Treatment of Effluents Issued from Agro-Food Industries by Liquid–Liquid Extraction of Malic and Lactic Acids Using Tri-n-octylamine and Tri-n-butyl Phosphate (original) (raw)
Related papers
Journal of Chemical & Engineering Data, 1994
Separation of an organic solute from dilute aqueous solution is difficult when the solute is not sufficiently volatile for distillation and furthermore is very soluble in the water phase. In this case, it is economically preferable to remove the solute by solvent extraction. In this work, the possibility of the extraction of lactic acid from agroindustrial aqueous effluent was studied. Two type of organic solvents such as organophosphorus extractant and a long-chain tertiary amine dissolved in various diluents of varying polarity were chosen for their abilities to extract lactic acid. Owing to their very low solubilities in the aqueous phase which limit the environmental pollution, the use of these solvents in biotechnology and food processing was reported in previous works (
Biochemical Engineering Journal, 2004
The paper deals with the lactic acid extraction by tri-n-octylamine dissolved in decanol and docecane. The extraction efficiency depends on the initial lactic acid concentration and the initial pH value of the solution. In case of lactic acid extraction from simulated fermentation broth, the partially loading of extractant with HCl leads to increasing of the distribution coefficient. The extraction equilibrium constants have been determined. The strong influence of diluents on the values of the graphically determined extraction constant and the number of extractant molecules in the acid-amine complex has been shown. A mathematical model of extraction, taking into account formation of (1:1) (2:1) and (1:2) acid/amine complexes, has been composed and solved. The model fits very well the experimental results.
Lactic acid is an important chemical product with wide use in many industrial fields. About a half of world production of lactic acid is made by fermentation of different sugars by means of Lactobacillus sp. strains. Two methods for overcoming the problems, arising from the difference in pH optima for extraction and fermentation in the extractive lactic acid fermentation, are proposed. The first method is based on the use of a mixed extractant composed by tri-n-octylamine (TOA) and Aliquat 336 (methyltrioctylammomium chloride), dissolved in decanol and dodecane. The use of mixed extractant leads to increase in extraction performance in comparison with individual extractants. The extraction efficiency depends on initial acid concentration, pH and Aliquat/TOA ratio as well. While at 5 gl -1 lactic acid the distribution coefficient increase with increasing of Aliquat concentration, for 10 and 25 gl -1 lactic acid the value of distribution coefficient passes through maximum. With increase of acid concentration the position of the maximum shifts to higher TOA concentration. The second method includes the use of tri-n-octylamine (TOA) partially converted to amine hydrochloride. This approach leads to increase in the extraction performance in comparison to the extraction with TOA at high pH values. The extraction efficiency depends on initial lactic acid concentration, pH value, and degree of loading with HCl.
2017
This study evaluated the optimum condition of solvent recovery by evaporation method for the liquid-liquid extraction of lactic acid. The aspects observed in this study include the separation coefficient and the concentration of lactic acid obtained as the product of evaporation. Independent variables used are variations of temperature (110, 120 and 130 oC), and operating pressure (20, 30, and 40 mbar). Analyzes have been performed by using volume balance and characterization test using HPLC method. The result of this study indicate that the decrease of operating pressure, as well as temperature rises, can increase the performance of evaporation. However, at temperature above 120 oC, degradation of lactic acid happened, so that the amount of TBA that evaporated is lower. The optimum operating conditions at TBA recovery process is at temperature of 120 oC and pressure at 20 mbar with distribution coefficient 0.78. Lactic acid concentration that obtained at the optimum conditions is 7...
Reactive extraction of lactic acid with Trioctylamine/Octanol/n-Undecane
2017
The trioctylamine (TOA)/methylene chloride (MC)ln-hexane system was used as the extraction agent for the extraction of lactic acid. Curves of equilibrium and hydration were obtained at various temperatures and concentrations of TOA. A modified mass action model was proposed to interpret the equilibrium and the hydration curves. The reaction mechanism and the corresponding parameters which best represent the equilibrium data were estimated, and the concentration of water in the organic phase was predicted by inserting the parameters into the simple mathematical equation of the modified model. The concentration of MC and the change of temperature were important factors for the extraction and the stripping process. The stripping was performed by a simple distillation which was a combination of temperature-swing regeneration and diluent-swing regeneration. The type of inactive diluent has no influence on the stripping. The stripping eficiencies were about 70%.
