Meeting Program — March 2018

Manuel Molin­er
Tenured Sci­en­tist, Insti­tu­to de Tec­nología Quími­ca (UPV-CSIC)
Uni­ver­si­dad Politéc­ni­ca de Valen­cia,
Con­se­jo Supe­ri­or de Inves­ti­ga­ciones Cien­tí­fi­cas

Abstract — On the one hand, the prepa­ra­tion of dif­fer­ent zeo­lites, i.e. Beta and ZSM-5, in their nano­sized forms with con­trolled Si/Al molar ratios (~15–30), high sol­id yields (above 90%), and homo­ge­neous crys­tal sizes (~10–25 nm), has been achieved by using sim­ple bifunc­tion­al alkyl-sub­sti­tut­ed mono-cation­ic cyclic ammo­ni­um cations as OSDA mol­e­cules [1]. These OSDAs com­bine a cyclic part and a short alkyl-chain group (pref­er­en­tial­ly C4) and, depend­ing on the size and nature of the cyclic frag­ment, the crys­tal­liza­tion of dif­fer­ent zeo­lites can be con­trolled. The cat­alyt­ic prop­er­ties of the achieved nano­sized zeolitic mate­ri­als have been eval­u­at­ed for the methanol-to-olefins and olefin oligomer­iza­tion reac­tions [1].
On the oth­er hand, the effi­cient syn­the­sis of the small-pore CHA and AEI zeo­lites with nano­sized crys­tals (20—50 nm) has also been obtained fol­low­ing zeo­lite-to-zeo­lite trans­for­ma­tion pro­ce­dures, where high-sil­i­ca FAU mate­ri­als have been used as sil­i­con and alu­minum pre­cur­sors [2]. The nano­sized small pore zeo­lites have been eval­u­at­ed for the methanol-to-olefin reac­tion, observ­ing that their cat­a­lyst life­times are remark­ably longer than the cat­a­lyst life­times observed for con­ven­tion­al small pore zeo­lites. In addi­tion, the selec­tiv­i­ty towards dif­fer­ent light olefins, i.e. propy­lene and/or eth­yl­ene, can be max­i­mized depend­ing on the crys­talline struc­ture of the nano­sized zeo­lites.

Ref­er­ences:

1. (a) E.M. Gal­lego et al., Chem. Sci., 2017, 8, 8138.; (b) M.R. Díaz-Rey et al., ACS Catal., 2017, 7, 6170.
2. N. Martín et al., Chem. Com­mun., 2016, 52, 6072.

Biog­ra­phy — Manuel Molin­er obtained his B.S. degree in Chem­i­cal Engi­neer­ing at the Uni­ver­si­ty of Valen­cia (Spain) in 2003, and com­plet­ed his Ph.D. at the Poly­tech­nic Uni­ver­si­ty of Valen­cia (UPV, Spain), in Chem­istry, under the guid­ance of Prof. Aveli­no Cor­ma in 2008. After­ward, he com­plet­ed a two-year post­doc (2008–2010) with Prof. Mark Davis at the Cal­i­for­nia Insti­tute of Tech­nol­o­gy (Cal­tech, USA).
He is a Tenured Sci­en­tist of the Span­ish Nation­al Research Coun­cil (CSIC) since 2014, where his research lies at the inter­face of het­ero­ge­neous catal­y­sis and mate­ri­als design.
Manuel Molin­er has pub­lished 70 papers in inter­na­tion­al jour­nals, and is co-inven­tor of 24 inter­na­tion­al patents (14 trans­ferred to indus­try). He has received dif­fer­ent nation­al and inter­na­tion­al awards, as the “EFCATS The­sis Award” to the best Ph.D. The­sis in Europe in 2007–2009, the “TR-35 Spain 2011” award­ed by MIT to young tal­ents in Spain under-35, or the “FISOCAT 2014” to young sci­en­tists under 40 in Latin Amer­i­ca.

