Cristian P. Schulthess

Research Interests

The mobility and fate of nutrients and contaminants in soil environments is controlled to a large extent by their affinity to the solid immobile phase relative to their affinity to the liquid (and vapor) mobile phase. My research concentrates on the physical chemical behavior of compounds at the solid-liquid and solid-vapor interface. I am currently investigating (1) the effect of nanopores (small pores inside each individual mineral particle) on the entrapment of organic and inorganic compounds, (2) the enhancement effect of carbon dioxide (CO2) on the adsorption of anions by soil constituents, (3) the adsorption and desorption of CO2 on oxides, and its effect on proton adsorption, (4) the effect of temperature and pressure on the volatility of adsorbed organic compounds, (5) the validity of current methods for the determination of proton adsorption isotherms, with particular emphasis on the impact of background electrolytes, and (6) the competitive adsorption behavior of anions (such as SO4 and SeO4) and organic compounds on oxide surfaces.

Past and present Ph.D. students:

• Karen Kinsela ( Sept. 2003 to present). Soil Chemistry  

  Project: "Manipulation of compost for optimum quality conditions."

  
  
• Hotze Wijnja (Sept. 1995 - Dec. 1999). Soil Chemisty

  Dissertation title: "The interaction of carbonate and organic anions with the adsorption of inorganic anions on hydrous metal oxides." He's now working at The Connecticut Agricultural Experiment Station in New Haven, CT.

Past and present M.S. students:

• Udonna Ndu (Sept. 2004 - present). Environmental Engineering.

  Project: "Adsorption of protons of carbonates on geothite."

• Judy Z. Belek (Sept. 1992 - May 1998). Soil Chemistry. 

  Thesis title: "Adsorption and desorption of aqueous carbon dioxide on a titanium oxide and its effect on proton adsorption." Employed within the Connecticut school system.

• Mary Jane Dapkus (May 1992 - May 1996) Soil Chemistry: Non-thesis, plan B.

  Employed at the Connecticut Department of Environmental. Protection (DEP).

Other non-degree graduate students:

• Wenli Yang (Sept. 2000 - August 2002). Environmental Engineering.

  Project: Impact of nanoporosity on adsorption properties of Fe oxides.

• Zhiqiang Hu (Sept. 1997 - Jan. 1999). Soil Chemisty.
  

  Research topic: "Impact of chloride anions on proton & Se adsorption by an Al oxide."

• Jeffrey S. Quigley (June 1995 - August 1997). Soil Chemisty.

  Research topic: "Effect of bicarbonates on adsorption of anions by Fe oxide."

• Jiang Fu (Sept. 1995 - May 1997). Soil Chemisty.

  Research topic: "Kinetics of adsorption and desorption of bicarbonates on Ti oxide (TiO2) and effects on adsorption of anions."

• Krista Swanson (Sept. 1992 - 1995). Soil Chemisty.

  Research topic: "Effect of bicarbonates on adsorption of protons by an Al oxide (Al2O3)."

Work Experience

Sept. 1997 - present: Associate Professor, UConn.

Jan. 1999 - present: Member of the Institute of Material Sciences (IMS), UConn.

Sept. 1995 - present: Joint Appointment in the Environmental Engineering Program, UConn.

Jan. 1999 - June 1999: Sabbatical Leave:

(1) Porosimetry study of various Fe oxides. Worked with J. Amador and J. Görres at the University of Rhode Island, Kingston, RI.

(2) Universidad Nacional de Cordoba, Cordoba, Argentina. Taught Soil Chemistry (in Spanish), presented seminars, co-advised graduate students at UNC, and discussed research topics with numerous soil chemists in the area.

Oct. 1991 - Aug. 1997: Assistant Professor, UConn.

Mar. 1990 - Sept. 1991: Guest Researcher, National Chemical Laboratory for Industry (now AIST),

Environmental Chemistry Section, Tsukuba, Ibaraki, Japan. Worked with Dr. Shuzo Tokunaga on a Japanese project entitled "Studies on surface reactions on solid particles with the aim of improving properties of arid soils," and on an international STA-NSF collaboration project entitled "The effects of metals on the adsorption of organic compounds by solid particles."

Feb. 1988 - Mar. 1990: Postdoctoral Research Scientist, Oak Ridge National Laboratory,

Environmental Sciences Division, Oak Ridge, TN. Worked on modeling the mobility of natural colloidal organic matter in groundwater with Dr. J.F. McCarthy.

Sept. 1984 - Dec. 1987: University Graduate Research Fellow, University of Delaware,

Department of Plant and Soil Sciences, Newark, DE.

