Oxygen by-product

Reactions of /l-Butane. The most important industrial reactions of / -butane are vapor-phase oxidation to form maleic anhydride (qv), thermal cracking to produce ethylene (qv), Hquid-phase oxidation to produce acetic acid (qv) and oxygenated by-products, and isomerization to form isobutane. 

The recovery and purification facilities in such a process are complex. One reason is that oxygenated by-products are made in the reactors. Oxygenates hinder polymerization of styrene and cause coIot instability. Elaborate purification is required to remove the oxygenates. 

Input water was taken at EUR 10 m3, which directly leads to a EUR 0.1 kgH2 contribution. Oxygen by-product valorisation was discarded. Finally, somewhat optimistic values were taken for the cost of thermal energy from the V/HTR (EUR 20 MWh) and for electricity (EUR 40 MWh). 

In the analysis of the HTSE hydrogen plant, the anode air sweep option was used as the reference, and when diluted with air, by-product oxygen is not likely to be saleable, whereas in the S-I and HyS flow sheets there is a pure oxygen by-product. A further revision to the HTSE case is plotted next in Figure 1 (above 4 ) for the HTSE case of no air sweep equipment and adds sale of by-product oxygen. 

The higher oxygenate by-products (carboxylic acids, CO, CO2) are not desired these were formed as a result of too much oxidation. These compounds were formed for even the lowest reaction time of 5 sec used in this... 

Upham, B. L., Masten, S. J., Lockwood, B. R., and Trosko, J. E. (1994). Nongenotoxic effects of poly-cychc aromatic hydrocarbons and their oxygenation by-products on the intercellular communication of rat hver epithelial cells. Fundam Appl Toxicol 23(3), 470-475. 

The initial rate of formation of aryl fluoride, but also the yield of oxygenated by-products, increase with the water content of the reagent,... 

Because of the decomposition of ozone in water, some chlorine must be added to maintain disinfectant throughout the water distribution systan. Although ozone does not produce the undesirable halogenated organics that cause problems with the use of chlorine, it does produce some oxygenated by-products. These include aldehydes (acetaldehyde, H3CC(0)H) and carboxylic acids and their salts (oxalic acid, HO2CCO2H). 

---