The present work aimed at the study of citric acid solvent extraction in order to establish the composition of the organic phase and to obtain thermodynamic and kinetic data for the chosen system. Discontinuous extraction experiments in a single stage were performed from a synthetic solution of citric acid, with the typical concentration (10% w/v) observed in industrial fermented musts. Exploratory experiments were carried out using different organic phases in order to select the most suitable solvent phase to further continuous extraction tests in a mechanically agitated column. The selected organic phase composition was: Alamine？ 336, ExxalTM 13 tridecyl alcohol, and the aliphatic diluent EscaidTM 110. Next, the effects of the contact time and of the concentrations of extractant and modifier on the citric acid extraction were studied. Among the investigated conditions, the best one was 10 minutes of contact time, 30% w/v of Alamine？ 336, and 10% w/v of ExxalTM 13 tridecyl alcohol. For this condition, the equilibrium isotherm (28°C ± 2°C) was determined, and the equilibrium constant was calculated (36.8 (mol·L-1)-1.5). It was considered that trioctylamine and citric acid complexation reaction occurs mainly with non-dissociated citric acid form, because the aqueous feed solutions’ pH is lower than the citric acid pKa1. It was found that 1.5 molecules of the extractant, on average, are required to react with one citric acid molecule, which can indicate that reactions with different extractant/citric acid ratios occur simultaneously. Next, the rate constants for the direct and inverse reactions, 2.10 (mol·L-1)-1.5·s-1 and 5.69 × 10-2 s-1, respectively, were calculated. Coefficients of determination (R2) values higher than 0.93 were found in these calculations, suggesting that the results obtained using a computer modeling would be very close to those results obtained experimentally. Therefore, the present work provides data required to future modelling, design, and simulation of citric acid solvent extraction processes.
References
[1]
Fani, M. (2011) ácido Cítrico ou Citrato de Hidrogênio. In: Fani, M., Ed., Aditivos e Ingredientes, Editora Insumos, São Paulo, 30-35.
http://aditivosingredientes.com.br/upload_arquivos/201604/2016040746833001460591974.pdf
[2]
Bauer, U., Marr, R., Rückl, W. and Siebenhofer, M. (1989) Reactive Extraction of Citric Acid from an Aqueous Fermentation Broth. Berichte der Bunsengesellschaft für Physikalische Chemie, 93, 980-984.
https://doi.org/10.1002/bbpc.19890930911
[3]
Sun, X., Lu, H. and Wang, J. (2017) Recovery of Citric Acid from Fermented Liquid by Bipolar Membrane Electrodialysis. Journal of Cleaner Production, 143, 250-256.
https://doi.org/10.1016/j.jclepro.2016.12.118
[4]
Luo, H., Cheng, X., Liu, G., Zhou, Y., Lu, Y., Zhang, R., Li, X. and Teng, W. (2017) Citric Acid Production Using a Biological Electrodialysis with Bipolar Membrane. Journal of Membrane Science, 523, 122-128.
https://doi.org/10.1016/j.memsci.2016.09.063
[5]
Djas, M. and Henczka, M. (2016) Reactive Extraction of Citric Acid Using Supercritical Carbon Dioxide. The Journal of Supercritical Fluids, 117, 59-63.
https://doi.org/10.1016/j.supflu.2016.05.005
[6]
Yokoya, F. (1992) Fermentaçoes Industriais 1. Fundação Tropical de Pesquisas e Tecnologia André Tosello Press, Campinas.
[7]
Pazouki, M. and Panda, T. (1998) Recovery of Citric Acid—A Review. Bioprocess Engineering, 19, 435-439. https://doi.org/10.1007/PL00009029
[8]
Bizek, V., Horácek, J., Rericha, R. and Kousova, M. (1992) Amine Extraction of Hydroxycarboxylic Acids. 1. Extraction of Citric Acid with 1-Octanol/n-Heptane Solutions of Trialkylamine. Industrial & Engineering Chemistry Research, 31, 1554-1562. https://doi.org/10.1021/ie00006a019
[9]
Konzen, C. (2013) Projeto e Montagem de uma Unidade Piloto para Operação de um Sistema de Membranas Líquidas Surfatantes Utilizando-Se uma Coluna Mecanicamente Agitada. Ph.D. Thesis, Federal University of Minas Gerais, Belo Horizonte.
