Gasoline hydrogen and

Liquefied petroleum gas (LPG) was involved in 17% of the incidents (see Chapter 8), followed by heavy oils (see Section 12.4), gasoline, hydrogen, and hydrocarbon gases. Heavy oils are involved in so many incidents because they are often handled above their auto-ignition temperature and because they are involved in foamovers. 

Table 15.7 Styrene conversion data for pyrolysis gasoline hydrogenation and synthetic load of commercial nickel and palladium catalysts after forced regeneration and shutdown...

A good catalyst is also stable. It must not deactivate at the high temperature levels (1300 to 1400°F) experienced in regenerators. It must also be resistant to contamination. While all catalysts are subject to contamination by certain metals, such as nickel, vanadium, and iron in extremely minute amounts, some are affected much more than others. While metal contaminants deactivate the catalyst slightly, this is not serious. The really important effect of the metals is that they destroy a catalyst s selectivity. The hydrogen and coke yields go up very rapidly, and the gasoline yield goes down. While Zeolite catalysts are not as sensitive to metals as 3A catalysts, they are more sensitive to the carbon level on the catalyst than 3A. Since all commercial catalysts are contaminated to some extent, it has been necessary to set up a measure that will reflect just how badly they are contaminated. 

Depending upon the refinery needs, the raw C5 plus steam cracked naphtha may be sent to isoprene extraction, treated to remove gum forming diolefins and sent to the refinery gasoline pool, or else completely hydrogenated and then fed to an aromatics extraction unit. 

Hydrogen transfer reactions usually increase gasoline yield and stability. The reactivity of the gasoline is reduced because hydrogen transfer produces fewer olefins. 

Methanol is also formed as a byproduct when charcoal is made by heating wood in the absence of air. For this reason, it is sometimes called wood alcohol. Methanol is used in jet fuels and as a solvent, gasoline additive, and starting material for several industrial syntheses. It is a deadly poison ingestion of as little as 25 mL can be fatal. The antidote in this case is a solution of sodium hydrogen carbonate, NaHC03. 

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