Science and Technology of Framework Metal-Containing Molecular Sieves Catalysts

2017 Spring Symposium

Las­z­lo Nemeth, Depart­ment of Chem­istry and Bio­chem­istry, Uni­ver­si­ty of Neva­da Las Vegas

Abstract — Since the dis­cov­ery of tita­ni­um sil­i­calite (TS-1) more than 30 years ago frame­work met­al-con­tain­ing mol­e­c­u­lar sieves have become an impor­tant class of cat­a­lyst, find­ing appli­ca­tion in sev­er­al indus­tri­al process­es. Incor­po­ra­tion of tita­ni­um, gal­li­um, iron, tin and oth­er ele­ments into mol­e­c­u­lar sieves frame­works has led to both sci­en­tif­ic progress and engi­neer­ing inno­va­tions in catal­y­sis. As a result of these devel­op­ments, frame­work met­al-con­tain­ing zeo­lites have been imple­ment­ed in the pre­ced­ing decade in new com­mer­cial, byprod­uct-free green process­es, which have improved sus­tain­abil­i­ty in the chem­i­cal indus­try. Based on a com­pre­hen­sive analy­sis of the recent lit­er­a­ture includ­ing patents, this review is a sum­ma­ry of the cur­rent knowl­edge of the sci­ence and tech­nol­o­gy of frame­work met­al-con­tain­ing mol­e­c­u­lar sieves. The syn­the­sis of these mate­ri­als is sum­ma­rized, fol­lowed by an account of state-of-the-art char­ac­ter­i­za­tion meth­ods. The key cat­alyt­ic chemistries, which can be clas­si­fied into oxi­da­tion reac­tions such as olefin epox­i­da­tion, aro­mat­ic hydrox­y­la­tion and ammox­i­ma­tion, and Lewis acid-cat­alyzed reac­tions, are dis­cussed. Mech­a­nisms pro­posed for these trans­for­ma­tions are reviewed, togeth­er with the the­o­ret­i­cal and mod­el­ing tools applied in this con­text. An overview of the com­mer­cial tech­nolo­gies asso­ci­at­ed with the use of frame­work met­al-con­tain­ing mol­e­c­u­lar sieves ( Tita­ni­um and Gal­li­um Mol­e­c­u­lar sieves) mate­ri­als will be pre­sent­ed. The paper will be dis­cuss the cur­rent activ­i­ty on frame­work Tin Beta Zeo­lite, which shown unique “Zeoen­zyme” selec­tiv­i­ties in mul­ti­ple appli­ca­tions. Some new chem­istry using Sn-zeo­lites will be pre­sent­ed also to pro­duce new prod­uct from bio­mass.

Biog­ra­phy — Las­z­lo Nemeth earned a Bachelor’s Degree in Chem­istry and Doc­tor of Sci­ence in chem­i­cal engi­neer­ing from Uni­ver­si­ty of Debre­cen, Hun­gary.

Upon grad­u­a­tion he was assis­tant pro­fes­sor in Depart­ment of Chem­i­cal Tech­nol­o­gy at same Uni­ver­si­ty and lat­er scientist/ man­ag­er at Hun­gar­i­an High Pres­sure Insti­tute, Hun­gary.

UOP invit­ed him to join to Cor­po­rate Research in Des Plaines, IL, He worked for UOP LLC a Hon­ey­well Com­pa­ny 23 years as senior research asso­ciate, with joint appoint­ment as an adjunct pro­fes­sor at Chem­i­cal Engi­neer­ing Depart­ment of Uni­ver­si­ty of Illi­nois at Chica­go.

Dur­ing his research career at UOP he was prin­ci­pal inves­ti­ga­tor of mul­ti­ple suc­cess­ful projects in the area of mate­r­i­al sci­ence, adsorp­tion and catal­y­sis. His exper­tise also includes zeo­lite appli­ca­tion for UOP’s cat­alyt­ic process­es, met­al-zeo­lites, sol­id and liq­uid superacids, hydro­gen per­ox­ide syn­the­sis and new appli­ca­tions.

