Continuous organic electrochemical synthesis

Technical Report · Sun Jul 01 04:00:00 EDT 1984

OSTI ID:6517210

Nobe, K; Baizer, M; Pintauro, P; Park, K; Gilbert, S

The electrochemical oxidation of glucose to gluconic acid and reduction of glucose to sorbitol has been successfully paired in an undivided packed bed electrode flow cell. The use of a Raney nickel powder catalytic cathode significantly improved the current efficiency for sorbitol production, as compared to a high hydrogen overpotential Zn(Hg) cathode. The optimum operating conditions for the paired synthesis are: activity W-2 Raney nickel powder cathode, graphite chip anode, a 1.6 M glucose and 0.4 M CaBr/sub 2/ initial solution composition, pH 6-7, 60/sup 0/C solution temperature, a current density of 250 to 500 mA and a solution volumetric flow rate of 100 ml min/sup -1/. Under these conditions the sorbitol current efficiencies are at least 80%, the glucose acid current efficiencies are 100% and the product yields are quantitative. A separation scheme for the paired synthesis has also been devised. It consists of the precipitation of the oxidation product (calcium gluconate) and the ethanol extraction of glucose and CaBr/sub 2/ from sorbitol. Based on a preliminary economic analysis of the cost of raw materials, energy and the electrochemical cell and separation equipment the cost of producing 1 lb calcium gluconate and 0.68 lb sorbitol in a paired synthesis was estimated to be $0.896. The cost of producing the same amount of sorbitol and calcium gluconate in separate electrochemical cells was calculated to be $1.20. Thus, the paired synthesis appears to be an economically viable process.

• Research Organization: California Univ., Los Angeles (USA)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 6517210
• Report Number(s): LBL-18133; ON: DE85001400
• Country of Publication: United States
• Language: English

Related Subjects

25 ENERGY STORAGE
250800* -- Energy Storage-- Chemical
ALDEHYDES
CARBOHYDRATES
CARBON
CARBOXYLIC ACIDS
CATHODES
CHEMICAL REACTIONS
CHEMISTRY
DIURETICS
DRUGS
ECONOMIC ANALYSIS
ECONOMICS
ELECTROCHEMISTRY
ELECTRODES
ELEMENTAL MINERALS
ELEMENTS
GLUCONIC ACID
GLUCOSE
GRAPHITE
HEXOSES
HYDROXY ACIDS
MINERALS
MONOSACCHARIDES
NONMETALS
ORGANIC ACIDS
ORGANIC COMPOUNDS
OXIDATION
REDUCTION
SACCHARIDES
SORBITOL
SYNTHESIS