Abstract
Purpose
Biochar has unique properties which make it a powerful tool to increase soil fertility and to contribute to the decrease of the amount of atmospheric carbon dioxide through the mechanisms of C sequestration in soils. Chemical and physical biochar characteristics depend upon the technique used for its production and the biomass nature. For this reason, biochar characterization is very important in order to address its use either for agricultural or environmental purposes.
Materials and methods
Three different biochars obtained from an industrial gasification process were selected in order to establish their chemical and physical peculiarities for a possible use in agronomical practices. They were obtained by charring residues from the wine-making industry (marc) and from poplar and conifer forests. Routine analyses such as pH measurements, elemental composition, and ash and metal contents were performed together with the evaluation of the cross-polarization magic angle spinning (CPMAS) 13C NMR spectra of all the biochar samples. Finally, relaxometry properties of water-saturated biochars were retrieved in order to obtain information on pore size distribution.
Results and discussion
All the biochars revealed basic pH values due to their large content of alkaline metals. The quality of CPMAS 13C NMR spectra, which showed the typical signal pattern for charred systems, was not affected by the presence of paramagnetic centers. Although paramagnetism was negligible for the acquisition of solid state spectra, it was effective in some of the relaxometry experiments. For this reason, no useful information could be retrieved about water dynamics in marc char. Conversely, both relaxograms and nuclear magnetic resonance dispersion profiles of poplar and conifer chars indicated that poplar char is richer in small-sized pores, while larger pores appear to be characteristic for the conifer char.
Conclusions
This study showed the potential of relaxometry in revealing chemical–physical information on industrially produced biochar. This knowledge is of paramount importance to properly direct biochar agronomical uses.
Similar content being viewed by others
References
Albano AM, Beckmann PA, Carrington ME, Fusco FA, O’Neil AE, Scott ME (1983) A general NMR spectral density and its experimental verification. J Phys C Solid State Phys 16:L979–L983
Anoardo E, Galli G, Ferrante G (2001) Fast-field-cycling NMR: applications and instrumentation. Appl Magn Reson 20:365–404
Bakhmutov VI (2004) Practical NMR relaxation for chemists. Wiley, Chichester
Basu P (2010) Biomass gasification and pyrolysis: practical design and theory. Academic Press, New York, ISBN: 9780123749888
Berns AE, Conte P (2010) Effect of RF field inhomogeneity and sample restriction on spectral resolution of CP/MAS-13C NMR spectra of natural organic matter. Open Magn Reson J 3:75–83
Berns AE, Conte P (2011) Effect of ramp size and sample spinning speed on CPMAS 13C NMR spectra of soil organic matter. Org Geochem 42(8):926–935
Borgia GC, Brown RJS, Fantazzini P (1998) Uniform-penalty inversion of multiexponential decay data. J Magn Reson 132:65–77
Borgia GC, Brown RJS, Fantazzini P (2000) Uniform-penalty inversion of multiexponential decay data: II. Data spacing, T2 data, systematic data errors, and diagnostics. J Magn Reson 147:273–285
Brewer CE, Unger R, Schidt-Rohr K, Brown RC (2011) Criteria to select biochars for field studies based on biochar chemical properties. Bioenerg Resour 4(4):312–323
Cheng HN, Wartelle LH, Klasson KT, Edwards JC (2010) Solid-state NMR and ESR studies of activated carbons produced from pecan shells. Carbon 48:2455–2469
Conte P, Piccolo A, van Lagen B, Buurman P, Hemminga MA (2001) Effect of residual ashes on CPMAS-13C NMR spectra of humic substances from volcanic soils. Fresenius Environ Bull 10:368–374
Conte P, Spaccini R, Piccolo A (2004) State of the art of CPMAS 13C-NMR spectroscopy applied to natural organic matter. Prog Nucl Magn Reson Spectrosc 44:215–223
Downie A, Crosky A, Munroe P (2009) Physical properties of biochar. In: Lehmann J, Joseph S (eds) Biochar for environmental management: science and technology. Earthscan, London, pp 13–33
Dumbleton F (1997) Biomass conversion technologies: an overwiew. Asp Appl Biol 49:341–347
Dunn KJ, Bergman DJ, Latorraca GA (2002) Handbook of geographic exploration-seismic exploration: nuclear magnetic resonance petrophysical and logging applications. Elsevier, Oxford
Feng J-W, Zheng S, Maciel GE (2004) EPR investigations of the effects of inorganic additivities on the charring and char/air interactions of cellulose. Energy Fuel 18:1049–1065
