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Electrochemical reduction of carbon

The conventional electrochemical reduction of carbon dioxide tends to give formic acid as the major product, which can be obtained with a 90% current efficiency using, for example, indium, tin, or mercury cathodes. Being able to convert CO2 initially to formates or formaldehyde is in itself significant. In our direct oxidation liquid feed fuel cell, varied oxygenates such as formaldehyde, formic acid and methyl formate, dimethoxymethane, trimethoxymethane, trioxane, and dimethyl carbonate are all useful fuels. At the same time, they can also be readily reduced further to methyl alcohol by varied chemical or enzymatic processes. [Pg.220]

New Synthesis. Many attempts have been made to synthesize oxaUc acid by electrochemical reduction of carbon dioxide in either aqueous or nonaqueous electrolytes (53—57). For instance, oxaUc acid is prepared from CO2 as its Zn salt in an undivided ceU with Zn anodes and stainless steel cathodes ia acetonitrile containing (C4H2)4NC104 and current efficiency of >90% (53). Micropilot experiments and a process design were also made. [Pg.460]

Electrochemical reduction of carbon-fliionne bonds occurs at high pH when a carbonyl group is adjacent Polaiographic reduction of a a,a-tnfluoroacetophe-none without loss of fluonne predominates in acidic media to give the alcohol and the corresponding pinacol, whereas reduction of the unprotonated ketone results in hydrogenolysis of the tnfluoromethyl group to form acetophenone as product Il] (equation 8)... [Pg.298]

Staging phenomena as well as the degree of intercalation can be easily observed during the electrochemical reduction of carbons in Li+-containing electrolytes. Figure 6 (left) shows a schematic poten-tial/composition curve for the galvanostatic... [Pg.391]

Electrochemical reduction of carbon dioxide has found no extensive application so far, yet it is of great interest for scientists in the fields of theoretical and applied electrochemistry. To a certain extent, it is analogous to the photochemical carbon dioxide reduction, but it involves no chlorophyll and yields simpler products. In recent years some books and reviews on this topic have been published (e.g., Taniguchi, 1989 Sullivan et al., 1993 Bagotsky and Osetrova, 1995). [Pg.291]

Electrochemical reduction of carbon dioxide is usually conducted in aqueous or nonaqueous electrolyte solutions at cathodes made of various materials. As a result, various organic substances can form. The most common reactions are as follows ... [Pg.291]

Summing up, it can be said that the reaction of the electrochemical reduction of carbon dioxide will be the subject of painstaking research for a long time to come. In the future this reaction is very likely to play an important role in the electrochemical industry. [Pg.294]

Bagotsky, V. S., and N. Osetrova, Electrochemical reduction of carbon dioxide, Russ. J. [Pg.296]

Great promise exists in the use of graphitic carbons in the electrochemical synthesis of hydrogen peroxide [reaction (15.21)] and in the electrochemical reduction of carbon dioxide to various organic products. Considering the diversity in structures and surface forms of carbonaceous materials, it is difficult to formulate generalizations as to the influence of their chemical and electron structure on the kinetics and mechanism of electrochemical reactions occurring at carbon electrodes. [Pg.543]

Here, some recent studies of the electrochemical and photo-electrochemical reduction of carbon dioxide as well as some other related subjects will be reviewed and discussed. Attention is focused especially on the work done in the last ten years, to avoid duplication of previous review articles.2,4... [Pg.328]

Products Obtained by Electrochemical Reduction of Carbon Dioxide under High Pressure of 10 kg/cm2 Gagea... [Pg.334]

Mechanistic Aspects of the Electrochemical Reduction of Carbon Monoxide and Methanol to Methane at Ruthenium and Copper Electrodes... [Pg.518]

The electrochemical reduction of carbon monoxide also offers a route for the production of fuels from inorganic sources. For example, carbon monoxide is formed from coal in gasification... [Pg.518]

The electrochemical reductions of carbon monoxide and methanol to methane (Equations 1 and 2) have potentials, under standard conditions, of +0.019 and +0.390 V vs SCE respectively (or a... [Pg.519]

The direct electrochemical reduction of carbon dioxide requires very negative potentials, more negative than —2V vs. SCE. Redox catalysis, which implies the intermediacy of C02 (E° = —2.2 V vs. SCE), is accordingly rather inefficient.3 With aromatic anion radicals, catalysis is hampered in most cases by a two-electron carboxylation of the aromatic ring. Spectacular chemical catalysis is obtained with electrochemically generated iron(0) porphyrins, but the help of a synergistic effect of Bronsted and Lewis acids is required.4... [Pg.260]

