Thermochemical reaction

In this paper selectivity in partial oxidation reactions is related to the manner in which hydrocarbon intermediates (R) are bound to surface metal centers on oxides. When the bonding is through oxygen atoms (M-O-R) selective oxidation products are favored, and when the bonding is directly between metal and hydrocarbon (M-R), total oxidation is preferred. Results are presented for two redox systems ethane oxidation on supported vanadium oxide and propylene oxidation on supported molybdenum oxide. The catalysts and adsorbates are stuped by laser Raman spectroscopy, reaction kinetics, and temperature-programmed reaction. Thermochemical calculations confirm that the M-R intermediates are more stable than the M-O-R intermediates. The longer surface residence time of the M-R complexes, coupled to their lack of ready decomposition pathways, is responsible for their total oxidation. 

For example, aldehydes and ketones react with excess alcohol to produce acetals or ketals, and organometallic additions followed by hydrolysis produce alcohols. The formal reagents X—Y for formation of acetals/ketals and substituted alcohols are thus ROR and RH, respectively. Equation 34 is a clean chemical equation, as opposed to the real chemical reactions with the accompanying complicating effects of reagents, by-products and solvents. Equation 35 expresses the reaction thermochemically. 

Other thermochemical data (e.g., heat of formation and proton affinity). These thermochemical data are very helpful to atmospheric modeling to understand the complex chemical reactions. Thermochemical data can be obtained by high levels of calculations, e.g., CCSD(T), Gn series, CBS, QCI, etc. 

Conversion of material from one form to another is a task of the chemical engineer. Table 1.3 lists a number of ways conversion can be accomplished, depending on what form of energy is supplied to the reactor. The most common form of energy is heat to carry out a reaction thermochemically. 

In Chapter 1, reactions were classed according to the form of energy supplied to the reaction thermochemical, biochemical, electrochemical, photochemi-... 

Enthalpy. Enthalpy of Reactions. Thermochemical Equations A Comparison of AH and A ... 

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