水热体系下以磷钨酸改性的钯催化剂催化苯酚加氢的研究

发布时间：2018-06-27 17:41

  本文选题：苯酚 + 加氢　； 参考：《昆明理工大学》2016年硕士论文

【摘要】：随着经济社会的不断发展进步,能源的地位也日益重要。其中,化石能源在能源的使用中占据着主导地位。但是伴随着化石能源的使用还将产生大量的污染物,对环境造成不良的影响。随着化石燃料对环境的影响日益加剧,人们的注意力逐步集中在寻找一种合适的、环境友好的、可再生的能源,以取代化石能源在经济社会发展中的作用在生物质能源是研究中面临的主要问题是生物柴油含氧量高、H/C比低,造成这个现象最主要的原因是芳香族化合物的存在以及其难以降解的特性。本研究在实验室之前研究的基础上,选取了苯酚作为模型化合物,探究其了在高温热水(high-temperature water,HTW)系统中苯酚催化加氢。实验过程中对催化剂进行了BET、XRD、XPS、TEM和STEM-ED S表征。表征结果表明制备的磷钨酸改性的Pd/Ce-AlOx催化剂(Pd/W-Ce-AlOx)不仅能够提高主要元素的结合能来提高催化剂的吸电子能力,还能提高苯酚在HTW系统中的加氢效率和选择性。在HTW系统中使用Pd/W-Ce-AlOx催化苯酚加氢反应,当温度较低(180℃)时,反应过程中苯酚的降解率和对环己酮的选择性都很高,环己酮为主要产物且选择性超过95%。然而,当反应温度升高并超过260℃时,水的传质特性的变化使环己酮从催化剂的酸性位点上离开,导致环己酮发生进一步加氢反应生成环己醇甚至是环己烷。根据实验结果,还建立了苯酚在Pd/W-Ce-AlOx催化下发生加氢反应的动力学模型。
[Abstract]:With the development of economy and society, the status of energy is becoming more and more important. Among them, fossil energy plays a leading role in the use of energy. However, the use of fossil energy will also produce a large number of pollutants, which has a negative impact on the environment. With the increasing impact of fossil fuels on the environment, attention is gradually being focused on finding a suitable, environmentally friendly, renewable energy source. In order to replace the role of fossil energy in the economic and social development of biomass energy is the main problem in the study is the high oxygen content of biodiesel low H / C ratio. The main cause of this phenomenon is the presence of aromatic compounds and their difficult to degrade. Based on the pre-laboratory study, phenol was selected as a model compound to investigate the catalytic hydrogenation of phenol in the high-temperature hot water system. The catalyst was characterized by TEM and STEM-ED. The characterization results show that the modified PD / W-Ce-AlOx catalyst (PD / W-Ce-AlOx) can not only increase the binding energy of the main elements to improve the electron absorption ability of the catalyst, but also improve the hydrogenation efficiency and selectivity of phenol in the HTW system. In the HTW system, PD / W-Ce-AlOx was used to catalyze the hydrogenation of phenol. When the temperature was low (180 鈩，

本文编号：2074706