2014 Spring Symposium
Aleksey Yezerets, Neal Currier, Krishna Kamasamudram, Junhui Li, Hongmei An, Ashok Kumar, Jinyong Luo, Saurabh Joshi
Abstract – A diverse spectrum of highly capable diesel catalytic emission control systems has emerged in the recent years, in response to stringent environmental regulations in several leading world markets. By taking the brunt of the emission reduction, these highly effective systems allowed the engines to be designed and tuned for maximum fuel efficiency and minimum CO2 emissions.
Unlike their gasoline emission control predecessors, diesel systems include multiple catalysts with distinct functions, along with a variety of sensors and actuators, thus representing veritable chemical plants. For example, the emission control system commercialized in Cummins-powered 2010 heavy-duty diesel vehicles includes four distinct catalytic devices, a diesel oxidation catalyst (DOC), catalyzed diesel particulate filter (DPF), selective catalytic reduction (SCR) catalyst, and an ammonia slip selective oxidation catalyst (ASC). The system further includes eight sensors, and two fluid injectors, along with the respective controls and diagnostic algorithms. Another system, commercialized by Cummins in 2007 and 2010 Dodge Ram pickups, is based on a NOx adsorber catalyst and represents similar level of sophistication. Underlying the system-level complexity is the intricacy of the individual catalytic elements, some of which include multiple distinct chemical functions and complex topology.
Predictably, lifecycles of such systems are shaped by the behaviors of the individual catalytic elements and their interactions. These often feature a variety of reversible processes, in response to deposition and removal of various poisons and masking agents, reversible chemical and morphological changes, along with irreversible degradation, often referred to as aging.
In this presentation, we will review several examples of interactions between catalysts in the context of the above diesel emission control systems, emphasizing how the recent advances in their practical application were underpinned by the developments in the broader field of heterogeneous catalysis and reaction engineering.
Biography – At Cummins, the world’s largest independent manufacturer of diesel engines and related equipment, Dr. Yezerets leads an R&D team responsible for guidance and support of emission control products at all stages of their lifecycle, and coordinates a portfolio of collaborative research programs with National Labs, universities and industrial partners. Dr. Yezerets serves on the Editorial Board of the Journal of Applied Catalysis B: Environmental, has acted as a guest editor of three issues of the Catalysis Today Journal, and organized a number of environmental catalysis sessions in industrial and academic meetings. He has received 11 US patents, published over 50 peer-reviewed articles, as well as presented numerous invited, keynote, and award lectures. Dr. Yezerets has a special appointment to the Graduate Faculty of Chemical Engineering at Purdue University. His contributions to the field of catalytic emission control were recognized by the Herman Pines Award in Catalysis, R&D 100 Award, national awards by the American Chemical Society, American Institute of Chemical Engineers, and Society Automotive Engineering, as well as Julius Perr Award for Innovation by Cummins.