This work was supported by the Department of Energy Bioenergy Technologies Office under Contract no. DE-AC36-08-GO28308. The U.S. Government retains and the publisher, by accepting the article for publication, acknowledges that the U.S. Government retains a nonexclusive, paid up, irrevocable, worldwide license to publish or reproduce the published form of this work, or allow others to do so, for U.S. Government purposes.

<ol>
	<li>Cvetanovi&#263;, R. J., Amenomiya, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Application+of+a+Temperature-Programmed+Desorption+Technique+to+Catalyst+Studies.">Application of a Temperature-Programmed Desorption Technique to Catalyst Studies.</a> Adv. Catal. 17, 103-149 (1967).</li><li>Falconer, J. L., Schwarz, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Temperature-Programmed+Desorption+and+Reaction:+Applications+to+Supported+Catalysts.">Temperature-Programmed Desorption and Reaction: Applications to Supported Catalysts.</a> Catal. Rev. - Sci. Eng. 25 (2), 141-227 (1983).</li><li>Hurst, N. W., Gentry, S. J., Jones, A., McNicol, B. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Temperature+Programmed+Reduction.">Temperature Programmed Reduction.</a> Catal. Rev. - Sci. Eng. 24 (2), 233-309 (1982).</li><li>Sanchez, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=When+Gold+Is+Not+Noble:+Nanoscale+Gold+Catalysts.">When Gold Is Not Noble: Nanoscale Gold Catalysts.</a> J. Phys. Chem. A. 103 (48), 9573-9578 (1999).</li><li>Alayoglu, S., Nilekar, A. U., Mavrikakis, M., Eichhorn, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ru-Pt+core-shell+nanoparticles+for+preferential+oxidation+of+carbon+monoxide+in+hydrogen.">Ru-Pt core-shell nanoparticles for preferential oxidation of carbon monoxide in hydrogen.</a> Nat Mater. 7 (4), 333-338 (2008).</li><li>Wachs, I. E., Madix, R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+oxidation+of+methanol+on+a+silver+(110)+catalyst.">The oxidation of methanol on a silver (110) catalyst.</a> Surf. Sci. 76 (2), 531-558 (1978).</li><li>Topsoe, N. Y., Topsoe, H., Dumesic, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vanadia/Titania+Catalysts+for+Selective+Catalytic+Reduction+(SCR)+of+Nitric-Oxide+by+Ammonia.">Vanadia/Titania Catalysts for Selective Catalytic Reduction (SCR) of Nitric-Oxide by Ammonia.</a> J Catal. 151 (1), 226-240 (1995).</li><li>Clarke, D. B., Bell, A. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+Infrared+Study+of+Methanol+Synthesis+from+CO2+on+Clean+and+Potassium-Promoted+Cu/SiO2.">An Infrared Study of Methanol Synthesis from CO2 on Clean and Potassium-Promoted Cu/SiO2.</a> J Catal. 154 (2), 314-328 (1995).</li><li>Schaidle, J. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Experimental+and+Computational+Investigation+of+Acetic+Acid+Deoxygenation+over+Oxophilic+Molybdenum+Carbide:+Surface+Chemistry+and+Active+Site+Identity.">Experimental and Computational Investigation of Acetic Acid Deoxygenation over Oxophilic Molybdenum Carbide: Surface Chemistry and Active Site Identity.</a> ACS Catal. 6 (2), 1181-1197 (2016).</li><li>Ruddy, D. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recent+advances+in+heterogeneous+catalysts+for+bio-oil+upgrading+via+"ex+situ+catalytic+fast+pyrolysis":+catalyst+development+through+the+study+of+model+compounds.">Recent advances in heterogeneous catalysts for bio-oil upgrading via "ex situ catalytic fast pyrolysis": catalyst development through the study of model compounds.</a> Green Chem. 16 (2), 454-490 (2014).</li><li>Dutta, A., Schaidle, J. A., Humbird, D., Baddour, F. G., Sahir, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Conceptual+Process+Design+and+Techno-Economic+Assessment+of+Ex+Situ+Catalytic+Fast+Pyrolysis+of+Biomass:+A+Fixed+Bed+Reactor+Implementation+Scenario+for+Future+Feasibility.">Conceptual Process Design and Techno-Economic Assessment of Ex Situ Catalytic Fast Pyrolysis of Biomass: A Fixed Bed Reactor Implementation Scenario for Future Feasibility.</a> Top. Catal. 59 (1), 2-18 (2016).</li><li>Venkatakrishnan, V. K., Delgass, W. N., Ribeiro, F. H., Agrawal, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Oxygen+removal+from+intact+biomass+to+produce+liquid+fuel+range+hydrocarbons+via+fast-hydropyrolysis+and+vapor-phase+catalytic+hydrodeoxygenation.">Oxygen removal from intact biomass to produce liquid fuel range hydrocarbons via fast-hydropyrolysis and vapor-phase catalytic hydrodeoxygenation.</a> Green Chem. 17 (1), 178-183 (2015).</li><li>Bej, S. K., Thompson, L. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Acetone+condensation+over+molybdenum+nitride+and+carbide+catalysts.">Acetone condensation over molybdenum nitride and carbide catalysts.</a> Appl. Catal., A. 264 (2), 141-150 (2004).</li><li>Sullivan, M. M., Held, J. T., Bhan, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Structure+and+site+evolution+of+molybdenum+carbide+catalysts+upon+exposure+to+oxygen.">Structure and site evolution of molybdenum carbide catalysts upon exposure to oxygen.