柴油机后喷燃油定向裂解与DOC/CDPF催化燃烧的协同机制研究

围绕柴油机缸内后喷与DOC/CDPF催化技术深度匹配的关键问题，申请人提出了柴油机后喷燃油定向裂解与非均匀DOC/CDPF催化剂设计耦合的新思路，采用综合实验和量子化学计算相结合的方法开展应用基础研究。本项目拟以后喷柴油或其它燃料和非均匀DOC/CDPF催化剂为研究对象，主要内容包括：（1）研究DOC/CDPF活性相位梯度分布的调控机制；（2）后喷燃油碳链热裂解或氧化裂解与重整的影响研究；（3）后喷燃油定向裂解反应途径调控机制；（4）后喷燃油定向裂解与DOC/CDPF催化燃烧协同控制研究。通过原子尺度来测定表面结构以明确催化剂活性形成的本质，研究催化活性相位非均匀分布的调控机制，探究后喷燃油碳氢官能团的裂解和重整演变规律，以及裂解组分在非均匀DOC/CDPF催化剂表面的化学反应路径和机理，建立后喷燃油定向调控与非均匀DOC/CDPF催化系统的构效关系，为实现柴油机近零排放提供基础。

Aiming at the key problem of deep matching between the in-cylinder post-injection and the DOC/CDPF catalytic technology, a novel project was present based upon synergetic the directional cracking of post-injection fuel of diesel engine and the design of he non-uniform DOC/CDPF catalyst system. The researches were carried out with the methods of comprehensive experiments and the quantum chemical calculation. Post-injection fuel or other fuels and non-uniform DOC/CDPF catalysts were taken as the primary research object, and the main objects of the research include four parts as follows：(1) The regulation mechanism of active phase non-uniform distribution in DOC/CDPF catalyst. (2) The influence of thermal cracking or oxidative cracking of the carbon chain of post-injection fuel. (3) The regulation mechanism of reactive pathway of post-injection fuel directional cracking. (4) Investigating the cooperative control of post-injection fuel directional cracking and DOC/CDPF catalytic combustion. Determining the surface structure by atomic scale to clarify the nature of catalyst activity formation, and studying the regulation mechanism of the non-uniform distribution for catalytic active phase. Investigating the evolution of carbon-oxygen functional groups during pyrolysis and thermochemical reaction pathways, and revealing the regulation mechanism of the transition of long-carbon-chain HCs to short carbon chains in the post-injection emissions. Revealing the matching rules between HCs components, DOC heat release, CDPF carbon loading and CDPF regeneration target temperature, and establishing the structure-activity relationship between post-injection fuel directional cracking and DOC/CDPF catalytic system, which will supply a theory foundation for the near zero emission of diesel engine.