Bridging Heterogeneous Catalysis and Electro-catalysis: Catalytic Reactions Involving Oxygen

Meeting Program — February 2015

Dr. Umit S. Ozkan
Depart­ment of Chem­i­cal and Bio­mol­e­c­u­lar Engi­neer­ing
The Ohio State Uni­ver­si­ty

Umit Ozkan
Cat­alyt­ic reac­tions that involve oxy­gen can be found in a large num­ber of process­es, includ­ing those in ener­gy-relat­ed appli­ca­tions, in emis­sion con­trol and in process­es impor­tant for the chem­i­cal indus­try. Whether the cat­alyt­ic reac­tion is an oxy­gen inser­tion step as in a selec­tive oxi­da­tion reac­tion, or an oxy­gen removal step as in a hydrodeoxy­gena­tion reac­tion, oxy­gen has proven to be a very chal­leng­ing com­po­nent, often deter­min­ing the selec­tiv­i­ty of the reac­tion. Some exam­ples from our lab­o­ra­to­ries that bridge catal­y­sis and elec­tro-catal­y­sis will be dis­cussed, rang­ing from oxida­tive dehy­dro­gena­tion of alka­nes to oxy­gen reduc­tion reac­tion in fuel cells.

Challenges and Advances in Catalytic Fast Pyrolysis of Biomass using Zeolites

Meeting Program — January 2015

Dr. Julia Val­la
Chem­i­cal and Bio­mol­e­c­u­lar Engi­neer­ing Depart­ment
Uni­ver­si­ty of Con­necti­cut, Storrs, CT

Ther­mo­chem­i­cal con­ver­sion of bio­mass to ener­gy, fuels and chem­i­cals is an attrac­tive tech­nol­o­gy for the tran­si­tion from fos­sil resources to a renew­able-based econ­o­my. Cat­alyt­ic Fast Pyrol­y­sis (CFP) of bio­mass is a par­tic­u­lar­ly inter­est­ing tech­nol­o­gy for bio­mass con­ver­sion con­sid­er­ing the already exten­sive infra­struc­ture for hydro­car­bons pro­duc­tion. How­ev­er, many chal­lenges remain unsolved before the deploy­ment of the bio­mass CFP can be real­ized, includ­ing: a) char and coke for­ma­tion, which caus­es rapid cat­a­lyst deac­ti­va­tion; and b) high oxy­gen con­tent in the bio-oil, which makes it incom­pat­i­ble with today’s hydro­car­bon fuels. With respect to the first chal­lenge, it is imper­a­tive to first under­stand the ori­gin and the for­ma­tion of char and coke dur­ing CFP. Con­sid­er­ing the sec­ond chal­lenge, it is impor­tant to under­stand which cat­a­lyst prop­er­ties can enhance the deoxy­gena­tion reac­tions and increase the bio-oil selec­tiv­i­ty to hydro­car­bons. ZSM-5 zeo­lites have been rec­og­nized as one of the most promis­ing zeo­lites for CFP due to their shape selec­tiv­i­ty and their deoxy­gena­tion abil­i­ty. How­ev­er, their micro­p­ore struc­ture can lim­it the acces­si­bil­i­ty of heavy com­pounds to the active sites of their frame­work. Mod­i­fy­ing the zeo­lite pore archi­tec­ture to cre­ate hier­ar­chi­cal struc­tures could pro­vide a solu­tion to this chal­lenge. Fur­ther­more, the CFP process design itself (in situ or ex situ) can alter the prod­uct yield and selec­tiv­i­ty and, thus, the bio-oil qual­i­ty. Dur­ing this pre­sen­ta­tion we will dis­cuss how the zeo­lite prop­er­ties and loca­tion with­in the CFP process (in situ or ex situ) can affect the coke/char for­ma­tion and the deoxy­gena­tion reac­tions for enhanced bio-oil qual­i­ty.
Julia Valla
Iou­lia (Julia) Val­la is an Assis­tant Pro­fes­sor in the Chem­i­cal & Bio­mol­e­c­u­lar Engi­neer­ing Depart­ment at the Uni­ver­si­ty of Con­necti­cut. She received her PhD in the field of the devel­op­ment of new zeo­lites for the decom­po­si­tion of sul­fur com­pounds in naph­tha and the pro­duc­tion of envi­ron­men­tal gaso­line from the Aris­to­tle Uni­ver­si­ty of Thes­sa­loni­ki in Greece. She has served in a lead­er­ship role with Rive Tech­nol­o­gy, Inc. on the com­mer­cial­iza­tion of a nov­el zeo­lite with ordered meso­porous struc­ture for refin­ery appli­ca­tions. Dr. Valla’s research focus­es on the mod­i­fi­ca­tion of zeo­lites struc­ture and their appli­ca­tion in catal­y­sis, adsorp­tion and ener­gy. She is the author/­co-author of 9 papers in peer-reviewed jour­nals, 1 book chap­ter and 2 patents. Dr. Val­la is the recip­i­ent of the Euro­pean Award “RUCADI, Recov­ery and Uti­liza­tion of Car­bon Diox­ide” for her study on the role of CO2 on the reform­ing of nat­ur­al gas for the pro­duc­tion of methanol. At the Uni­ver­si­ty of Con­necti­cut, Dr. Val­la received an award spon­sored by the Nation­al Sci­ence Foun­da­tion for the study “Turn­ing Tars into Ener­gy: Zeo­lites with Hier­ar­chi­cal Pore Struc­ture for the Cat­alyt­ic Removal of Tars”. The study is focused on a nov­el appli­ca­tion of hier­ar­chi­cal­ly struc­tured meso­porous bifunc­tion­al cat­a­lysts for the ther­mo­chem­i­cal upgrad­ing of unde­sir­able tars from bio­mass pyrol­y­sis or gasi­fi­ca­tion to valu­able hydro­car­bons.