[10]
Procházka, J., Heyberger, A. and Volaufová, E. (1997) Amine Extraction of Hydroxycarboxylic Acids. 3. Effect of Modifiers on Citric Acid Extraction. Industrial & Engineering Chemistry Research, 36, 2799-2807. https://doi.org/10.1021/ie9607107
[11]
Maurer, G. (2006) Modeling the Liquid-Liquid Equilibrium for the Recovery of Carboxylic Acids from Aqueous Solutions. Fluid Phase Equilibria, 241, 86-95.
https://doi.org/10.1016/j.fluid.2005.11.005
[12]
Kirsch, T. and Maurer, G. (1998) Distribution of Binary Mixtures of Citric, Acetic and Oxalic Acid between Water and Organic Solutions of Tri-N-Octylamine. Part III. Organic Solvent Chloroform. Fluid Phase Equilibria, 146, 297-313.
https://doi.org/10.1016/S0378-3812(98)00209-X
[13]
Nikhade, B.P., Moulijn, J.A. and Pangarkar, V.G. (2004) Extraction of Citric Acid from Aqueous Solutions with Alamine 336: Equilibrium and Kinetics. Journal of Chemical Technology & Biotechnology, 79, 1155-1161.
https://doi.org/10.1002/jctb.1109
[14]
Malmary, G., Albet, J., Putranto, A.M.H. and Molinier, J. (2001) Recovery of Carboxylic Acids from Aqueous Solutions by Liquid-Liquid Extraction with a Triisooctylamine Diluent System. Brazilian Journal of Chemical Engineering, 18, 441-447. https://doi.org/10.1590/S0104-66322001000400008
[15]
Bressler, E. and Braun, S. (1999) Separation Mechanisms of Citric and Itaconic Acids by Water-Immiscible Amines. Journal of Chemical Technology and Biotechnology, 74, 891-896.
https://doi.org/10.1002/(SICI)1097-4660(199909)74:9<891::AID-JCTB113>3.0.CO;2-E
[16]
Keshav, A., Norge, P. and Wasewar, K.L. (2012) Reactive Extraction of Citric Acid Using Tri-N-Octylamine in Nontoxic Natural Diluents: Part 1—Equilibrium Studies from Aqueous Solutions. Applied Biochemistry and Biotechnology, 167, 197-213. https://doi.org/10.1007/s12010-012-9682-z
[17]
Bízek, V., Horácek, J., Kousová, M., Heyberger, A. and Procházka, J. (1992) Mathematical Model of Extraction of Citric Acid with Amine. Chemical Engineering Science, 47, 1433-1440. https://doi.org/10.1016/0009-2509(92)80288-N
[18]
Vaňura, P. and Kuca, L. (1976) Extraction of Citric Acid by the Toluene Solutions of Trilaurylamine. Collection of Czechoslovak Chemical Communications, 41, 2857-2877. https://doi.org/10.1135/cccc19762857
[19]
Thakre, N., Prajapati, A.K., Mahapatra, S.P., Kumar, A., Khapre, A. and Pal, D. (2016) Modeling and Optimization of Reactive Extraction of Citric Acid. Journal of Chemical Engineering, 61, 2614-2623. https://doi.org/10.1021/acs.jced.6b00274
[20]
Jin, Y., Zou, D., Wu, S., Cao, Y. and Li, J. (2015) Extraction Kinetics of Phosphoric Acid from the Phosphoric Acid-Calcium Chloride Solution by Tri-N-Butyl Phosphate. Industrial & Engineering Chemistry Research, 54, 108-116.
https://doi.org/10.1021/ie503273j
[21]
Shlewit, H. and Alibrahim, M. (2008) Counter Current Extraction of Phosphoric Acid: Food Grade Acid Production. Periodica Polytechnica Chemical Engineering, 52, 7-9. https://doi.org/10.3311/pp.ch.2008-1.02
[22]
Schimidt, V.S. (1971) Amine Extraction. John Wiley & Sons Incorporated, New York.
[23]
Canari, R. and Eyal, A. (2004) Temperature Effect on the Extraction of Carboxylic Acids by Amine-Based Extractants. Industrial & Engineering Chemistry Research, 43, 7608-7617. https://doi.org/10.1021/ie034127j
[24]
Lima, U.A., Aquarone, E. and Borzani, W. (1975) Biotecnologia Tecnologia das Fermentaçoes. Edgard Blücher, São Paulo.
[25]
Rohr, M., Kubicek, C.P. and Kominek, J. (1983) Citric Acid. In: Reed, G., Ed., Biotecnology, Wenheim, New York, 440-442.
Poposka, F.A., Nikolovski, K. and Tomovska, R. (1998) Kinetics, Mechanism and Mathematical Modelling of Extraction of Citric Acid with Isodecanol/N-Paraffins Solutions of Trioctylamin. Chemical Engineering Science, 53, 3227-3237.
https://doi.org/10.1016/S0009-2509(98)00125-0
[28]
Montgomery, D.C. and Runger, G.C. (2010) Applied Statistics and Probability for Engineers. John Wiley & Sons, New York.
