass ion 30 is 388 K and that for mass ion 46 is approximately 400 K, most NO is physically adsorbed on AC and only a small part of NO is oxidized to NO2 on the AC surface.25 The NO desorption curve of MA is inconspicuous. Only the desorption peak at 491 K of mass ion 30 indicates that NO is physically adsorbed, and the higher desorption temperature indicates the stronger attachment with MA than AC. NO desorption behaviour is quite complicated for zeolite. The desorption curves show both physically adsorbed NO at approximately 385 K of mass ion 30, and 10


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constantly desorption behaviours at 600-900 K for mass ions 30 and 46, indicating that substantial NO is chemically adsorbed on zeolite, and the combined forces between NO and zeolite are much tighter than that between NO and other adsorbents. NO tends to be more easily oxidized on zeolite.26 CO2 desorption curves are shown in Fig. 5. Zeolite has the lowest desorption temperatures of 355 K and 378 K, which is followed by MA at 390 K; the highest is for AC at 485 K, indicating the attachment of CO2 with adsorbents follows the order of AC > MA > zeolite, while the adsorption amount of CO2 is in opposition to this order, suggesting the adsorbents properties may be affected by both the adsorption amount and adsorption species. In summary, SO2 can be more easily oxidized on AC than that on zeolite or MA, and NO could almost only be oxidized on zeolite. CO2 is mainly physically adsorbed on these adsorbents due to its no dipole moment and less polarizability.27 The attachment between the adsorbent gas and the adsorbent could be judged by the gas desorption temperature. The lower the desorption temperature, the weaker the combination between adsorbent gas and the adsorbent, that is to say that the gas is more likely to adsorb on the adsorbent.28 For 13X, the main desorption temperature for physically adsorbed SO2, NO and CO2 are 376 K, 363 K and 355 K, respectively, indicating that CO2 is more easily adsorbed on 13X than both SO2 and NO. For 5A, the main desorption temperature for physically adsorbed SO2, NO and CO2 are 376 K, 385 K and 378 K, respectively, indicating that SO2 is more easily adsorbed on 5A than both NO and CO2. For AC, the main desorption temperature for SO2, NO and 11


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CO2 are 524 K, 388 K and 485 K, respectively, indicating that NO is more easily adsorbed on AC than both SO2 and CO2. For MA, the main desorption temperature for SO2, NO and CO2 are 384 K, 491 K and 390 K, respectively, indicating that SO2 is more easily adsorbed on AC than both NO and CO2. 3.3 Multi-component adsorption on zeolite and activated carbon According to the experimental results shown in sections 3.1 and 3.2, AC and zeolite display extremely different behaviours. So in this part, single component, binary components and triple components adsorption are compared between 13X and AC to investigate the adsorbents effects on multi-component adsorption. Fig. S2 and S3 of the Supporting Information show the breakthrough curves of multi-component gas adsorption on 13X and AC, and the dynamic adsorption curves of multi-component gas adsorption on 13X and AC are obtained by area integrating of the breakthrough curve (Fig. S4 and S5 of the Supporting Information). Table S2 of the Supporting Information show the adsorption amounts of multi-component gas adsorption on 13X and AC. Fig. 6 and Fig. 7 show the TPD-MS profiles of SO2 and NO desorption on 13X and AC at four different atmospheres. The changes of the desorption curves show that the adsorption atmospheres affect both the adsorption amounts and the adsorption species. Some desorption curves are superimposed on the desorption peaks of various adsorption species in Fig.6 and Fig.7. These desorption peaks may have different types of adsorption species, therefore, in order to further investigate the distribution of adsorption species, Peakfit v4.12 is used to separate the desorption curves, the fitting method is Gaussian-Lorentz method. The adsorption species distribution and the desorption amount of each product are obtained by peak fitting. The comparison of gas adsorption and desorption amounts show that the gas desorption amounts are approximately equal to the adsorption amounts, therefore, the gas desorption amounts is used for the analysis of adsorbed species. The peak fitting method is shown in Fig. 8, all the peak fitting correlation coefficients (R2) are above 12


