Dr. Stephan Kaufhold
Employee of Section B2.1
Geophysical exploration – Technical mineralogy
Tel.: +49-(0)511-643-2765
Fax: +49-(0)511-643-3664
stephan.kaufhold@bgr.de
Visiting address:
Stilleweg 2, room D28
30655 Hannover
Fields of Research and Interest
- Properties of clays and natural functional raw materials
- Applicability of bentonites in European HLRW repositories
- Adsorption mechanisms in soils and geotechnical barriers
- Development of new or modified mineralogical methods frequently based on a collection of reference materials
Methodology
- IR-spectroscopy, chemical and colloidchemical methods (CEC, LCD, PAD), electron microscopy, thermal analysis
Scientific Career
| 1993 - 1998 | Diplom mineralogist, RWTH Aachen |
| 1998 - 2001 | IKO-Erbslöh Industriemineralien und Kohlenstoffe GmbH & Co. KG |
| 2001 | PhD, RWTH Aachen |
| 2001 - 2002 | S&B industrial minerals, R&D department, head of pilot plant |
| 2002 | scientific employee, BGR, technical mineralogy |
Honors
- Karl-Heinrich Heitfeld Award (1999)
- Redenplakette GDMB (2000)
- Friedrich-Wilhelm Award (2002)
- Karl-Jasmund Preis der DTTG (2013)
- Lagaly Award DTTG/MECC (2018)
Publications (Reviewed articles)
Kaufhold, S., Dohrmann, R., Ufer, K., Meyer, F.M., (2002) Comparison of methods for the quantification of montmorillonite in bentonites. – Applied Clay Science 22, S. p. 145 – 151
Kaufhold, S., Penner, D. (2006) Applicability of the SER method for quality control of clays from the German ‘Westerwald´. – Applied Clay Science, 32, 53 – 63.
Kaufhold, S. (2006) Comparison of methods for the determination of the layer charge density (LCD) of montmorillonites. Applied Clay Science, 34, p. 14-21
Kaufhold, S. (2007) Ecuadorian Allophane. Industrial Minerals, May 2007, p. 95.
Kaufhold, S., Pohlmann-Lortz, M., Dohrmann, R., Nüesch, R. (2007) About the possible upgrade of bentonite with respect to iodide retention capacity. - Applied Clay Science, 35, 39–46
2008
Kaufhold, S., Dohrmann, R. (2008) Detachment of colloidal particles from bentonites in water. Applied Clay Science, 39, p. 50–59.
Kaufhold, S., Dohrmann, R. (2008) Comparison of the traditional Enlsin-Neff method and the modified Dieng method for measuring water-uptake capacity. – Clays and clay minerals, 56, 6, p. 686-692.
Kaufhold, S., Dohrmann, R., Ulrichs, Ch. (2008) Shelf life stability of diatomites. – Applied Clay science, 41, p. 158–164.
Kaufhold, S., Dohrmann, R., Koch, D., Houben, G. (2008) The pH of aqueous bentonite suspensions. Clays and Clay Minerals, 56, 338–343.
2009
Kaufhold, S., Kaufhold, A., Jahn, R., Brito, S., Dohrmann, R., Hoffmann, R., Gliemann, H., Weidler, P., Frechen, M. (2009) A new massive deposit of allophane raw material in Ecuador. – Clays and clay minerals, 57, p. 72 – 81.
Kaufhold, S., Dohrmann, R. (2009) Stability of bentonites in salt solutions I sodium chloride. – Applied clay science, 45, 3, p. 171 – 177.
Kaufhold, S., Stührenberg, D., Dohrmann, R. (2009) Water redistribution between bentonite and halite at elevated temperature. – Applied Clay Science, 46, 245 – 250.
2010
Kaufhold, S., Dohrmann, R., Klinkenberg, M. (2010) Water uptake capacity of bentonites. – Clays and Clay Minerals, 58, 37–43.
Kaufhold, S., Dohrmann, R. (2010a) Effect of extensive drying on the cation exchange capacity of bentonites. – Clay Minerals, Vol. 45, No. 4, p. 441 – 448.
Kaufhold, S., Dohrmann, R. (2010b) Stability of bentonites in salt solutions II. Potassium chloride solution — Initial step of illitization? – Applied Clay Science, 49, 98 – 107.
Kaufhold, S., Dohrmann, R., Klinkenberg, M., Siegesmund, S., Ufer, K. (2010) N2-BET specific surface area of bentonites. – Journal of Colloid and Interface Science, Vol. 349, p. 275–282.
