Abstract
Selective reactions of catechol have been studied in regard to its inhibition properties towards alumina hydrate crystallization. Electrochemical reactions of the inhibitor leading to products without inhibition behaviour have been obtained using different conditions. First, a pure sodium hydroxide solution (1.0 M NaOH) was used to electrochemically react the catechol. The inhibitor reactions were then carried out in both saturated and supersaturated sodium aluminate solutions (NaAl(OH)4). Electrocatalytic hydrogenation (ECH) of the aromatic ring over rhodium-based catalysts leads to the saturated non-inhibiting molecule, 1,2-cyclohexanediol. Temperature shows no significant influence on the ECH process within the temperature range where the alumina hydrate crystallization is normally carried out. The presence of aluminate ions in solution has, however, a detrimental effect on the current efficiency. Electro-oxidation of the catechol produces muconic acid by cleavage of the carbon-carbon bound. It also produces other oxidation products and, eventually, may lead to total mineralization of catechol into carbonate, which is a less inhibiting molecule. A detrimental effect of the presence of aluminate on the electro-oxidation is also observed. Electrochemical techniques are proposed as new pathways for organic control in caustic medium.
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References
Watling H, Loh J, Gatter H (2000) Hydrometallurgy 55:275
Watling H (2000) Hydrometallurgy 55:289
Watling HR, Townsend R, Loh JSC (1999) Industrial Crystallization, 1
Smith PG, Watling HR, Crew P (1996) Colloids Surf A Physicochem Eng Asp 111:119
Picard F, Audet D, Boily H, Larocque J (2002) Identification of hydrate active organics (HAO) present in spent bayer liquors by state-of-the-art analytical methods, Proceedings of the 6th International Alumina Quality Workshop, Brisbane, Australia, p 46
Armstrong L (1993) Bound soda incorporation during hydrate precipitation, Proceedings of the 3rd International Alumina Quality Workshop. HunterValley, Australia, p 283
Bouchard NA, Breault R, Picard F, Chouinard Y, Ménard H (2005) Light Metals, 197
Joglekar HS, Samant SD, Joshi JB (1991) Water Res 25:135
Nematollahi D, Alimoradi M, Husain SW (2004) Electroanalysis 16:1359
da Silva LM, De Faria LA, Boodts JFC (2003) Electrochim Acta 48:699
Fleischmann M, Korinek K, Pletcher D (1971) J Electroanal Chem 31:39
Sharifian H, Kirk DW (1986) J Electrochem Soc 133:921
Laplante F, Brossard L, Menard H (2003) Can J Chem 81:258
Laplante F, Bouchard NA, Dube P, Menard H, Brossard L (2003) Can J Chem 81:1039
Nishimura S (2001) Handbook of heterogeneous catalytic hydrogenation for organic synthesis. J. Wiley, New York, p 340
Thornber M, Woods G, Vernon C, Brown M (2000) Oxidation of bayer organic species in situ using ferrate., CHEMECA, 28th Australasian Chemical Engineering Conference, Perth, Australia, 9–12 July
Watts HL, Utley DW (1953) Anal Chem 25:864
Brisach-Wittmeyer A, Bouchard NA, Breault R, Menard H (2006) Can J Chem 84:1640
Cirtiu MC, Oudghiri Hassani H, Bouchard NA, Rowntree P, Ménard H (2006) Langmuir 22:6414
Ryan MD, Yueh A, Chen W-Y (1980) J Electrochem Soc 127:1489
Acknowledgements
We thank Alcan International Limited (Arvida Research and Development Centre), the University of Sherbrooke (Electrodes Material Science Laboratory) and the NSERC for funding and material support.
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Bouchard, NA., Brisach-Wittmeyer, A., Breault, R. et al. Selective electrochemical reactions of an alumina hydrate crystallization inhibitor. J Appl Electrochem 37, 625–630 (2007). https://doi.org/10.1007/s10800-007-9295-3
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DOI: https://doi.org/10.1007/s10800-007-9295-3