Author Archives: Vlad Nikolakis

Mixed Protonic-Electronic Membrane Reactors; Converting Hydrocarbon Resources and CO2 to Fuels


Prof. Eric D. Wachs­man
Direc­tor, Mary­land Ener­gy Inno­va­tion Insti­tute
William L. Crentz Cen­ten­ni­al Chair in Ener­gy Research
Uni­ver­si­ty of Mary­land, Col­lege Park, MD

Abstract:  Mem­brane reac­tor tech­nol­o­gy holds the promise to cir­cum­vent ther­mo­dy­nam­ic equi­lib­ri­um lim­i­ta­tions by in-situ removal of prod­uct species, result­ing in improved chem­i­cal yields.  Recent advances in mixed-con­duct­ing oxide-mem­brane tech­nol­o­gy present the pos­si­bil­i­ty for a dra­mat­ic reduc­tion in the cost of con­vert­ing petro­le­um, coal and bio­mass derived feed stocks to hydro­gen and oth­er “val­ue added” hydro­car­bons.  We have devel­oped nov­el mem­brane reac­tor tech­nol­o­gy, based on high tem­per­a­ture pro­ton con­duc­tors, that can con­vert a wide range of hydro­car­bons to pure H2, and syn­gas for syn­the­sis of liq­uid fuels and chem­i­cal feed stocks. By simul­ta­ne­ous H2 per­me­ation and catal­y­sis, we have demon­strat­ed the abil­i­ty to increase water gas shift yields >70% over ther­mo­dy­nam­ic lim­i­ta­tions. Sim­i­lar­ly, we have demon­strat­ed increas­es in steam reform­ing yields, and the abil­i­ty to reform CH4 with CO2.

More recent­ly we have devel­oped sin­gle-step gas to liq­uid reac­tors that con­vert nat­ur­al gas to C2+ prod­ucts with high yields and no unwant­ed oxi­da­tion byprod­ucts. The direct uti­liza­tion of CH4 and CO2 to simul­ta­ne­ous­ly pro­duce C2+ hydro­car­bons (C2 and aro­mat­ics) and syn­gas (CO and H2) on oppo­site sides of a mixed pro­ton­ic-elec­tron­ic con­duct­ing SrCe0.7Zr0.2Eu0.1O3-δ mem­brane reac­tor is demon­strat­ed. On one side (inte­ri­or) of the mem­brane reac­tor, direct non-oxida­tive methane con­ver­sion (DNMC) over an iron/silica cat­a­lyst pro­duces C2+ hydro­car­bons and H2. On the oth­er side (out­er sur­face) of the mem­brane, per­me­at­ed H2 (dri­ving the DNMC reac­tion) reacts with a CO2 sweep gas to form CO and water via the reverse water gas shift (RWGS) reac­tion. This nov­el sin­gle H2-per­me­able mem­brane reac­tor simul­ta­ne­ous­ly address­es both reduc­tion of green­house gas (CO2 and CH4) emis­sions as well as pro­duc­tion of val­ue-added hydro­car­bon prod­ucts (C2+, CO, and H2) with in situ gas sep­a­ra­tion.  

Zeolite Encapsulated Metal Nanoparticles for Selective Tandem Catalysis

Feb­ru­ary 2019

Bingjun Xu, Uni­ver­si­ty of Delaware

Abstract: Het­ero­ge­neous catal­y­sis is one of the pil­lars of the ener­gy and
chem­i­cal indus­tries, and a cen­tral sci­ence in dri­ving the
accel­er­at­ing tran­si­tion to a car­bon neu­tral future.
Under­stand­ing cat­alyt­ic process­es medi­at­ed by sol­id sur­faces
on the mol­e­c­u­lar lev­el holds the key to cat­a­lyst design, but is
chal­leng­ing due to the com­plex­i­ty of the local envi­ron­ment in
which chem­i­cal trans­for­ma­tions occur. In this lec­ture,
encap­su­la­tion of met­al nanopar­ti­cles in zeo­lite crys­tals as an
effec­tive cat­a­lyst archi­tec­ture to medi­ate selec­tive tan­dem
upgrad­ing of bio­mass derived feed­stocks is dis­cussed in the
con­text of two case stud­ies. The sequence to which sub­strates
are exposed to dif­fer­ent active sites and the dis­tri­b­u­tion of
met­al and acid sites in zeo­lite crys­tals are shown to play deci­sive roles in deter­min­ing selec­tiv­i­ty
and sta­bil­i­ty of cat­a­lysts.