</a> J Catal. 326, 82-91 (2015).</li><li>Lee, W. S., Kumar, A., Wang, Z. S., Bhan, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chemical+Titration+and+Transient+Kinetic+Studies+of+Site+Requirements+in+Mo2C-Catalyzed+Vapor+Phase+Anisole+Hydrodeoxygenation.">Chemical Titration and Transient Kinetic Studies of Site Requirements in Mo2C-Catalyzed Vapor Phase Anisole Hydrodeoxygenation.</a> ACS Catal. 5 (7), 4104-4114 (2015).</li><li>Ren, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Selective+Hydrodeoxygenation+of+Biomass-Derived+Oxygenates+to+Unsaturated+Hydrocarbons+using+Molybdenum+Carbide+Catalysts.">Selective Hydrodeoxygenation of Biomass-Derived Oxygenates to Unsaturated Hydrocarbons using Molybdenum Carbide Catalysts.</a> Chemsuschem. 6 (5), 798-801 (2013).</li><li>Grob, R. L., Kaiser, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Modern Practice of Gas Chromatography. , 403-460 (2004).</li><li>Guiochon Georges, L., Guillemin Claude, <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Journal of Chromatography Library. 42, 563-586 (1988).</li><li>Guiochon Georges, L., Guillemin Claude, <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Journal of Chromatography Library. 42, 587-627 (1988).</li><li>Guiochon Georges, L., Guillemin Claude, <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Journal of Chromatography Library. 42, 629-659 (1988).</li><li>Guiochon Georges, L., Guillemin Claude, <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Journal of Chromatography Library. 42, 661-687 (1988).</li><li>Baddour, F. G., Nash, C. P., Schaidle, J. A., Ruddy, D. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthesis+of+&#945;-MoC1-x+Nanoparticles+with+a+Surface-Modified+SBA-15+Hard+Template:+Determination+of+Structure-Function+Relationships+in+Acetic+Acid+Deoxygenation.">Synthesis of &#945;-MoC1-x Nanoparticles with a Surface-Modified SBA-15 Hard Template: Determination of Structure-Function Relationships in Acetic Acid Deoxygenation.</a> Angew. Chem., Int. Ed. n/a-n/a. , (2016).</li><li>Habas, S. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Facile+Molecular+Precursor+Route+to+Metal+Phosphide+Nanoparticles+and+Their+Evaluation+as+Hydrodeoxygenation+Catalysts.">A Facile Molecular Precursor Route to Metal Phosphide Nanoparticles and Their Evaluation as Hydrodeoxygenation Catalysts.</a> Chem. Mater. 27 (22), 7580-7592 (2015).</li><li>Zhang, Q., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Deconvolution+and+quantification+of+hydrocarbon-like+and+oxygenated+organic+aerosols+based+on+aerosol+mass+spectrometry.">Deconvolution and quantification of hydrocarbon-like and oxygenated organic aerosols based on aerosol mass spectrometry.</a> Environ Sci Technol. 39 (13), 4938-4952 (2005).</li><li>Ko, E. I., Benziger, J. B., Madix, R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reactions+of+Methanol+on+W(100)+and+W(100)-(5+X+1)C+Surfaces.">Reactions of Methanol on W(100) and W(100)-(5 X 1)C Surfaces.</a> J Catal. 62 (2), 264-274 (1980).</li><li>Pestman, R., Koster, R. M., Pieterse, J. A. Z., Ponec, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reactions+of+carboxylic+acids+on+oxides:+1.+Selective+hydrogenation+of+acetic+acid+to+acetaldehyde.">Reactions of carboxylic acids on oxides: 1. Selective hydrogenation of acetic acid to acetaldehyde.</a> J Catal. 168 (2), 255-264 (1997).</li><li>Pestman, R., Koster, R. M., Van Duijne, A., Pieterse, J. A. Z., Ponec, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reactions+of+carboxylic+acids+on+oxides:+2.+Bimolecular+reaction+of+aliphatic+acids+to+ketones.">Reactions of carboxylic acids on oxides: 2. Bimolecular reaction of aliphatic acids to ketones.</a> J Catal. 168 (2), 265-272 (1997).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=NIST+Standard+Reference+Database+Number+69.">NIST Standard Reference Database Number 69.</a> NIST Chemistry WebBook. , (2016).</li><li>Ausloos, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+critical+evaluation+of+a+comprehensive+mass+spectral+library.">The critical evaluation of a comprehensive mass spectral library.</a> J. Am. Soc. Mass Spectrom. 10 (4), 287-299 (1999).</li><li>Barwick, V., Langley, J., Mallet, T., Stein, B., Webb, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Best Practice Guide for Generating Mass Spectra. , (2006).</li><li>Lecchi, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Method+for+Monitoring+and+Controlling+Reproducibility+of+Intensity+Data+in+Complex+Electrospray+Mass+Spectra:+A+Thermometer+Ion-based+Strategy.">A Method for Monitoring and Controlling Reproducibility of Intensity Data in Complex Electrospray Mass Spectra: A Thermometer Ion-based Strategy.</a> J. Am. Soc. Mass Spectrom. 20 (3), 398-410 (2009).</li></ol>

The authors have nothing to disclose.

