摘要 |
<p>The present invention provides a process for making diphthaloyl peroxide by reacting phthalic anhydride with aqueous hydrogen peroxide at a pH controlled to between pH 8 and 10, preferably pH 8.8 to 9.2 and a low temperature preferably maintained at 0 DEG to 5 DEG C, and thereafter removing diphthaloyl peroxide from solution, suitably by acidification and filtration. Preferably excess solid phthalic anhydride is employed and is filtered out before the solution is acidified. Desirably the concentration of active oxygen species is maintained at below 0.3 moles/liter.</p> |