Theodore A. Koch Travel Award 2018–2019

Dear Col­leagues,

The Catal­y­sis Club of Philadel­phia (CCP) is tak­ing appli­ca­tions for the Theodore A. Koch Trav­el Award. 

The award is spon­sored in mem­o­ry of T.A Koch in order to rec­og­nize and reward grad­u­ate stu­dent achieve­ments in catal­y­sis research. T.A. Koch (1925–2014) was a chemist who worked at DuPont, and spent his entire career devel­op­ing chem­i­cal process­es and bring­ing them from the bench­top to com­mer­cial­iza­tion with marked cre­ativ­i­ty and tenac­i­ty. The award will pro­vide finan­cial sup­port to a grad­u­ate stu­dent up to the amount of $1000 to attend a con­fer­ence of his or her choice. The amount can be used to cov­er reg­is­tra­tion fees and/or trav­el expens­es.

Eli­gi­bil­i­ty: Grad­u­ate stu­dents that are mem­bers of the CCP and have paid the annu­al dues ($10).  Selec­tion will be based on poten­tial impact of the trav­el award to the student’s career goals, finan­cial need and over­all mer­it. (The com­plet­ed appli­ca­tion form should not exceed three pages.)

The appli­ca­tion form is due Feb­ru­ary 11th 2019, and the win­ner will be announced at our Feb­ru­ary 21st meet­ing.

Please send your appli­ca­tions to Eric Sacia (CCP Chair, eric.​r.​sacia@​dupont.​com).


Best Regards,

Eric Sacia

2018–2019 CCP Chair

Engineering Industrial Catalysts: A Personal Journey

Jan­u­ary 2019
Dr. Car­mo Pereira
DuPont Clean Tech­nolo­gies

Abstract: Indus­tri­al reac­tors enable chem­i­cal trans­for­ma­tions that may upgrade the qual­i­ty of the feed, pro­duce chem­i­cals, and/or reduce process pol­lu­tants. The cat­a­lysts in these reac­tors are engi­neered to obtain the required (steady state) through­put of prod­uct over a cer­tain time. In addi­tion to through­put, there are addi­tion­al com­mer­cial­iza­tion con­straints that involve cost, uptime, emis­sions, and project tim­ing. The prop­er design of the cat­a­lyst and reac­tor often is key to the suc­cess­ful deploy­ment of the process.
In addi­tion to iden­ti­fy­ing the active site and the reac­tion mech­a­nism, addi­tion­al appli­ca­tion devel­op­ment work is required to com­mer­cial­ize a cat­a­lyst. The active site must func­tion with­in a range of oper­at­ing con­di­tions and in the pres­ence of impu­ri­ties that may impact activ­i­ty and selec­tiv­i­ty. Reac­tor pres­sure drop con­straints can dic­tate the size and struc­ture of the cat­a­lyst. The avail­abil­i­ty of active sites in a pel­let is max­i­mized by opti­miz­ing its size, shape and pore struc­ture to min­i­mize heat and mass trans­port lim­i­ta­tions. The num­ber of active sites in a cat­a­lyst may dra­mat­i­cal­ly decrease with time due to poi­son­ing, mask­ing, sin­ter­ing, or pore block­age. An under­stand­ing of the deac­ti­va­tion mech­a­nism under oper­at­ing con­di­tions pro­vides a basis for the reac­tor oper­at­ing strat­e­gy and for siz­ing reac­tors that have a war­rant­ed life. A process flow­sheet con­tain­ing a use­ful reac­tor mod­el may be sub­se­quent­ly val­ue-engi­neered to cost-effec­tive­ly meet the pro­cess­ing objec­tive.
This talk will present sev­er­al vignettes from the author’s expe­ri­ence where chem­i­cal reac­tion engi­neer­ing method­olo­gies were used to engi­neer indus­tri­al cat­a­lysts used in petro­chem­i­cal, chem­i­cal, and envi­ron­men­tal appli­ca­tions.

