Development of a New Biocide

While these regulations are of undoubted benefit to society and the environment at large, the time and costs associated with developing and registering new biocides is often financially prohibitive, much to the detriment of the overall marketplace and the cooling system operator. As a consequence, the water treatment industry has not seen much new or genuinely innovative biocidal technology in many years. There have been some new products, of course [2-(decylthio)ethanamine (DTEA)] is an example and is discussed later in Section 6.3.3], but much of what is currently offered are merely permutations and derivations of chemistries that have been available for perhaps 15 to 20 years or more. 

As a way of overcoming the problems mentioned above, we first created an inclusion complex that was extremely effective in stabilizing Cl-MIT and reducing its irritant properties. [3] However, despite being able to develop the production process commercially, the initial host compound was a halide which was complicated to produce, so it was necessary to develop a new host compound that is less hazardous to the environment and is easy to manufacture. With this aim, we investigated the new hosts that form inclusion complexes with Cl-MIT, using various nonhalide phenol or carboxylic acid compounds which are easily available commercially. We found out that ten types of compound form inclusion complexes with Cl-MIT. We then evaluated the performance of these inclusion complexes, and consequently it became clear that 4,4 -ethylidenebisphenol is the most efficient host. Also, we succeeded in commercially producing a new biocide complex. 

Many of the nonoxidizing biocides employed in cooling systems today were originally developed for other applications, such as slimicides for pulp and paper, biostats for cosmetics, or sanitizers for food factories. The experience gained for these applications has proved to be useful for cooling water systems. Some products that have been available for several years have been, or are being, launched into new and different markets, especially where environmental concerns have a high profile. 

In reconsidering the biocidal properties of organotin compounds, one cannot get away from the conclusion that the biocidal applications are likely to expand strongly in the future, both as a result of an extension of the present possibilities and of the development of new ones. 

This is a relatively new development whereby a biocide is incorporated into a plastic packaging article to prolong or improve the shelf life of the food in the packaging. 

Used by themselves, or in combination with other modem biocides - such as systematic fungicides, bactericides or insecticides - the long-alkyl-chain quaternary ammonium compounds offer a useful tool in the development of new environmentally acceptable wood preservative formulations. The most commonly used quaternary ammonium compounds are coco(fractionated) benzyldimethylammonium chloride and didecyldimethylammonium chloride. 

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