Kaufhold, S., Dohrmann, R., Abidin, Z., Henmi, T., Matsue, N., Eichinger, L., Kaufhold, A., Jahn, R. (2010) Fluoride adsorption on allophane. – Applied Clay Science, 50, 25 – 33.
Kaufhold, S., Ufer, K., Kaufhold, A., Stucki, J., Anastácio, A., Jahn, R., Dohrmann, R. (2010) Quantification of allophane clay from Ecuador. – Clays and Clay Minerals, Vol. 58, No. 5, 707–716.
2011
Kaufhold, S., Dohrmann, R. (2011) Stability of bentonites in salt solutions III Ca-hydroxide solutions. – Applied Clay Science 51, 300–307.
Kaufhold, S., Dohrmann, R., Stucki, J., Anastácio, A.S. (2011) Layer charge density of montmorillonite – closing the gap between structural formula method and alkyl ammonium method. – Clays and Clay Minerals, Vol. 59, No. 2, 200–211.
Kaufhold, S., Dohrmann, R., Ufer, K., Kleeberg, R., Stanjek, H. (2011) Cu trien exchange to improve the analytical understanding of smectites. – Clay Minerals, 46, 411 – 420.
Kaufhold, S., Stanjek, H., Penner, D., Dohrmann, R. (2011) The acidity of surface groups of dioctahedral smectites. – Clays and Clay Minerals, 46, 583–592.
2012
Kaufhold, S., Hein, M., Dohrmann, R., Ufer, K. (2012) Quantification of the mineralogical composition of clays using FTIR spectroscopy. – Journal of Vibrational Spectroscopy, 59, 29 - 39.
Kaufhold, S., Dill, H.G., Dohrmann, R. (2012) Clay mineralogy and rock strength of a mid-German diabase - implications for improved quality control. – Clay minerals, 47, 419–428.
Kaufhold, S., Plötze, M., Klinkenberg, M., Dohrmann, R. (2012) Density and porosity of bentonites. – Journal of porous materials, DOI 10.1007/s10934-012-9589-7
2013
Kaufhold, S., Plötze, M., Klinkenberg, M., Dohrmann, R. (2013) Density and porosity of bentonites. – Journal of porous materials, 20:191–208; DOI 10.1007/s10934-012-9589-7.
Kaufhold, S., Dohrmann, R. (2013) The variable charge of dioctahedral clay minerals. – Journal of Colloid and Interface Science, Volume 390, Issue 1, 15 January 2013, Pages 225–233.
Kaufhold, S., Klinkenberg, M., Dohrmann, R. (2013) Comparison of the dry density of highly compacted bentonites. - Clay Minerals, 48, 105–115.
Kaufhold, S., Dohrmann, R., Sandén, T., Sellin, P., Svensson, D. (2013) Mineralogical investigations of the alternative buffer material test – I. Alteration of bentonites. – Clay Minerals, (2013) 48, 199–213.
Kaufhold, S., Emmerich, K., Dohrmann, R., Steudel, A., Ufer, K. (2013) Comparison of methods for distinguishing sodium carbonate activated from natural sodium bentonites. - Applied Clay Science, 86, 23–37.
2014
Kaufhold, S., Grissemann, C., Dohrmann, R., Klinkenberg, M., Decher, A. (2014) Comparison of three small scale devices for the investigation of the electrical conductivity / resistivity of swelling and other clays. – Clays and Clay Minerals, 62, 1–12.
Kaufhold, S., Reese, A., Schwiebacher, W., Dohrmann, R., Grathoff, G.H., Warr, L.N., Halisch, M., Müller, C., Schwarz-Schampera, U., Ufer, K. (2014) Porosity and distribution of water in perlite from the island of Milos, Greece. – SpringerPlus, 3: 598, doi:10.1186/2193-1801-3-598, http://www.springerplus.com/content/3/1/598.
2015
Kaufhold, S., Sanders, D., Dohrmann, R., Hassel, A.-W. (2015) Fe corrosion in contact with bentonites. – Journal of Hazardous Materials, 285, 464–473.
Kaufhold, S., Baille, W., Schanz, T., Dohrmann, R. (2015) About differences of swelling pressure — dry density relations of compacted bentonites. - Applied Clay Science, 107, 52–61.