Challenges and Solutions in Developing Zeolite Supported Transition Metal Catalysts for Lean-Burn NOx Emission Control

Meeting Program — September 2014

Hai-Ying Chen
Emis­sion Con­trol Tech­nolo­gies
John­son Matthey Inc.
Wayne, PA

Abstract — Reduc­tion of NOx emis­sions from lean-burn engine exhaust has been a main top­ic of envi­ron­men­tal catal­y­sis in the past 20 years. The chal­lenge is the selec­tive con­ver­sion of a low con­cen­tra­tion of NOx (~100 ppm) in the pres­ence of large excess of O2 (~10%). Although zeo­lite sup­port­ed tran­si­tion met­al cat­a­lysts were iden­ti­fied in ear­ly 1990s as promis­ing cat­a­lysts, such a tech­nol­o­gy was not imple­ment­ed till recent­ly.

Ear­ly stud­ies main­ly focused on the devel­op­ment of zeo­lite sup­port­ed tran­si­tion met­al, pri­mar­i­ly Cu and Fe, cat­a­lysts for the selec­tive cat­alyt­ic reduc­tion of NOx with hydro­car­bons (HC-SCR). Even though the HC-SCR tech­nol­o­gy has been con­sid­ered as the “holy grail” of auto­mo­tive catal­y­sis, tech­ni­cal chal­lenges on the activ­i­ty, selec­tive and dura­bil­i­ty of the cat­a­lysts were rec­og­nized to be dif­fi­cult to over­come for the tech­nol­o­gy to be imple­ment­ed into real world appli­ca­tions. How­ev­er, the vast amount of research work, espe­cial­ly the fun­da­men­tal stud­ies on the reac­tion and the cat­a­lyst deac­ti­va­tion mech­a­nisms, demon­strat­ed that the activ­i­ty and selec­tiv­i­ty of this type of cat­a­lysts can be dras­ti­cal­ly improved if an alter­na­tive reduc­tant, NH3, is avail­able in the feed.