Jan. 1983 - Sept. 1984: Graduate Research Fellow, University of Delaware,

Department of Civil Engineering, Newark, DE.

Nov. 1981 - Sept. 1982: Laboratory Technician, EAWAG (Swiss Federal Institute for Water

Resources and Water Pollution Control), Dübendorf, Switzerland, directed by Dr. Werner Stumm. Worked with Dr. Herbert Hohl and others on a research project involving nucleation.

Mar. 1979 - Aug. 1981: Laboratory Technician and Apprentice, Firmenich, S.A., Geneva,

Switzerland. Worked in organic synthesis, research, and analysis, involving a large spectrum of problems encountered in organic chemistry by the perfume and aromatic industry. Training included use of various instruments and general laboratory working techniques.

Publications

Schulthess, C.P., H. Wijnja and W. Yang. 2002. Oxyanions. p. 548-555. In D. Hillel, C. Rosenzweig, D. Powlson, K. Scow, M. Singer and D. Sparks (eds.) Encyclopedia of soils in the environment. Vol. 1-4. Elsevier, New York.

Wijnja, H., and C.P. Schulthess. 2002. Effect of carbonate on the adsorption of selenate and sulfate on goethite. Soil Sci. Soc. Am. J. 66:1190-1197.

Schulthess, C.P., and Z. Hu. 2001. Impact of chloride anions on proton and selenium adsorption by an aluminum oxide. Soil Sci. Soc. Am. J. 65:710-718.

Wijnja, H., and C.P. Schulthess. 2001. Carbonate adsorption mechanism of goethite studied with ATR-FTIR, DRIFT, and proton coadsorption measurements. Soil Sci. Soc. Am. J. 65:324-330.

Achenie, L., M.A. Butkus, D. Grasso, C.P. Schulthess, T. Morris, and J. Hyde. 2001. A comparative study of neural network and mechanistic models for surface complexation. Advances in Environmental Research 5:137-143.

Görres, J.H., M.A. Stolt, J.A. Amador, C. Schulthess, and P.W. Johnson. 2000. Soil pore manipulations to increase bioaccessible pore volume. p. 755-758. In O. Sililo et al. (ed.) Groundwater: Past achievements and future challenges. A.A. Balkema, Rotterdam, The Netherlands.

Wijnja, H., and C.P. Schulthess. 2000. Vibrational spectroscopy study of selenate and sulfate adsorption mechanisms on Fe and Al hydro(oxide) surfaces. J. Colloid & Interface Sci. 229:286-297.

Wijnja, H., and C. P. Schulthess. 2000. Interaction of carbonate and organic anions with sulfate and selenate adsorption on an Al oxide. Soil Sci. Soc. Am. J. 64:898-908.

Wijnja, H., and C.P. Schulthess. 1999. ATR-FTIR and DRIFT spectroscopy of carbonate species at the aged [gamma]-Al2O3/water interface. Spectrochimica Acta, Part A 55(4):861-872.

Butkus, M.A., D. Grasso, C.P. Schulthess, and H. Wijnja. 1998. Surface complexation modeling of phosphate adsorption by water treatment residual. J. Env. Quality 27:1055-1063.

Schulthess, C.P., and J.Z. Belek. 1998. Proton adsorption on a titanium oxide in the presence of bicarbonate. Soil Sci. Soc. Am. J. 62:348-353.

Schulthess, C.P., K. Swanson, and H. Wijnja. 1998. Proton adsorption on an aluminum oxide in the presence of bicarbonate. Soil Sci. Soc. Am. J. 62:136-141.

Belek, J.Z., and C.P. Schulthess. 1997. Monitoring the desorption of CO2 from a titanium dioxide suspension using a NaOH trap. Soil Sci. 162:10-15.

Schulthess, C.P., J.S. Quigley, M.J. Dapkus, and C.P. Huang. 1997. Are our soil organic extractions too harsh? p. 193-198. In J. Drozd, S.S. Gonet, N. Senesi, and J. Weber (ed.) The role of humic substances in the ecosystem and in environmental protection. Polish Society of Humic Substances, Wroclaw, Poland. (Proceedings of the 8th Meeting of the International Humic Substances Society, 9-14 Sept. 1996, Wroclaw, Poland.)

Schulthess, C.P., and D.K. Dey. 1996. Estimation of Langmuir constants using linear and nonlinear least squares regression analyses. Soil Sci. Soc. Am. J. 60:433-442. (See also Software).

Schulthess, C.P., and S. Tokunaga. 1996. Metal and pH effects on adsorption of poly(vinyl alcohol) by Si oxide. Soil Sci. Soc. Am. J. 60:92-98.