Las­z­lo joined the Chem­istry and Bio­chem­istry Depart­ment of Uni­ver­si­ty of Neva­da Las Vegas in 2015 as a research pro­fes­sor. Cur­rent­ly he is work­ing on bimetal­lic-zeo­lite syn­the­sis and appli­ca­tions, Lithi­um Ion Bat­tery recir­cu­la­tion, and devel­op new Ther­mochromic nano­ma­te­ri­als.

He spent his sab­bat­i­cal with George Olah (Nobel Lau­re­ate) and Aveli­no Cor­ma (ITQ Spain).

Dr. Nemeth was award­ed with Stein Star award and Honeywell’s excel­lence in Inno­va­tion. He pub­lished 50+ papers and 90+ patents.

Emerging Challenges in Catalysis for Sustainable Production of Transport Fuels: An Industrial View

2017 Spring Symposium

John Shabak­er, BP Group Research, Naperville, IL

Abstract — Pri­ma­ry ener­gy demand has grown tremen­dous­ly over the past cen­tu­ry, and despite the recent eco­nom­ic down­turn, it is pre­dict­ed to increase anoth­er 37% over the peri­od from 2013–20351. Dri­ven by glob­al pop­u­la­tion growth and ris­ing stan­dards of liv­ing, this rapid increase in demand has dri­ven inno­va­tion in the devel­op­ment of new ener­gy sup­plies and high­light­ed envi­ron­men­tal impacts of ener­gy pro­duc­tion & con­sump­tion. In this sem­i­nar, we will explore how these broad changes have in turn affect­ed the trans­porta­tion fuels sec­tor, great­ly influ­enc­ing the price and avail­abil­i­ty of feed­stocks, as well as the desired mix and qual­i­ty of prod­ucts. We will focus on the tech­no­log­i­cal chal­lenges aris­ing for today’s trans­port fuels indus­try, and pro­vide com­men­tary on the role of catal­y­sis research to help address them.

1 BP Ener­gy Out­look 2035 (2017)

Biog­ra­phy — John is cur­rent­ly Tech­nol­o­gy Strate­gist in BP Group Research, where he pro­vides tech­ni­cal input into strate­gic ini­tia­tives across the com­pa­ny.  For­mer­ly, he was US Sci­ence Team Leader in the BP Cen­ter of Excel­lence for Applied Chem­istry & Physics, also part of Group Research that sup­ports busi­ness­es in refin­ing, petro­chem­i­cals, lubri­cants, and upstream pro­duc­tion, as well as man­ages glob­al uni­ver­si­ty pro­grams. From 2007–2011 John led the imple­men­ta­tion of new bio­fu­els path­ways in Refin­ing Tech­nol­o­gy, rang­ing from biobu­tanol process devel­op­ment to renew­able diesel co-pro­cess­ing in refin­ery hydrotreaters.   He was also active in con­ven­tion­al hydropro­cess­ing tech­nol­o­gy, includ­ing pilot plant oper­a­tions and mod­el­ling.

Pri­or to join­ing BP, John was a reac­tion engi­neer­ing spe­cial­ist at Bris­tol-Myers Squibb, apply­ing in-situ spec­troscopy, kinet­ics, and safe­ty stud­ies to phar­ma­ceu­ti­cal process devel­op­ment.  He received his PhD in chem­i­cal engi­neer­ing in 2004 from the Uni­ver­si­ty of Wis­con­sin-Madi­son.  He holds bach­e­lor degrees in chem­i­cal engi­neer­ing and chem­istry from Lehigh Uni­ver­si­ty.

Solid Catalysts Design: From Fundamental Knowledge To Catalytic Application

Meeting Program — April 2017

Professor Avelino Corma
Pro­fes­sor Aveli­no Cor­ma
Pro­fes­sor and founder of the Insti­tu­to de Tec­nología Quími­ca (UPV-CSIC)
Valen­cia, Spain

 

Abstract — The key point in catal­y­sis is to define and syn­the­size the spe­cif­ic active site that will min­i­mize the acti­va­tion ener­gy of the reac­tion, while form­ing selec­tive­ly the desired prod­uct.

