Makoto Takada*, Shin Taniguchi**, Akihiko Murakami** and Masaaki Hosomi**

* Center for Environmental Engineering, EBARA RESEARCH Co., Ltd.
** Dep. of Chemical Engineering, Tokyo University of Agri. and Tech.

+ Correspondence should be addressed to Makoto Takada:
(2-1 Honfujisawa, 4-chome, Fujisawa-shi, 251 Japan)

Abstract

Polychlorinated biphenyls (PCBs) were found to cause a liver disorder, so their production and use was banned and the possession of them becoming obsolete is now mandatory. However, the result of holding such equipment over a long period of time was that containers became more and more time worn with an increased danger of PCB leakage. These are reasons why prompt establishment of a technique that can detoxify PCBs is desired. The Base Catalyzed Decomposition (BCD) process is based on the formation of hydrogen radicals through a liquid phase dehydrogenation reaction. Hydrogen radicals generated from hydrogen donor substitute chlorine atoms of PCBs and PCBs become non-toxic biphenyl. To establish the BCD process, this report examines the rate-limiting factors that are considered to influence reaction rate. This was done to obtain findings for determining the optimum reaction conditions, as well as examine the reaction products to ascertain the complete dechlorination. The dechlorination reaction by BCD process could be assumed as a first-order reaction and the activated energy was obtained. It was confirmed that the amount of sodium hydroxide being added has an influence on the reaction rate. One hundred percent dechlorination was confirmed by a quantitative analysis of inorganic chlorine as a reaction product.

Key words: base catalyzed decomposition process, dehydrogenation reaction, dechlorination reaction, hydrogen donor, rate constant