Poly(ethylene terephthalate) (PET) was pyrolyzed in the presence of several metal hydroxides for the high-yielding recovery of benzene in one benzene-rich fraction. The highest benzene yield of 80.7% and a purity of 90.2 wt % were achieved in the presence of Ca(OH)(2) and Ba(OH)(2), respectively. In addition, thermogravimetric mass spectroscopic (TG-MS) measurements of metal terephthalates as the benzene precursors suggested a mechanism of benzene formation from metal terephthalates.