O método TPRxn é uma ferramenta poderosa para a triagem de materiais catalíticos, fornecer informações sobre a actividade e selectividade de um catalisador como uma função da temperatura de reacção. Outros métodos programada de temperatura, tais como TPD, TPO e TPR pode fornecer informações sobre a força de adsorção dos reagentes, o número de sítios de adsorção, e catalisador procedimentos pré-tratamento adequado, mas não fornecem dados de desempenho catalíticos diretos. É importante notar que o m...

Temperatura de reacção programada (TPRxn) é um dos muitos métodos de temperatura programada, incluindo a dessorção (TPD), oxidação (TPO), e redução (TPR), e prossegue através da exposição de um catalisador para um concorrente reagente com ou seguido por um aumento constante temperatura. 1, 2, 3 TPRxn é uma técnica transiente que fornece informação sobre a actividade do catalisador e selectividade em função da temperatura de reacção. 4, 5, 6 Também é uma técnica popular: a busca das palavras-chave &quot;temperatura programada reação nos rendimentos literatura mais de 1.000 fontes citando seu uso. TPRxn experiências são tipicamente realizadas num sistema de micro reactor, equipado com um espectrómetro de massa (MS) para análise em tempo real do efluente do reactor e correlação de performance com a temperatura. gases reagentes pode ser introduzido utilizando controladores de fluxo de massa e os líquidos podem ser introduzidos por meio de uma bomba de seringa ou de vapores, fazendo borbulhar um gás inerte através de um líquido. O catalisador é muitas vezes pré-tratado in situ para formar a fase catalítica desejada para a reacção. Alguns sistemas são equipados com equipamento de análise adicional, além do espectrômetro de massa típica, para fornecer informação quantitativa ou qualitativa sobre a seletividade do catalisador, de superfície espécies presentes no catalisador, ou mecanismo de reação. Por exemplo, a temperatura programada em Fourier Transform situ Espectroscopia no Infravermelho (FTIR) fornece informações sobre a evolução das espécies de superfície com diferentes temperaturas da reacção. 7, 8 O sistema TPRxn demonstrado neste trabalho está equipado com um cromatograma de gás (GC), para além dos de MS mais típicos. Este GC, equipado com quatro colunas paralelas, permite a quantificação mais precisaficação dos produtos da reacção, mas é limitada na frequência análise por o tempo que leva os produtos para eluir através das colunas. Assim, a combinação de EM e CG pode ser particularmente útil para o acoplamento de identificação em tempo real com a quantificação precisa dos reagentes e produtos. Aqui, nós aplicamos a metodologia TPRxn para estudar a desoxigenação de ácido acético sobre catalisadores de carboneto de molibdénio. Esta é uma reacção interessante e importante na investigação do catalisador, como o ácido acético é um análogo útil para os diversos ácidos carboxílicos presentes nos vapores de biomassa de pirólise. 9 O alto teor de oxigênio nos vapores de pirólise de biomassa exige a remoção de oxigênio para produzir combustíveis de hidrocarbonetos, 10, 11, 12 e catalisadores de carboneto de molibdénio têm mostrado promissor desempenho desoxigenação para muitos compostos modelo vapor biomassa de pirólise, incluindo furfural, 1-propanol,compostos fenólicos e ácido acético. 9, 13, 14, 15, 16 No entanto, a actividade e selectividade dos catalisadores de carboneto de molibdénio em reacções de desoxigenação é dependente da estrutura do catalisador e da composição, as espécies reagentes e as condições de reacção. Os dados recolhidos a partir TPRxn de ácido acético mostra que os catalisadores de carboneto de molibdénio são ativos para reações de desoxigenação acima ca. 300 ° C, e quando combinado com a informação de classificação do catalisador permite a quantificação da actividade do catalisador em função da temperatura através do cálculo das taxas de turnover do ácido acético. Os resultados mostram que TPRxn desoxigenação (isto é, CO bond-quebra) produtos são favorecidos em temperaturas abaixo de ca. 400 ° C e descarbonilaï¿½o (ou seja, CC vínculo de quebra) produtos são favovermelho a temperaturas acima de ca. 400 ° C. Além disso, estudos TPRxn ilustrar as mudanças na actividade e selectividade dos catalisadores de carboneto de molibdénio produzidos usando vários processos de síntese (isto é, a produção de diferentes estruturas de catalisador de carboneto de molibdénio e composições). Ainda assim, o valor desta informação e, de modo mais geral, a aplicação bem sucedida de dados experimentais para o projecto TPRxn catalisador e optimização de processos é uma função da qualidade dos dados obtidos. cuidadosa consideração e conhecimento das dificuldades potenciais e limitações destacadas durante todo o procedimento TPRxn é primordial.