Exten­sive inves­ti­ga­tions on the selec­tive cat­alyt­ic reduc­tion of NOx with NH3 (NH3-SCR) began in the mid­dle 2000s aimed to enable diesel pow­ered vehi­cles to meet the US EPA 2007/2010 emis­sion reg­u­la­tions. Both Cu and Fe cat­a­lysts were con­sid­ered. Zeo­lite sup­port­ed Cu SCR cat­a­lysts are more active at low tem­per­a­ture, thus more attrac­tive for appli­ca­tions with low exhaust tem­per­a­ture. The con­ven­tion­al medi­um-pore zeo­lite (10-ring, such as ZSM-5) or large-pore zeo­lite (12-ring, such as beta) sup­port­ed Cu cat­a­lysts, how­ev­er, can­not meet the long-term dura­bil­i­ty require­ments. To over­come this major tech­ni­cal hur­dle, small-pore zeo­lite (8-ring) sup­port­ed Cu cat­a­lysts were invent­ed. On the oth­er hand, zeo­lite sup­port­ed Fe SCR cat­a­lysts are more selec­tive in uti­liz­ing NH3 for NOx reduc­tion at high tem­per­a­tures but show a strong depen­dence on the NO to NO2 ratio in the feed gas at low tem­per­a­tures. Sys­tem approach­es were devel­oped to enhance the low tem­per­a­ture SCR activ­i­ty of the Fe SCR cat­a­lysts. As such, both Cu and Fe SCR cat­a­lysts were suc­cess­ful­ly com­mer­cial­ized and applied on lean-burn diesel vehi­cles meet­ing the strin­gent US EPA 2010 emis­sion stan­dards.

Hai-Ying ChenBiog­ra­phy — Dr. Hai-Ying Chen is a Sci­en­tif­ic and Prod­uct Devel­op­ment Man­ag­er at John­son Matthey, where he leads a team of sci­en­tists to devel­op advanced emis­sion con­trol cat­a­lysts and tech­nolo­gies for both gaso­line engine and diesel engine pow­ered vehi­cles to meet the gov­ern­ment emis­sion reg­u­la­tions.

Dr. Chen received his Ph.D. in Chem­istry from Fudan Uni­ver­si­ty, Chi­na. He has pub­lished more than 50 tech­ni­cal papers in peer-reviewed jour­nals and holds 14 US/international patents. He received the Top Cit­ed Arti­cle Award by Catal­y­sis Today for arti­cles pub­lished in 1998, and was a recip­i­ent of the Amer­i­can Chem­i­cal Soci­ety Award for Team Inno­va­tion in 2009. He was named as the 2014 Her­man Pines Award in Catal­y­sis by the Chica­go Catal­y­sis Club and the 2014 Catal­y­sis Club of Philadel­phia Award by the Catal­y­sis Club of Philadel­phia.

Intrinsic Deactivation in Cobalt-Catalyzed Fischer-Tropsch Synthesis

Meeting Program — April 2014

Gabor Kiss, Stu­art Soled, Chris Kliew­er
Exxon­Mo­bil Res. and Eng. Co.
Annan­dale, NJ

Abstract — In this paper, we describe three intrin­sic deac­ti­va­tion modes observed in exper­i­men­tal cobalt Fis­ch­er-Trop­sch syn­the­sis cat­a­lysts: cobalt oxi­da­tion reversible by mild hydro­gen treat­ment, cobalt agglom­er­a­tion, and cobalt-sup­port mixed oxide for­ma­tion. All three mech­a­nisms involve redox trans­for­ma­tion of the cat­alyt­i­cal­ly active cobalt met­al.
Gabor_KissBiog­ra­phy — Gabor Kiss received his M.Sc. in chem­i­cal engi­neer­ing from the Uni­ver­si­ty of Veszprem (now Pan­non Uni­ver­si­ty), Hun­gary, in 1981. He worked in the Hun­gar­i­an oil indus­try for eight years before enrolling the grad­u­ate school at the Uni­ver­si­ty of Mia­mi. After receiv­ing his Ph.D. in chem­istry in 1993, he accept­ed a posi­tion at Exxon’s (now Exxon­Mo­bil) Cor­po­rate Research Lab­o­ra­to­ries in Clin­ton, NJ, where he is cur­rent­ly a Sr. Sci­en­tif­ic Asso­ciate. His research inter­ests include the kinet­ics, ther­mo­dy­nam­ics, and mech­a­nism of both homo­ge­neous and het­ero­ge­neous cat­alyt­ic process­es. He has pub­lished 26 peer-reviewed papers and has 38 patents.