In the case of homo­ge­neous catal­y­sis, high­ly selec­tive mol­e­c­u­lar cat­a­lysts can be designed and/or opti­mized from the fun­da­men­tal knowl­edge accu­mu­lat­ed on chem­i­cal reac­tiv­i­ty, and the pos­si­bil­i­ties offered by mol­e­c­u­lar mod­el­ling, in situ or operan­do spec­troscopy, kinet­ics and advanced cat­a­lyst syn­the­sis. Then, when the cat­alyt­i­cal­ly active cen­ters are defined, and their inter­ac­tion with reac­tants and prod­ucts can be ratio­nal­ized, it could, in prin­ci­ple, be pos­si­ble to pre­dict and pre­pare more active and selec­tive cat­a­lysts. In the case of sol­id cat­a­lysts it becomes more dif­fi­cult to define and specif­i­cal­ly build the active sites due to sur­face het­ero­geneities present in most of the solids. Indeed, one should con­sid­er that the pres­ence of non-con­trol­lable sur­face defects and the fact that sur­face recon­struc­tion may occur dur­ing the cat­alyt­ic reac­tion, makes the iden­ti­fi­ca­tion and syn­the­sis of the active sites in sol­id cat­a­lysts a big chal­lenge.

From the point of view of max­i­miz­ing active sites, and since catal­y­sis with solids is a sur­face phe­nom­e­non, high sur­face sol­id cat­a­lysts are most of the times pre­ferred. In this case it is not a sim­ple task to iden­ti­fy the assem­bly of atoms, and there­fore to estab­lish the enthalpy and entropy effects at the inter­face of the sol­id-gas or sol­id-liq­uid, that will be respon­si­ble for the cat­alyt­ic effect at the mol­e­c­u­lar lev­el. More­over, even when the above is achieved, to syn­the­size the solids with well defined, homo­ge­neous sin­gle or mul­ti­ple cat­alyt­i­cal­ly active sites it is a dif­fi­cult task. Notice that reac­tion selec­tiv­i­ty will depend on the capac­i­ty to pre­pare the sol­id avoid­ing the pres­ence of sites oth­er than the desired ones.

It was our objec­tive, since the first moment, to design and syn­the­size sol­id cat­a­lysts in where we could build with­in the struc­ture (almost like in a lego), on the bases of the knowl­edge devel­oped on reac­tion mech­a­nisms, adsorp­tion inter­ac­tions and mate­ri­als syn­the­sis pro­ce­dures, the poten­tial cat­alyt­ic active sites. We expect­ed that, if suc­cess­ful, this could be one way to achieve sol­id cat­a­lysts with well defined, uni­form sin­gle or mul­ti­ple active sites. It also appeared to us that work­ing in that way it should be pos­si­ble to build bridges between the homo­ge­neous and het­ero­ge­neous catal­y­sis. We are aware that in the case of the sol­id cat­a­lysts would not be pos­si­ble to achieve the fine tun­ing of elec­tron­ic, geo­met­ric and chi­ral effects obtained by means of the lig­ands and mol­e­c­u­lar struc­ture, with tran­si­tion met­al com­plex­es, and organ­ic mol­e­cules in homo­ge­neous catal­y­sis. Nev­er­the­less, we attempt­ed to use the sur­face topol­o­gy, tex­tur­al char­ac­ter­is­tics and chem­i­cal com­po­si­tion of the sol­id to mas­ter mol­e­c­u­lar dif­fu­sion and adsorp­tion of reac­tants, while select­ing one among the dif­fer­ent pos­si­ble tran­si­tion states.

