Hydrogen requirement

Stoichiometric factor = stoichiometric moles of hydrogen required per mole of benzene produced... 

Oxalic acid produced from syngas can be esteiified (eq. 20) and reduced with hydrogen to form ethylene glycol with recovery of the esterification alcohol (eq. 21). Hydrogenation requires a copper catalyst giving 100% conversion with selectivities to ethylene glycol of 95% (15). 

Refinery hydrogen requirement is met either by direct manufacture or indirect by-product recovery. Manufacture is typically by steam methane... 

High temperature steam reforming of natural gas accounts for 97% of the hydrogen used for ammonia synthesis in the United States. Hydrogen requirement for ammonia synthesis is about 336 m /t of ammonia produced for a typical 1000 t/d ammonia plant. The near-term demand for ammonia remains stagnant. Methanol production requires 560 m of hydrogen for each ton produced, based on a 2500-t/d methanol plant. Methanol demand is expected to increase in response to an increased use of the fuel—oxygenate methyl /-butyl ether (MTBE). 

Shale oil contains large quantities of olefinic hydrocarbons (see Table 8), which cause gumming and constitute an increased hydrogen requirement for upgrading. Properties for cmde shale oil are compared with petroleum cmde in Table 10. High pour points prevent pipeline transportation of the cmde shale oil (see Pipelines). Arsenic and iron can cause catalyst poisoning. 

There are many descriptions of various microreactors for hydrogenation. Requirements for these reactors are more exacting because of the need to measure accurately small amounts of consumed hydrogen (22,30,31,36,45,46, 49,59,69,70,91,92,104,111). 

The hydrogenation is exothermic, and care must be taken in order to prevent the reaction from getting out of control. The submitters have not experienced this difficulty, but exothermic hydrogenations require supervision. 

An overall view of the chemistry of hydrogen requires that it be classified alone—as a separate... 

Onboard hydrogen required for 500 km cruise is estimated to be 5 kg, amounting to 77.7 L of commercial decalin (cis/trans = 1) and 104.1 L of methylcyclohexane in volume, which corresponds to 1.09 and 1.52 times of the required amount of liquefied hydrogen (70.6 L), respectively. 

In a process for the production of hydrogen required for the manufacture of ammonia, natural gas is to be reformed with steam according to the reactions ... 

Hydrogen availability is an important issue and refiners must be persuaded that gasification will prove to be as reliable a technology in the future as natural gas steam reforming is today. Many refineries produce sufficient pet coke to more than satisfy refinery hydrogen requirements. This would allow co-production of hydrogen and power or F-T liquids. 

The important feature of this reaction system is its experimental simplicity.105 Although hydrogenation requires elevated pressure and high temperature, this reaction can be carried out at room temperature in an inert atmosphere. The catalyst can be activated before the addition of the substrate or, even more conveniently, in the presence of the substrate. After completion of the reaction and the subsequent acidic workup, the secondary amine product can be obtained in high yield and purity as well as very high enantioselectivity. 

Liquid hydrogen requires extreme precautions in handling because of the low temperature. Fueling is usually done mechanically with a robot arm. Even in large, centralized liquefaction units, the electric power requirement is high with 12 to 15 kilowatt-hours (kWh) needed per kilogram of hydrogen liquefied. 

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