<table border="0" cellpadding="0" cellspacing="0" width="942">
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	<tbody>
		<tr height="57">
			<td height="57" style="height:58px;width:215px;">glacial acetic acid</td>
			<td style="width:179px;">Cole-Parmer</td>
			<td style="width:148px;">EW-88401-62</td>
			<td style="width:401px;">alternate supplier acceptable if ACS purity grade. See caution statement in protocol for safety information</td>
		</tr>
		<tr height="57">
			<td height="57" style="height:58px;width:215px;">UHP H&#8322;</td>
			<td style="width:179px;">Airgas</td>
			<td style="width:148px;">HY R300</td>
			<td>alternate supplier acceptable if &#62;99.99% purity</td>
		</tr>
		<tr height="57">
			<td height="57" style="height:58px;width:215px;">UHP He</td>
			<td style="width:179px;">Airgas</td>
			<td style="width:148px;">HE R300SS</td>
			<td>alternate supplier acceptable if &#62;99.99% purity</td>
		</tr>
		<tr height="57">
			<td height="57" style="height:58px;width:215px;">UHP Ar</td>
			<td style="width:179px;">Arigas</td>
			<td style="width:148px;">AR R200</td>
			<td>alternate supplier acceptable if &#62;99.99% purity</td>
		</tr>
		<tr height="57">
			<td height="57" style="height:58px;width:215px;">acetone</td>
			<td style="width:179px;">VWR International</td>
			<td style="width:148px;">BDH1101-4LP</td>
			<td>alternate supplier acceptable if &#62;99.5% purity</td>
		</tr>
		<tr height="57">
			<td height="57" style="height:58px;width:215px;">quartz chips</td>
			<td style="width:179px;">Powder Technology Inc.</td>
			<td style="width:148px;">Crushed Quartz</td>
			<td style="width:401px;">sieved 180-300 &#181;m, calcined in air at 500 &#176;C overnight</td>
		</tr>
		<tr height="56">
			<td height="56" style="height:56px;width:215px;">mass spectrometer - turbo vacuum pump</td>
			<td style="width:179px;">Pfeiffer Vacuum</td>
			<td style="width:148px;">TSU 071</td>
			<td style="width:401px;">mass spectrometer is controlled with LabVIEW 2010 software package (National Instruments)</td>
		</tr>
		<tr height="56">
			<td height="56" style="height:56px;width:215px;">mass spectrometer - turbo vacuum pump</td>
			<td style="width:179px;">Stanford Research Systems</td>
			<td style="width:148px;">RGA100</td>
			<td style="width:401px;"></td>
		</tr>
		<tr height="126">
			<td height="126" style="height:126px;width:215px;">micro gas chromatograph</td>
			<td style="width:179px;">Agilent</td>
			<td style="width:148px;">CP740388</td>
			<td style="width:401px;">490 Micro GC; 4-channel system 
			Channel 1: 494001360 Molseive 10m, heated backflush 
			Channel 2: 494001460 PPU 10m, heated backflush 
			Channel 3: 490040 AL2O3/KCL 10+0.2m, heated backflush SPECIAL 
			Channel 4: 492005750 5CB 15m, heated</td>
		</tr>
		<tr height="56">
			<td height="56" style="height:56px;width:215px;">GC software</td>
			<td style="width:179px;">Aglient</td>
			<td style="width:148px;">OpenLAB CDS EZChrom Edition</td>
			<td style="width:401px;"></td>
		</tr>
		<tr height="57">
			<td height="57" style="height:58px;width:215px;">clean gas filters</td>
			<td style="width:179px;">Agilent</td>
			<td style="width:148px;">CP17974</td>
			<td>for use on GC carrier gases (He, Ar)</td>
		</tr>
		<tr height="57">
			<td height="57" style="height:58px;width:215px;">quartz &#34;U-tube&#34; reactor</td>
			<td style="width:179px;">n/a</td>
			<td style="width:148px;"></td>
			<td>hand blown glass, custom built to order</td>
		</tr>
		<tr height="57">
			<td height="57" style="height:58px;width:215px;">bubbler</td>
			<td style="width:179px;">n/a</td>
			<td style="width:148px;"></td>
			<td>custom built to order</td>
		</tr>
		<tr height="57">
			<td height="57" style="height:58px;width:215px;">ceramic furnace</td>
			<td style="width:179px;">Watlow</td>
			<td style="width:148px;">discontinued</td>
			<td>Similar furnace part #: VC401J12A-B000R</td>
		</tr>
		<tr height="57">
			<td height="57" style="height:58px;width:215px;">heat tape controller</td>
			<td style="width:179px;">n/a</td>
			<td style="width:148px;"></td>
			<td>custom built with Watlow EZ-zone parts</td>
		</tr>
		<tr height="57">
			<td height="57" style="height:58px;width:215px;">heat tape</td>
			<td style="width:179px;">Omega</td>
			<td style="width:148px;">FGH051-060</td>
			<td style="width:401px;">alternate supplier for extreme temperature heat tape acceptable</td>
		</tr>
		<tr height="57">
			<td height="57" style="height:58px;width:215px;">heat tape insulation</td>
			<td style="width:179px;">JEGS</td>
			<td style="width:148px;">710-80809</td>
			<td>alternate supplier acceptable</td>
		</tr>
		<tr height="57">
			<td height="57" style="height:58px;width:215px;">thermocouple</td>
			<td style="width:179px;">Omega</td>
			<td style="width:148px;">e.g., KMQSS-062U-18</td>
			<td>K-type thermocouples; alternate sizes may be required</td>
		</tr>
		<tr height="57">
			<td height="57" style="height:58px;width:215px;">thermocouple o-ring</td>
			<td style="width:179px;">Swagelok</td>
			<td style="width:148px;">VT-7-OR-001-1/2</td>
			<td>perfluoroelastomer(fluorocarbon FKM) o-ring</td>
		</tr>
		<tr height="57">
			<td height="57" style="height:58px;width:215px;">2 &#181;m solids filter, VCR gasket</td>
			<td style="width:179px;">Swagelok</td>
			<td style="width:148px;">SS-4-VCR-2-2M</td>
			<td></td>
		</tr>
		<tr height="57">
			<td height="57" style="height:58px;width:215px;">1 &#181;m orifice, VCR gasket</td>
			<td style="width:179px;">Lenox Laser</td>
			<td style="width:148px;">SS-4-VCR-2</td>
			<td>for mass spectrometer orifice</td>
		</tr>
		<tr height="93">
			<td height="93" style="height:94px;width:215px;">316/316L stainless steel tubing and fittings</td>
			<td style="width:179px;">Swagelok</td>
			<td style="width:148px;">Varies</td>
			<td style="width:401px;">See Swagelok &#39;VCR Metal Gasket Face Seal Fittings&#39; and &#39;Stainless Steel Seamless Tubing and Tube Support Systems&#39; catalogs for more information</td>
		</tr>
		<tr height="93">
			<td height="93" style="height:94px;width:215px;">316/316L stainless steel tubing and fittings</td>
			<td style="width:179px;">Swagelok</td>
			<td style="width:148px;">Varies</td>
			<td style="width:401px;">See Swagelok &#39;Integral-Bonnet Needle Valves&#39;, &#39;Bellows-Sealed Valves&#39; and &#39;One-Piece Instrumentation Ball Valves&#39; catalogs for more information</td>
		</tr>
	</tbody>
</table>

