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Higher alcohols production

Selectivity is primarily a function of temperature. The amount of by-products tends to increase as the operating temperature is raised to compensate for declining catalyst activity. By-product formation is also influenced by catalyst impurities, whether left behind during manufacture or otherwise introduced into the process. Alkaline impurities cataly2e higher alcohol production whereas acidic impurities, as well as trace iron and nickel, promote heavier hydrocarbon formation. [Pg.276]

In CO hydrogenation, the achvity and selechvity to C1-C5 oxygenates over the bimetallic samples are higher than those of the monometallic counterparts [187-190]. Bimetallic catalysts also showed improved activity in the hydroformylation of ethylene compared to either of the monometallic catalysts [191]. The promotion for higher alcohol production is proposed to be associated with the adjacent Ru-Co sites. However, the lack of an exhaustive characterization of catalysts does not allow a clear correlation to be established between the characteristics of the active sites and the catalytic behavior. A formyl species bonded to a Ru-Co bimetallic site has been proposed to be the intermediate in the alcohol synthesis in these systems. A subsequent reaction with an alkyl-surface group would lead to the C2-oxygenate production [187]. [Pg.336]

In many of the experiments, a small amount of the 2-methylpropanal (isobutyraldehyde) intermediate was formed. The amounts were determined and are reported in Tables 1,2, and 4-10. Only in two of the experiments were formaldehyde and acetaldehyde analyzed, but it is assumed that small amounts of formaldehyde were present in all of the products. Other aldehyde intermediates, such as propanal and 2-methylbutanal, were not present in amounts large enough for detection. Besides the major higher-alcohol products and aldehyde intermediates described above, some other minor products were determined in the chromatograms of each product. These include esters, ethers, and aromatics formed in very small amounts. The sums of these are reported in Tables 1,2, and 4-10 as "Other." The areas of these GC peaks were converted to millimoles by using approximate response factors appropriate for the molecular weight range of the peaks. [Pg.920]

The composite was very low in ethanol, so the conversion was naturally 100% in the recycle run. The recycled feed produced a very high yield of 2-methyl-l-propanol. The reaction also resulted in an increased formation of 2-methylpropanal. Thus, recycling of the lower alcohols containing some lower aldehydes should be effective for increasing higher-alcohol product yields, but this experiment has not yet been completed. [Pg.927]

Bertolini, L., Zambonelli, C., Giudici, P., and Castellari, L. (1996). Higher alcohol production by cryotolerant Saccharomyces strains. Am. ]. Enol. Vitic. 47, 343-345. [Pg.197]

With regards to fusel alcohol production, Kunkee and Goswell (5) noted that while yeast strain appeared to have an effect on fusel alcohol production, other factors, notably must composition, appeared to have equally important influences. For example. Berry and Watson (29) reported that added nitrogen and carbohydrates can stimulate higher alcohol production, as can increased pH (59). Various processing parameters can also affect fusel alcohol production, including agitation, aeration, and temperature (29,59). [Pg.74]

Methanol and higher alcohol production from syngas. [Pg.249]

Kodama, Y, Omura, F., Miyajima, K., Ashikari, T. (2001). Control of higher alcohol production by manipulation of the BAP2 gene in brewing yeast. Journal of the American Society of Brewing Chemists, 59,157-162. [Pg.62]

Just recently, Huo et al. (2011, 2012) engineered E. coli for the protein-based higher alcohol production. This was achieved by directed evolution using chemical... [Pg.346]

Higher alcohols Using EMA to guide strain design for improved higher alcohols production. No Matsuda et al. (2011) 1. CO... [Pg.31]

Higher alcohol production by yeasts appears to be linked not only to the catabolism of amino acids but also to their synthesis via the corresponding ketonic acids. These acids are derived from the metabolism of sugars. For example, propan-l-ol has no corresponding amino acid. It is derived from a-ketobutyrate which can be formed from pyruvate and acetyl coenzyme A. a-Ketoisocaproate is a precursor of isoamylic alcohol and an intermediary product in the synthesis of leucine. It too can be produced from a-acetolactate, which is derived from pyruvate. Most higher alcohols in wine can also be formed by the metabolism of glucose without the involvement of amino acids. [Pg.74]

The physiological function of higher alcohol production by yeasts is not clear. It may be a simple waste of sugars, a detoxification process of the intracellular medium, or a means of regulating the metabolism of amino acids. [Pg.76]

The winemaking parameters that increase higher alcohol production by yeasts are well known high pH, elevated fermentation temperature, and aeration. In red winemaking, the extraction of pomace constituents and the concern for rapid and complete fermentations impose aeration and elevated temperatures, and in this case higher alcohol production by yeast cannot be limited. In white winemaking, a fermentation temperature between 20 and 22° C limits the formation of higher alcohols. [Pg.76]

Guymon etal., 1961). Yet production by wine yeasts is limited, even in spontaneous fermentation. More recently, various researchers have shown that most S. bayanus (ex uvarum) produce considerably more phenylethanol than S. cerevisiae. Finally, higher alcohol production in S. cerevisiae depends on the strain. A limited higher alcohol production (with the exception of phenylethanol) should be among selection criteria for wine yeasts. [Pg.76]


See other pages where Higher alcohols production is mentioned: [Pg.446]    [Pg.135]    [Pg.913]    [Pg.916]    [Pg.916]    [Pg.917]    [Pg.926]    [Pg.927]    [Pg.930]    [Pg.163]    [Pg.191]    [Pg.446]    [Pg.335]    [Pg.335]    [Pg.369]    [Pg.157]    [Pg.446]    [Pg.209]    [Pg.331]    [Pg.370]    [Pg.39]    [Pg.431]    [Pg.85]   
See also in sourсe #XX -- [ Pg.157 ]

See also in sourсe #XX -- [ Pg.274 , Pg.278 ]




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Alcohols production

Methanol Production and Higher Alcohols from Syngas

Methylated Products and Homologation to Higher Alcohols

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