Surface Bound Biocides — A Novel Possibility to Prevent Biofouling

Abstract

The various types of fouling are classified as biological fouling, chemical reaction fouling, corrosion fouling, freezing fouling, particulate fouling and precipitation fouling (1). Biological fouling or biofouling represents the attachment and metabolism of macroorganisms (macrobial fouling) and/or microorganisms like algae, bacteria and fungi (microbial fouling) on surfaces. It plays a major role in systems, in which the surfaces are in contact with water or aqueous solutions. The hulls of ships, heat exchangers or water tanks are exposed to biofouling deposits. Ion exchange resins or membranes are further examples, where biofouling poses severe problems. Methods of mechanical, physical and chemical nature are used for controlling or preventing biofouling. The most common method is a chemical one, namely chlorination, which is applied periodically or continuously.But this oldest and very effective method, which is also applied in drinking water supply, is not unproblematic, because chlorinated and probably cancerogenic hydrocarbons can be formed. Chlorine may react with ammonia forming hazardous chloramines. Therefore, other chemicals or biocides like ozone or quaternary ammonium compounds were introduced.