We will present what has been our evo­lu­tion on the design of three types of sol­id cat­a­lysts in where we fol­lowed the method­ol­o­gy describe above. They are:

  1. High sur­face area hybrid organ­ic-inor­gan­ic cat­a­lysts in where we attempt to reg­u­late the char­ac­ter­is­tics of the active sites and the geo­met­ri­cal flex­i­bil­i­ty to max­i­mize dis­per­sion forces.
  2. Ful­ly inor­gan­ic high­ly ther­mi­cal­ly sta­ble micro and meso­porous mate­ri­als with well defined sin­gle sites, while con­trol­ling mol­e­c­u­lar dif­fu­sion and adsorp­tion to achieve remark­able selec­tiv­i­ty effects.
  3. Gen­er­at­ing and sta­bi­liz­ing from sin­gle met­al atoms to clus­ters with a few atoms to nanopar­ti­cles, with reac­tiv­i­ties so high that remind those of enz­imes.

We will show that by fol­low­ing the method­ol­o­gy: “under­stand­ing for design­ing and syn­the­siz­ing”, we could also achieve what it is always a desir­able objec­tive in catal­y­sis: “Design­ing for indus­tri­al appli­ca­tion”.

Biog­ra­phy — Aveli­no Cor­ma, Pro­fes­sor and founder of the Insti­tu­to de Tec­nología Quími­ca (CSIC-UPV) in Valen­cia (Spain), he has been car­ry­ing out research in het­ero­ge­neous catal­y­sis in acad­e­mia and in col­lab­o­ra­tion with com­pa­nies for near­ly 35 years. He has worked on fun­da­men­tal aspects of acid-base and redox catal­y­sis with the aim of under­stand­ing the nature of the active sites, and reac­tion mech­a­nisms. With these bases has devel­oped cat­a­lysts that are being used com­mer­cial­ly in sev­er­al indus­tri­al process­es. He is an inter­na­tion­al­ly rec­og­nized expert in sol­id acid and bifunc­tion­al cat­a­lysts for oil refin­ing, petro­chem­istry and chem­i­cal process, espe­cial­ly in the syn­the­sis and appli­ca­tion of zeo­lite cat­a­lysts. He has pub­lished more than 900 research papers, and inven­tor on more than 130 patents. Cor­ma earned his BS in Chem­istry at Valen­cia Uni­ver­si­ty, PhD at Madrid under direc­tion of Prof. Anto­nio Cortes, and spent two years post­doc at Queen ́s Uni­ver­si­ty. He has received the Dupont Award on “Mate­ri­als Sci­ence”, Cia­pet­ta and Houdry Awards of the North Amer­i­can Catal­y­sis Soci­ety, the F. Gault Award of the Euro­pean Catal­y­sis Soci­ety, the M. Boudart Award on Catal­y­sis by the North Amer­i­can and Euro­pean Catal­y­sis Soci­eties, the G. J. Somor­jai ACS Award on Cre­ative Catal­y­sis, the Breck Award of the Inter­na­tion­al Zeo­lite Asso­ci­a­tion, the Nation­al Award of Sci­ence and tech­nol­o­gy of Spain, “Rey Jaume I” Prize for New Tech­nolo­gies (2000), the ENI
Award on Hydro­car­bon Chem­istry, the Roy­al Soci­ety of Chem­istry Cen­te­nary Prize, Solvay Pierre-Gilles de Gennes Prize for Sci­ence and Indus­try and Gold Medal for the Chem­istry Research Career 2001–2010 in Spain, La Grande Médaille de l’Académie des sci­ences de France 2011 and Hon­our Medal to the Inven­tion from the Fun­dación Gar­cía Cabreri­zo in Spain. Gold Medal Foro QUÍMICA y SOCIEDAD to all his research career, Gran Medaille of the Sci­ence French Acad­e­my, Edith Flani­gen Lec­ture­ship, East­man Lec­ture, Direc­tor ́s Dis­tin­guished Lec­ture Series Pacif­ic North­west Nation­al Lab­o­ra­to­ry ́s. Prince of Asturias Award for Sci­ence & Tech­nol­o­gy 2014, 48th W. N. Lacey Lec­ture­ship in Chem­i­cal Engi­neer­ing-Cal­tech (2015) and The Jacobus van ‘t Hoff Lec­ture 2015 at TU Delft Process Tech­nol­o­gy Insti­tute (2015), The Hoyt C. Hot­tel Lec­tur­er in Chem­i­cal Engi­neer­ing at MIT Chem­i­cal Engi­neer­ing Depart­ment (2015), J.T. Don­ald Lec­ture series 2015–2016 at McGill Uni­ver­si­ty, Spiers Memo­r­i­al Award RSC (2016), IZA Award of the Inter­na­tion­al Zeo­lite Asso­ci­a­tion (2016), George C.A. Schuit Award lec­ture at the Uni­ver­si­ty of Delaware (2016).

