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Ethylene glycol/methanol ratio

Several differences between the cobalt- and rhodium-catalyzed processes are noteworthy with regard to mechanism. Although there is a strong dependence in the cobalt system of the ethylene glycol/methanol ratio on temperature, CO partial pressure, and H2 partial pressure, these dependences are much lower for the rhodium catalyst. Details of the product-forming steps are therefore perhaps quite different in the two systems. It is postulated for the cobalt system that the same catalyst produces all of the primary products, but there seems to be no indication of such behavior for the rhodium system. Indeed, the multiplicity of rhodium species possibly present during catalysis and the complex dependence on promoters make it... [Pg.374]

Fig. 3. Viscosity of water-ethylene glycol-methanol mixtures as a function of temperature. Numbers indicate the volume ratio for each mixture. From Travers et al. (1975). Reprinted with permission of Biochimie. Copyright by die Societe de Chimie Biologique. Fig. 3. Viscosity of water-ethylene glycol-methanol mixtures as a function of temperature. Numbers indicate the volume ratio for each mixture. From Travers et al. (1975). Reprinted with permission of Biochimie. Copyright by die Societe de Chimie Biologique.
With the development of the potentiometric technique as describe above, paH determinations can now be made very quickly and easily. This makes the screening of any buffer system in any mixed solvent much easier. Data concerning the paH of three buffer systems (cacodylate, phosphate, Tris) in three mixed solvents of water with ethylene glycol, methanol, glycerol at different volume ratios between +20° and their freezing points are summarized in Tables XXIII—... [Pg.111]

Numerous chemical intermediates are oxygen rich. Methanol, acetic acid and ethylene glycol show a O/C atomic ratio of 1, as does biomass. Other major chemicals intermediates show a lower O/C ratio, typically between 1/3 and 2/3. This holds for instance for propene and butene glycols, ethanol, (meth)acrylic acids, adipic acid and many others. The presence of some oxygen atoms is required to confer the desired physical and chemicals properties to the product. Selective and partial deoxygenation of biomass may represent an attractive and competitive route compared with the selective and partial oxidation of hydrocarbon feedstock. [Pg.28]

Water was used as the catalyst phase for the palladiiun complex of TPPTS and toluene or an excess of the substrate anihne served as the non-polar product phase. To determine an appropriate solvent system cloud titrations were performed at 90 °C, 60 °C, 40 °C and 25 °C. A solution of 4-chloro-nitroben-zene in aniline and water were mixed in a weight ratio of 1 1 and semi-polar solvents were added as a mediator until a homogeneous solution was formed. As the mediator the following solvents were apphed methanol, ethanol, isopropyl alcohol, n-butanol, DMF, DMSO, ethylene glycol, N-methylpyrrohdone (NMP), 1.4-dioxane and acetonitrile. The cloud titrations were repeated whereby the substrate 4-chloro-nitrobenzene was replaced with the product 4-nitrodiphenylamine. In all cases more of the semi-polar mediator is required for the product mixture at 25 °C than for the reaction mixture at 60 °C to obtain a clear solution. [Pg.34]

Developed by Whinfield and Dixon in the U.K. Originally made by transesterification of DMT and ethylene glycol in a 1 2.4 ratio, distillation of the methanol, then polymerization at 200-290°C in vacuo with SbOs as catalyst. [Pg.326]

Mole ratio of ethylene glycol-derived products to methanol-derived products. [Pg.336]

Fig. 7. Effect of amine/Rh ratio on product rates ( ) methanol ( ) ethylene glycol. Reaction conditions 75 ml sulfolane, 3 mmol Rh, 544 atm, H2/CO = 1, 240 C, 4 hr (109). Upper graph is for l,4-diazabicyclo[2.2.2]octane (dabco) lower graph is for Af-methylmor-pholine. Fig. 7. Effect of amine/Rh ratio on product rates ( ) methanol ( ) ethylene glycol. Reaction conditions 75 ml sulfolane, 3 mmol Rh, 544 atm, H2/CO = 1, 240 C, 4 hr (109). Upper graph is for l,4-diazabicyclo[2.2.2]octane (dabco) lower graph is for Af-methylmor-pholine.
Fig. 9. Plot of rates as a function of PPN + /Rh ratio ( ) methanol ( ) ethylene glycol. PPN ace I ate was used as promoter (102). Reaction conditions are the same as those of Fig. 8. Fig. 9. Plot of rates as a function of PPN + /Rh ratio ( ) methanol ( ) ethylene glycol. PPN ace I ate was used as promoter (102). Reaction conditions are the same as those of Fig. 8.
The amount of ethylene glycol product formed in acetic acid solvent is usually minor relative to the methanol product. Table XIV, for example, shows examples in which the CJC2 product ratio is within the range of about 35-90. Esters of the three-carbon polyalcohol, glycerol, have also been... [Pg.377]

Figure 10.11. Power consumption, (a) Ratio of power consumptions of aerated and unaerated liquids. Q is the volumetric rate of the gas (O) glycol ( X ) ethanol ( ) water. [After Calderbank, Trans. Inst. Chem. Eng. 36, 443 (1958)]. (b) Ratio of power consumptions of aerated and unaerated liquids at low values otQ/Nd3. Six-bladed disk turbine ( ) water ( ) methanol (10%) (A) ethylene glycol (8%) (A) glycerol (40%) Pg = gassed power input P = ungassed power input Q = gas flow rate IV = agitator speed d = agitator-impeller diameter. [Luong and Volesky, AIChE J. 25, 893 (1979)]. Figure 10.11. Power consumption, (a) Ratio of power consumptions of aerated and unaerated liquids. Q is the volumetric rate of the gas (O) glycol ( X ) ethanol ( ) water. [After Calderbank, Trans. Inst. Chem. Eng. 36, 443 (1958)]. (b) Ratio of power consumptions of aerated and unaerated liquids at low values otQ/Nd3. Six-bladed disk turbine ( ) water ( ) methanol (10%) (A) ethylene glycol (8%) (A) glycerol (40%) Pg = gassed power input P = ungassed power input Q = gas flow rate IV = agitator speed d = agitator-impeller diameter. [Luong and Volesky, AIChE J. 25, 893 (1979)].

See other pages where Ethylene glycol/methanol ratio is mentioned: [Pg.81]    [Pg.30]    [Pg.102]    [Pg.336]    [Pg.351]    [Pg.354]    [Pg.355]    [Pg.81]    [Pg.30]    [Pg.102]    [Pg.336]    [Pg.351]    [Pg.354]    [Pg.355]    [Pg.374]    [Pg.236]    [Pg.236]    [Pg.6381]    [Pg.100]    [Pg.129]    [Pg.33]    [Pg.665]    [Pg.81]    [Pg.29]    [Pg.300]    [Pg.347]    [Pg.353]    [Pg.358]    [Pg.361]    [Pg.376]    [Pg.391]    [Pg.396]    [Pg.397]    [Pg.397]    [Pg.446]    [Pg.447]    [Pg.269]    [Pg.59]    [Pg.66]    [Pg.210]    [Pg.189]    [Pg.169]    [Pg.450]   


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