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0.98, SO2 and NO adsorption species have been identified according to the previous literature. 11,24,29-32 For SO2 adsorption on 13X (Fig. 9-13X), SO2 adsorption amount decrease after both NO and CO2 being added (S+N, S+C). The inhibitive effect of NO on SO2 is 26.3% higher than that of CO2 on SO2, while this inhibitive effect decrease 5.3% after NO and CO2 put in together, indicating that CO2 reduce the inhibitive effect of NO on SO2 adsorption. The physically adsorbed NO increase by 2.9 times after SO2 put in (N+S), and the CO2 addition promotes physically adsorbed NO by 4.8 times (N+C), indicating the promotive effect of CO2 on physically adsorbed NO is almost twice higher than that of SO2 on physically adsorbed NO. The chemically adsorbed NO disappears after SO2 or SO2 and CO2 put in together (N+S, N+S+C), while CO2 addition only decrease 68.3% chemically adsorbed NO(N+C), showing NO oxidation on 13X is greatly inhibited by SO2, the increase of CO2 on physically adsorbed NO decrease 26.6%. The change of SO2 and NO adsorption amounts and adsorption species show that the interaction effect between SO2 and NO on gas adsorption is the most significant among the three gases on 13X. For SO2 adsorption on AC (Fig. 9-AC), SO2 adsorption amount is obviously promoted by NO, the three SO2 adsorption species are all increased, physically adsorbed SO2 increase 52.9%, strong adsorbed SO2 and SO3 increase by 16.8 times, sulfuric acid and sulfate increase by 2.9 times (S+N), showing the promotive effect of NO on SO2 is mainly for the chemically adsorbed SO2. CO2 addition shows inhibitive for physically adsorbed SO2 with 43.1%, sulfuric acid and sulfate are inhibited, and the strong adsorbed SO2 and SO3 increase by 2.2 times after CO2 put in (S+C), these 13


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results show that most of these adsorption species might be transformed to strong adsorbed SO2 and SO3. The overlap effect of NO and CO2 on SO2 promotes all the three adsorption species, although the promotive effect of CO2 on physically adsorbed SO2 and strong adsorbed SO2 and SO3 are decreased 14.1% and 58.4% comparing with only NO addition (S+N), the promotive effect on sulfuric acid and sulfate is by 1.4 times, indicating that even the CO2 addition decrease the promotive effect of NO on SO2 adsorption, the promotive effect of NO on SO2 oxidation is enhanced due to CO2 addition which might be explained by the promotive effect of CO2 on NO as shown in Fig. 10-AC (N+C). On contrary, NO adsorption is greatly inhibited after SO2 was added as shown in Fig. 10 (N+S), both the physically adsorbed NO or C-O-NO and chemically adsorbed NO are decreased, the physically adsorbed NO or C-O-NO is decreased 61.5%, while the chemically adsorbed NO has almost been disappeared on AC; CO2 promotes physically adsorbed NO or C-O-NO for 7.7%, chemically adsorbed NO for 18.2% (N+C), and the both existence of SO2 and CO2 still shows inhibitive effect on NO adsorption, although CO2 addition decrease the inhibitive effect of SO2 on NO for 8.4% (N+S+C), indicating the inhibitive effect of SO2 mainly dominate NO adsorption on AC. There is only physically adsorbed CO2 on 13X and AC. For CO2 adsorption on 13X (Fig. 11-13X), CO2 adsorption amounts both decreases after SO2 and NO added. The inhibitive effect of NO on CO2 is 25.0% higher than that of CO2 on SO2, and this inhibitive effect increase 8.3% after SO2 and NO put in together. For CO2 adsorption 14


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on AC (Fig. 11-AC), the inhibitive effect of NO on CO2 is also higher than that of CO2 on SO2, the CO2 adsorption amount decrease 55.5% after NO added. Comparison of CO2 adsorption amount with SO2 and NO adsorption shows that there is competitive adsorption between SO2 and CO2, while it is indicated in the study above that CO2 promotes the NO adsorption on 13X and AC, therefore it could be deduced that CO2 promotes the formation of specific NO adsorption species. In summary, CO2 inhibits the SO2 adsorption on 13X and AC, and promotes the NO adsorption on 13X and AC, among the three adsorbates, the interaction between SO2 and NO possesses the greatest effect on the adsorption amounts and adsorption species. CO2 adsorption on 13X and AC both inhibited by SO2 and NO. All in all, multi-component adsorption showing totally different performance between 13X and AC, which is closely related to the adsorption mechanism of different gases. The specific adsorption species has rarely been revealed in other literatures, the effects of adsorbent performance on multi-component gas adsorption could be reflected by these findings.

