Opening address by the president of the Kolloid Gesellschaft Prof H J Schwuger

I would like to welcome you to the 36th General Meeting of the KolloidGesellschaft, in Jülich, and wish you a pleasant stay and very successful scientific discussions. I particularly welcome Dr. Edda Müller, representing the Minister for the Environment, Nature Conservation and Nuclear Safety, and Prof. Dr. Ernst Pöppel, representing the Board of Directors of the Research Centre Jülich.

This year's colloid conference is unique in many respects. It is the first such conference following Germany's reunification. The 1991 General Meeting in Mainz had a special character as a joint meeting with ECIS and, therefore, cannot be regarded as representative.

Interface and colloid chemistry was already at an advanced stage of development in the eastern part of Germany before World War II. This is illustrated by the schools of Leipzig, Dresden, and Berlin which enjoyed worldwide reputation. This reputation was also maintained during the division of Germany, thus strong, synergistic impact may be expected for the future of colloid and surface chemistry in Germany. The significance of interface and colloid chemistry in the new Federal States has been taken into account by the appointment of Hans Sonntag (Berlin) and Hans-Jörg Jacobasch (Dresden) to the Board of the Kolloid-Gesellschaft. We are particularly pleased about the foundation of the Max

Planck Institute for Interface and Colloid Research, which is being established near Potsdam.

Overcoming the division of Germany went hand in hand with overcoming the division of science in East and West. Before World War II, the conferences of the Kolloid-Gesellschaft were always also an opportunity for scientists from East and West to meet each other. I am particularly pleased to welcome scientists from practically all East European countries in addition to our western friends who have regularly presented their papers on these occasions. I hope that the conferences of the KolloidGesellschaft will, in the future continue to be events where scientists from all over the world can meet each other. The fresh start this year is greatly appreciated; we are in a position to welcome nearly 300 representatives from 17 nations. It has been a beneficial tradition of the KolloidGesellschaft to coopt members of other, especially East European associations onto the Board. Following this tradition, we elected Imre Dekäny (University of Szeged), current chairman of the Hungarian Colloid Chemistry Association, to our Board to succeed the late Erwin Wolfram.

We hope that the present situation will give a lasting, strong impetus to the development of interface and colloid chemistry in Germany and Europe.

A further particularity of this , meeting is its topic: "Surfactants and

Opening adress by the president of the Kolloid-Gesellschaft Prof. M. J. Schwuger

Colloids in the Environment." Our special field of research has decisively influenced progess in chemistry and technology in the 19th and 20th centuries. The current industrial society would be inconceivable without this special discipline since surfactants and colloids are of great importance in connection with both everyday products and the latest technologies. Let me just mention detergents, cosmetics, and recording tapes, which have become indispensable in everyday life. The great technological processes of raw material and energy production, of plastics and lacquer fabrication would also be impossible without surfactants and colloids. Their enormous scientific significance is reflected in the production figures. Approximately 5.5 million tons of surfactants were produced last year in the statistically better accessible West European countries, the USA and Japan. Their significance is due to their particular surface-active properties.

Surfactants can reach the environment via different paths, either directly, e.g., in connection with pesticides, or indirectly adsorbed in sewage sludge applied as fertilizer in agriculture. Surfactants are also encountered in rivers and lakes. Apart from synthetic surfactants, nature also produces surface-active substances by biodégradation, and even the human organism daily produces ap-prox. 20 g of surfactants in the form of bile acids.

Various interactions lead to mobilization, remobilization, and immobilization processes for organic and/or inorganic pollutants in nature. These physicochemical processes are vital for keeping our waters and drinking water clean. The soils and sediments are sinks for various chemicals whose penetration into waters must be prevented. Since the extremely hot summer in 1959, when hills of foam primarily consisting of surfactant-protein complexes were formed on our rivers and weirs, attention has been focused on the biodégradation of surfactants. This rather narrow approach must be regarded as too simplifying. It should just be mentioned that the adsorption kinetics or organic pollutants is many times accelerated in the presence of surfactants, and adsorption processes which take one to several weeks can take place within minutes. Such qualitative and quantitative differences clearly show that these processes can take place much more rapidly than would be possible by biodégradation. We therefore consider it our task to combine, for the first time, all the knowledge available in the field of physicochemical interactions in the environment and to indicate future perspectives for the necessary physicochemical investigations in the environment based on the results of our conference.

I wish all participants a fruitful exchange of ideas and thank you for your interest in this highly topical subject.

0 0

Post a comment