2010 Spring Symposium

 
Mark A. Sny­der
P.C. Rossin Assis­tant Pro­fes­sor
Depart­ment of Chem­i­cal Engi­neer­ing
Lehigh Uni­ver­si­ty
Beth­le­hem, PA 18015

Abstract — Despite the promise for deriv­ing liq­uid hydro­car­bon fuels and high-val­ue chem­i­cals from renew­able cel­lu­losic feed­stocks, var­i­ous tech­no­log­i­cal chal­lenges have sti­fled the rapid com­mer­cial­iza­tion of the inte­grat­ed biore­fin­ery. The effi­cient and selec­tive down­stream pro­cess­ing of cel­lu­lose deriv­a­tives (e.g., hex­ose, fruc­tose, glu­cose, etc.) exists as a for­mi­da­ble pro­cess­ing bot­tle­neck. Owing to prop­er­ties such as breadth of oper­at­ing con­di­tions, des­ignable chem­i­cal selec­tiv­i­ty, and recy­cla­bil­i­ty, het­ero­ge­neous cat­alyt­ic routes serve as an attrac­tive means, in lieu of bio­log­i­cal, ther­mo­chem­i­cal, and homo­ge­neous ones, for effi­cient hydrother­mal pro­cess­ing of sug­ary cel­lu­lose deriv­a­tives. Yet, hydrother­mal insta­bil­i­ty of cur­rent cat­alyt­ic sup­ports opens excit­ing oppor­tu­ni­ties for the devel­op­ment of next-gen­er­a­tion cat­a­lysts capa­ble of meet­ing selec­tiv­i­ty, effi­cien­cy, and sta­bil­i­ty needs of the future biore­fin­ery.

This talk will high­light efforts to real­ize hydrother­mal­ly sta­ble inor­gan­ic mate­ri­als bear­ing mul­ti­scale, three-dimen­sion­al­ly ordered pore topol­o­gy and tun­able sur­face func­tion­al­i­ty. Specif­i­cal­ly, it will focus on a hier­ar­chi­cal nan­otem­plat­ing approach in which pre-formed inor­gan­ic nanopar­ti­cles are assem­bled into ordered col­loidal crys­tal struc­tures and employed as hard, sac­ri­fi­cial tem­plates for both direct and indi­rect repli­ca for­ma­tion of var­i­ous hydrother­mal­ly sta­ble porous mate­ri­als (e.g., car­bon, tita­nia, zeo­lite). The work is pred­i­cat­ed upon the hypoth­e­sis that hard inor­gan­ic tem­plates help resist pore col­lapse dur­ing struc­tur­al coars­en­ing or con­fined growth of inor­gan­ic repli­ca mate­ri­als, and that decou­pling tem­plate for­ma­tion and repli­ca­tion allows for pre­cise and ver­sa­tile engi­neer­ing of the tem­plate, and thus the repli­ca pore topol­o­gy.

This talk will focus on var­i­ous stages of hier­ar­chi­cal mate­ri­als assem­bly, begin­ning with tech­niques for con­trolled syn­the­sis of pri­ma­ry inor­gan­ic nanopar­ti­cle build­ing units with nanome­ter res­o­lu­tion, and encom­pass­ing descrip­tions of their assem­bly into ordered porous struc­tures, tem­plat­ing of high­er-order porous mate­ri­als, and real­iza­tion of mul­ti­scale (e.g., micro-/me­so­porous) porous sub­strates. Exam­ples of mate­ri­als that will be dis­cussed include mono- and mul­ti-lay­er col­loidal crys­tal films, three-dimen­sion­al­ly ordered meso­porous (3DOm) car­bon and tita­nia repli­ca par­ti­cles and thin films, size-tun­able, uni­form­ly shaped zeolitic (i.e., sil­i­calilte-1) nanocrys­tals, and 3DOm-imprint­ed sin­gle crys­tal zeo­lite par­ti­cles. The result­ing tun­able porous mate­ri­als hold excit­ing impli­ca­tions for appli­ca­tions rang­ing from catal­y­sis to mol­e­c­u­lar sep­a­ra­tions, and simul­ta­ne­ous reac­tion-sep­a­ra­tions tech­nolo­gies.

Speaker’s Biog­ra­phy — Mark A. Sny­der obtained his B.S in Chem­i­cal Engi­neer­ing with high­est hon­ors from Lehigh Uni­ver­si­ty in 2000, and his Ph.D. in Chem­i­cal Engi­neer­ing from the Uni­ver­si­ty of Delaware in 2006. His doc­tor­al research on mul­ti­scale mod­el­ing of mol­e­c­u­lar trans­port in poly­crys­talline zeo­lite mem­branes was rec­og­nized with an Amer­i­can Insti­tute of Chem­i­cal Engi­neers (AIChE) Grad­u­ate Research Award in 2005. Dur­ing his doc­tor­al work, he was also award­ed the T.W. Fras­er and Shirley Rus­sell Teach­ing Fel­low­ship (2004), the Robert L. Pig­ford Teach­ing Assis­tant Award (2003), and the Robert L. Pig­ford Grad­u­ate Fel­low­ship (2000). Sny­der car­ried out post-doc­tor­al research in the Depart­ment of Chem­i­cal Engi­neer­ing and Mate­ri­als Sci­ence at the Uni­ver­si­ty of Min­neso­ta from 2006–2008, inves­ti­gat­ing the benign syn­the­sis of met­al oxide nanopar­ti­cles and their assem­bly into mono- to mul­ti-lay­er porous thin films, perms­e­lec­tive encap­su­la­tion of liv­ing cells towards nov­el ther­a­peu­tics, and for­ma­tion of repli­ca porous struc­tures. Sny­der joined Lehigh University’s Depart­ment of Chem­i­cal Engi­neer­ing in August 2008 as an Assis­tant Pro­fes­sor, and was award­ed a P.C. Rossin Assis­tant Pro­fes­sor­ship in June 2009, a posi­tion that he will hold through 2011. At Lehigh, Snyder’s Porous and Func­tion­al­ized Nano­ma­te­ri­als Lab focus­es on the ratio­nal design and engi­neer­ing of func­tion­al­ized inor­gan­ic nanopar­ti­cles and porous mate­ri­als pri­mar­i­ly for catal­y­sis, mem­brane-based sep­a­ra­tions, and inte­grat­ed reac­tion-sep­a­ra­tion tech­nolo­gies span­ning appli­ca­tions in bio­fu­els, renew­able chem­i­cals, dye-sen­si­tized solar cells, and car­bon cap­ture.