Meeting Program — February 2018

Dou­glas J. But­trey
Pro­fes­sor of Chem­i­cal and Bio­mol­e­c­u­lar Engi­neer­ing,
Uni­ver­si­ty of Delaware

Abstract — In this pre­sen­ta­tion, I will pay trib­ute to the late Robert K. Gras­sel­li, a tru­ly extra­or­di­nary sci­en­tist who served as a ded­i­cat­ed men­tor to many indus­tri­al sci­en­tists and engi­neers, as well as a num­ber of aca­d­e­mics, such as myself. The pri­ma­ry focus of his research was on improv­ing gen­er­a­tions of com­plex oxide cat­a­lysts for pro­duc­tion of acry­loni­trile by ammox­i­da­tion of propy­lene through much of his career, and of propane in the lat­er years. The Sohio chem­i­cal catal­y­sis group, which Gras­sel­li lead for many years, suc­ceed­ed in devel­op­ing and steadi­ly improv­ing the rev­o­lu­tion­ary SOHIO process for using mul­ti­com­po­nent bis­muth molyb­dates to pro­duce a 50-fold increase in pro­duc­tion of acry­loni­trile, a plat­form chem­i­cal used for mak­ing syn­thet­ic fibers and ABS plas­tics. He became Senior Sci­ence Fel­low at the Sohio Com­pa­ny in Cleve­land, and end­ed his career there in 1985 after about 25 years of ser­vice. This was fol­lowed by 3 years as Direc­tor of the Chem­istry Divi­sion at the Office of Naval Research. From there, he moved to Mobil Research and Devel­op­ment Cor­po­ra­tion in Prince­ton, where he worked until 1995.

Robert Gras­sel­li was induct­ed into the US Nation­al Acad­e­my of Engi­neer­ing in 1995. In 1996, the Sohio acry­loni­trile process was rec­og­nized as the 11th Nation­al His­toric Chem­i­cal Land­mark by the ACS. For this work, Gras­sel­li was admit­ted to the US Engi­neer­ing and Sci­ence Hall of Fame.

Also in 1996, Gras­sel­li became an adjunct pro­fes­sor in the Cen­ter for Cat­alyt­ic Sci­ence and Tech­nol­o­gy at the Uni­ver­si­ty of Delaware; simul­ta­ne­ous­ly, he was appoint­ed as Guest Pro­fes­sor of Phys­i­cal and Cat­alyt­ic Chem­istry at the Uni­ver­si­ty of Munich. He devel­oped a num­ber of col­lab­o­ra­tions through­out the world with William A. God­dard (Cal­Tech), Sir John Meurig Thomas (Cam­bridge), Arne Ander­s­son (Lund), Johannes Lercher (Vien­na and Tri­este), Fer­ruc­cio Tri­firo (Bologne) and many oth­ers, includ­ing myself. I will dis­cuss our col­lab­o­ra­tive work start­ing with the bis­muth molyb­dates begin­ning in 1984 and, from 2002 onward, on the Mo-V-Nb-Te-O bronze “M1” cat­a­lyst for ammox­i­da­tion of propane to acry­loni­trile.

Biog­ra­phy — Dou­glas J. But­trey is a pro­fes­sor of Chem­i­cal and Bio­mol­e­c­u­lar Engi­neer­ing in the Cen­ter for Cat­alyt­ic Sci­ence and Tech­nol­o­gy, with an affil­i­at­ed appoint­ment in Mate­ri­als Sci­ence and Engi­neer­ing, at the Uni­ver­si­ty of Delaware. He received his PhD degree from the Pur­due Uni­ver­si­ty in 1984, and sub­se­quent­ly held the Sohio Post­doc­tor­al Research Fel­low­ship in the Depart­ment of Phys­i­cal Chem­istry at Cam­bridge Uni­ver­si­ty in 1984–85. He was a vis­it­ing assis­tant pro­fes­sor at Pur­due Uni­ver­si­ty with a 3-way joint appoint­ment in the Depart­ment of Chem­istry, Depart­ment of Physics and Astron­o­my, and the School of Mate­ri­als Sci­ence and Engi­neer­ing from 1986–87, before mov­ing to the Uni­ver­si­ty of Delaware. He is the co-author of 100 jour­nal pub­li­ca­tions with over 5,700 cita­tions.

Meeting Program — February 2018

Chao Lin — Stu­dent Speak­er

Abstract — Per­ovskite-sup­port­ed Ni cat­a­lysts were pre­pared by Atom­ic Lay­er Depo­si­tion for use in CO₂ and steam reform­ing of methane. Thin films of CaTiO₃ were grown on MgAl₂O₄ and used as the sup­port. These cat­a­lysts were found to be self-regen­er­at­ing fol­low­ing redox cycling. Activ­i­ties for the ALD-pre­pared cat­a­lysts were high­er than that observed on Ni/MgAl₂O₄ in both steam reform­ing and dry reform­ing. More impor­tant­ly, the per­ovskite-sup­port­ed cat­a­lysts showed min­i­mal cok­ing, even upon expo­sure to dry methane at high tem­per­a­tures.

Meeting Program — January 2018

Jing Lu
Staff Sci­en­tist at Clean Air Divi­sion
John­son Matthey Inc.

