<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Taifan, William</style></author><author><style face="normal" font="default" size="100%">Bucko, Tomas</style></author><author><style face="normal" font="default" size="100%">Baltrusaitis, Jonas.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Catalytic conversion of ethanol to 1,3-butadiene on MgO: A comprehensive mechanism elucidation using DFT calculations.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Catalysis</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2017</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2016///</style></date></pub-dates></dates><publisher><style face="normal" font="default" size="100%">Elsevier Inc.</style></publisher><volume><style face="normal" font="default" size="100%">346</style></volume><pages><style face="normal" font="default" size="100%">78-91</style></pages><isbn><style face="normal" font="default" size="100%">0021-9517</style></isbn><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In this work, we performed periodic D. Functional Theory calcns. and explored reactive pathways of ethanol catalysis to catalytically form 1,3-butadiene on undoped MgO surface.  We have identified crit. reactive intermediates, as well as thermodn. and kinetic barriers involved in the overall reactive landscape.  The overall free energy surface was explored for the highly debated reaction mechanisms, including Toussaint's aldol condensation mechanism, Fripiat's Prins mechanism and mechanism based on Ostromislensky's hemiacetal rearrangement.  Thermodn. and kinetics data calcd. showed four rate limiting steps in the overall process.  In particular, ethanol dehydration to form ethylene possessed lower energy barrier than dehydrogenation to yield acetaldehyde suggesting competing reactive pathways.  C-C bond coupling to form acetaldol (3-hydroxybutanal) is preceded with 16 kcal/mol forward reaction barrier.  Direct reaction of ethylene and acetaldehyde proceeds with a free energy barrier of 29 kcal/mol suggesting that Prins condensation is an alternative route.  Finally, thermodn. stability of 1-ethoxyethanol prevents further reaction via hemiacetal rearrangement.  The results here provide a first glimpse into the overall 1,3-butadiene formation mechanism on undoped MgO reactive sites in light of the vast literature discussing variety of the proposed mechanistic pathways mostly based on conventional homogenous org. chem. reactions. [on SciFinder(R)]</style></abstract><notes><style face="normal" font="default" size="100%">CAPLUS AN 2016:2125552(Journal)</style></notes></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Taifan, William</style></author><author><style face="normal" font="default" size="100%">Baltrusaitis, Jonas.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">CH4 conversion to value added products: Potential, limitations and extensions of a single step heterogeneous catalysis.</style></title><secondary-title><style face="normal" font="default" size="100%">Applied Catalysis, B: Environmental</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">review methane conversion heterogeneous catalysis</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2016</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2016</style></date></pub-dates></dates><publisher><style face="normal" font="default" size="100%">Elsevier B.V.</style></publisher><volume><style face="normal" font="default" size="100%">198</style></volume><pages><style face="normal" font="default" size="100%">525 - 547</style></pages><isbn><style face="normal" font="default" size="100%">0926-3373</style></isbn><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">A review.  Natural gas is envisioned as a primary source of energy and hydrocarbons in the foreseeable future.  Though shale gas has recently become abundant, it has two main concerns: its environmental impact and sustainable utilization.  The former is the result of recent reports of natural gas emissions and flares into the environment, where it acts as a powerful greenhouse gas, whereas the latter is dictated by the need for efficient hydrocarbon utilization.  Modern natural gas processing units that yield clean fuels and feedstock from methane, CH4, require extremely large capital investments and are not economical in remote natural gas extn. sites.  Single step (direct), non-syngas based catalytic routes of CH4 conversion to value added products have not been competitive economically and need to be reevaluated in the light of shale gas availability.  This perspective discusses general considerations for the desired hydrocarbon products, the thermodn. limitations involved in a single step conversion of CH4 and heterogeneous catalytic routes based on high temps. and oxide based catalysts.  We then discuss other catalysts and methods of CH4 activation that have recently emerged and are conceptually different from metal oxide catalyst based routes, such as those using sulfur or halogens.  Lastly, we discuss a possible route of CH4 monetization beyond the first reactive product (such as ethylene oligomerization into fuels), as well as currently explored photo(electro)chem. routes of CH4 activation. [on SciFinder(R)]</style></abstract><notes><style face="normal" font="default" size="100%">CAPLUS AN 2016:1094228(Journal; General Review; Online Computer File)</style></notes></record></records></xml>