Doc­tor Hon­oris Causa” by Utrecht Uni­ver­si­ty (2006), UNED (2008), München Tech­no­log­i­cal Uni­ver­si­ty (2008), Uni­ver­si­dad Jaime I de Castel­lón (2008), Uni­ver­si­dad de Valen­cia (2009), Bochüm Uni­ver­si­ty (2010), Uni­ver­si­dad de Ali­cante (2010), Ottawa Uni­ver­si­ty (2012) Delft Tech­no­log­i­cal Uni­ver­si­ty (2013) Jilin Uni­ver­si­ty (Chi­na) (2013), Uni­ver­si­ty of Bucarest (2014), Jaen (2016), Cantabria (2016).

Parallel between UOP’s Reforming and Dehydrogenation Technologies and Catalysts

Meeting Program — March 2017

Manuela Serban
Manuela Ser­ban
Prin­ci­pal Research Sci­en­tist,
Hon­ey­well UOP

 

Abstract — With sig­nif­i­cant expe­ri­ence in Con­tin­u­ous Cat­a­lyst Regen­er­a­tion (CCR) reform­ing tech­nol­o­gy, i.e., Plat­form­ing™ process, Honeywell’s UOP was unique­ly posi­tioned to invent, devel­op and com­mer­cial­ize 25 years ago, a CCR-type light paraf­fins dehy­dro­gena­tion tech­nol­o­gy, i.e., Ole­flex™ process, lever­ag­ing on the Plat­form­ing tech­nol­o­gy. These two tech­nolo­gies rep­re­sent two of UOP’s core tech­nolo­gies and togeth­er with their cat­a­lysts, are being con­tin­u­ous­ly improved and opti­mized to max­i­mize end-user prof­itabil­i­ty. Cur­rent­ly there are 300+ CCR Plat­form­ing units and 25+ Ole­flex units oper­at­ing world­wide, with more in con­struc­tion or in com­mis­sion. This pre­sen­ta­tion will high­light sim­i­lar­i­ties and dif­fer­ences between the Plat­form­ing and Ole­flex tech­nolo­gies and cat­a­lysts. We will dis­cuss the chem­i­cal and phys­i­cal require­ments and prop­er­ties for the two types of cat­a­lysts, the main cat­a­lysts deac­ti­va­tion routes, and high­light some of UOP’s char­ac­ter­i­za­tion tools and exper­tise used to devel­op new reform­ing and dehy­dro­gena­tion cat­a­lysts and diag­nose dif­fer­ent symp­toms relat­ed to aged com­mer­cial cat­a­lysts.

Biog­ra­phy — Manuela Ser­ban is a Prin­ci­pal Research Sci­en­tist in the Olefins and Deter­gents Devel­op­ment Group lead­ing teams respon­si­ble for the devel­op­ment of new Ole­flex cat­a­lyst gen­er­a­tions. Manuela has over 12 years of expe­ri­ence with UOP, includ­ing reform­ing tech­nol­o­gy and cat­a­lysts, cat­alyt­ic hydrodesul­fu­r­iza­tion, flue gas desul­fu­r­iza­tion for coal gasi­fi­ca­tion plants, break­through liq­uid fuels decon­t­a­m­i­na­tion tech­niques. She is the author of sev­er­al arti­cles in peer reviewed Chem­i­cal Engi­neer­ing jour­nals and has 38 US patents. She has a PhD in Chem­i­cal Engi­neer­ing from Worces­ter Poly­tech­nic Insti­tute and post-doc­tor­al expe­ri­ence at Argonne Nation­al Lab­o­ra­to­ry.

