It is desirable that a reactor exhibit a self-regulating effect. If this were not true any disturbance to the reactor would result in a continual increase in the magnitude of the disturbance and the reactor would be unstable. In this investigation the reactor is considered to have two reactivity feed-backs: metal temperature and water temperature reactivity effects. These two variables through a metal temperature coefficient and water temperature coefficient determine not only the reactor stability but also determine many operational characteristics.

Potential methods have been examined for the reclamation of high boiler arising from the degradation of polyphenol materials in use as reactor coolants and moderators. To define the chemistry of potential reclamation processes, model polyphenol compounds were used. These include biphenyl, o, m and p-terphenyl, and p-quaterphenyl. Emphasis has been on hydrocracking, redistribution (reaction with benzene), and partial reduction. Preliminary study has been made of the application these techniques to high boiler from Santowax-OM used in the OMRE. The three methods show promise but require detailed investigation to minimize carbon formation to locate optimum operating conditions,.