Skip to main content
SpringerLink
Log in

The effect of small micropores on methane adsorption of coals from Northern China

  • Published:
Adsorption Aims and scope Submit manuscript

Abstract

In this study, the effect of coal micropores on the adsorption properties, especially the Langmuir pressure (P L ), was investigated by testing 11 coal samples from Northern China. The adsorption of CO2 at 273 K was utilized to analyze the pore size distribution. The results of these coals show that micropore volume and micropore surface area are the major factors affecting the Langmuir volume (V L ) but have weaker effects on P L . Micropore filling theory considers that some smaller micropores with an obvious overlapping adsorption force cause volume filling adsorption. These micropores firstly reach saturated adsorption, controlling the adsorption volume at the low-pressure stage and thus have a great effect on P L . Four times the methane molecular diameter, 1.5 nm, was assumed as the critical pore size with obvious overlapping adsorption force. The relationship between P L and the proportion of the pore volume below 1.5 nm to the micropore volume was investigated, and it was found that the higher the volume proportion of these small micropores was, the smaller the P L was, though two data points deviated from this trend. The reason for the anomalous coal samples could be the deviation from the assumed critical pore size of 1.5 nm for volume filling and the effects of the various micropore surface properties, which await further study.

The micropore surface increases with increasing coal rank, as does V L . The proportion of pore volume below 1.5 nm increases with coal rank, and P L reverses. However, these relationships are discrete.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9

Similar content being viewed by others

Abbreviations

V L ::

Langmuir volume [mL/g]

P L ::

Langmuir pressure [MPa]

P::

Pressure [MPa]

V::

Volume [mL]

ad::

air dried basis

daf::

dry ash-free basis

R o,max::

Mean maximum reflectance of vitrinite [%]

References

  • Boyer, C.M. II, Bai, Q.Z.: Methodology of coalbed methane resource assessment. Int. J. Coal Geol. 35, 349–368 (1998)

    Article  CAS  Google Scholar 

  • Bustin, R.M., Clarkson, C.R.: Geological controls on coalbed methane reservoir capacity and gas content. Int. J. Coal Geol. 38, 3–26 (1998)

    Article  CAS  Google Scholar 

  • Cao, D., Wang, W., Shen, Z., Chen, J.: Determination of pore size distribution and adsorption of methane and CCl4 on activated carbon by molecular simulation. Carbon 40, 2359–2365 (2002)

    Article  CAS  Google Scholar 

  • Carrott, P.J.M., Roberts, R.A., Sing, K.S.W.: Adsorption of nitrogen by porous and non-porous carbons. Carbon 25, 59–68 (1987)

    Article  CAS  Google Scholar 

  • China Department of Coal Industry: MT/T752-1997 Determining method of methane adsorption capacity in coal. Beijing, China (1997)

  • China State Administration of Work Safety: MT/T 1087-2008 Test methods for proximate analysis of coal by instruments. Beijing, China (2009)

  • Clarkson, C.R., Bustin, R.M.: Variation in micropore capacity and size distribution with composition in bituminous coal of the Western Canadian Sedimentary Basin: implications for coalbed methane potential. Fuel 75, 1483–1498 (1996)

    Article  CAS  Google Scholar 

  • Clarkson, C.R., Bustin, R.M.: The effect of pore structure and gas pressure upon the transport properties of coal: a laboratory and modeling study. 1. Isotherms and pore volume distributions. Fuel 78, 1333–1344 (1999)

    Article  CAS  Google Scholar 

  • Clarkson, C.R., Bustin, R.M., Levy, J.H.: Application of the mono/multilayer and adsorption potential theories to coal methane adsorption isotherms at elevated temperature and pressure. Carbon 35, 1689–1705 (1997)

    Article  CAS  Google Scholar 

  • Cracknell, R.F., Gordon, P., Gubbins, K.E.: Influence of pore geometry on the design of microporous materials for methane storage. J. Phys. Chem. 97, 494–499 (1993)

    Article  CAS  Google Scholar 

  • Crosdale, P.J., Beamish, B.B., Valix, M.: Coalbed methane sorption related to coal composition. Int. J. Coal Geol. 35, 147–158 (1998)

    Article  CAS  Google Scholar 

  • Cui, X., Bustin, R.M., Dipple, G.: Selective transport of CO2, CH4, and N2 in coals: insights from modeling of experimental gas adsorption data. Fuel 83, 293–303 (2004)

    Article  CAS  Google Scholar 

  • Dubinin, M.M.: The potential theory of adsorption of gases and vapors for adsorbents with energetically nonuniform surfaces. Chem. Rev. 60, 235–241 (1960)

    Article  CAS  Google Scholar 

  • Dubinin, M.M., Astakhov, V.A.: Description of adsorption equilibria of vapors on zeolites over wide ranges of temperature and pressure. Adv. Chem. 102, 69–85 (1971)

    Article  CAS  Google Scholar 

  • Dutta, P., Bhowmik, S., Das, S.: Methane and carbon dioxide sorption on a set of coals from India. Int. J. Coal Geol. 85, 289–299 (2011)

    Article  CAS  Google Scholar 

  • Gan, H., Nandi, S.P., Walker, P.L.: Nature of the porosity in American coals. Fuel 51, 272–277 (1972)

    Article  CAS  Google Scholar 

  • General Administration of Quality Supervision, Inspection and Quarantine of the People’s Republic of China and Standardization Administration of the People’s Republic of China: Method of preparing coal samples for the coal petrographic analysis. Beijing, China (2008a)

  • General Administration of Quality Supervision, Inspection and Quarantine of the People’s Republic of China and Standardization administration of the People’s Republic of China: Method of determining microscopically the reflectance of vitrinite in coal. Beijing, China (2008b)

