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研究了活性炭负载的Ｆｅ 催化剂在乙苯脱氢与逆水煤气变换偶合反应中的催化活性，考察了催化剂中的铁物相，添加Ｌｉ， Ｎａ 和Ｋ 等碱金属以及ＣＯ２ 对催化活性的影响． 实验表明，Ｆｅ３Ｏ４ 可能是偶合反应的活性相． 在ＣＯ２气氛中，适当还原度的、经碱金属元素调变后的Ｆｅ／ＡＣ的催化活性较好，苯乙烯的选择性明显提高． 以ＮＨ３ 和ＣＯ２为探针分子，运用微分吸附量热技术表征了催化剂的表面酸碱性质． 结果表明，活性炭表面具有较多的弱酸位． 担载铁后，ＮＨ３ 的起始吸附热为９６ ｋＪ／ｍｏｌ， 吸附饱和覆盖度为１１２ μｍｏｌ／ｇ， 说明Ｆｅ／ＡＣ表面具有酸性；ＣＯ２ 的起始吸附热为７２ ｋＪ／ｍｏｌ， 吸附饱和覆盖度为７ μｍｏｌ／ｇ， 表明催化剂表面也有少量的碱位． 碱金属元素的加入减弱了Ｆｅ／ＡＣ催化剂表面上的酸强度，同时产生了一定量的碱性位，因而显著提高了苯乙烯的选择性．ＣＯ２ 的作用是及时除去脱氢反应产生的Ｈ２ ， 促进乙苯脱氢生成苯乙烯，并抑制乙苯的加氢裂解．
The catalytic activity of Fe supported on activated carbon in the coupling reactions of ethylbenzene dehydrogenation and counter-water gas shift conversion was investigated. The effects of iron phase, addition of alkali metals such as Li, Na and K and CO2 on the catalytic activity were investigated. Experiments show that, Fe3O4 may be the coupling reaction of the active phase. In CO2 atmosphere, the catalytic activity of Fe / AC modified by alkali metal element with proper reduction degree is better, and the selectivity of styrene is obviously improved. Using NH3 and CO2 as probe molecules, the surface acid-base properties of the catalysts were characterized by differential adsorption calorimetry. The results show that the surface of activated carbon has more weak acid sites. The initial adsorption heat of NH3 was 96 kJ / mol and the saturated adsorption coverage was 112 μmol / g after iron was loaded, indicating that the surface of Fe / AC was acidic. The initial adsorption heat of CO2 was 72 kJ / mol, Degree of 7 μmol / g, indicating that the catalyst surface also has a small amount of base. The addition of alkali metals weakens the acid strength on the surface of the Fe / AC catalyst and at the same time produces a certain amount of basic sites, thereby significantly increasing the selectivity of styrene. The role of CO2 is the timely removal of H2 generated by the dehydrogenation reaction, promote the dehydrogenation of ethylbenzene to styrene, and inhibit the hydrocracking of ethylbenzene.