Electrochemical reduction of carbon monoxide in dry nonaqueous media at moderate to low pressures leads to the formation of the 1,3-cyclobutanedione dianion (squarate) at current efficiencies, up to about 45% depending on the cathode material [1,2]. In aqueous solution, electroreduction can lead to the formation of methane and other hydrocarbon products. The role of the metal/adatom in determining the extent of CO and hence hydrocarbon formation during the reduction of carbon dioxide is related to the ability of the electrode material to favor CO formation (Cu, Au, Ag, Zn, Pd, Ga, Ni, and Pt) and stabilize HCCO [3, 4]. [Pg.226]

Many attempts have been made to synthesize oxalic acid by electrochemical reduction of carbon dioxide in either aqueous or nonaqueous electrolytes. [Pg.1184]

Tinnemans, A.H.A., Koster, T.P.M., Thewissen, D.H.M.W. and Mackor A. 1984. Tetraaza-macrocyclic cobalt(II) and nickel(II) complexes as electrontransfer agents in the photo( electro )chemical and electrochemical reduction of carbon dioxide. Recl.Trav.Chim. Pavs-Bas 103. 288-295. [Pg.7]

The electrochemical reduction of carbon diselenide in the presence of methyl iodide generated tetraselenafulvalene (107) (76CC148). Six carbon diselenide molecules were necessary for each molecule of product generated. [Pg.971]

Mahmood et al. [117] studied the electrochemical reduction of carbon dioxide using gas diffusion electrodes. The reduction was performed on metal (lead, indium, and tin)-impregnated Teflon -bonded carbon gas diffusion electrodes in a sulfuric acid electrolyte over a 1 - 5 pH range. A schematic of the cell is shown in Fig. 24. The following reactions occurred ... [Pg.404]

A recent addition to the field of functional, catalytic ionic liquids comes in the area of carbon dioxide fixation. However, in this example, the reaction was performed under solvent free conditions and the ionic liquid was just used as a catalyst. Using [Bmim][OH], yields of up to 58% were obtained for the synthesis of disubstituted ureas from amines and carbon dioxide.By considering the electrochemical reduction of carbon dioxide discussed above, it is clear that ionic liquids could have an important role to play in the area of carbon dioxide fixation. [Pg.130]

Electrochemical reduction of carbon dioxide at a platinum electrode in acetonitrile-water mixtures... [Pg.581]

I. Taniguchi, Electrochemical and photo-electrochemical reduction of carbon dioxide, in Modem Aspect of Electrochemistry, Plenum Press, New York, 1989, p. 327, Vol. 20. [Pg.85]

Japanese researchers [248] have designed an apparatus for the electrochemical reduction of carbon dioxide employing ultrasound. The apparatus comprises an electrolytic cell containing C02-dissolved electrolytic solution, a porous Pt-group metal anode, a proton-conductive solid electrolyte having a porous metal cathode used as a catalyst for the electrochemical reduction of COz on one side and a second anode on the other side facing oppositely to the cathode, and an ultrasonic vibrator. C02 can be reduced effectively for a long time. [Pg.275]

Scheme 16.14 Electrochemical reduction of carbon dioxide (Reprinted from Ref. [119] with kind... Scheme 16.14 Electrochemical reduction of carbon dioxide (Reprinted from Ref. [119] with kind...
Amatore C, Saveant JM (1981) Mechanism and kinetic characteristics of the electrochemical reduction of carbon dioxide in media of low proton avaUabiUty. J Am Chem Soc 103 ... [Pg.469]

A new method of reducing carbon dioxide/bicarbonate solutions to form methanol and other reduced products is presented. The method overcomes the traditional limitations of electrochemical reduction of carbon dioxide at a cathode in that both the surface potential and concentration of reducing species can be varied independently. [Pg.153]


See other pages where Electrochemical reduction of carbon is mentioned: [Pg.553]    [Pg.328]    [Pg.328]    [Pg.336]    [Pg.518]    [Pg.519]    [Pg.152]    [Pg.44]    [Pg.298]    [Pg.53]    [Pg.146]    [Pg.298]    [Pg.221]    [Pg.241]    [Pg.242]    [Pg.86]    [Pg.171]   


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