temperature-programmed deoxygenation of acetic acid on molybdenum carbide catalysts

Temperatura de reacção programada (TPRxn) é uma ferramenta simples e poderosa para o rastreio de desempenho do catalisador sólido a uma variedade de condições. Um sistema TPRxn inclui um reator, forno, gás e vapor de fontes, controle de fluxo, instrumentação para quantificar produtos de reacção (por exemplo, cromatógrafo a gás), e instrumentação para monitorar a reação em tempo real (por exemplo, espectrômetro de massa). Aqui, nós aplicamos a metodologia TPRxn para estudar catalisadores de carboneto de molibdênio para a desoxigenação de ácido acético, uma reação importante entre muitos na modernização / estabilização de vapores biomassa de pirólise. TPRxn é utilizado para avaliar a actividade do catalisador e selectividade e para testar vias de reacção (por exemplo, hipotéticas, descarbonilação, ketonization, e a hidrogenação). Os resultados do estudo de desoxigenação TPRxn ácido acético mostram que o carboneto de molibdénio é um catalisador activo para esta reacção a temperaturas acima de ca. 300 ° C e que os favores de reaçãodesoxigenação (isto é, CO bond-quebra) produtos em temperaturas abaixo de ca. 400 ° C e descarbonilaï¿½o (ou seja, CC vínculo de quebra) produtos em temperaturas acima de ca. 400 ° C.

A linha MS fornece a capacidade de analisar a composição do gás à saída do reactor, em tempo real. O MS on-line não é acoplado com qualquer dispositivo para separar os produtos antes da análise e, portanto, a identificação das espécies é um desafio para diferenciar entre os compostos com sobreposição de padrões de fragmentação de massa. Como mostrado na Tabela 2, muitos dos produtos comuns de ácido acético a partir de experiências TPRxn são caracteri...

Watch this Scientific Journal Video about Temperature-programmed Deoxygenation of Acetic Acid on Molybdenum Carbide Catalysts at JoVE.com

Temperature-programmed Deoxygenation of Acetic Acid on Molybdenum Carbide Catalysts

Apresentado aqui é um protocolo para a operação de um reactor à temperatura programada micro-escala para avaliar o desempenho catalítico de carboneto de molibdênio durante a desoxigenação ácido acético.

Desoxigenação à temperatura programada do ácido acético na Molibdênio Carbide Catalysts

Temperature programmed reaction (TPRxn) is a simple yet powerful tool for screening solid catalyst performance at a variety of conditions. A TPRxn system ...

temperature-programmed-deoxygenation-acetic-acid-on-molybdenum

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11.4K visualizações.  National Renewable Energy Laboratory.  Apresentado aqui é um protocolo para a operação de um reactor à temperatura programada micro-escala para avaliar o desempenho catalítico de carboneto de molibdênio durante a desoxigenação ácido acético. 

Vídeo: Temperature-programmed Deoxygenation of Acetic Acid on Molybdenum Carbide Catalysts

Preparation of Silica Nanoparticles Through Microwave-assisted Acid-catalysis

Microwave-assisted synthetic techniques were used to quickly and reproducibly produce silica nanoparticle sols using an acid catalyst with nanoparticle diameters ranging from 30-250 nm by varying the reaction conditions. Through the selection of a microwave compatible solvent, silicic acid precursor, catalyst, and microwave irradiation time, these microwave-assisted methods were capable of overcoming the previously reported shortcomings associated with synthesis of silica nanoparticles using microwave reactors. The siloxane precursor was hydrolyzed using the acid catalyst, HCl. Acetone, a low-tan &#948; solvent, mediates the condensation reactions and has minimal interaction with the electromagnetic field. Condensation reactions begin when the silicic acid precursor couples with the microwave radiation, leading to silica nanoparticle sol formation. The silica nanoparticles were characterized by dynamic light scattering data and scanning electron microscopy, which show the materials&#39; morphology and size to be dependent on the reaction conditions. Microwave-assisted reactions produce silica nanoparticles with roughened textured surfaces that are atypical for silica sols produced by St&#246;ber&#39;s methods, which have smooth surfaces.

