Methanol partial oxidation

As discussed in Chapter 3, the controversial argument about the strongly adsorbed poisonous spedes of methanol partial oxidation is almost settled, resvilting in the condusion that COad is at least one of the msgor adsorbates. Therefore, both for understanding the mechanisms of methanol oxidation and for searching for new catalysts, it is very important to understand the behavior of COad under various conditions. 

E. Yu. Batyan, S. V. Matveichuk, and G. A. Branitskii, Structural phase transformations in silver-ceramic systems and their relation to catalytic properties in the process of methanol partial oxidation, Kinet. Catal. 136, 816-820 (1995). 

The use of Cl sources in applied catalysis research has grown enormously in the past few years. The fact, that methanol can be conveniently synthesized from methane or coal, has promoted research into the reactions involving methanol. Partial oxidation of methanol to H2... 

Fig. 41. Methanol partial oxidation over M0O3 at 300°C. FA, formaldehyde DME, dimethyl ether. Starting with the approximately stoichiometric oxide, the feed is changed as shown A, 3.6% methanol/helium B, 10% oxygen/helium C, 3.6% methanol/10% oxygen/ helium (after 249).

S. Ahmed, R. Kumar, and M. Krumpelt, Methanol Partial Oxidation Reformer, US Patent 6,244,367 issued June 12, 2001. 

The main problems regarding the replacement of batteries by direct alcohol fuel cells are related to the largest volume required by the fuel cells, as compared to the batteries which have become highly compact (because DAFCs have not reached yet high efficiencies), elimination of residues of the methanol partial oxidation (generally mixtures of water with formic acid, methyl formate, and formaldehyde), and the high temperature which can reach the DAFC (up to around 85 °C for cells using Nafion membranes) [11, 12]. 

Two process variants are used for the manufacture of formaldehyde from methanol, partial oxidative dehydrogenation or oxidation. In the first, methanol vapour is mixed with a stoichiometrically deficient quantity of air and passed over a silver catalyst at temperatures of 400-600°C. The two reactions... 

Figure 7,7 (a) a plot of minimum reactor volume versus Pd requirements compares methanol reforming on Cu/Zn0/Al20 and methanol decomposition on Pd/Si02- Thin Pd membranes and fibre supports lead to reduced volume and Pd needs, (b) a plot of minimum reactor volume versus Pd requirements compares methanol reforming on Cu/Zn0/Al202 with methanol partial oxidation on CU/AI2O, (Source After Ref [108])... 

Wanat et al. investigated methanol partial oxidation over various rhodium containing catalysts on ceramic monoliths, namely rhodium/alumina, rhodium/ceria, rhodium/ruthenium and rhodium/cobalt catalysts [195]. The rhodium/ceria sample performed best. Full methanol conversion was achieved at reaction temperatures exceeding 550 °C and with O/C ratios of from 0.66 to 1.0. Owing to the high reaction temperature, carbon monoxide selectivity was high, exceeding 70%. No by-products were observed except for methane. 

Selectivity of methanol partial oxidation with O2 in SCCO2 at 200-300°C, using iron-based aerogels can be shifted towards either dimethyl ether (70%), formaldehyde or methyl formate as the predominant products depending on the reaction conditions and catalyst. Though methanol conversion was lower than in the gas-phase process, the production of desired ether, aldehyde and ester in the SCF process is higher. 

Selectivity toward methanol partial oxidation products (famaldehyde, methyl formate, and dimethoxy methane) at 300°C. 

C.T. Wang and R.J. Willey, (2001) Mechanistic aspects of methanol partial oxidation over supported iron oxide aerogel . Journal of Catalysis, 202(2)211-219. 

Only a few studies on the oxidative methanol SR for hydrogen production are present in the literature. Murcia-Mascaros et al (2001), for example, proposed the oxidative methanol SR as a combination of methanol SR with methanol partial oxidation ... 

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