Abstract — Cat­alyt­ic oxi­da­tion of methane in the pres­ence of excess of oxy­gen is of great inter­est as a prac­ti­cal tech­nol­o­gy to reduce methane emis­sions from com­pressed nat­ur­al gas vehi­cles, engines, and tur­bines. Typ­i­cal com­mer­cial methane oxi­da­tion cat­a­lysts are alu­mi­na-sup­port­ed pal­la­di­um cat­a­lysts. When oper­at­ed at low tem­per­a­tures, these cat­a­lysts exhib­it rapid deac­ti­va­tions on stream due to water inhi­bi­tion. In addi­tion, these Pd-cat­a­lysts are sen­si­tive to sul­fur poi­son­ing, even with the pres­ence of a trace amount (≤ 1 ppm) of SO₂ in the feed. Among oth­er oxide mate­ri­als, zeo­lites were also inves­ti­gat­ed as a poten­tial sup­port for pal­la­di­um – such as the effects of frame­works and exchange or impreg­na­tion meth­ods – but no sig­nif­i­cant ben­e­fits were dis­cov­ered in the past com­par­ing to con­ven­tion­al alu­mi­na-based cat­a­lysts. Here, we demon­strate the appli­ca­tion of siliceous zeo­lites (i.e. SiO₂-to-Al₂O₃ ratio (SAR) >1200) as Pd-sup­port, the result­ing cat­a­lysts exhib­it sig­nif­i­cant­ly improved activ­i­ty and on-stream dura­bil­i­ty at low tem­per­a­tures, and are able to be regen­er­at­ed from sul­fur poi­son­ing under real­is­tic oper­at­ing con­di­tions.

Biog­ra­phy — Jing Lu received his B.S. degree in Chem­i­cal Engi­neer­ing from Uni­ver­si­ty of Cal­i­for­nia, San­ta Bar­bara. He joined John­son Matthey in 2013 after earn­ing a Ph.D. from Uni­ver­si­ty of Cal­i­for­nia, Davis where he worked with Prof. Bruce Gates. Jing is cur­rent­ly a Staff Sci­en­tist lead­ing the devel­op­ments of selec­tive cat­alyt­ic reduc­tion, ammo­nia slip con­trol and methane oxi­da­tion cat­a­lysts for diesel and nat­ur­al gas aftertreat­ment. He is an inven­tor of sev­er­al patents and author of 19 jour­nal arti­cles.

Meeting Program — November 2017

Alek­sey Yez­erets
Direc­tor of Advanced Chem­i­cal Sys­tems & Inte­gra­tion
Cum­mins Inc.

Abstract — Cu-Zeo­lite SCR cat­a­lysts have emerged in the recent years as the lead­ing tech­nol­o­gy for meet­ing the chal­lenge of NO_x reduc­tion in diesel exhaust. Despite their excel­lent per­for­mance and sta­bil­i­ty char­ac­ter­is­tics, inte­grat­ing this class of cat­a­lysts into an effec­tive and durable exhaust aftertreat­ment sys­tem has proved non-triv­ial. Such sys­tems must be capa­ble of oper­at­ing over a broad range of tran­sient con­di­tions, sur­vive a vari­ety of nom­i­nal and off-nom­i­nal aging expo­sures, and sus­tain their activ­i­ty over many years of active duty. This requires a detailed under­stand­ing of the reac­tion mech­a­nism and deac­ti­va­tion path­ways, and the abil­i­ty to trans­late those into reac­tion engi­neer­ing guid­ance to sys­tem design, feed­back con­trol algo­rithms, and on-board diag­nos­tics. In this pre­sen­ta­tion, we will share exam­ples from our recent find­ings relat­ed to the con­trol­ling regimes of oper­a­tion and to the deac­ti­va­tion mech­a­nisms of Cu-Zeo­lite cat­a­lysts – at the lev­el of cat­a­lyst mate­r­i­al, chem­i­cal func­tions, and over­all emis­sion reduc­tion per­for­mance in the con­text of a sys­tem which con­tains mul­ti­ple cat­alyt­ic ele­ments. We will fur­ther dis­cuss the advance­ments in the abil­i­ty to mod­el the behav­iors of healthy and deac­ti­vat­ed cat­a­lysts, and the respec­tive impli­ca­tions to sys­tem opti­miza­tion and con­trol.