Silica nanoparticles were prepared using acid-catalysis of a siloxane precursor and microwave-assisted synthetic techniques resulting in the controlled growth of nanomaterials ranging from 30-250 nm in diameter. The growth dynamics can be controlled by varying the initial silicic acid concentration, time of the reaction, and temperature of reaction.

Microwave-assisted synthetic techniques were used to quickly and reproducibly produce silica nanoparticle sols using an acid catalyst with nanoparticle ...

Química

Manufacturing of Three-dimensionally Microstructured Nanocomposites through Microfluidic Infiltration

Microstructured composite beams reinforced with complex three-dimensionally (3D) patterned nanocomposite microfilaments are fabricated via nanocomposite in&#64257;ltration of 3D interconnected microfluidic networks. The manufacturing of the reinforced beams begins with the fabrication of microfluidic networks, which involves layer-by-layer deposition of fugitive ink filaments using a dispensing robot, filling the empty space between filaments using a low viscosity resin, curing the resin and finally removing the ink.&#160;Self-supported 3D structures with other geometries and many layers (e.g.&#160;a few hundreds layers) could be built using this method. The resulting tubular micro&#64258;uidic networks are then infiltrated with thermosetting nanocomposite suspensions containing nanofillers (e.g.&#160;single-walled carbon nanotubes), and subsequently cured. The infiltration is done by applying a pressure gradient between two ends of the empty network (either by applying a vacuum or vacuum-assisted microinjection). Prior to the infiltration, the nanocomposite suspensions are prepared by dispersing nanofillers into polymer matrices using ultrasonication and three-roll mixing methods. The nanocomposites (i.e.&#160;materials infiltrated) are then solidified under UV exposure/heat cure, resulting in a 3D-reinforced composite structure. The technique presented here enables the design of functional nanocomposite macroscopic products for microengineering applications such as actuators and sensors.

Three-dimensional (3D) microstructured composite beams are fabricated through the directed and localized infiltration of nanocomposites into 3D porous microfluidic networks. The flexibility of this manufacturing method enables the utilization of different thermosetting materials and nanofillers in order to achieve a variety of functional 3D reinforced nanocomposite macroscopic products.

Fabricação de tridimensionalmente microestruturadas nanocompósitos através Microfluidic Infiltração

Microstructured composite beams reinforced with complex three-dimensionally (3D) patterned nanocomposite microfilaments are fabricated via nanocomposite ...

Reverse Microemulsion-mediated Synthesis of Monometallic and Bimetallic Early Transition Metal Carbide and Nitride Nanoparticles

A reverse microemulsion is used to encapsulate monometallic or bimetallic early transition metal oxide nanoparticles in microporous silica shells. The silica-encapsulated metal oxide nanoparticles are then carburized in a methane/hydrogen atmosphere at temperatures over 800 &#176;C to form silica-encapsulated early transition metal carbide nanoparticles. During the carburization process, the silica shells prevent the sintering of adjacent carbide nanoparticles while also preventing the deposition of excess surface carbon. Alternatively, the silica-encapsulated metal oxide nanoparticles can be nitridized in an ammonia atmosphere at temperatures over 800 &#176;C to form silica-encapsulated early transition metal nitride nanoparticles. By adjusting the reverse microemulsion parameters, the thickness of the silica shells, and the carburization/nitridation conditions, the transition metal carbide or nitride nanoparticles can be tuned to various sizes, compositions, and crystal phases. After carburization or nitridation, the silica shells are then removed using either a room-temperature aqueous ammonium bifluoride solution or a 0.1 to 0.5 M NaOH solution at 40-60 &#176;C. While the silica shells are dissolving, a high surface area support, such as carbon black, can be added to these solutions to obtain supported early transition metal carbide or nitride nanoparticles. If no high surface area support is added, then the nanoparticles can be stored as a nanodispersion or centrifuged to obtain a nanopowder.

A &#8220;removable ceramic coating method&#8221; is presented in visual format for the synthesis of non-sintered and metal-terminated monometallic and bimetallic early transition metal carbide and nitride nanoparticles with tunable sizes and crystal structures.

Inversa Síntese mediada por Microemulsão de monometálicos e bimetálico precoce de Metais de Transição Carbide e nitreto Nanopartículas

A reverse microemulsion is used to encapsulate monometallic or bimetallic early transition metal oxide nanoparticles in microporous silica shells. The ...

Dynamic Electrochemical Measurement of Chloride Ions

This protocol describes the dynamic measurement of chloride ions using the transition time of a silver silver chloride (Ag/AgCl) electrode. Silver silver chloride electrode is used extensively for potentiometric measurement of chloride ions concentration in electrolyte. In this measurement, long-term and continuous monitoring is limited due to the inherent drift and the requirement of a stable reference electrode. We utilized the chronopotentiometric approach to minimize drift and avoid the use of a conventional reference electrode. A galvanostatic pulse is applied to an Ag/AgCl electrode which initiates a faradic reaction depleting the Cl&#713; ions near the electrode surface. The transition time, which is the time to completely deplete the ions near the electrode surface, is a function of the ion concentration, given by the Nernst equation. The square root of the transition time is in linear relation to the chloride ion concentration. Drift of the response over two weeks is negligible (59 &#181;M/day) when measuring 1 mM [Cl&#713;]using a current pulse of 10 Am-2. This is a dynamic measurement where the moment of transition time determines the response and thus is independent of the absolute potential. Any metal wire can be used as a pseudo-reference electrode, making this approach feasible for long-term measurement inside concrete structures.