Biomass and Natural Gas Valorization by Zeolite Catalysis

Meeting Program — February 2017

Raul Lobo
Raul Lobo
Claire D. LeClaire pro­fes­sor of Chem­i­cal and Bio­mol­e­c­u­lar Engi­neer­ing,
Uni­ver­si­ty of Delaware

 

Abstract — Prof. Lobo’s research group is inter­est­ed in devel­op­ing and under­stand­ing catal­y­sis sys­tems to enable the trans­for­ma­tion abun­dant, inex­pen­sive and—when possible—renewable car­bon sources into feed­stocks for the chem­i­cal indus­try. We com­bine exper­tise in mate­ri­als syn­the­sis, catal­y­sis and kinet­ics, and reac­tion engi­neer­ing to devel­op nov­el cat­a­lysts and cat­alyt­ic process­es that pro­duce valu­able prod­ucts.

In the first part I will focus on C-C bond form­ing reac­tions that are help­ful in the trans­for­ma­tion of furans (pro­duced from glu­cose or xylose by dehy­dra­tion) into valu­able com­mod­i­ty chem­i­cals. To this end we have devel­oped and opti­mized zeo­lite cat­a­lyst com­po­si­tions to form aro­mat­ic species out of the furans via Diels-Alder reac­tions and Friedel-Craft acy­la­tion reac­tions. We will describe efforts to pro­duc­ing ben­zoic acid and α-methyl­styrene from furans in high selec­tiv­i­ty and high yield, along with the elu­ci­da­tion of the reac­tion mech­a­nisms of these reac­tions.

In the sec­ond part I will dis­cuss on-going research direct­ed towards the devel­op­ment of cat­a­lysts for the selec­tive oxi­da­tion of methane into methanol. We will show that zeo­lites can serve as hosts of tran­si­tion met­als oxide clus­ters (cop­per or iron) that are anal­o­gous to met­al oxide clus­ters observed in a num­ber of impor­tant enzymes such as par­tic­u­late methane monooxy­ge­nase (pMMO). These clus­ters are capa­ble of oxi­diz­ing methane to methanol, car­bon monox­ide and CO2. By selec­tive­ly choos­ing mate­ri­als that com­part­men­tal­ize Cu-O clus­ters, we have iden­ti­fied zeo­lite struc­tures that are able to selec­tive­ly oxi­dize methane to methanol with very high selec­tiv­i­ty in a three-step cyclic process. We will describe the poten­tial and the draw­backs of trans­form­ing such cyclic process into a cat­alyt­ic process for methanol pro­duc­tion.

Despite the matu­ri­ty of the field of catal­y­sis this talk will show that tan­ta­liz­ing new oppor­tu­ni­ties emerge from the dis­cov­ery of new cat­a­lyst struc­tures and com­po­si­tions, and from improve­ments in our con­trol of the com­po­si­tion of met­al clus­ters in nanoscop­ic envi­ron­ments.

Biog­ra­phy — Raul F. Lobo is the Claire D. LeClaire pro­fes­sor of Chem­i­cal and Bio­mol­e­c­u­lar Engi­neer­ing at the Uni­ver­si­ty of Delaware and Direc­tor of the Cen­ter for Cat­alyt­ic Sci­ence and Tech­nol­o­gy. His research inter­ests span the devel­op­ment of nov­el porous mate­ri­als for catal­y­sis and sep­a­ra­tions, the chem­istry of zeo­lites, catal­y­sis for ener­gy and the envi­ron­ment, and the sci­en­tif­ic aspects of cat­a­lyst syn­the­sis. He has pub­lished over one hun­dred fifty ref­er­eed reports and he is co-inven­tor in three US patents. He obtained his under­grad­u­ate degree in Chem­i­cal Engi­neer­ing at the Uni­ver­si­ty of Cos­ta Rica in 1989 and lat­er moved to Cal­i­for­nia to pur­sue grad­u­ate stud­ies in Chem­i­cal Engi­neer­ing at Cal­tech. He worked for one year at Los Alam­os Nation­al Lab­o­ra­to­ry, New Mex­i­co as a post­doc­tor­al fel­low and he start­ed his aca­d­e­m­ic career at the Uni­ver­si­ty of Delaware in 1995.

