Biological Oxidation of Synthetic
Organic Chemicals
E.  J.  MILLS, JR.,  and  VERNON  T.   STACK,  JR.
Chemist, Chemical Engineer
Process Development Laboratory
Carbide and Carbon Chemicals Company
South Charleston, West Virginia
Investigations by Carbide and Carbon Chemicals of the B.O.D. determination to synthetic organic materials have shown interesting results.
A paper based on the long term B.O.D. data for synthetic organic
materials was presented by Jenkins and Lamb (1) of the Company
at the 1952 Purdue Industrial Waste Conference. From this paper,
and from additional data in the files, it is apparent that the long term
B.O.D. curves, by standard methods, for synthetic organic materials
can be broadly classified into the four types illustrated in Figure 1.
Type I includes the B.O.D. curves for synthetic organic materials
that are readily biologically oxidized. Most synthetic organic materials
are in this classification, and included are the esters, sugars, straight
chain alcohols, and many acids, aldehydes and ketones.
Type II illustrates the B.O.D. curve for synthetic organic materials
that are slow in exerting a B.O.D., and an initial lag period may or
may not exist. Materials in this category include monoisopropanolamine
and butyl CARBITOL acetate.
Type III illustrates the B.O.D. curve for materials that have a
characteristic lag period when sewage seed is used. The extent of the
lag period varies with different synthetic organic materials. In this
category are ethylene glycol, allyl alcohol, ethylene chlorohydrin, diethyl
ketone, pentanedione and CARBITOL.
Type IV includes synthetic organic materials that exert no significant B.O.D. over extended incubation periods. Included in this category are isopropyl ether, diethanolamine, triethanolamine, polyethylene
glycols and morpholine.
If treatment of process effluents containing many different synthetic
organic materials is considered, the effect of specific organic materials
on biological oxidation would be of interest. Considering the types of
B.O.D. curves illustrated in Figure 1, it would be expected that materials exerting a B.O.D. of Type I could be treated readily by biological
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