Alcohol steam reforming

Rare earth oxides are useful for partial oxidation of natural gas to ethane and ethylene. Samarium oxide doped with alkali metal halides is the most effective catalyst for producing predominantly ethylene. In syngas chemistry, addition of rare earths has proven to be useful to catalyst activity and selectivity. Formerly thorium oxide was used in the Fisher-Tropsch process. Recently ruthenium supported on rare earth oxides was found selective for lower olefin production. Also praseodymium-iron/alumina catalysts produce hydrocarbons in the middle distillate range. Further unusual catalytic properties have been found for lanthanide intermetallics like CeCo2, CeNi2, ThNis- Rare earth compounds (Ce, La) are effective promoters in alcohol synthesis, steam reforming of hydrocarbons, alcohol carbonylation and selective oxidation of olefins. 

Our ancestors made vinegar by aerobic bacterial fermentation of alcohol, which is derived from sugar, while it is now made by carbonylation of methanol, which is derived by reaction of synthesis gas, which is obtained by steam reforming of methane. 

Methanol Formaldehyde Ethylene Propylene oxide Phenol 1,4-Butanediol Tetrahydrofuran Ethylene glycol Adipic acid Isocyanates Styrene Methyl methacrylate Methyl formate Two-step, via CH4 steam reforming Three-step, via methanol Cracking of naphtha Co-product with t-butyl alcohol or styrene Co-product with acetone Reppe acetylene chemistry Multi-step Hydration of ethylene oxide Multi-step Phosgene chemistry Co-product with propylene oxide Two-step, via methacrolein Three-step, via methanol... 

Today, the United States is using some 9 billion cubic feet of H2 a day in the petrochemical, food, and rocket propulsion industries. Around 98% of the bulk H2 is produced by steam reformation of natural gas (e.g., methane). Methane is reacted with water vapor over a catalyst to form carbon monoxide (CO) and H2. H2 can also be made from ethanol (alcohol), biomass, fossil fuels, or organic waste by the process of "reforming." Most of the currently operating H2 production plants depend on reforming natural gas. This is a process that emits C02 while consuming a nonrenewable fossil... 

Methanol is the most electro-reactive organic fuel, and, when it is electro-oxidized directly at the fuel anode (instead of to be transformed by steam reforming in a hydrogen-rich gas), the fuel cell is called a DMFC. More generally if the direct oxidation of a given fuel (alcohols, borohydrides, etc.)... 

An important possible future use for pure hydrogen is in proton-exchange-membrane fuel cells (PEMFCs) the basic source for the hydrogen could be either a hydrocarbon or an alcohol, either of which can be steam-reformed to produce water-gas.16,17 As explained above, the equilibrium concentration of carbon monoxide decreases as the temperature falls (Figure 10.1), but as little as 1% is detrimental to the operation of platinum-based catalysts in a fuel cell. Excess water, which is commonly used,18 serves to move the... 

Skeletal Cu-Zn catalysts show great potential as alternatives to coprecipitated Cu0-Zn0-Al203 catalysts used commercially for low temperature methanol synthesis and water gas shift (WGS) reactions. They can also be used for other reactions such as steam reforming of methanol, methyl formate production by dehydrogenation of methanol, and hydrogenolysis of alkyl formates to produce alcohols. In all these reactions zinc oxide-promoted skeletal copper catalysts have been found to have high activity and selectivity. 

Applications of HT-type catalysts, prepared by the above methods, have been reported in recent years for basic catalysis (polymerization of alkene oxides, aldol condensation), steam reforming of methane or naphtha, CO hydrogenation as in methanol and higher-alcohol synthesis, conversion of syngas to alkanes and alkenes, hydrogenation of nitrobenzene, oxidation reactions, and as a support for Ziegler-Natta catalysts (Table 2). 

The selective oxidation or preferential oxidation of CO in hydrogen-rich stream is another important object for ceria based catalysts. The gas mixture from steam reforming/partial oxidation of alcohols or hydrocarbons, followed by the WGS reaction contains mainly FI2, CO2 and a small portion of CO, H2O, and N2. When such gaseous stream would be taken as input for hydrogen fuel cells, the CO has to be removed to avoid poisoning of the anode electrocatalysts. Ceria based nanomaterials, such as ceria/gold, ceria/copper oxide catalysts exhibit suitable catalytic activities and selectivities for CO PROX process. 

Indirect processes for converting natural gas to alcohols and higher hydrocarbons require the initial conversion of methane to synthesis gas (CO/H2). This is a difficult and expensive step normally carried out by steam reforming and partial oxidation (6). Subsequent synthesis gas conversion steps, such as FT synthesis and related processes (1,2), must occur with high selectivity to desired products in order to minimize extensive recycle of undesired products to the initial synthesis gas generation step. C5+ paraffins, low- and intermediate-molecular-weight olefins, and C20+ linear hydrocarbons provide useful feeds in downstream processes leading to fuels and petrochemicals. 

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