Prof. Lobo has con­duct­ed research in the use of zeo­lites for nitrogen/oxygen sep­a­ra­tions, and car­bon diox­ide sep­a­ra­tions from flue gas­es. He has con­tributed to the fun­da­men­tals of zeo­lite nucle­ation and crys­tal growth and to the appli­ca­tion of zeo­lites for a num­ber of cat­alyt­ic appli­ca­tions. In par­tic­u­lar his group research helped under­stand the mech­a­nisms of reac­tion and sta­bil­i­ty of zeo­lite cat­a­lysts used for the removal of NOx gas­es from com­bus­tion exhaust, devel­oped cat­alyt­ic mate­ri­als for the trans­for­ma­tion of bio­mass-derived furans into com­mod­i­ty aro­mat­ic mol­e­cules such as xylenes and ben­zoic acid and dis­cov­ered mate­ri­als for the selec­tive acti­va­tion of methane using cop­per oxide clus­ters.

Ciapetta Award Lecture: Novel Zeolite Catalysts for Diesel Emission Applications

Meeting Program — January 2017

Ahmad Moini
Ahmad Moi­ni
BASF Cor­po­ra­tion

 

Abstract — Auto­mo­tive exhaust con­di­tions present unique chal­lenges for the design of effec­tive cat­a­lysts. In addi­tion to the need for cat­alyt­ic activ­i­ty over a wide tem­per­a­ture range, the cat­a­lyst must show dura­bil­i­ty towards extreme hydrother­mal aging con­di­tions. The use of zeolitic mate­ri­als under such con­di­tions is espe­cial­ly chal­leng­ing due to the vul­ner­a­bil­i­ty of zeo­lites to steam aging. The BASF dis­cov­ery of the Cu-CHA cat­a­lyst for selec­tive cat­alyt­ic reduc­tion (SCR) of NOx demon­strat­ed an effec­tive bal­ance between favor­able active sites and zeo­lite frame­work dura­bil­i­ty. It also paved the way for the imple­men­ta­tion of urea SCR as the key approach for NOx reduc­tion in diesel vehi­cles. This pre­sen­ta­tion will high­light the devel­op­ment of Cu-CHA as the lead­ing tech­nol­o­gy for diesel emis­sion appli­ca­tions. Spe­cif­ic focus will be placed on the syn­the­sis and struc­tur­al fea­tures of the zeo­lite. In addi­tion, there will be a dis­cus­sion of spe­cif­ic char­ac­ter­i­za­tion and mod­el­ing approach­es focus­ing on the unique attrib­ut­es of the met­al active sites and the inter­ac­tion of these met­al species with the zeo­lite frame­work.

Biog­ra­phy — Dr. Ahmad Moi­ni is a Research Fel­low at BASF Cor­po­ra­tion in Iselin, NJ. He obtained his Ph.D. in Chem­istry from Texas A&M Uni­ver­si­ty, and held a post­doc­tor­al appoint­ment at Michi­gan State Uni­ver­si­ty. Dr. Moi­ni start­ed his career at Mobil Research & Devel­op­ment Cor­po­ra­tion (now Exxon­Mo­bil), where he con­duct­ed research on micro­p­orous mate­ri­als. With a focus on explorato­ry zeo­lite syn­the­sis, he stud­ied the mech­a­nism of zeo­lite crys­tal­liza­tion and the role of spe­cif­ic class­es of organ­ic direct­ing agents in the for­ma­tion of var­i­ous zeo­lite frame­works. He joined Engel­hard Cor­po­ra­tion (now BASF) in 1996. Since then, his pri­ma­ry research inter­ests have been in the area of mate­ri­als syn­the­sis, direct­ed at a range of cat­alyt­ic and func­tion­al appli­ca­tions. He applied high through­put meth­ods for the syn­the­sis and eval­u­a­tion of cat­alyt­ic mate­ri­als, and used these tools for the devel­op­ment of new prod­ucts. A sig­nif­i­cant part of his work has been direct­ed towards cat­a­lysts for envi­ron­men­tal appli­ca­tions. These efforts, in col­lab­o­ra­tion with the extend­ed BASF team, led to the dis­cov­ery and devel­op­ment of Cu-CHA cat­a­lyst for selec­tive cat­alyt­ic reduc­tion (SCR) of NOx from diesel vehi­cles. He holds 48 US patents relat­ing to var­i­ous aspects of mate­ri­als and cat­a­lyst devel­op­ment.

