Extraction Of Butyric Acid Research Articles

Liquid–Liquid Equilibria of Butyric Acid, Water, and Methyl Isobutyl Ketone with the Aid of Biological Buffer as a Green Auxiliary Agent

Biological buffer has a significant impact on aqueous organic phase equilibria in extraction processes. This study investigated the effect of biological buffer on the efficacy of butyric acid extraction from aqueous solution utilizing methyl isobutyl ketone (MIBK) as the extraction solvent. The liquid–liquid equilibria (LLE) of quaternary systems of methyl isobutyl ketone (MIBK) + butyric acid + water + biological buffer MOPS [3-(N)-morpholino propane sulfonic acid], HEPES (2-(4-(2-hydroxyethyl)-1-piperazinyl)ethanesulfonic acid), or EPPS (4-(2-hydroxyethyl)-1-piperazine propanesulfonic acid) were determined at temperature T = 303.15 K (30 °C) and P = 0.1 MPa (atmospheric pressure). The addition of EPPS to the butyric acid aqueous solution resulted in superior extraction efficacy compared to the other biological buffers, as determined by experimental data. Generally, the extraction performance was in the order EPPS > MOPS > HEPES, which represented the buffering-out strength as well. The non-random two-liquid (NRTL) and UNIversal QUAsi Chemical (UNIQUAC) models fit well with the actual LLE data of the quaternary systems. The σ-profile analysis was also evaluated in this study. Additionally, a potential process flow sheet using biological buffer and MIBK solvent was suggested for removing butyric acid from its aqueous solution.

Two-phase anaerobic digestion for enhanced valorisation of whiskey distillery by-products

The valorisation of whiskey by-products was assessed and compared in three anaerobic digestion systems. The systems produced similar methane yields, which could satisfy up to 44% of the thermal energy demand at a distillery. Using methane generated from by-products would displace natural gas and reduce the distillery's carbon footprint. Two-phase systems had higher methane content (ca. 75 %vol) than the traditional system (54 %vol) and furthermore, unlocked opportunities for volatile fatty acid production. The potential value that could be generated from the extraction of butyric acid and caproic acid was approximately €6.76 million for a 50 million litre alcohol facility (0.14 € per litre of whiskey). All three anaerobic digestion systems showed the potential to valorise whiskey by-products and convert current linear distillery production processes into circular repurpose and reuse production processes.

Reactive extraction of butyric acid from effluent streams and fermentation broth by using tri-n-octyl amine in decanol/natural oils

Reactive extraction of butyric acid from effluent streams and fermentation broth by using tri-n-octyl amine in decanol/natural oils

Reactive Extraction of Butyric Acid from Water Using Trioctyl Amine in 1-Decanol and Green Natural Oils

In this work, butyric acid (BA) was extracted using trioctyl amine (TOA). Various temperature-dependent (298.15–318.15 K) process parameters were estimated and analyzed. To reduce the harmful effects of TOA and to avoid the detrimental effects of toxic diluents on microorganisms, green and nontoxic diluents, sunflower and soybean oils, were tested. In physical extraction, KDdil and the partition coefficient, P, decreased in the order of 1-decanol > sunflower oil > soybean oil, whereas the dimerization constant, D, showed the opposite trend. In chemical extraction, the extraction efficiencies were 85–90% for 1-decanol, 82–88% for sunflower oil, and 75–86% for soybean oil. In terms of the distribution coefficient, 1-decanol was a better diluent than sunflower oil, followed by soybean oil. The high distribution coefficients and extraction efficiencies obtained using sunflower and soybean oils were found to be encouraging for their use in biorefinery industries. (KDchem)/(KDphy) was greater than 1.0 in all of the studied cases. The best distribution coefficient model was identified. The complexation reaction stoichiometry and the equilibrium complexation reaction constant were estimated using the differential evolution technique. The order of the complex molality, [HAmSn]org, in different diluents was 1-decanol > sunflower > soybean. Different thermodynamic parameters were determined and analyzed. Variations of acid–extractant, free acid, and dimer molalities at the chemical equilibrium state were found and discussed. Analysis based on the enthalpy change due to mass transfer, (ΔH)mass tr, indicated the easiest mixing of the phases in sunflower oil and the most difficult in soybean oil. The reaction equilibrium constant, KE(m:n), had the highest value at the lowest temperature (298.15 K) and decreased with an increase in temperature and had values in the order of 1-decanol > sunflower > soybean.