Schulthess, C.P., and S. Tokunaga. 1996. Adsorption isotherms of poly(vinyl alcohol) on Si oxide. Soil Sci. Soc. Am. J.: 60:86-91.

Schulthess, C.P., and D.L. Sparks. 1991. Equilibrium based modeling of chemical sorption on soils and soil constituents. Advances in Soil Science 16:121-163.

Schulthess, C.P., and C.P. Huang. 1991. Humic and fulvic acid adsorption by silicon and aluminum oxide surfaces on clay minerals. Soil Sci. Soc. Am. J. 55:34-42.

Schulthess, C.P., and C.P. Huang. 1990. Adsorption of heavy metals by silicon and aluminum oxide surfaces on clay minerals. Soil Sci. Soc. Am. J. 54:679-688. (Also, letter to the editor: Reply to "Comments on `Adsorption of ...' " SSSAJ (1991) 55:1509-1510).

Schulthess, C.P., and J.F. McCarthy. 1990. Competitive adsorption of aqueous carbonic and acetic acids on an aluminum oxide. Soil Sci. Soc. Am. J. 54:688-694.

Schulthess, C.P., and D.L. Sparks. 1989. Competitive ion exchange behavior on oxides. Soil Sci. Soc. Am. J. 53:366-373.

Schulthess, C.P., and D.L. Sparks. 1988. A critical assessment of surface adsorption models. Soil Sci. Soc. Am. J. 52:92-97.

Schulthess, C.P., and D.L. Sparks. 1987. Two-site model for aluminum oxide with mass balanced competitive pH+salt/salt dependent reactions. Soil Sci. Soc. Am. J. 51:1136-1144.

Schulthess, C.P., and D.L. Sparks. 1986. Backtitration technique for proton isotherm modeling of oxide surfaces. Soil Sci. Soc. Am. J. 50:1406-1411.

3. Published Abstracts

Schulthess, C.P., and M.D. Raigon. 2003. Absorption of alkaline phosphatase enzyme on geothite. Annual Meeting Abstracts - SSSA, Madison , WI.

Yang, W., and C.P. Schulthess. 2002. Entrapment and desorption kinetics of aqueous CO2 on geothite. Annual Meeting Abstracts - SSSA, Indianapolis IN.

Schulthess, C.P., 2000. Soil Chemisty Research Fronts: Past Accomplishments, State-of-the-Art and Future Opportunities. Annual Meeting Abstracts - SSSA, Minneapolis, MN

Schulthess, C.P., J.H. Gorres, and J.A. Amador. 1999. Freeze-thaw impact on the pore structure of goethite. Annual Meeting Abstracts, p. 324, Soil Sci. Soc. of Am., Madison, WI.

Wijnja, H., and C.P. Schulthess. 1999. Raman microspectroscopy of oxyanions adsorbed on metal oxides. Annual Meeting Abstracts, p. 205, Soil Sci. Soc. of Am., Madison, WI.

Wijnja, H., and C.P. Schulthess. 1999. Interactions between anions for adsorption on an Al oxide. 217th American Chemical Society Meeting, Division of Geochemistry, March 21-25, Anaheim, California.

Wijnja, H., and C.P. Schulthess. 1998. Adsorption mechanisms of interactive anions on an Al oxide. Agronomy Abstracts, p. 194, Am. Soc. Agron., Madison, WI.

Wijnja, H., and C.P. Schulthess. 1998. In situ vibrational study of anion adsorption at the oxide-water interface. Agronomy Abstracts, p. 195, Am. Soc. Agron., Madison, WI.

Schulthess, C.P., and H. Wijnja. 1998. Interactive adsorption behavior of anions on an Al oxide. Agronomy Abstracts, p. 195, Am. Soc. Agron., Madison, WI.

Hu, Z., and C.P. Schulthess. 1998. Proton and selenate coadsorption on an Al oxide. Agronomy Abstracts, p. 195, Am. Soc. Agron., Madison, WI.

Wijnja, H., and Schulthess, C. P. 1997. Carbonate adsorption mechanisms at the Al-oxide/solution interface studied by FTIR and electrophoretic mobility. Agronomy Abstracts, p. 182, Am. Soc. Agron., Madison, WI.

Schulthess, C. P., H. Wijnja, and Z. Hu. 1997. Anion and bicarbonate coadsorption on an Al oxide. Agronomy Abstracts, p. 198, Am. Soc. Agron., Madison, WI.

Wijnja, H., and Schulthess, C. P. 1997. ATR/FTIR study of the adsorption mechanism of aqueous carbonate, nitrate, and sulfate on the aluminum oxide-solution interface. 213th American Chemical Society Meeting, Division of Geochemistry, April 13-17, San Francisco, California.