Catalysis Club of Philadelphia’s Annual Student Poster Session – Award Winners

Despite some unfore­seen and unsafe weath­er con­di­tions that led to can­cel­la­tions, there was still quite an impres­sive turnout lead­ing to anoth­er suc­cess­ful CCP poster ses­sion this year! Some ~19 stu­dents/­post-docs braved the weath­er and pre­sent­ed. For those who were not able to attend due to weath­er, we hope to see you (and bet­ter weath­er) next year. Whether you could attend or not, thanks to every­one for your com­mit­ment to mak­ing this anoth­er fan­tas­tic year for CCP!
Five win­ners were cho­sen based on crowd vot­ing fol­lowed by indi­vid­ual judg­ing by CCP offi­cers. Each win­ner will receive a mon­e­tary reward and the over­all win­ner is invit­ed to give a talk at the annu­al CCP Sym­po­sium in Spring 2019.

2018 CCP Poster Ses­sion Win­ners
Natalia Rodriquez Quiroz
Chao Lin
Elvis Ebikade
Jen­nifer Lee
Yuan Cheng

Left-to-right: Eric Sacia (CCP Chair), Yuan Cheng, Natalia Rodriquez Quiroz, Jen­nifer Lee, Elvis Ebikade, and Chao Lin. Con­grat­u­la­tions to all the win­ners!

How can the modern scanning transmission electron microscope aid catalysis science?

Novem­ber 2018
Prof. Eric A. Stach
Uni­ver­si­ty of Penn­syl­va­nia
E-mail: stach@​seas.​upenn.​edu, Web:
Abstract: The past decade or so have seen a num­ber of tech­no­log­i­cal advances in the field of trans­mis­sion elec­tron microscopy that have dra­mat­i­cal­ly enhanced both the util­i­ty and uti­liza­tion of the instru­ment in the field of het­ero­ge­neous catal­y­sis. These include aber­ra­tion cor­rec­tion, enhanced detec­tors and improve­ments in sim­u­la­tion and analy­sis soft­ware. In this pre­sen­ta­tion, I will present sev­er­al spe­cif­ic exam­ples from both my own research and from oth­ers in the field to pro­vide a gen­er­al overview of the state of the art. In spe­cif­ic, I will describe the lim­its of spa­tial, spec­tro­scop­ic and tem­po­ral ener­gy res­o­lu­tion, and demon­strate how one can per­form both real time and operan­do mea­sure­ments do char­ac­ter­ize the inter­re­la­tion­ships between cat­a­lyst struc­ture and cat­a­lyst func­tion. Through the pre­sen­ta­tion, I will empha­size how these tech­niques are being imple­ment­ed at the Singh Cen­ter for Nan­otech­nol­o­gy at the Uni­ver­si­ty of Penn­syl­va­nia and how they are thus acces­si­ble to mem­bers of the Cat­a­lyst Club of Philadel­phia.

Ultra-Deep Diesel Hydrodesulfurization Catalysis and Process: A Tale of Two Sites

Octo­ber 2018 — F.G. Cia­pet­ta Award Lec­ture

Dr. Teh C. Ho
Hydro­car­bon Con­ver­sion Tech­nolo­gies
E-mail: , Web:
Abstract: Hydrodesul­fu­r­iza­tion cat­a­lysts have two types of active sites for hydro­gena­tion and hydrogenol­y­sis reac­tions. While hydro­gena­tion sites are more active for desul­fu­r­iz­ing refrac­to­ry sul­fur species, they are more vul­ner­a­ble to organon­i­tro­gen inhi­bi­tion than hydrogenol­y­sis sites. In con­trast, hydrogenol­y­sis sites are less active for desul­fu­r­iz­ing refrac­to­ry sul­fur species but are more resis­tant to organon­i­tro­gen inhi­bi­tion. This dichoto­my is exploit­ed to devel­op an ultra-deep hydrodesul­fu­r­iza­tion stacked-bed reac­tor com­pris­ing two cat­a­lysts of dif­fer­ent char­ac­ter­is­tics. The per­for­mance of this cat­a­lyst sys­tem can be supe­ri­or or infe­ri­or to that of either cat­a­lyst alone. A the­o­ry is devel­oped to pre­dict the opti­mum stack­ing con­fig­u­ra­tion for max­i­mum syn­er­gies between the two cat­a­lysts. The best con­fig­u­ra­tion pro­vides the pre­cise envi­ron­ment for the cat­a­lysts to reach their full poten­tials, result­ing in the small­est reac­tor vol­ume and max­i­mum ener­gy sav­ing. Mod­el pre­dic­tions are con­sis­tent with exper­i­men­tal results. A selec­tiv­i­ty-activ­i­ty dia­gram is devel­oped for guid­ing the devel­op­ment of stacked-bed cat­a­lyst sys­tems.