The Determination of Phenolic
Materials in Industrial Wastes
M. B. Ettinger and R. C. Kroner
U. S. Public Health Service
Cincinnati, Ohio
In this consideration of the determination of phenolic materials in
industrial wastes, the discussion will be limited almost entirely to meth¬
ods and procedures which the authors have actually used. No effort will
be made to present an extensive literature survey or to catalogue the
multitude of methods which have been proposed for determining various
phenolic materials. Treatment of the problem from this limited view¬
point will obviously cause much material to go unmentioned. However,
the narrow approach chosen has the advantage of permitting detailed
examination of the techniques treated, and some discussion of the inter¬
pretation of results secured through using those techniques.
To the organic chemist, a phenol is a compound which has at least
one hydroxyl group attached directly to a benzene ring. This defini¬
tion is quite general and inclusive. However, from the standpoint of
the analysis of industrial wastes, such a general definition of a phenol,
or phenolic material, is rarely applied.
It is an operational fact that the definition of phenol for the pur¬
pose of analysis of industrial wastes hinges upon the technique used.
The method selected actually determines what is classed as phenol. In
a particular case, phenol is defined simply as the material recovered
and reported as phenol after the prescribed method has been applied.
From the sanitary standpoint, when a phenol analysis is made on an
industrial waste, it is desired to make collective determination of a
fairly limited part of those compounds which would be classed as phenols
by the organic chemist. The compounds actually desired are mono-
hydric phenols, that is, phenols which include only one hydroxyl group
per benzene ring in their structure. In most cases, it is also desired to
limit the determination to fairly simple phenolic compounds which have
their chemical properties largely dominated by the fact that they include
in their structure a benzene ring substituted by one hydroxyl group.
This group includes materials such as phenol, the cresols, the xylenols,
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