Schulthess, C. P., and D. K. Dey. 1995. A new nonlinear regression of the Langmuir isotherm. Northeast branch of the American Society of Agronomy, June 25-28, Orono, ME. (See also Software).

Schulthess, C. P., and S. Tokunaga. 1992. Adsorption of polyvinyl alcohol on colloidal silicon oxide. 203rd American Chemical Society National Meeting, Division of Environmental Chemistry, p. 745-746, April 5-10, San Francisco, CA.

Schulthess, C. P., and S. Tokunaga. 1991. Adsorption of poly(vinyl alcohol) on colloidal silicon oxide. Proceedings of the 61st Conference of the Chemical Society of Japan, Vol. 2 (in Japanese), p. 678 (abstract in English), Sept. 22-25, Sapporo, Chem. Soc. Japan.

Schulthess, C. P., and S. Tokunaga. 1990. Correlation of the diffuse layer with the suspension effect. Proceedings of the 60th Conference of the Chemical Society of Japan. Vol. 2 (in Japanese), p. 544 (abstract in English), Oct. 2-5, Hiroshima, Chem. Soc. Japan.

Schulthess, C. P., and J. F. McCarthy. 1989. Subsurface transport of contaminants: The role of mobile colloidal particles. (Symposium presentation). 41st Southeast Regional ACS Meeting, Am. Chem. Soc., Winston-Salem, NC.

Schulthess, C. P., and J. F. McCarthy. 1988. Effects of CO2 on adsorption of acetic acid by aluminum oxide. Agronomy Abstracts, p. 204, Am. Soc. Agron., Madison, WI.

Sparks, D. L., and C. P. Schulthess. 1988. Modeling chemical sorption on soils and soil constituents. (Invited paper). Agronomy Abstracts, p. 205, Am. Soc. Agron., Madison, WI.

Schulthess, C. P., and D. L. Sparks. 1987. The backtitration technique and mass balanced modeling of oxide surfaces. 61st Colloid and Surface Science Symposium, Am. Chem. Soc., Ann Arbor, MI.

Schulthess, C. P., and D. L. Sparks. 1986. Na+/Cl- and H+/OH- speciation behavior on an Al-oxide surface. Agronomy Abstracts, p. 172, Am. Soc. Agron., Madison, WI.

Schulthess, C. P., and D. L. Sparks. 1985. Charge Speciation modeling of oxide surfaces using a backtitration technique. Agronomy Abstracts, p. 151, Am. Soc. Agron., Madison, WI.

Software Programs written by Dr. Schulthess

BT (1995): Performs automatic analysis of backtitration data. It helps you identify the end points of the titration curves, plus it will calculate the gamma values for you.

pH-time (1992): Monitors and records pH values as a function of time. It works with an "Accumet 50" pH meter (by Fisher Sci.).

others: Dr. Schulthess has written many software programs for modeling the adsorption of protons, cations, anions, and neutral molecules at the surface-liquid interface. Thus far, all of these programs have been for personal use only.

Personal Information and Trivia

Born: 25 September 1955, Argentina. USA citizen.

Languages:

English and Spanish: fluently read, spoken, and written.

French: very well understood, spoken, and read.

I'm able to read and orally understand various other languages.

August 1981 - November 1981. Swiss Military Service.
Status: First Aid Soldier.

Journal and Society Activities:

• Serve as an invitational reviewer for the Soil Science Society of America Journal (SSSAJ), Journal of Environmental Quality (JEQ), European J. of Soil Science, plus other journals and government agencies.
• January 2002 - present: Associate Editor for the Soil Science Society of America Journal.
• March 6 - 10, 2000: USDA (program 25.0) Panel reviewer of submitted proposals, Washington, D.C.
• 1997 - 2000: member of the SSSA Coordination of Official Methods of Soil Analysis Committee (S889).
• Member of Gamma Sigma Delta since April 1997.
• 1993 - 2002: Connecticut State Chair for the ASA society members.
  
• Received the Editors' Citation for Excellence in Manuscript Review in 1991 by SSSA.
• Presided as Session Chairman in the "Sorption Phenomena in Soils and Soil Constituents" session of the 1989 SSSA meetings in Las Vegas, NV.
• Presided as Session Chariman in the "Soil Chemisty Research Fronts: Past Accomplishments, State-of-the-Art and Future Opportunities" symposium of the 2000 SSSA meetings in Minneapolis, MN.
  
• Presided as Session Chairman in the "Anion Sorption - Desorption - Speciation" session of the 2003 SSSA meetings in Denver, CO.

Mailing Address and E-mail

Last updated: 8 February 2006

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