Coal fly ash decomposes diethyl phthalate

Decomposition of diethyl phthalate (DEP) exposed to a coal fly ash has been investigated in water by measuring UV-VIS spectra and GC-MS. Alkaline constituents eluted from the fly ash in the liquid phase gradually hydrolyzed DEP to produce monoethyl phthalate and/or phthalic acid. These products were adsorbed on the fly ash and decarboxylated into ethyl benzoate and benzoic acid, respectively, followed by decomposition into benzenes and/or the other compounds of lower molecular weight. The fly ash acts as not only an adsorbent but also a decomposer.