  • Harris, L.A., Yust, C.S.: The ultrafine structure of coal determined by electron microscopy. Am. Chem. Soc. Div. Fuel Chem. 24, 210–217 (1979). Preprints

    Google Scholar 

  • ISO: ISO 111760:2005, Classification of coals. (2005)

  • IUPAC: Reporting physisorption data for gas/solid systems. Pure Appl. Chem. 57, 2201–2218 (1985)

    Google Scholar 

  • IUPAC: Recommendations for the characterization of porous solids. Pure Appl. Chem. 66, 1739–1758 (1994)

    Article  Google Scholar 

  • Jacek, S.: The influence of sorption processes on gas stresses leading to the coal and gas outburst in the laboratory conditions. Fuel 90, 1018–1023 (2011)

    Article  Google Scholar 

  • Kakei, K., Ozeki, S., Suzuki, T., Kaneko, K.: Multi-stage micropore filling mechanism of nitrogen on microporous and micrographitic carbons. J. Chem. Soc. Faraday Trans. 86, 371–376 (1990)

    Article  CAS  Google Scholar 

  • Kaneko, K.: Chapter 2.10 Micropore filling mechanism in inorganic sorbents. Stud. Surf. Sci. Catal. 99, 573–598 (1996)

    Article  CAS  Google Scholar 

  • Langmuir, I.: The adsorption of gases on plane surfaces of glass, mica and platinum. J. Am. Chem. Soc. 40, 1361–1403 (1918)

    Article  CAS  Google Scholar 

  • Lamberson, M.N., Bustin, R.M.: Coalbed methane characteristics of gates formation coals, Northeastern British Columbia: effect of maceral composition. Am. Assoc. Pet. Geol. Bull. 77, 2062–2076 (1993)

    CAS  Google Scholar 

  • Laxminarayana, C., Crosdale, P.J.: Role of coal type and rank on methane sorption characteristics of Bowen Basin, Australia coals. Int. J. Coal Geol. 40, 309–325 (1999)

    Article  CAS  Google Scholar 

  • Levy, J.H., Day, S.J., Killingley, J.S.: Methane capacities of Bowen Basin coals related to coal properties. Fuel 76, 813–819 (1997)

    Article  CAS  Google Scholar 

  • Lozano-Castello, D., Cazorla-Amoros, D., Linares-Solano, A.: Usefulness of CO2 adsorption at 273 K for the characterization of porous carbons. Carbon 42, 1233–1242 (2004)

    Article  CAS  Google Scholar 

  • Marsh, H.: Adsorption methods to study microporosity in coals and carbons—a critique. Carbon 25, 49–58 (1987)

    Article  CAS  Google Scholar 

  • Mastalerz, M., Drobniak, A., Rupp, J.: Meso-and micropore characteristics of coal lithotypes: implications for CO2 adsorption. Energy Fuels 22, 4049–4061 (2008)

    Article  CAS  Google Scholar 

  • Pashin, J.C.: Variable gas saturation in coalbed methane reservoirs of the Black Warrior Basin: implications for exploration and production. Int. J. Coal Geol. 82, 135–146 (2010)

    Article  CAS  Google Scholar 

  • Prinz, D., Littke, R.: Development of the micro- and ultramicroporous structure of coals with rank as deduced from the accessibility to water. Fuel 84, 1645–1652 (2005)

    CAS  Google Scholar 

  • Ruppel, T.C., Grein, C.T., Bienstock, D.: Adsorption of methane on dry coal at elevated pressure. Fuel 53, 152–162 (1974)

    Article  CAS  Google Scholar 

  • Sing, K.S.W., Everett, D.H., Haul, R., Moscou, L., Pierotti, R.A., Rouquerol, J., Siemieniewska, T.: Reporting physisorption data for gas/solid systems with special reference to the determination of surface area and porosity. Pure Appl. Chem. 54, 2201–22l8 (1982)

    Article  Google Scholar 

  • Spitzer, Z.: Mercury porosimetry and its application to the analysis of coal pore structure. Powder Technol. 29, 177–186 (1981)

    Article  CAS  Google Scholar 

  • State Bureau of Quality Technology Supervision of the People’s Republic of China: Determination of maceral group composition and minerals coal China standard press. Beijing, China (1998)

  • Unsworth, J.F., Fowler, C.S., Jones, L.F.: Moisture in coal: 2. Maceral effects on pore structure. Fuel 68, 18–26 (1989)

    Article  CAS  Google Scholar 

  • Valliappan, S., Zhang, W.H.: Role of gas energy during coal outbursts. Int. J. Numer. Methods Eng. 44, 875–895 (1999)

    Article  Google Scholar 

Download references

Acknowledgements

Thanks for the financial support from the National Basic Research Program of China (973 Program, No. 2011CB201204), the National Foundation of China (No. 51074160 and No. 51004106) and the National Postdoctoral foundation of China General Program (No. 2012M510145).

Author information

Authors and Affiliations

  1. National Engineering Research Center for Coal & Gas Control, China University of Mining & Technology, Xuzhou, 221008, China

    Feng-Hua An, Yuan-Ping Cheng, Dong-Mei Wu & Liang Wang

Authors
  1. Feng-Hua An
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Yuan-Ping Cheng
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Dong-Mei Wu
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Liang Wang
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Yuan-Ping Cheng.

Rights and permissions

Reprints and permissions

About this article

Cite this article

An, FH., Cheng, YP., Wu, DM. et al. The effect of small micropores on methane adsorption of coals from Northern China. Adsorption 19, 83–90 (2013). https://doi.org/10.1007/s10450-012-9421-3

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10450-012-9421-3

Keywords

Search

Navigation