Conversation with Mark Anderson

1987/12/01 Barandiaran, Mariaje Iturria: Elhuyar aldizkaria

At the University of Wisconsin there is a section called "Water Chemistry". In this section, as the name suggests, water studies are conducted. We addressed one of the "professor" in this section to explain what water chemistry is.

Elhuyar – "Water Chemistry" is one of the university departments of Wisconsin. Could you please indicate the department's work area?

Mark Anderson – Water chemistry conducts a study of the solutions and exemptions in which water is the most important solvent. 25 years ago work began in this area as a branch of health chemistry at the University of Wisconsin. Graduate students, master's or doctoral students, work in this section and their origin is varied: Civil engineering, environmental engineering, chemical engineering, geochemistry, soil chemistry and general chemistry.

In addition to the teachers who work there, 22 graduate students currently work in this section called water chemistry.

Initially, this project was organized to study aquatic systems such as lakes and rivers. Currently, work is also being done on the study of heterogeneous systems and other industrial projects.

Water Chemistry House in Madison.
E.- You lead a research team in this department. Could you explain the scope of your group?

M. Anderson– Nere studies the chemistry of colloids, mainly colloids of hydrated oxides of iron, titanium, aluminum and silicon. We study the interface and particle interactions of these systems. All this is applied in the areas of ceramic membranes, forming catalysts, photocatalysts and ceramic sensors.

E. – What technique do you use to advance this task?

M. Anderson– On the one hand we use "in situ" techniques and on the other we use standard techniques. Among the latter, to analyze the load changes that occur on the surface we use electrophoresis and that of the potentiometric platform. To study the size of the particles and their arrangement, quasistatic luminous dispersion and proton correlation spectroscopy are used.

To interpret the chemistry of reactions on the surface we use infrared spectroscopy and cylindrical internal reflection. The microcalorimetry of reaction heat is suitable. Other techniques include X-ray diffraction, electron diffraction, differential thermal analysis and thermogravimetry.

E.– Your group analyzes groundwater pollution. What conclusions have you reached?

M. Anderson – The absorption of micropollutants on the surface of oxides is being studied. These oxides absorb organic and inorganic solutes very well and delay their migration. The mechanisms we have obtained will be used by modelers to predict the behavior of micropulents.

Today we are far from the point where the movement of molecules can be quantitatively predicted. If we can say qualitatively which species will be absorbed on a solid surface. For this we will have to take into account several physical/chemical variables: pH, ionic force and concentration of solute. However, we do not have a quantitative interpretation.

E. – Looking ahead, what plans and projects do you have?

M. Anderson – Our most stimulating field of work is ceramic membranes. We are using particle/particle technology developed by us to form the soles. These suns are gelified in aerogel and xerogel, which form membranes, evolving. By controlling the chemistry of these colloids we can control the size of the pores and the structure of the membrane. These membranes can be used in catalysis, photocatalysis, ultrafiltration, reverse osmosis and microreaction. We believe that we will still dedicate ten more years to this field of work.

E. – As a culmination of this interview I want to ask you a general question. What is the state of the waters in the USA?

M. Anderson – One of the biggest water quality problems we have right now in the US is groundwater pollution. So far we have not worried about the waste disposal and today we are realizing the magnitude of the problem. Discharges in underground tanks, toxic waste discharges and uncontrolled landfills are endangering the quality of our water reserves. These problems must be congested and for this it is necessary to use advanced and sophisticated water washing technologies. Photocatalysis with advanced ceramic membranes can be a suitable technique in the future.