Explor­ing the Cat­alytic Prop­er­ties of Cu/SSZ-13 using NO Oxi­da­tion and Stan­dard Selec­tive Reduc­tion of NO with NH3

2014 Spring Symposium

Fabio H. Ribeiro*1, W. Nicholas Del­gass1, William F. Schnei­der2, Jef­frey T. Miller3, Alek­sey Yez­erets4, Truno­joyo Anggara2, Christo­pher Paoluc­ci2, Shane A. Bates1, Anuj Ver­ma1, and Atish Parekh1
1School of Chem­i­cal Engi­neer­ing, Pur­due Uni­ver­si­ty, West Lafayette, Indi­ana 47907 (USA)
2Chem­i­cal and Bio­mol­e­c­u­lar Engi­neer­ing, Uni­ver­si­ty of Notre Dame, Notre Dame, Indi­ana
46556 (USA)
3Argonne Nation­al Lab­o­ra­to­ry, Darien, IL 60439 (USA)
4Cum­mins Inc., Colum­bus, IN 47202 (USA)

Abstract — The Cu/SSZ-13 cat­a­lyst (CHA frame­work) is pre­ferred for SCR appli­ca­tions because it shows both SCR per­for­mance and hydrother­mal sta­bil­i­ty. In this work, the site require­ments of the Stan­dard SCR and NO oxi­da­tion reac­tions have been stud­ied on Cu/SSZ-13. Based on an inte­grat­ed exper­i­men­tal and mod­el­ing approach, the active site for the Stan­dard SCR on Cu/SSZ-13 has been assigned to an iso­lat­ed Cu ion locat­ed near the 6 mem­ber rings of SSZ-13, while NO oxi­da­tion required local Cu – O – Cu bonds in the 8 mem­ber cage of SSZ-13. The for­ma­tion of local Cu – O – Cu bonds was a result of sat­u­ra­tion of the num­ber of favor­able Al pairs near the 6 mem­ber ring to sta­bi­lize iso­lat­ed Cu ions. The vari­a­tion of the NO oxi­da­tion and the SCR rates of reac­tion with Cu/Al ratios was thus a cat­alyt­ic con­se­quence of dif­fer­ent Cu ion con­fig­u­ra­tions with­in SSZ-13. The work­ing state of cat­a­lyst under SCR, more­over, was exam­ined by Operan­do X – Ray Absorp­tion Spec­troscopy (XAS). Under reac­tion con­di­tions, the Stan­dard SCR involved a redox mech­a­nism with both Cu(I) and Cu (II) species present. Fur­ther exper­i­ments using operan­do XAS to probe the redox cycle of Cu were car­ried out by remov­ing the oxi­diz­ing half-reac­tion, which pro­duced most­ly the Cu(I) state, and then the reduc­ing half reac­tion, which pro­duced most­ly the Cu(II) state. Thus, any mech­a­nism of Stan­dard SCR has to incor­po­rate a redox cycle. In sum­ma­ry, the stan­dard SCR on Cu-SSZ13 required iso­lat­ed Cu ions to under­go a redox cycle near the 6 mem­ber ring of SSZ13.
Fabio_H_RibeiroBiog­ra­phy — Fabio H. Ribeiro is cur­rent­ly the R. Nor­ris and Eleanor Shreve Pro­fes­sor of Chem­i­cal Engi­neer­ing at the School of Chem­i­cal Engi­neer­ing, Pur­due Uni­ver­si­ty. He received his Ph.D. degree from Stan­ford Uni­ver­si­ty in 1989, held a post-doc­tor­al fel­low­ship at the Uni­ver­si­ty of Cal­i­for­nia – Berke­ley, and was on the Worces­ter Poly­tech­nic Insti­tute fac­ul­ty before join­ing Pur­due Uni­ver­si­ty in August 2003. His research inter­ests con­sist of the kinet­ics of het­ero­ge­neous cat­alyt­ic reac­tions and cat­a­lyst char­ac­ter­i­za­tion by in situ tech­niques. He was Chair for AIChE’s Catal­y­sis and Reac­tion Engi­neer­ing Divi­sion (2010) and is edi­tor for Jour­nal of Catal­y­sis.