Biog­ra­phy — As Direc­tor of Advanced Chem­i­cal Sys­tems & Inte­gra­tion with Cor­po­rate R&T Divi­sion of Cum­mins Inc., the world’s largest inde­pen­dent man­u­fac­tur­er of diesel engines and relat­ed equip­ment, Dr. Alek­sey (Alex) Yez­erets leads a team of exper­i­men­tal­ists and mod­el­ers respon­si­ble for devel­op­ing an under­stand­ing of the per­for­mance and deac­ti­va­tion of bat­ter­ies, cat­a­lysts, and sen­sors, and for pro­vid­ing guid­ance and sup­port to elec­tri­fied and low-emis­sion prod­ucts at all stages of their life­cy­cles. He also coor­di­nates a port­fo­lio of col­lab­o­ra­tive research pro­grams with indus­tri­al part­ners, Nation­al Labs, and uni­ver­si­ties. He has authored or co-authored 35 patents and 80 peer-reviewed pub­li­ca­tions, with over 2500 total cita­tions. Alex main­tains cur­ren­cy in his field by an active engage­ment in pro­fes­sion­al, edi­to­r­i­al, and grad­u­ate edu­ca­tion activ­i­ties. His tech­ni­cal con­tri­bu­tions have been rec­og­nized by awards from the Catal­y­sis Club of Chica­go, R&D100, ACS, AIChE and SAE, as well as by two Cum­mins Julius Perr awards for inno­va­tion. Alex has been elect­ed an SAE Fel­low.

Meeting Program — October 2017

Anisha Chakrabar­ti — Stu­dent Speak­er

Abstract — The olefin metathe­sis reac­tion was com­mer­cial­ized in the late 1960s to pro­duce eth­yl­ene and 2-butene from propy­lene in the Phillips Tri­olefin Process. The reverse reac­tion, how­ev­er, is cur­rent­ly desired due to a glob­al propy­lene short­age caused by the shift to lighter feed­stocks derived from shale gas frack­ing. Het­ero­ge­neous sup­port­ed MoO_x/Al₂O₃ cat­a­lysts are employed for olefin metathe­sis in the Shell High­er Olefin Process (SHOP) that oper­ates between room tem­per­a­ture and ~200°C.

To probe the mol­e­c­u­lar details of the sup­port­ed MoO_x/Al₂O₃ cat­a­lysts, a mod­ern in situ spec­troscopy approach was under­tak­en. In situ UV-vis mea­sure­ments (Eg val­ues) con­firmed the pres­ence of iso­lat­ed and oligomer­ic MoO_x sur­face sites, with the lat­ter increas­ing with molyb­de­na load­ing. In situ Raman spec­troscopy revealed that at low load­ings of molyb­de­na (1 Mo atoms/nm²), only iso­lat­ed dioxo (O=)₂MoO₂ sur­face sites are present. As the molyb­de­na load­ing is increased (1–4.6 Mo atoms/nm²), oligomer­ic mono-oxo O=MoO₄ sur­face sites co-exist with the iso­lat­ed dioxo (O=)₂MoO₂ sur­face sites. Above mono­lay­er load­ings (>4.6 Mo atoms/nm²), crys­talline MoO₃ nanopar­ti­cles are also present. In situ IR indi­cates that the iso­lat­ed dioxo MoO₄ sites are anchored at more basic HO-μ₁-Al_IV sur­face hydrox­yls, while the sur­face oligomer­ic mono-oxo sites are anchored to more acidic HO-μ_1/3-Al_V/VI sur­face hydrox­yls. Propy­lene metathe­sis at reac­tion con­di­tions sug­gest that the iso­lat­ed dioxo (O=)₂MoO₂ sur­face site may still be present after acti­va­tion of the mono-oxo sur­face sites with propy­lene. In situ UV-vis dur­ing propy­lene metathe­sis indi­cates that Mo⁺⁶ sites are dom­i­nant dur­ing propy­lene metathe­sis due to the pres­ence of unre­duced sur­face dioxo Mo⁺⁶O₄ sites and re-oxi­da­tion of reduced Mo⁺⁴ sites by propy­lene back to Mo⁺⁶=CH₂ and Mo⁺⁶=CHCH₃ reac­tion inter­me­di­ates. The sur­face chem­istry was chem­i­cal­ly probed by C₃H₆-TPSR that ini­tial­ly formed oxy­genat­ed prod­ucts (CH₃CHO, H₂CO, CH₃COCH₃, H₂O and CO/CO₂) dur­ing cat­a­lyst acti­va­tion. The reac­tiv­i­ty of the acti­vat­ed cat­a­lysts to butene pro­gres­sive­ly increased with molyb­de­na load­ing, indi­cat­ing that the oligomer­ic mono-oxo MoO_x sites are much more active than iso­lat­ed dioxo MoO₄ sites for olefin metathe­sis. The crys­talline MoO₃ nanopar­ti­cles, how­ev­er, were found to be inac­tive for metathe­sis. This pre­sen­ta­tion will address the fun­da­men­tal mol­e­c­u­lar and struc­tur­al details of the sup­port­ed MoO_x/Al₂O₃ cat­a­lysts dur­ing propy­lene metathe­sis and estab­lish their struc­ture-activ­i­ty rela­tion­ships.