Ferrante G, Sykora S (2005) Technical aspects of fast field cycling. Adv Inorg Chem 57:405–470
Gundale MJ, De Luca TH (2006) Temperature and source material influence ecological attributes of ponderosa pine and Douglas-fir charcoal. For Ecol Manag 231:86–93
Halle B, Johannesson H, Venu K (1998) Model-free analysis of stretched relaxation dispersions. J Magn Reson 135:1–13
Kimmich R, Anoardo E (2004) Field-cycling NMR relaxometry. Prog Nucl Magn Reson Spectrosc 44:257–320
Knicker H (2011) Pyrogenic organic matter in soil: its origin and occurrence, its chemistry and survival in soil environments. Quat Int 243(2):251–263
Korb JP (2011) Nuclear magnetic relaxation of liquids in porous media. New J Phys 13:035016
Krull ES, Baldock JA, Smernik RJ, Skjemstad O (2009) Characteristics of biochar: organo-chemical properties. In: Lehmann J, Joseph S (eds) Biochar for environmental management: science and technology. Earthscan, London, pp 53–63
Lehmann J, Joseph S (2009) Biochar for environmental management: an introduction. In: Lehmann J, Joseph S (eds) Biochar for environmental management: science and technology. Earthscan, London, pp 1–13
Luchinat C, Parigi G (2008) Nuclear relaxometry helps designing systems for solution DNP on proteins. Appl Magn Reson 34:379–392
Luo X, Sholl CA (2002) Theory of nuclear spin relaxation in disordered systems: comparison of Bloembergen-Purcell-Pound models and Monte Carlo simulations. J Phys Condens Matter 14:6941–6948
McBeath AV, Smernik RJ (2009) Variation in the degree of aromatic condensation of chars. Org Geochem 40:1161–1168
McDonald PJ, Korb J-P, Mitchell J, Monteilhet L (2005) Surface relaxation and chemical exchange in hydrating cement pastes: a two-dimensional NMR relaxation study. Phys Rev E 72:011409
Morozova-Roche LA, Jones JA, Noppe W, Dobson CM (1999) Independent nucleation and heterogeneous assembly of structure during folding of equine lysozyme. J Mol Biol 289:1055–1073
Mullen CA, Boateng AA, Goldberg NM, Lima IM, Laird DA, Hicks KB (2010) Bio-oil and bio-char production from corn cobs and stover by fast pyrolysis. Biomass Bioenergy 34:67–74
Pohlmeier A, Haber-Pohlmeier S, Stapf S (2009) A fast field cycling nuclear magnetic resonance relaxometry study of natural soils. Vadose Zone J 8:735–742
Preston CM (1996) Applications of NMR to soil organic matter analysis: history and prospects. Soil Sci 161:144–166
Sacier KM (1983) Effects of catalysts and steam gasification on E.S.R. of carbon black. Fuel 62:331–335
Sacier KM (1984) Effects of catalysts and CO2 gasification on the E.S.R. of carbon black. Fuel 63:679–685
Schure MR, Soltys PA, Natusch DFS, Mauney T (1985) Surface area and porosity of coal fly ash. Environ Sci Technol 19:82–86
Smernik RJ, Oades JM (2000a) The use of spin counting for determining quantitation in solid state [sup. 13]C NMR spectra of natural organic matter. 1. Model systems and the effects of paramagnetic impurities. Geoderma 96:101–129
Smernik RJ, Oades JM (2000b) The use of spin counting for determining quantitation in solid state [sup. 13]C NMR spectra of natural organic matter. 2. HF-treated soil fractions. Geoderma 96:159–171
Tranchina L, Basile S, Brai M, Caruso A, Cosentino C, Miccichè S (2008) Distribution of heavy metals in marine sediments of Palermo Gulf (Sicily, Italy). Water Air Soil Pollut 191:245–256
Warnock DD, Lehmann J, Kuyper TW, Rilling MC (2007) Mycorrhizal responses to biochar in soil—concepts and mechanisms. Plant Soil 300:9–20
White RE (2005) Principles and practice of soil science: the soil as a natural resource, 4th edn. Blackwell, Malden
Acknowledgments
P.C. acknowledges Forschungszentrum Jülich GmbH (Germany) for having invited him as visiting scientist at the NMR Center of the Institute of Bio- and Geosciences, IBG-3: Agrosphere. FFC NMR measurements were done at the Università degli Studi di Palermo. The authors are very grateful to Dr. Salvatore Bubici (INVENTO S.r.l.) for the fruitful discussion about FFC NMR relaxometry and to Professor Heike Knicker (Consejo Superior de Investigaciones Cientifĉas, Spain) for the useful comments on the CPMAS 13C NMR spectra.
Author information
Authors and Affiliations
Corresponding author
Additional information
Responsible editor: Chris Johnson
Rights and permissions
About this article
Cite this article
De Pasquale, C., Marsala, V., Berns, A.E. et al. Fast field cycling NMR relaxometry characterization of biochars obtained from an industrial thermochemical process. J Soils Sediments 12, 1211–1221 (2012). https://doi.org/10.1007/s11368-012-0489-x
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11368-012-0489-x