Dynamic measurement of chloride ions is presented. Transition time of an Ag/AgCl electrode, during a chronopotentiometric technique, can give the concentration of chloride ions in electrolyte. This method does not require a stable conventional reference electrode.

Dinâmica eletroquímico Medição de íons cloreto

This protocol describes the dynamic measurement of chloride ions using the transition time of a silver silver chloride (Ag/AgCl) electrode. Silver silver ...

Extraction and Purification of Polyphenols from Freeze-dried Berry Powder for the Treatment of Vascular Smooth Muscle Cells In Vitro

Epidemiological studies indicate that increased flavonoid intake correlates with decreased mortality due to cardiovascular diseases (CVD) in the United States (US) and Europe. Berries are widely consumed in the US and have a high polyphenolic content. Polyphenols have been shown to interact with many molecular targets and to exert numerous positive biological functions, including antioxidant, anti-inflammatory, and cardioprotective effects. Polyphenols isolated from blackberry (BL), raspberry (RB), and black raspberry (BRB) reduce oxidative stress and cellular senescence in response to angiotensin II (Ang II). This work provides a detailed description of the protocol used to prepare the polyphenol extracts from freeze-dried berries. Polyphenol extractions from freeze-dried berry powder were performed using 80% aqueous ethanol and an ultrasonic-assisted extraction method. The crude extract was further purified and fractionated using chloroform and ethyl acetate, respectively. The effects of both crude and purified extracts were tested on Vascular Smooth Muscle Cells (VSMCs) in culture.

Extraction and Purification of Polyphenols from Freeze-dried Berry Powder for the Treatment of Vascular Smooth Muscle Cells In Vitro

This work details a step-by-step method to prepare polyphenol-rich extracts from freeze-dried berry powder. In addition, it provides a thorough description of how to use these polyphenol-rich extracts in cell culture in the presence of the peptide hormone angiotensin II (Ang II) using Vascular Smooth Muscle Cells (VSMCs).

Extração e purificação de polifenóis a partir de pó de baga liofilizado para o tratamento de células musculares lisas vasculares<em&gt; In Vitro</em

Epidemiological studies indicate that increased flavonoid intake correlates with decreased mortality due to cardiovascular diseases (CVD) in the United ...

Synthesis and Testing of Supported Pt-Cu Solid Solution Nanoparticle Catalysts for Propane Dehydrogenation

A convenient method for the synthesis of bimetallic Pt-Cu catalysts and performance tests for propane dehydrogenation and characterization are demonstrated here. The catalyst forms a substitutional solid solution structure, with a small and uniform particle size around 2 nm. This is realized by careful control over the impregnation, calcination, and reduction steps during catalyst preparation and is identified by advanced in situ synchrotron techniques. The catalyst propane dehydrogenation performance continuously improves with increasing Cu:Pt atomic ratio.

A convenient method for the synthesis of 2 nm supported bimetallic nanoparticle Pt-Cu catalysts for propane dehydrogenation is reported here. In situ synchrotron X-ray techniques allow for the determination of the catalyst structure, which is typically unobtainable using laboratory instruments.

Síntese e Teste de Solução Sólida de Pt-Cu Suportada Catalisadores de Nanopartículas para Desidrogenação de Propano

A convenient method for the synthesis of bimetallic Pt-Cu catalysts and performance tests for propane dehydrogenation and characterization are ...

Synthesis of High Purity Nonsymmetric Dialkylphosphinic Acid Extractants

We present the synthesis of (2,3-dimethylbutyl)(2,4,4&#39;-trimethylpentyl)phosphinic acid as an example to demonstrate a method for the synthesis of high purity nonsymmetric dialkylphosphinic acid extractants. Low toxic sodium hypophosphite was chosen as the phosphorus source to react with olefin A (2,3-dimethyl-1-butene) to generate a monoalkylphosphinic acid intermediate. Amantadine was adopted to remove the dialkylphosphinic acid byproduct, as only the monoalkylphosphinic acid can react with amantadine to form an amantadine&#8729;mono-alkylphosphinic acid salt, while the dialkylphosphinic acid cannot react with amantadine due to its large steric hindrance. The purified monoalkylphosphinic acid was then reacted with olefin B (diisobutylene) to yield nonsymmetric dialkylphosphinic acid (NSDAPA). The unreacted monoalkylphosphinic acid can be easily removed by a simple base-acid post-treatment and other organic impurities can be separated out through the precipitation of the cobalt salt. The structure of the (2,3-dimethylbutyl)(2,4,4&#39;-trimethylpentyl)phosphinic acid was confirmed by 31P NMR, 1H NMR, ESI-MS, and FT-IR. The purity was determined by a potentiometric titration method, and the results indicate that the purity can exceed 96%.