Kaufhold S., Dohrmann, R., Klinkenberg, M., Noell, U. (2015) Electrical conductivity of swelling clays. - Applied Clay Science, 114, 375–385.
Kaufhold, S., Färber, G., Dohrmann, R., Ufer, K. (2015) A Zn smectite from the Silver Coin Mine, Nevada. – Clay Minerals, (2015) 50, 417–430
2016
Kaufhold, S., Dohrmann, R. (2016) Distinguishing between more and less suitable bentonites for storage of high-level radioactive waste. – Clay Minerals, 51, 289-302.
Kaufhold, S., Houben, G., Dietel, J., Bertmer, M., Dohrmann, R. (2016) Characterization of aluminum phosphate nanoparticles formed in a water well. – Journal of Nanoparticle Research, 18:273, 1-11.
Kaufhold, S., Grathoff, G., Halisch, M., Plötze, M., Kus, J., Ufer, K., Dohrmann, R., Ladage, S., Ostertag-Henning, Ch. (2016) Comparison of methods for the determination of the pore system of a potential German gas shale. - The Clay Minerals Society Workshop Lectures Series, 21, 163–190.
Kaufhold, S., Dohrmann, R., Ufer, K. (2016) Interaction of magnesium cations with dioctahedral smectites under HLRW repository conditions. – Clays and Clay Minerals, 64, 743 – 752.
2017
Kaufhold, S., Stucki, J.W., Finck, N., Steininger, R., Zimina, A., Dohrmann, R., Ufer, K., Pentrák, M., Pentráková, L. (2017) Tetrahedral charge and Fe content in dioctahedral smectites. – Clay minerals, 52, 51 – 55.
Kaufhold, S., Dohrmann, R., Götze, N., Svensson, D. (2017) Characterisation of the second parcel of the alternative buffer material (ABM) experiment – I mineralogical reactions. – Clays and Clay Minerals, 65, 27 – 41.
Kaufhold, S., Dohrmann, R., Gröger-Trampe, J. (2017) Reaction of native copper in contact with pyrite and bentonite in anaerobic water at elevated temperature. – Corrosion Engineering Science and Technology, 52, 349 – 358.
Kaufhold, S., Kremleva, A., Krüger, S., Rösch, N., Emmerich, K., Dohrmann, R. (2017) Crystal-Chemical Composition of Dicoctahedral Smectites: An Energy-Based Assessment of Empirical Relations. - ACS Earth Space Chemistry, 1, 629−636; DOI: 10.1021/acsearthspacechem.7b00082.
2018
Kaufhold, S., Kaufhold, A., Dohrmann, R. (2018) Comparison of the Critical Coagulation Concentrations of Allophane and Smectites. - Colloids Interfaces 2018, 2, 12; doi:10.3390/colloids2010012.
Kaufhold, S., Chryssikos, G.D., Kacandes, G., Gionis, V., Ufer, K., Dohrmann, R. (2018) Geochemical and mineralogical characterisation of smectites from the Ventzia basin, western Macedonia, Greece. – Clay Minerals, in print.
2019
Kaufhold, S., Dohrmann, R., Degtjarev, A., Koeniger, P. (submitted to ACS) Mg and Si solubility of dioctahedral smectites in dispersion. – submitted to ACS, 2018.
Kaufhold, S. ed. (2019) Bentonites – from mine to application. – Geologisches Jahrbuch B 107, Schweizerbart, ISBN 978-3-510-96859-6.
Kaufhold, S., Dohrmann, R., Ufer, K., Kober, F. (2019) Interactions of bentonite with metal and concrete from the FEBEX experiment - mineralogical and geochemical investigations of selected sampling sites. – accepted manuscript Clay Minerals.
Patents
Kaufhold, S., Decher, A., Dohrmann, R. (2000) Verfahren zur Bestimmung des Gehaltes an Tonmineralien in einem tonmineralhaltigen Material. - DE 19839531 A1.
Sohling, U., Ruf, F., Condemarin, R., Kaufhold, S. (2009) Aufreinigung von Biodiesel mittels Allophan und/oder Imogolit. – DE 10 2007 059 620 A1 / Purification of biodiesel by means of allophane and/or imogolite. - WO2009074307 (A2)
Kaufhold, S., Dill, H.G., Dohrmann, R. (2013) Verfahren und Vorrichtung zum Bestimmen eines Mineralanteils eines Tonminerals, insbesondere quellfähigen Tonminerals in einem Gestein (In-situ-Verfahren). - DE-10 2009 017 487.7
