Bipolar electrodialysis for glycerin production from diester wastes

doi:10.1016/S0015-1882(03)00037-5

Filtration & Separation

Volume 40, Issue 10, December 2003, Pages 35-39

https://doi.org/10.1016/S0015-1882(03)00037-5 Get rights and content

Abstract

Diester plants produce large quantities of glycerin solutions, whose commercial exploitation requires sodium sulphate elimination. Bipolar electrodialysis (BED) has been investigated for its capability to both demineralize solutions and to produce alkali and acid solutions. Demineralization rates above 80% were achieved with glycerin loss below 2%. Alkali and acid solutions were obtained with a final concentration of about 2 N and an energy cost of about 0.5 kWh/kg of pure glycerin. The treatment of waste solutions could be realized with a membrane area of 100 m². Economic evaluation demonstrates the suitability of BED since demineralization allows the upgraded solution to be sold at a price 1.4 times higher than the initial solution.

Section snippets

Apparatus

The experimental set up consists of an electrodialysis stack, a power supply (Tacussel SDR 10-150), an integrator (Tacussel IG 6N), an ammeter (multimeter Metrix) and a voltmeter (multimeter Metrix).

The bipolar electrodialyser EUR2C-7bip (Eurodia) was a filter press type, made of seven elementary cells, with three compartments and two electrode compartments at each end of the stack. The three compartments were acid compartments limited by an AEM and a cationic face of bipolar membrane, an

Glycerin loss

Glycerin loss increases with treatment time, indicating that glycerin transfer occurs by diffusion. Diffusion forces push glycerin from the salt compartment to the acid and the alkali compartments. Glycerin loss in the acid compartments is not of importance because this issue re-enters the glycerin purification loop, whereas the glycerin in the alkali is completely lost. Total glycerin loss is about 15% with the ACM/CMB/BP-1 membranes while only 2% with the AMX/CMB/BP-1 membranes. Analysis of

Conclusion

The EUR2C-7bip electrodialyser allows 80% demineralization of 65% glycerin solution. After concentration, 95% glycerin solution can be obtained with less than 2% mineral content. The pH of this solution is highly acidic (pH = 1).

Sulphuric acid and sodium hydroxide have a molarity between 2 -4M. Higher concentration could be achieved, but with a decrease in faradic efficiency. The faradic efficiencies achieved are 47% and 35% for acid concentrations of 2 M and 3 M, respectively. The higher the

Acknowledgements

The authors wish to thank ONIDOL and NOVANCE for their financial and technical support during this project.

References (17)

S Resbeut et al.
Electromembrane processes for waste stream treatment: electrodialysis applied to the demineralization of phenylalanine solutions
Desalination
(1998)
S Novalic et al.
Separation of gluconate with conventional and bipolar electrodialysis
Desalination
(1997)
S Parulekar
Optimal current and voltage trajectories for minimum energy consumption in batch electrodialysis
J. Membrane Science
(1998)
L Bazinet et al.
Bipolar-membrane: applications of electrodialysis in the food industry
Trends Food Science Technology
(1998)
R Stern et al.
Gasoils de substitution à partir d'esters d'huiles végétales: une opportunité pour certains pays?
Revue de l'Institut Français du Pétrole
(1988)
G Sonntag
Glycerin
A key Cosmetic Ingedient
(1991)
F Schaffner
Déminéralisation par électrodialyse des effluents de fabrication du diester
INPT thesis
(1997)
F Schaffner et al.
Electrodialysis of crude glycerin recovered after esterification of colza oil
Proceeding of the 7th World Filtration Congress
(1998)

There are more references available in the full text version of this article.

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Research articleBipolar electrodialysis for glycerin production from diester wastes

Abstract

Section snippets

Apparatus

Glycerin loss

Conclusion

Acknowledgements

Desalination

Desalination

J. Membrane Science

Trends Food Science Technology

Gasoils de substitution à partir d'esters d'huiles végétales: une opportunité pour certains pays?

Revue de l'Institut Français du Pétrole

Glycerin

A key Cosmetic Ingedient

Déminéralisation par électrodialyse des effluents de fabrication du diester

INPT thesis

Electrodialysis of crude glycerin recovered after esterification of colza oil

Proceeding of the 7th World Filtration Congress

Research article
Bipolar electrodialysis for glycerin production from diester wastes