4. CONCLUSIONS Zeolite has the highest SO2, NO and CO2 adsorption amounts among the four adsorbents, indicating its potential application for multi-component removal. Langmuir is more appropriate to describe SO2, NO and CO2 adsorption processes, indicating SO2, NO and CO2 are mainly monolayer adsorbed and have specific adsorption sites on these adsorbents. The texture properties of adsorbents are not the decisive factors for gas adsorption, adsorbent polarity or chemical sites might be more 15


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favourable to SO2, NO and CO2 adsorption. Gas adsorption species have been investigated, the results illustrate that physically adsorbed SO2 is the main adsorption type on 13X, 5A and MA, and SO2 is more easily oxidized on AC; NO could almost only be oxidized on zeolite, CO2 is mainly physically adsorbed on these adsorbents. According to the desorption temperature of the physically adsorbed species, CO2 is more easily adsorbed on 13X, SO2 is more easily adsorbed on 5A and MA and NO is more easily adsorbed on AC. For multi-component adsorption on different adsorbents, zeolite and AC are compared in the manuscript. For gas adsorption on13X, the inhibitive effect of NO on SO2 is 26.3% higher than that of CO2 on SO2, indicating that NO has a major inhibitory effect on SO2 adsorption. In the presence of SO2, physically adsorbed NO is the only NO adsorption species on 13X, showing NO oxidation on 13X is greatly inhibited by SO2. For gas adsorption on AC, according to a large increase in chemically adsorbed SO2 after NO put in, the promotive effect of NO on SO2 is mainly for the chemically adsorbed SO2. On the contrary, chemically adsorbed NO is almost disappeared and physically adsorbed NO or C-O-NO is just inhibited by 61.5% after SO2 put in, indicating SO2 mainly dominate chemically adsorbed NO on AC. By comparing the effect of CO2 on the gas adsorption on adsorbents, CO2 inhibits the SO2 adsorption on 13X and AC, and promotes the NO adsorption on 13X and AC, that the interaction effect between SO2 and NO on gas adsorption is the most significant among the three gases on 13X. Physically adsorbed CO2 on 13X and AC are both inhibited by SO2 and NO. To 16


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sum up, multi-component adsorption is closely related to the adsorption mechanism of different gases. The effects of adsorbent performance on multi-component gas adsorption could be reflected by these findings.

ACKNOWLEDGMENTS This research was financially supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB10040201) and the National Nature Science Foundation of China (No. 51608508).

References (1) Statistical yearbook of china，National bureau of statistics of the people's republic of china. 2015. (2) You, C.; Xu, X. Energy 2010, 35, 4467-4472. (3) Zhu, J.; Wang, Y.; Zhang, J.; Ma, R. Energ. Convers. Mange. 2005, 46, 2173-2184. (4) Chang, Y.-C.; Wang, N. Energ. Policy. 2010, 38, 3356-3364. (5) Rezaei, F.; Rownaghi, A. A.; Monjezi, S.; Lively, R. P.; Jones, C. W. Energy Fuels 2015, 29, 5467-5486. (6) Czyżewski, A.; Kapica, J.; Moszyński, D.; Pietrzak, R.; Przepiórski, J. Chem. Eng. J. 2013, 226, 348-356. (7) Sayari, A.; Belmabkhout, Y.; Serna-Guerrero, R. Chem. Eng. J. 2011, 171, 760-774. (8) Samanta, A.; Zhao, A.; Shimizu, G. K.; Sarkar, P.; Gupta, R. Ind. Eng. Chem. Res. 2011, 51, 1438-1463. (9) Wickramaratne, N. P.; Jaroniec, M. Acs. Appl. Mater. Inter. 2013, 5, 1849-1855. (10) Zhang, P.; Wanko, H.; Ulrich, J. Chem. Eng. Technol. 2007, 30, 635-641. 17


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19


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Page 20 of 32

Table Table 1. Texture characterization of the adsorbents Sample

AC

13X

5A

MA

SBET (m2/g)

799.9

599.0

507.6

265.5

VT (ml/g）

0.335

0.327

0.281

0.331

Vmic (ml/g)

0.304

0.239

0.193

0.000

D0 (nm)

0.501

0.677

0.863

3.775

D

3.249

2.879

2.948

3.439

20


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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Energy & Fuels

Figure captions Figure 1.Size distribution of the adsorbents Figure 2.Dynamic adsorption curves and the correlations results Figure 3. TPD-MS profiles of SO2 desorption Figure 4. TPD-MS profiles of NOx desorption (a) mass ion 30 (b) mass ion 46 Figure 5. TPD-MS profiles of CO2 desorption Figure 6. TPD-MS profiles of SO2 desorption (S-SO2, N-NO, C-CO2) Figure 7. TPD-MS profiles of NO desorption (S-SO2, N-NO, C-CO2) Figure 8. Peak fitting process of S+N+C on AC Figure 9. SO2 adsorption species distribution Figure 10. NO adsorption species distribution Figure 11. CO2 adsorption species distribution