Effect of inorganic salts on liquid-liquid equilibrium in extraction of lactic acid using 1-butanol
2013
This thesis aims to study effect of inorganic salts on liquid-liquid equilibrium (LLE) of water, 1-butanol and lactic acid, and its application in extraction of the acid from aqueous solution using 1-butanol. There are three parts of study in this thesis. The first part is a study of liquid-liquid equilibrium of electrolyte mixture system containing water, 1-butanol, and different inorganic salt i.e., NaCl, Na 2 SO 4 , NH 4 Cl and ((NH 4) 2 SO 4 at temperatures in range of 303.15 to 323.15 K under atmospheric pressure. Experimental results showed that solubility between water and 1-butanol decreased with increasing inorganic salt concentration and the temperature in the range studied here was found to have a minor effect on this system. Correlation of experimental data by modified extended UNIQUAC model gave a satisfactory agreement, with an average absolute root mean square deviation of less than 1%. The second part studied liquid-liquid equilibrium of water, 1-butanol and lactic acid system under atmospheric pressure at 303.15 K. Possibility of lactic acid extraction using 1-butanol was evaluated from distribution coefficient of the acid between aqueous and organic phases. The results showed that the distribution coefficient and degree of lactic acid extraction increased with increasing lactic acid IV concentration in the starting solution. The correlation of experimental LLE data was determined by UNIQUAC and NRTL models. It was found that the UNIQUAC model was more consistent with experimental LLE data, with an average absolute root mean square deviation less than 0.5%. In the final part, the inorganic salt-modified LLE behavior of binary water and 1-butanol mixture was applied in the extraction of lactic acid. The results showed that each salts have a significant effect on the distribution of lactic acid between aqueous and organic phases. Upon addition of NaCl and NH 4 Cl, the distribution coefficient and degree of lactic acid extraction were decreased with increasing salt concentration. This effect is called salting in. Addition of Na 2 SO 4 and (NH 4) 2 SO 4 , on the other hand, led to increasing of the distribution coefficient and degree of lactic acid extraction. This effect is called salting out. Ability of these salts in increasing the distribution coefficient of lactic acid can be arranged as Na 2 SO 4 > (NH 4) 2 SO 4 > NaCl > NH 4 Cl. All results from this thesis lead to the conclusion that the four inorganic salts could liquid-liquid equilibrium of water, 1-butanol and water, 1-butanol, lactic acid. Na 2 SO 4 and (NH 4) 2 SO 4 could increase of efficiency of lactic acid extraction from water using 1-butanol, while NaCl and NH 4 Cl could decrease the efficiency of this process.
ChemEngineering, 2019
The present work develops the basics for the isolation of lactic acid, acetic acid and formic acid from a single as well as a mixed feed stream, as is present, for example, in fermentation broth for lactic acid production. Modelling of the phase equilibria data is performed using the law of mass action and shows that the acids are extracted according to their pka value, where formic acid is preferably extracted in comparison to lactic and acetic acid. Back-extraction was performed by 1 M NaHCO3 solution and shows the same tendency regarding the pka value. Based on lactic acid, the solvent phase composition, consisting of tri-n-octylamine/1-octanol/n-undecane, was optimized in terms of the distribution coefficient. The data clearly indicate that, compared to physical extraction, mass transfer can be massively enhanced by reactive extraction. With increasing tri-n-octylamine and 1-octanol concentration, the equilibrium constant increases. However, even when mass transfer increases, tr...
