摘要
To better understand the nature of carbon nanotubes supported Co-Mo catalysts （Co-Mo/CNTs） for selective hydrodesulfurization （HDS） of fluid catalytic cracking （FCC） gasoline, studies are carried out using in situ Fourier transform infrared spectroscopy （FT-IR）. The catalytic performances of Co-Mo/CNTs catalysts were evaluated with a mixture of cyclohexane, diisobutylene, cyclohexene, 1-octene （60 ： 30 ： 5 ： 5, volume ratio） and thiophene （0.5%, ratio of total weight） as model compounds to simulate FCC gasoline. The HDS experimental results suggested that the HDS activity and selectivity of Co-Mo/CNTs catalysts were affected by Co/Mo ratio; the optimal Co/Mo atomic ratio is about 0.4, and the optimum reaction temperature is 260 ℃. The in situ FT-IR studies revealed that 1-octene can be completely saturated at 200 ℃. In the FT-IR spectra of diisobutylene, the characteristic absorption peak around 3081 cm^-1 for the stretching vibration peak of =C-H bond was still clear at 320 ℃ indicating that diisobutylene is difficult to be hydrogenated. As for the thiophene, no characteristic absorption peak could be found around 3092 cm^-1 and 835 cm^-1 when the reaction temperature was raised to 280 ℃, indicating that thiophene had been completely hydrodesulfurized. On the basis of FT-IR results, it can be deduced that thiophene HDS reaction occurred mainly through direct hydrogenolysis route, whereas thiophene HDS and diisobutylene hydrogenation reaction over Co-Mo/CNTs catalysts might occur on two different kinds of active sites.
为了更好理解碳 nanotubes 的性质，为液体的选择 hydrodesulfurization (HDS ) 支持了合作瞬间催化剂(Co-Mo/CNTs ) 催化裂开(FCC ) 汽油，研究被执行在 situ Fourier 使用转变红外线的光谱学(英尺红外) 。Co-Mo/CNTs 催化剂的催化表演与环己烷的混合物被评估， diisobutylene， cyclohexene， 1-octene (60:30:5:5，体积比率) 并且 thiophene (0.5% ，全部的重量的比率) 当模型加重模仿 FCC 汽油。HDS 试验性的结果建议 Co-Mo/CNTs 催化剂的 HDS 活动和选择被公司 / 瞬间比率影响；最佳的公司 / 瞬间原子比率是大约 0.4，并且最佳反应温度是在揭示的 situ 英尺红外研究的 260 ° C 那 1-octene 能完全在 200 ° C 被浸透。在 diisobutylene 的英尺红外系列，在为 =C-H 债券的拉长的颤动山峰的 3081 厘米 <sup>−1</sup> 附近的典型吸收山峰在 320 ° C 仍然是清楚的，显示 diisobutylene 是困难的是 hydrogenated。至于 thiophene，当反应温度被提起到 280 ° C 时，没有典型吸收山峰能在 3092 厘米 <sup>−1</sup> 和 835 厘米 <sup>−1</sup> 附近被发现，显示有的那 thiophene 完全水疗院 desulfurized。根据英尺红外结果， thiophene HDS 反应主要通过直接 hydrogenolysis 线路发生了，这能被推出，而在 Co-Mo/CNTs 催化剂上的 thiophene HDS 和 diisobutylene 加氢反应可能发生在活跃地点的二种不同类型上。
基金
National Basic Research Program of China ("973"Program,No.2004CB217807)