21


Energy & Fuels

Figure 1

AC 13X 5A MA

1.2 4.09 nm

0.045

0.3

1.18 nm 0.78 nm

dV(d) (ml/nm/g)

dV(d) (ml/nm/g)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 22 of 32

8.46 nm

0.030 0.015 0.000

1.38 nm

0

10

20

30

Pore width (nm)

0.86 nm 0.0 0.0

1.5

3.0 Pore width (nm)

22


4.5

Page 23 of 32

Figure 2

80

300

AC 13X 5A MA Bangham Langmuir

60

120

NO

40

20 60

0

0 4

8

12

0

16

3

6 t (h)

t (h) AC 13X 5A MA Bangham Langmuir

12

8

CO2

2

0

νCO (mg/g)

2

180

AC 13X 5A MA Bangham Langmuir

SO2

νNO (mg/g)

240

νSO (mg/g)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Energy & Fuels

4

0 0.0

0.3

0.6

0.9

1.2

1.5

t (h)

23


1.8

9

12

Energy & Fuels

Figure 3

80

-12

Ion current [×10 A]

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 24 of 32

376K

AC 13X 5A MA

60

40

20 524K

384K

0 300

450

610K 600 T (K)

24


750

900

Page 25 of 32

Figure 4

25

-12

385K 388K 363K

676K

736K

20 491K

0 300

450

AC 13X 5A MA

20 841K

40

(b)

-13

60

m/e=30


AC 13X 5A MA

(a)


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Energy & Fuels

15

10

674K 724K

m/e=46

819K

400K 437K

5 600

750

900

300

450

600 T (K)

T (K)

25


750

900

Energy & Fuels

Figure 5

24 AC 13X 5A MA

378K 18 355K

-12


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 26 of 32

12

390K

485K 6

300

450

600 T (K)

26


750

Page 27 of 32

Figure 6

13X

100 S S+N S+C S+N+C

435K

-12

70

0 300

450

600

S S+N S+C S+N+C

554K

75

425K 416K 409K

140

AC

-12

210

Ion Current [×10 A]

280


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Energy & Fuels

750

900

50 390K

627K

25 599K

0 300

450

600 T (K)

T (K)

27


750

900

Energy & Fuels

Figure 7

m/e=30 400/430/448/500/539K N N+S N+C 867K N+S+C

90 60 -12

30 0 3.3

500K

2.2 550K

N N+S N+C N+S+C 782K

m/e=46

35

m/e=30

AC 443K

28 -12

13X


120


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 28 of 32

570K 527K

378K

21 14

N N+S N+C N+S+C

398K

7

1.1 0.0 300

450

600 T (K)

750

0 300

900

450

600 T (K)

28


750

900

Page 29 of 32

Figure 8

24

2

R =0.9973 380.7 K 18 -12


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Energy & Fuels

12 598.8 K 6

0 300

680.2 K

450

600 T (K)

29


750

900

Energy & Fuels

Figure 9

180 13X

Physically adsorbed SO2

AC

Physically adsorbed SO2 Adsorption amount (mg/g)

Adsorption amount (mg/g)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 30 of 32

120

60

120

Strong adsorbed SO2 and SO3 Sulfuric acid and sulfate

80

40

0

0 S

S+N S+C Atomsphere tags

S

S+N+C

30


S+N S+C Atomsphere tags

S+N+C

Page 31 of 32

Figure 10

4

18 13X

Physically adsorbed NO Chemically adsorbed NO



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Energy & Fuels

12

6

0

AC

Physically adsorbed NO or C-O-NO Chemically adsorbed NO

3

2

1

0 N

N+S N+C Atomsphere tags

N+S+C

N

31


N+S N+C Atomsphere tags

N+S+C

Energy & Fuels

Figure 11 1.5

13X

Physically adsorbed CO2


2 Adsorption amount (mg/g)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 32 of 32

1

AC

Physically adsorbed CO2

1.0

0.5

0.0

0 C

C+S C+N Atmosphere tags

C

C+S+N

32


C+S C+N Atmosphere tags

C+S+N

Adsorption Species Distribution and Multicomponent Adsorption

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