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乙苯在Ｆｅ＿２Ｏ＿３－Ｋ＿２Ｏ催化剂上的ＴＰＤ研究表明，新鲜催化剂表面有α和β两种活性位，均具脱氢、脱乙基和裂解活性．乙苯吸附后能脱氢生成苯乙烯和脱乙基生成苯，若预先吸附水亦可脱甲基生成甲苯，新鲜催化剂表面氧化能力较强，脱下的的氢或烷基会立即与表面晶格氧作用生成Ｈ＿２Ｏ和ＣＯ＿２，并致使催化剂表面被还原产生新的γ活性位．γ位裂解性能较强，但在吸附水后也具有脱氢和脱烷基活性，水对甲苯的生成起着重要的作用，α活性位可能是Ｋ＿２Ｆｅ＿２Ｏ＿４相，β和γ位可能是Ｆｅ＿２Ｏ＿３和Ｆｅ＿３Ｏ＿４（部分还原的氧化铁）相．
The TPD study of ethylbenzene on Fe 2 O 3 -K 2 O catalyst showed that there are two kinds of active sites, α and β, on the surface of fresh catalyst, all of which have dehydrogenation, de-ethyl and cleavage activity. Ethylbenzene can be dehydrogenated into styrene and de-ethyl to form benzene. If pre-adsorbed water can be demethylated to form toluene, the surface of fresh catalyst has strong oxidizing ability. The hydrogen or alkyl group taken off will immediately contact with surface crystal Oxygen generation H_2O and CO_2, and cause the catalyst surface is reduced to produce a new γ-active sites. The γ-site cleavage performance is strong, but it also has dehydrogenation and dealkylation activity after adsorbed water. The formation of toluene on the water plays an important role. The α activity site may be K_2Fe_2O_4 phase, while the β and γ sites may be Fe_2O_3 and Fe_3O_4 (Partially reduced iron oxide) phase.