在300 m L加氢试验装置上进行加氢稳定试验,考察了反应压力对煤直接液化循环溶剂性质的影响,并通过0.5 L高压釜煤液化试验,考察了煤在不同加氢深度循环溶剂中的液化效果。结果表明,随着溶剂加氢反应压力的升高,循环溶剂密度、黏度及氮...在300 m L加氢试验装置上进行加氢稳定试验,考察了反应压力对煤直接液化循环溶剂性质的影响,并通过0.5 L高压釜煤液化试验,考察了煤在不同加氢深度循环溶剂中的液化效果。结果表明,随着溶剂加氢反应压力的升高,循环溶剂密度、黏度及氮含量递减,氢碳原子比及供氢指数递增,循环溶剂性质得到改善,供氢性能得到提高,从而促进煤的转化率和油收率提高。当加氢反应压力由12.5 MPa升至19.3 MPa时,煤的转化率从87.21%提高到88.40%,液化油收率从51.62%提高到55.58%。展开更多
Five Co-B amorphous alloy catalysts were prepared by chemical reduction in different media, including pure water and pure ethanol as well as the mixture of ethanol and water with variable ethanol content, Their cataly...Five Co-B amorphous alloy catalysts were prepared by chemical reduction in different media, including pure water and pure ethanol as well as the mixture of ethanol and water with variable ethanol content, Their catalytic properties were evaluated using liquid phase furfural hydrogenation to furfuryl alcohol as the probe reaction. It was found that the reaction media had no significant influence on either the amorphous structure of the Co-B catalyst or the electronic interaction between metallic Co and alloying B. This could successfully account for the fact that all the as-prepared Co-B catalysts exhibited almost the same selectivity to furfuryl alcohol and the same activity per surface area （ Rs ）, which could be considered as the intrinsic activity, since the nature of active sites remained unchanged. However, the activity per gram of Co （ R^mH ） of the as-prepared Co-B catalysts increased rapidly when the ethanol content in the water-ethanol mixture used as the reaction medium for catalyst preparation increased. This could be attributed to the rapid increase in the surface area possibly owing to the presence of more oxidized boron species which could serve as a support for dispersing the Co-B amorphous alloy particles.展开更多
This study shows that minor amount of water plays a very important role in solvent-free hydrogenation of halogenated nitrobenzenes. For dried sponge Pd, the reaction cannot occur in the absence of water. For Pd/C cata...This study shows that minor amount of water plays a very important role in solvent-free hydrogenation of halogenated nitrobenzenes. For dried sponge Pd, the reaction cannot occur in the absence of water. For Pd/C catalyst, minor amount of water reduces the induction time, increases the reaction rate and reaction TOFs. Water might enhance the diffusion, adsorption and dissociation of H2 on Pd catalysts.展开更多
文摘Five Co-B amorphous alloy catalysts were prepared by chemical reduction in different media, including pure water and pure ethanol as well as the mixture of ethanol and water with variable ethanol content, Their catalytic properties were evaluated using liquid phase furfural hydrogenation to furfuryl alcohol as the probe reaction. It was found that the reaction media had no significant influence on either the amorphous structure of the Co-B catalyst or the electronic interaction between metallic Co and alloying B. This could successfully account for the fact that all the as-prepared Co-B catalysts exhibited almost the same selectivity to furfuryl alcohol and the same activity per surface area （ Rs ）, which could be considered as the intrinsic activity, since the nature of active sites remained unchanged. However, the activity per gram of Co （ R^mH ） of the as-prepared Co-B catalysts increased rapidly when the ethanol content in the water-ethanol mixture used as the reaction medium for catalyst preparation increased. This could be attributed to the rapid increase in the surface area possibly owing to the presence of more oxidized boron species which could serve as a support for dispersing the Co-B amorphous alloy particles.
基金supported by the National Natural Science Foundation of China(Nos.20976164,21176221 and 21136001)National Basic Research Program of China(973 Program)(Nos. 2011CB710803,2013CB733500)Zhejiang Provincial Natural Science Foundation of China(No.LY12B03005)
文摘This study shows that minor amount of water plays a very important role in solvent-free hydrogenation of halogenated nitrobenzenes. For dried sponge Pd, the reaction cannot occur in the absence of water. For Pd/C catalyst, minor amount of water reduces the induction time, increases the reaction rate and reaction TOFs. Water might enhance the diffusion, adsorption and dissociation of H2 on Pd catalysts.