Meeting Program — October 2017

Jing­guang Chen
Thay­er Lind­s­ley Pro­fes­sor of Chem­i­cal Engi­neer­ing
Colum­bia Uni­ver­si­ty

Abstract — Ris­ing atmos­pher­ic con­cen­tra­tion of CO₂ is fore­cast­ed to have poten­tial­ly dis­as­trous effects on the envi­ro­ment from its role in glob­al warm­ing and ocean acid­i­fi­ca­tion. Con­vert­ing CO₂ into valu­able chem­i­cals and fuels is one of the most prac­ti­cal routes for reduc­ing CO₂ emis­sions while fos­sil fuels con­tin­ue to dom­i­nate the ener­gy sec­tor. The cat­alyt­ic reduc­tion of CO₂ by H₂ can lead to the for­ma­tion of three types of prod­ucts: CO through the reverse water-gas shift (RWGS) reac­tion, methanol via selec­tive hydro­gena­tion, and methane by the metha­na­tion path­way. In the cur­rent talk we will first describe our efforts in con­trol­ling the cat­alyt­ic selec­tiv­i­ty for the three prod­ucts using a com­bi­na­tion of DFT cal­cu­la­tions and sur­face sci­ence stud­ies over sin­gle crys­tal sur­faces, cat­alyt­ic eval­u­a­tion of sup­port­ed cat­a­lysts, and in-situ char­ac­ter­i­za­tion under reac­tion con­di­tions. Next, we will dis­cuss our efforts in con­vert­ing CO₂ with­out using H₂. This is moti­vat­ed by the fact that ~95% of H₂ is gen­er­at­ed from hydro­car­bon-based feed­stocks, pro­duc­ing CO₂ as a byprod­uct. We will present two approach­es to avoid using H₂ for CO₂ con­ver­sion. The first approach involves the uti­liza­tion of light alka­nes, such as ethane, to direct­ly reduce CO₂ via the dry reform­ing path­way to pro­duce syn­the­sis gas (C₂H₆ + 2CO₂ → 4CO + 3H₂) and the oxida­tive dehy­dro­gena­tion route to gen­er­ate eth­yl­ene (C₂H₆ + CO₂ → C₂H₄ + CO + H₂O). The sec­ond approach is the elec­trol­y­sis of CO₂ to pro­duce syn­the­sis gas with con­trolled CO/H₂ ratios. We will con­clude our pre­sen­ta­tion by pro­vid­ing a per­spec­tive on the chal­lenges and oppor­tu­ni­ties in con­vert­ing CO₂ via var­i­ous routes in ther­mo­catal­y­sis and elec­tro­catal­y­sis.

Biog­ra­phy — Jing­guang Chen is the Thay­er Lind­s­ley Pro­fes­sor of chem­i­cal engi­neer­ing at Colum­bia Uni­ver­si­ty, with a joint appoint­ment as a senior chemist at Brookhaven Nation­al Lab­o­ra­to­ry. He received his PhD degree from the Uni­ver­si­ty of Pitts­burgh and then car­ried out his Hum­boldt post­doc­tor­al research in KFA-Julich in Ger­many. After spend­ing sev­er­al years as a staff sci­en­tist at Exxon Cor­po­rate Research, he start­ed his aca­d­e­m­ic career at the Uni­ver­si­ty of Delaware in 1998 and rose to the rank of the Claire LeClaire Pro­fes­sor of chem­i­cal engi­neer­ing and the direc­tor of the Cen­ter for Cat­alyt­ic Sci­ence and Tech­nol­o­gy. He moved to Colum­bia Uni­ver­si­ty in 2012. He is the co-author of 21 US patents and over 340 jour­nal pub­li­ca­tions with over 15,000 cita­tions. He is cur­rent­ly the pres­i­dent of the North Amer­i­can Catal­y­sis Soci­ety (NACS) and an asso­ciate edi­tor of ACS Catal­y­sis. He received many catal­y­sis awards, includ­ing the 2015 George Olah award from ACS and the 2017 Robert Bur­well Lec­ture­ship from NACS.