多孔碳负载NiO-MOx(M=Ce, La)新型结构催化剂可控设计合成及其催化丙烷氧化脱氢反应研究

Propylene production via dehydrogenation of propane is one of the best ways for its utilizations, connecting non-petroleum resources to traditional petrochemical industry. Among the several dehydrogenation routes, oxidative dehydrogenation (ODH) can be operated at lower temperature and is not equilibrium limited. Traditional supported nickel catalyst has been widely considered as a promising catalyst for the ODH of propane at low temperature. However, to overcome the barrier of the trade-off between the catalytic activity and the selectivity of propylene has become the focus of catalysis. This proposed work is to construct NiO-MOx@C (M=Ce, La) nano-catalysts and to study the controllable synthesis and function manipulation of the nano-catalysts. The intrinsic properties of nitrogen-containing porous carbon will be employed to disperse coordinatively and confine the NiO-MOx species to improve the degree of dispersion and increase the amount of active sites and stability. Meanwhile, the basic property of La2O3 and formation of Ce-La-O solid solution will be applied to enhance desorption rate of propylene, thus improving the selectivity of propylene. Furthermore, in-situ characterization techniques are also used to investigate multi-sites synergistic mechanism and the relation between catalyst structures and catalytic performance of ODH of propane. A breakthrough in the novel catalyst construction and the catalytic performance manipulation will be expected. The research results will provide scientific guidance to the development of novel ODH catalysts.

将价格低廉且资源丰富的丙烷脱氢转化为经济价值高的丙烯是自然资源高效利用的最佳途径之一。丙烷氧化脱氢具有热力学有利和催化剂不易失活等优点。负载型镍基催化剂是丙烷低温氧化脱氢较为理想的催化剂，但丙烯选择性和催化活性无法同时提高成为制约丙烷氧化脱氢技术的瓶颈，也是亟待克服的研究重点和难点。本项目采用我们新发明的糖-尿素-盐无水体系原位合成多孔碳负载氧化物专利技术，一步构建多孔碳负载NiO-MOx（M=Ce, La）催化材料，利用其特殊的含氮多孔碳前驱体载体络合分散并限域NiO-MOx物种，提高分散度和活性位数量以提高催化活性。进一步利用氧化镧的碱性以及镧铈固溶体的共同作用促进丙烯脱附以提高丙烯选择性。在此基础上利用原位动态光谱表征等手段，研究催化剂多中心协同机制及其与丙烷氧化脱氢的构效关系，预期在新催化材料构建和产物选择性调控机制等方面取得突破，为丙烷氧化脱氢新型高效催化剂的开发提供科学指导。

将价格低廉且资源丰富的丙烷脱氢转化为经济价值高的丙烯是自然资源高效利用的最佳途径之一。丙烷氧化脱氢具有热力学有利和催化剂不易失活等优点。负载型镍基催化剂是丙烷低温氧化脱氢较为理想的催化剂，但丙烯选择性和催化活性无法同时提高成为制约丙烷氧化脱氢技术的瓶颈，也是亟待克服的研究重点和难点。在本项目中，由于我们设计的催化剂碳材料的强度不够以及由于制备方法导致的孔结构不可控制，因此在丙烷氧化脱氢反应条件下，并未能发挥应有的效果，因此我们把重点放在多中心催化协同催化剂的开发上，采用我们新发明的糖-尿素-盐无水体系一步法和共沸精馏法开展了以下几方面的研究：(1)多孔碳负载新型结构催化剂的原位一步合成及其用于催化加氢脱硫和肉桂醛选择加氢反应;（2）共沸精馏法制备分子筛限域金属催化剂用于催化对硝基苯酚加氢反应;（3）氧化镧负载贵金属Pd催化剂的合成及其用于催化肉桂醛选择加氢反应;（4）二氧化硅限域金属镍催化剂的原位合成及其用于催化肉桂醛选择加氢反应。在项目执行期内，本团队成员及时调整思路，很好的完成了预期的目标，包括高性能脱硫催化剂多孔碳负载硫化物的开发，高稳定性限域分子筛的合成以及氧化物形貌效应等等。本项目过程中在Applied Catalysis A: General、Applied Clay Science、Chemical Physics Letters、RSC Advances等期刊上发表论文9篇，培养已毕业硕士研究生4名。