A protocol for the synthesis of high purity nonsymmetric dialkylphosphinic acid extractants is presented, taking (2,3-dimethylbutyl)(2,4,4&#39;-trimethylpentyl)phosphinic acid as an example.

Síntese de alta pureza da gravitação assimétrica Dialkylphosphinic ácido Extractants

We present the synthesis of (2,3-dimethylbutyl)(2,4,4&#39;-trimethylpentyl)phosphinic acid as an example to demonstrate a method for the synthesis of high ...

Continuous Flow Chemistry: Reaction of Diphenyldiazomethane with p-Nitrobenzoic Acid

Continuous flow technology has been identified as instrumental for its environmental and economic advantages leveraging superior mixing, heat transfer and cost savings through the &#34;scaling out&#34; strategy as opposed to the traditional &#34;scaling up&#34;. Herein, we report the reaction of diphenyldiazomethane with p-nitrobenzoic acid in both batch and flow modes. To effectively transfer the reaction from batch to flow mode, it is essential to first conduct the reaction in batch. As a consequence, the reaction of diphenyldiazomethane was first studied in batch as a function of temperature, reaction time, and concentration to obtain kinetic information and process parameters. The glass flow reactor set-up is described and combines two types of reaction modules with &#34;mixing&#34; and &#34;linear&#34; microstructures. Finally, the reaction of diphenyldiazomethane with p-nitrobenzoic acid was successfully conducted in the flow reactor, with up to 95% conversion of the diphenyldiazomethane in 11 min. This proof of concept reaction aims to provide insight for scientists to consider flow technology&#39;s competitiveness, sustainability, and versatility in their research.

Continuous Flow Chemistry: Reaction of Diphenyldiazomethane with p-Nitrobenzoic Acid

Flow chemistry carries environmental and economic advantages by leveraging superior mixing, heat transfer and cost benefits. Herein, we provide a blueprint to transfer chemical processes from batch to flow mode. The reaction of diphenyldiazomethane (DDM) with p-nitrobenzoic acid, conducted in batch and flow, was chosen for proof of concept.

Química de Fluxo Contínuo: Reação de Difenildiazometano com Ácido p-Nitrobenzoico

Continuous flow technology has been identified as instrumental for its environmental and economic advantages leveraging superior mixing, heat transfer and ...

Chemical Precipitation Method for the Synthesis of Nb2O5 Modified Bulk Nickel Catalysts with High Specific Surface Area

We demonstrate a method for the synthesis of NixNb1-xO catalysts with sponge-like and fold-like nanostructures. By varying the Nb:Ni ratio, a series of NixNb1-xO nanoparticles with different atomic compositions (x = 0.03, 0.08, 0.15, and 0.20) have been prepared by chemical precipitation. These NixNb1-xO catalysts are characterized by X-ray diffraction, X-ray photoelectron spectroscopy, and scanning electron microscopy. The study revealed the sponge-like and fold-like appearance of Ni0.97Nb0.03O and Ni0.92Nb0.08O on the NiO surface, and the larger surface area of these NixNb1-xO catalysts, compared with the bulk NiO. Maximum surface area of 173 m2/g can be obtained for Ni0.92Nb0.08O catalysts. In addition, the catalytic hydroconversion of lignin-derived compounds using the synthesized Ni0.92Nb0.08O catalysts have been investigated.

Chemical Precipitation Method for the Synthesis of Nb2O5 Modified Bulk Nickel Catalysts with High Specific Surface Area

A protocol for the synthesis of sponge-like and fold-like Ni1-xNbxO nanoparticles by chemical precipitation is presented.

Método de precipitação química para a síntese do Nb2O5 modificado catalisadores de níquel em massa com alta área de superfície específica

We demonstrate a method for the synthesis of NixNb1-xO catalysts with sponge-like and fold-like nanostructures. By varying the Nb:Ni ratio, a series of ...

Preparation of Polyoxometalate-based Photo-responsive Membranes for the Photo-activation of Manganese Oxide Catalysts

This paper presents a method to prepare charge-transfer chromophores using polyoxotungstate (PW12O403-), transition metal ions (Ce3+ or Co2+), and organic polymers, with the aim of photo-activating oxygen-evolving manganese oxide catalysts, which are important components in artificial photosynthesis. The cross-linking technique was applied to obtain a self-standing membrane with a high PW12O403- content. Incorporation and structure retention of PW12O403- within the polymer matrix were confirmed by FT-IR and micro-Raman spectroscopy, and optical characteristics were investigated by UV-Vis spectroscopy, which revealed successful construction of the metal-to-metal charge transfer (MMCT) unit. After deposition of MnOx oxygen evolving catalysts, photocurrent measurements under visible light irradiation verified the sequential charge transfer, Mn &#8594; MMCT unit &#8594; electrode, and&#160;the photocurrent intensity was consistent with the redox potential of the donor metal (Ce or Co). This method provides a new strategy for preparing integrated systems involving catalysts and photon-absorption parts for use with photo-functional materials.

Here, we present a protocol to prepare charge transfer chromophores based on a polyoxometalate/polymer composite membrane.

Preparação de membranas de foto-sensível com base em germânio para a foto-ativação de catalisadores de óxido de manganês

This paper presents a method to prepare charge-transfer chromophores using polyoxotungstate (PW12O403-), transition metal ions (Ce3+ or Co2+), and organic ...