Life Cycle of Cat­alytic Diesel Emis­sion Con­trol Sys­tems

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.
Aleksey_YezeretsBiog­ra­phy — 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.