Unraveling Catalytic Mechanisms and Kinetics: Lessons from Electrical Networks

Meeting Program — November 2016

Ravindra Datta
Pro­fes­sor Ravin­dra Dat­ta
Pro­fes­sor in the Depart­ment of Chem­i­cal Engi­neer­ing,
Fuel Cell Cen­ter,
Worch­ester Poly­tech­nic Insti­tute

 

Abstract — Cat­alyt­ic reac­tion net­works, in gen­er­al, com­prise of mul­ti­ple steps and path­ways. While one can now read­i­ly pre­dict kinet­ics of these mol­e­c­u­lar steps from first prin­ci­ples, there is not yet avail­able a com­pre­hen­sive frame­work for: 1) visu­al­iz­ing and ana­lyz­ing these reac­tion net­works in their full com­plex­i­ty; and 2) unequiv­o­cal­ly iden­ti­fy­ing the ger­mane steps and path­ways.

Thus, we have devel­oped an approach called the “Reac­tion Route (RR) Graph” approach, which allows: 1) direct enu­mer­a­tion of all the path­ways as walks on the RR Graph; 2) ther­mo­dy­nam­ic con­sis­tence of step kinet­ics; 3) elu­ci­da­tion of dom­i­nant path­ways that con­tribute mate­ri­al­ly to the over­all flux; 4) iden­ti­fi­ca­tion of bot­tle­neck steps in each of these path­ways; and 5) devel­op­ment of explic­it rate laws based on the elec­tri­cal anal­o­gy.

The elec­tri­cal net­work anal­o­gy is based on two aspects of RR Graphs, name­ly: 1) qua­si-steady state (QSS) mass bal­ance of inter­me­di­ate species, the equiv­a­lent of the Kirchhoff’s Cur­rent Law (KCL) of elec­tri­cal cir­cuits; and 2) Hess’s law, or ther­mo­dy­nam­ic con­sis­tence, the equiv­a­lent of the Kirchhoff’s Poten­tial Law (KPL), which makes RR Graphs pre­cise­ly equiv­a­lent to elec­tri­cal net­works. Fur­ther, we define the step resis­tance in terms of step kinet­ics to make the anal­o­gy com­plete. The approach is described with the help of the water-gas shift exam­ple.

Biog­ra­phy — Ravi Dat­ta is Pro­fes­sor of Chem­i­cal Engi­neer­ing and Direc­tor of WPI Fuel Cell Cen­ter. He obtained his Ph.D. degree from the Uni­ver­si­ty of Cal­i­for­nia, San­ta Bar­bara, in 1981. From then until 1998, he was a Pro­fes­sor of Chem­i­cal Engi­neer­ing at the Uni­ver­si­ty of Iowa, when he moved to WPI, and served as Chem­i­cal Engi­neer­ing Depart­ment Head until 2005. Ravi’s research is focused on cat­alyt­ic and elec­tro­cat­alyt­ic reac­tion engi­neer­ing of Clean Ener­gy, includ­ing, fuel cells, hydro­gen, renew­able fuels, nov­el cat­a­lysts, and cat­alyt­ic reac­tion net­works. He is a coau­thor of 150 papers and 8 patents, and has been a men­tor to 25 doc­tor­al stu­dents.