I found this in US patent 2,692,271.
Column 3 lines 6-32:
Although peracids generally may be emplyed as epoxidizing agents,
it will be found, as a practical matter, that peracetic acid will
be the epoxidizing agent generally employed, and that acid has
been used throughout the examples given hereinafter. The peracetic
acid may be effectively prepared by reacting acetic acid with aqueous
hydrogen peroxide in the presence of about 1% sulfuric acid as a
reaction catalyst. The reaction proceeds with glacial acetic acid
or aqueous acetic acid. The hydrogen peroxide may be the commercial
27.5% or 100 volume product or may be aqueous solutions of high
peroxide content as, for instance, 50% to 90% H2O2. Peracetic acid
may similarly be prepared by reaction of acetic anhydride with hydrogen
peroxide by oxidation of aldehydes, U.S. patent 2,314,385, or by the
method described in U.S. patent 2,490,800 issued December 13, 1949,
to Greenspan.
When employing the resultant peracetic acid as the epoxidizing agent,
it is necessary to neutralize any strong acid, e. g. sulfuric acid,
present as catalyst from its formation. This may be done either by
neutralizing the sulfuric acid content with an alkali, such as caustic
soda, or by buffering the solution with a material such as sodium
acetate.
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Edited by Nutmeg238 6/20/00.
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Manual of Patent Examining Procedure
Chapter 100
103 Right of Public to Inspect Patent Files and Some
Application Files
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