Catalyst methanol

Robert Boyle, an Irish chemist noted for his pioneering experiments on the properties of gases, discovered methanol (CH3OH) in 1661. For many years methanol, known as wood alcohol, was produced by heating hardwoods such as maple, birch, and hickory to high temperatures m the absence of air. The most popular modern method of producing methanol, which IS also the least costly, is from natural gas (methane) by the direct combination of carbon monoxide gas and hydrogen in the presence of a catalyst. Methanol also can be produced more expensively from oil, coal, and biomass. 

The formation of DME is a result of the selection of adequate catalysts. Methanol and DME plants achieve similar total process energy efficiencies. 

Methanol, CH3OH, the simplest alcohol, is made by reacting CO and H2 at high pressures over a catalyst. Methanol is a liquid at room temperature and is highly toxic. It is used to make formaldehyde, acetic acid, and other chemical intermediates. It is also used as a feedstock for MTBE (methyl tertiary butyl ether), a gasoline-blending component. 

For these low-temperature fuel cells, the development of catalytic materials is essential to activate the electrochemical reactions involved. This concerns the electro-oxidation of the fuel (reformate hydrogen containing some traces of CO, which acts as a poisoning species for the anode catalyst methanol and ethanol, which have a relatively low reactivity at low temperatures) and the electroreduction of the oxidant (oxygen), which is still a source of high energy losses (up to 30-40%) due to the low reactivity of oxygen at the best platinum-based electrocatalysts. 

Both acid and base catalysts can be used, but base catalysts are 4000 times more active and cause fewer corrosion problems than acid catalysts. Methanol, due to its low cost, is the alcohol most commonly used up to now, with the exception of Brazil, where ethanol is preferred. Homogeneous alkaline catalysts, such as NaOH, KOH and sodium methoxide (NaOMe), are generally used. NaOMe is the most active, most... 

Activities of Group VIII Metal Catalysts. Methanol conversions to methyl acetate and acetic acid on group VIII metals supported upon activated carbon are illustrated in Figure 1, The yield was calculated as methanol conversion to acetyl group. For each catalyst, acetic acid formation is predominant at high temperature while methyl acetate has a point of maximum yield. 

Catalyst Methanol Rate of H2 evolution (ptnol h g ) Ethanol 1-Propanol 1-Butanol Ref. 

Initially, the reactor was charged with 400 g of rapeseed oil and heated to the set temperature with agitation. Catalyst was dissolved in the required amount of methanol and heated to the set temperature. After reaching the set temperature of reactant and catalyst, methanolic catalyst was added to the base of the reactor to prevent evaporation of methanol. The reaction was timed immediately after the addition of catalyst and methanol. Reaction experiment parameters were designed to determine the conversion yield of rapeseed oil (Table 2). 

Homologation is the one-carbon extension reaction of organic compounds such as alcohols and carboxylic esters, and is very important. Cobalt, rhodium, and ruthenium complexes are known to be efficient catalysts. Methanol and methyl ester can be converted to ethanol and ethyl ester, respectively, using Ru/F [28] and Ru/Co [29] catalysts (Eq. 11.9). 

Methanol conversion was adopted as a probe reaction to explore the catalytic activity of M" -TSM, because methanol is a simple molecule that transforms into easily assignable compounds and is converted into different products through different routes employing different catalysts. Methanol is decomposed into carbon monoxide and hydrogen over metal catalysts [including Ni (77)], is dehydrogenated into formaldehyde or methyl formate over Zn- or Cu-containing catalysts (78), and is dehydrated into dimethyl ether and successively into hydrocarbons over acid catalysts (79). 

Copper zinc oxide catalysts—methanol synthesis... 

The TPD curves ( methanol exposed catalysts ) from the C-C active catalyst are very different from the TPD curves from the C-C inactive catalyst (methanol exposed ). Figure 2. After TPD to > 450 °C the catalyst becomes almost inactive. It can be regenerated as above to its former activity level. 

Figure 32 shows another example of the poisoning of a Cr(VI) /silica catalyst. Methanol was added to the reactor at the beginning of the reaction in the amount of about 1 CH3OH molecule/Cr atom [377]. Again, the development of polymerization rate was delayed, but the... 

The outgassing of the catalyst-methanol system prior to reduction of the catalyst was omitted. 

Davy Process Technology, UK/Johnson Matthey Catalysts Methanol Natural gas or associated gas The process produces methanol from natural gas or associated gas via a reforming step or from syngas generated by gasification of coal, coke or biomass. The reforming/gasification step is followed by compression, methanol synthesis and distillation 87 2010... 

BP Chemicals Low Pressure Process Design. A process flow diagram for the BP Chemicals carbonylation process is shown in Figure 3 [9]. The reactor contains acetic acid, water, hydrogen iodide, methyl iodide, and the rhodium-based catalyst. Methanol is pumped to the reactor and carbon monoxide is compressed to approximately 36 bars (525 psig) and sparged into the bottom of the liquid filled reactor. 

Desorption Time. One-half to one hour with good agitation is usually sufficient desorption time for most systems. Once optimum desorption has taken place, the system is generally stable however, some exceptions have been observed Some compounds react or are readsorbed after an optimum desorption time as shown in Fig. 5. The active surface of the sorbent may act as a catalyst. Methanol has been shown to react with carbon disulfide in the presence of charcoal to form polysulfides, mercaptans and polyether-thioether compounds Decanting the solvent from the sorbent usually corrects this problem. 

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