Down­load Poster Abstracts:

 
Per­va­sive­ness of Sur­face Met­al Oxide Phas­es In Mixed Oxide Cat­a­lysts
Israel E. Wachs
Lehigh Uni­ver­si­ty, Beth­le­hem, PA

Abstract — Mixed oxide cat­alyt­ic mate­ri­als pos­sess two or more met­al oxide com­po­nents as found in bulk mixed met­al oxides (sto­i­chio­met­ric oxides as well as sol­id solu­tions), poly­oxo meta­lates (POMs), mol­e­c­u­lar sieves, zeo­lites, clays, hydro­tal­cites and sup­port­ed met­al oxides. Although it is now well estab­lished that two-dimen­­sion­al sur­face met­al oxide phas­es are present for sup­port­ed met­al oxides on tra­di­tion­al sup­ports (e.g., Al2O3, TiO2, ZrO2, SiO2, etc.), it is not cur­rent­ly appre­ci­at­ed that such sur­face met­al oxide species or phas­es are also present for oth­er types of mixed oxides. For exam­ple, recent sur­face analy­ses have demon­strat­ed that sto­i­chio­met­ric bulk mixed met­al oxides also pos­sess sur­face met­al oxide phas­es that con­trol their cat­alyt­ic activ­i­ty. For exam­ple, the cat­alyt­ic active sites for methanol oxi­da­tion to formalde­hyde over the bulk Fe2(MoO4)3 mixed oxide cat­a­lyst are sur­face MoOx species and not the bulk Fe2(MoO4)3 phase as pre­vi­ous­ly thought in the catal­y­sis lit­er­a­ture. The nanome­ter sized clus­ters in POMs also pos­sess sur­face species when a sec­ond met­al oxide com­po­nent is intro­duced (e.g., H3+xPW12-xMxO40). Depo­si­tion of met­al oxides into mol­e­c­u­lar sieves, zeo­lites, clays and hydro­tal­cites also results in the met­al oxide addi­tive usu­al­ly being present as sur­face met­al oxide species that are the cat­alyt­ic active sites for many redox and acid reac­tions. The for­ma­tion of these sur­face met­al oxide phas­es is dri­ven by their low sur­face free ener­gy and low Tam­mann tem­per­a­ture for many met­al oxides of inter­est in catal­y­sis (e.g., VOx, MoOx, CrOx, ReOx, WOx, etc.).

TBA

Sup­ported Met­al Cat­a­lysts — Issues and Oppor­tu­ni­ties
Stu­art Soled, Exxon­Mo­bil

 
Oxida­tive Dehy­dro­gena­tion of Ethane to Eth­yl­ene
Anne M. Gaffney, AMG Catal­y­sis and Chem­istry Con­sult­ing, LLC
 

Down­load announce­ment

.