2019
This thesis aims to study a combined process of counter-current extraction and reactive distillation for recovery and purification of lactic acid from fermentation broth. Research work in the thesis is divided into four parts. The first part is the study of extraction of lactic acid with 1-butanol at room temperature using counter-current packed liquid-liquid extraction column. Sauter mean drop diameter (d32) was used to evaluate the mean dop size in the extraction and correlation of d32 was investigated. The results showed that d32 decreased with increasing dispersed phase flow rate (Qd) and decreasing nozzle diameter (DN), resulting in increasing dispersed phase mass transfer coefficient. An increase in continuous phase flow rate (Qc) affected increasing drop size, due to the coalescence of drops, resulting in reducing dispersed phase mass transfer coefficient. The second part is the synthesis and use of aluminum alginate as a solid catalyst for esterification of lactic acid with 1-butanol. Characteristics of the prepared catalyst were studied. It was found that aluminum alginate has low crystallinity, wrinkle surface and likely create strong Lewis acid sites for esterification. However, it was found that the prepared catalyst was of low thermal stability. Catalytic activity of aluminum alginate in esterification of lactic acid was investigated and found to be higher than the IV commercial catalyst, Amberlyst-15, under the same reaction conditions. In addition, it was observed that Langmuir-Hinshelwood model was able to describe the kinetic model of this reaction with small value of mean relative deviation (MRD). The third part of this thesis studied esterification of lactic acid with 1-butanol using aluminum alginate and hydrolysis of n-butyl lactate into lactic acid using Amberlyst-15 as solid catalyst in a semi-batch reactive distillation column. The results showed that lactic acid conversion and yield of n-butyl lactate of esterification increased with increasing reflux ratio. Catalyst loading did not have significant effect on value of both parameters while increasing the feed flow rate affects decreasing conversion and yield. For the hydrolysis of n-butyl lactate, the conversion and yield were found to increased with increasing catalyst loading while effect of feed flow rate and reflux ratio was similar to that in esterification. In addition, it was found that the purity of lactic acid decreased with increasing pressure, feed flow rate and reflux ratio. In the final part, experimental data from the previous part were use to design the combined counter-current extraction and reactive distillation. The process was simulated and economically evaluated using Aspen HYSYS V10 and Aspen Process Economic Analyzer. Efficiency of two process operations with no-recovery (Process A) and recovery (Precess B) of 1-butanol was studied and compared at annual capacity of 10,000 tons/year with purity of 99.99%w/w lactic acid. The results showed that the overall recovery of lactic acid obtained from Process A and B equals to 91.19 and 96.57% with production cost at 1.67 and 0.90 USD/kg of lactic acid, respectively.
In situ reactive extraction of lactic acid from fermentation media
Journal of Chemical Technology & Biotechnology, 2001
Extractive lactic acid fermentation was investigated in the presence of sun¯ower oil and Alamine-336 (with oleyl alcohol as the diluent solvent). Lactic acid was produced in various media at 37°C using Lactobacillus delbrueckii . First, the effects of oleyl alcohol (33.3%, v/v), immobilisation, and immobilisation in the presence of sun¯ower oil (5, 10, 15%, v/v) on lactic acid production were investigated. It was found that oleyl alcohol did not affect production while addition of sun¯ower oil increased lactic acid production from 10.22 to 16.46 gdm À3 . On the other hand, a toxic effect was observed for oleyl alcohol solutions containing 15±50% (v/v) Alamine-336. A maximum total lactic acid concentration of 25.59 gdm À3 was obtained when an oleyl alcohol solution containing 15% (v/v) Alamine together with immobilised cells with 15% (v/v) sun¯ower oil was used. This value was about 2.5 times that obtained from fermentation without organic solutions.
Effects of Organic Phase, Fermentation Media, and Operating Conditions on Lactic Acid Extraction
Lactic acid has extensive uses in the food, pharmaceutical, cosmetic and chemical industry. Lately, its use in producing biodegradable polymeric materials (polylactate) makes the production of lactic acid from fermentation broths very important. The major part of the production cost accounts for the cost of separation from very dilute reaction media where productivity is low as a result of the inhibitory nature of lactic acid. The current method of extraction/separation is both expensive and unsustainable. Therefore, there is great scope for development of alternative technology that will offer efficiency, economic, and environmental benefits. One of the promising technologies for recovery of lactic acid from fermentation broth is reactive liquid-liquid extraction. In this paper the extraction and recovery of lactic acid based on reactive processes is examined and the performance of a hydrophobic microporous hollow-fiber membrane module (HFMM) is evaluated. First, equilibrium experiments were conducted using organic solutions consisting of Aliquat 336/trioctylamine (as a carrier) and tri-butyl phosphate (TBP)/sunflower oil (as a solvent) The values of the distribution coefficient were obtained as a function of feed pH, composition of the organic phase (ratio of carrier to solvent), and temperature (range 8-40 °C). The optimum extraction was obtained with the organic phase consisting of a mixture of 15 wt % tri-octylamine (TOA) and 15% Aliquat 336 and 70% solvent. The organic phase with TBP performed best but is less suitable because of its damaging properties (toxicity and environmental impact) and cost. Sunflower oil, which performed moderately, can be regarded as a better option as it has many desirable characteristics (nontoxic, environment-and operator-friendly) and it costs much less. The percentage extraction was approximately 33% at pH 6 and at room temperature (can be enhanced by operating at higher temperatures) at a feed flow rate of 15-20 L/h. These results suggest that the hollow-fiber membrane process yields good percentage extraction at the fermentation conditions and its in situ application could improve the process productivity by suppressing the inhibitory effect of lactic acid.