Electrochemical talk with Toribio Fernández

1989/03/01 Irazabalbeitia, Inaki - kimikaria eta zientzia-dibulgatzaileaElhuyar Fundazioa Iturria: Elhuyar aldizkaria

The Faculty of Chemical Sciences of Donostia is very young. It began fourteen years ago in the house Joan XXIII, next to the cemetery of Altza, and for three years it has been in a new and functional house on the campus of Ibaeta. Being a new faculty with a small number of students, the University of the Basque Country is leading the way in research. The study focuses on the field of polymers or plastics and with the aim of knowing what the local electrochemistry team is, we have come to its director, Toribio Fernández. We then transcribe the words of this friendly man born on the mountain of Leon.

Elh.- Can you explain the history of the electrochemical group?

Toribio Fernández, head of the Electrochemistry Group at the Faculty of Chemistry of San Sebastian.

Toribio Fernández.- History has had many ups and downs. As you know, there are common incidents in the new faculties.

I am an electrochemical of study, but when I came to the faculty, polymer research began, which is the main specialty taught in this faculty. Then we had no great resources. However, around 1981 Roca Solana of Madrid left us a couple of potentiostats and we started working with these tools. We worked on polymerizations initiated with redox couples and thought that instead of using redox pairs we could use electrodes. So we started working on electropolymerization.

On the other hand, my training has been related to corrosion and since being in Euskal Herria there was no group studying corrosion, we thought we should also investigate corrosion. In addition, in this way our research would be more related to the demands and needs of the social environment. Therefore, we began to analyze corrosion by 1982.

Elh.- How many people are currently working as a team?

T.F.- In the team we are working about twelve people. Nine or ten faculties and others in INASMET and LABEIN. With these two centers we have a close scientific relationship.

Elh.- What kind of research do you do: theoretical or practical?

T.F.- It is a theoretical research that we do, but that uses a very practical perspective. The work we are developing with INASMET and LABEIN is aimed at technological processes of great practical interest. The implementation of practical processes of industrial interest requires a theoretical training that is carried out here in the faculty. The practical part is done in INASMET and LABEIN.

Elh.- What are the lines of research developed by your team?

T.F.- There are two main lines: the electrochemical generation of polymers (we are the only group in the State that works systematically in this type of work) and corrosion. In the field of basic research and in the field of electrochemical generation of polymers, it is intended to know the formation of these polymers, the process that occurs at the interface between the electrode and the solution. Sometimes the polymer forms in dissolution, in others non-polymeric products are formed on the surface of the electrode and in others. What rules?

Working in the electrochemistry laboratory.

We want to know that. The discovery that appears in the literature is empirical; certain solvents and electrolytes are to be placed and the conclusion is the same. We want to know why and then apply it to solve practical problems. We work on the creation of non-conductive polymers. With them we intend to overcome the electrodeposition processes that are currently used to protect cars. These methods provide automotive anti-corrosion procedures with a warranty of between 8 and 10 years. We want to create on-site polymer films on metal.

Another branch of great current in electropolymerization is that of the conductive polymers. When we started in this field five years ago, it was not fashionable. Conductive polymers can have great applications in the future: anti-radar paints, new chemical and biological sensors, new light batteries, new electrocatalysts, microelectronics, etc.

We are developing new electrochemical methods to help make rapid decisions in the corrosion industry. I mean the industrialist comes to me saying that he has to buy new tanks for the transport of triocylic acid and that they offer two different types of steel and that he wants to know which one is the most suitable. We are able to answer through tests in ten minutes. In your case you will be indicated the most convenient type of steel.

Elh.- You are also working on biocorrosion, right?

T.F.- Yes, and these processes have a great interest. Depending on the environment in which bacteria live, they can produce products that can lead to highly localized corrosion processes. Bacteria, on the other hand, can generate corrosion processes that deteriorate any structure at a long distance. The bacteria that reduce sulfate is a good example and through an anaerobic process create sulfide in environments with high organic content. The rotten egg odor present in some streams, sewers and marshes is due to the anaerobic reduction performed by bacteria.

To see the damage these bacteria can cause, take the case of Pasaia Bay. Contamination by the cause of the bins is high and therefore high sulphide concentration. The cooling water taken by the Lezo thermal power plant from Pasaia Bay has a high concentration of sulphides and holes are formed in the new heat exchangers for two or three days. The new heat exchanger is not protected by the sulfur layer like the old ones. Therefore, the old exchangers behave like cathodes and the new one behaves like anode, drilling in a few days.

We try to simulate the bacterial process by electrochemical methods and we are developing rapid tests to know the behavior of the materials in different conditions. If we did bacterial cultures to achieve this goal, it would take 15-20 days to reach the same conclusion. We want to achieve the conclusion by means of an adequate and concise electrochemical procedure, that is, to know the behavior of the material.