Nanoporous Mate­ri­als for Solar Fuel Pro­duc­tion

2014 Spring Symposium

Feng Jiao
Depart­ment of Chem­i­cal and Bio­mol­e­c­u­lar Engi­neer­ing
Uni­ver­si­ty of Delaware
Newark, DE 19716

Abstract — Solar fuel pro­duc­tion is an impor­tant tech­no­log­i­cal chal­lenge, con­sid­er­ing that the ener­gy of sun­light that strikes the earth’s sur­face in an hour is suf­fi­cient to meet our ener­gy demands for a year. Irre­spec­tive of the approach that is pur­sued, oxy­gen evo­lu­tion from water is the crit­i­cal reac­tion, because water is the only cheap, clean and abun­dant source that is capa­ble of com­plet­ing the redox cycle for pro­duc­ing either hydro­gen (from H2O) or car­bona­ceous fuels (from CO2) on a ter­awatt scale. Here, we will show our recent stud­ies in meso­porous spinel sys­tems, which sug­gest the met­al sit­ting at the octa­he­dral site has huge impact on the water oxi­da­tion activ­i­ty of spinel cat­a­lysts. Anoth­er top­ic will be dis­cussed in the pre­sen­ta­tion is the devel­op­ment of selec­tive and robust CO2 reduc­tion elec­tro­cat­a­lyst. We will present a nanoporous Ag elec­tro­cat­a­lyst, which is able to elec­tro­chem­i­cal­ly reduce CO2 to CO with a ~92% selec­tiv­i­ty at a rate (i.e. cur­rent) of over 3000 times high­er than its poly­crys­talline coun­ter­part under a mod­er­ate over­po­ten­tial of less than 0.50 V. Such an excep­tion­al­ly high activ­i­ty is a result of a large elec­tro­chem­i­cal sur­face area (ca. 150 times larg­er) and intrin­si­cal­ly high activ­i­ties (ca. 20 times high­er) com­pared to poly­crys­talline Ag.
Feng_JiaoBiog­ra­phy — Feng Jiao obtained his BS in chem­istry at Fudan Uni­ver­si­ty (2001) and his PhD degree in Chem­istry at Uni­ver­si­ty of St Andrews (Scot­land, 2008), before mov­ing to Lawrence Berke­ley Nation­al Lab­o­ra­to­ry as a post­doc schol­ar. He spent two years in Berke­ley devel­op­ing solar fuel tech­nol­o­gy and joined in the Chem­i­cal and Bio­mol­e­c­u­lar Engi­neer­ing Depart­ment at the Uni­ver­si­ty of Delaware as an assis­tant pro­fes­sor in 2010. He has already pub­lished more than 35 jour­nal papers in lead­ing sci­en­tif­ic jour­nals, such as Nature Com­mu­ni­ca­tions, J. Am. Chem. Soc., and Angew. Chem. Int. Ed. His research activ­i­ties include syn­the­sis of nanoporous mate­ri­als and their poten­tial appli­ca­tions in ener­gy stor­age and con­ver­sion.