Microscope eyepieces.

This is a very attractive topic. In fact, there are thousands of bacteria that depending on the environment can alter metabolism, resulting in metal structures and substances that attack plastics.

Fdo.- As we have been able to verify, they have signed an agreement with the Provincial Council of Gipuzkoa for the study of the drinking waters. What work do you have to do?

T.F.- We have to do a very nice study about the corrosiveness of water supplies in the province. All the potable waters are different from the physical-chemical point of view and also act differently. Copper, galvanized steel, mild steel and cast steel have been tested in reservoirs and tanks and their corrosion behavior is analyzed based on weight loss. In addition, we will develop procedures to simulate in laboratory what happens in nature through electrochemical processes. We want to develop quick methods to simulate in laboratory the attack that will suffer tests immersed in the water for three years. What is the goal? So when from the City Council or from the Provincial Council tell us that they want to use a new material in their water supply system, among all the offers you can know the best of corrosion.

Elh.- What is your project with LABEIN?

T.F.- We are conducting together with LABEIN an environmental corrosion study. They are making technological and practical development and we draw scientific conclusions. In this work we have already done several doctoral theses.

Steels, aluminum, copper, etc. we are studying the corrosion that occurs when left in the air. The final objective of this study is the realization of a corrosion map of the Basque Country that determines the corrosive effect of the different types of atmosphere of the Basque Country. This has been done in other peoples.

Elh.- It doesn't seem very easy to do that job. The situation of the atmosphere in one place depends on many variable factors.

T.F.- That's the key. We have installed between 10 and 12 measuring stations in different urban and rural atmospheres. We have developed a mathematical-statistical method of data processing and have obtained a first theoretical approach. From there and depending on the parameters of each place, we can know the corrosive kinetics of a certain type of steel. Subsequently, using this statistical model and introducing data on pollution, meteorology and other data from different places in the Basque Country, we can obtain the theoretical corrosion of the Basque Country.

Polypirrol obtained at constant current intensity and anodic oxidation.

This has been done in many places. This method for our case does not seem very reliable to me. In the other population there are prevailing winds or the climatology is very definite, but in ours it does not exist. Studies on the situation in Bilbao have shown that this situation is not repeated anywhere else in Europe. That is why at least 60-70 measuring stations should be installed in the Basque Country for the study of corrosion and the simultaneous realization of corrosion maps in situ.

Another project with LABEIN is the study of the corrosion status of the steel concrete reinforcement.

Elh.- Previously mentioned also INASMET. What do you do with them?

T.F.- With INASMET we are working on corrosion. The truth is that collaboration has cost a lot. They work the technical aspect and we the scientist. Their views and our views are totally different, but the need to link them in some way has been very positive. They have encouraged us to use parameters of immediate technological interest in basic research and we, from a scientific point of view, have provided them with information that has been useful to solve technological problems.

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I believe that collaboration with these centers is very positive and very positive, since they do not have the scientific vision we have and we do not have the ability to give immediate response to technological problems, so the joint work of both parties can bear fruit.

Elh.- Where do you get grants to carry out your work?

T.F.- We get from different sources of funding: The sources are the University of the Basque Country, the Basque Government, CAICYT (now General Directorate of Scientific and Technical Research) and the Provincial Council of Gipuzkoa. However, the greatest help (even if it is not competition in its power) is received from the Provincial Council of Gipuzkoa and other groups working in the Faculty. In my opinion, it is to thank deeply the commitment of the Provincial Council of Gipuzkoa to promote research.

Elh.- Do they have any relationship with other research centers outside INASMET and LABEIN?

Polythiophene coated metal.

T.F.- We are working with other groups of the University of the Basque Country. For example, with the Faculty of Computer Science. From the point of view of corrosion we are working on the treatment of images. A microscope analyzes the surface of the metal and stores the images obtained. Computer scientists are developing a program that will decide to what extent the surface is attacked with these images.

On the other hand, we have close relations with other State centers such as the Roca Solano Institute, the National Center for Metallurgical Research, the University of Santiago de Compostela and the Autonomous University of Madrid. Our laboratory people work several days a year in these centers to work or exchange ideas with new techniques such as tunnel effect microscopy.

We also send the members of the group outside the State to see that the level of research done in it is equivalent to what we do and to the value of their work. At the European level we have close relations with the University of Paris 7 and the University of Southampton. We are about to start relations with South American universities.

Elh.- Do you want to end with something else?

T.F.- I think it is important to highlight the work being done in the centers of the University of the Basque Country, and especially in the Faculty of Chemistry of San Sebastian, in research. Maybe people on the street don't know about it and we, the researchers, are the most guilty, because we don't know how to expose what we do. I think the remarkable work being done here in the Faculty labs is that we have to teach people, that we owe them an explanation (as we use public money). I also want to thank Elhuyar for the opportunity to bring our work to light.