New phosphonium ionic liquid with neodecanoate anion as butyric acid extractant

Liquid–liquid equilibrium data on butyric acid (BA) extraction by new ionic liquid (IL) tetradecyl(trihexyl)phosphonium neodecanoate ([C14C6C6C6P][NDec]) are presented and correlated using a model developed earlier. Extraction performance of the new IL is comparable with that of previously tested phosphonium ILs with decanoate and phosphinate anions. High loading of IL with BA of more than 12 BA molecules per one IL ion pair was achieved at aqueous BA concentration of 1.2 mol dm−3. The overall extraction mechanism includes competitive extraction of BA and water, and coextraction of BA with water. Both these sub-mechanisms act simultaneously, the first one dominates below IL loading by acid of 2 and the second one above this value. Dynamic viscosity of water saturated [C14C6C6C6P][NDec] is slightly higher compared to a similar IL with decanoate anion [C14C6C6C6P][Dec] (104 and 96 mPa s). However, at 298 K dried [C14C6C6C6P][Dec] is solid, while [C14C6C6C6P][NDec] is liquid even below 253 K which is a great advantage. Viscosity of equilibrium organic phases shows a maximum at IL loading by BA of about 1.6 which corresponds to the minimal solute (BA + water) content and maximal molar fraction of IL due to water release from the solvent.

Butyric Acid Reactive Extraction Using Trioctylamine in 1-Decanol: Response Surface Methodology Parametric Optimization Technique

The optimization of the reactive extraction of butyric acid from an aqueous stream was effectively carried out using response surface methodology. Three process parameters were studied, viz. initial butyric acid concentration, trioctylamine concentration and temperature, to examine the interactive effects on extraction efficiency and distribution coefficient. A Box-Behnken design comprising of seventeen experimental runs was utilized in the reactive extraction study of butyric acid. Analysis of a second-order polynomial model yielded the following optimal conditions: temperature 301.829 K, initial butyric acid concentration 0.493 kmol/m3, trioctylamine composition 26.417%v/v with the following responses: distribution coefficient = 28.795 and extraction efficiency of 96.666%. Experimental validation of the model was carried out with the predicted process variables, and the responses obtained (distribution coefficient = 27.171, extraction efficiency = 96.450%) were in close conformity to the predicted outcomes. Three-dimensional surface plots obtained from statistical analysis demonstrated that the butyric acid concentration and TOA composition had a more significant and interactive effect than the temperature on the response value in the reactive extraction process.

Fermentative hydrogen production from cheese whey with in-line, concentration gradient-driven butyric acid extraction

Hydrogen (H2) generation from cheese whey with simultaneous production and extraction of volatile fatty acids (VFAs) was studied in UASB reactors at two temperatures (20 and 35 °C) and pH values (5.0 and 4.5). The extraction module, installed through a recirculation loop, was a silicone tube coil submerged in water, which allows concentration-driven extraction of undissociated VFAs. Operating conditions were selected as a compromise for the recovery of both H2 and VFAs. Batch experiments showed a higher yield (0.9 mol H2 mol−1 glucoseeq.) at 35 °C and pH 5.0, regardless of the presence of the extraction module, whereas lower yields were obtained at pH 4.5 and 20 °C (0.5 and 0.3 mol H2 mol−1 glucoseeq., respectively). VFAs crossed the silicone membrane, with a strong preference for butyric over propionic and acetic acid due to its higher hydrophobicity. Sugars, lactic acid and nutrients were retained, resulting in an extracted solution of up to 2.5 g L−1 butyric acid with more than 90% purity. Continuous experiment confirmed those results, with production rates up to 2.0 L H2 L−1 d−1 and butyric acid extraction both in-line (from the UASB recirculation) and off-line (from the UASB effluent). In-line VFA extraction can reduce the operating costs of fermentation, facilitating downstream processing for the recovery of marketable VFAs without affecting the H2 production.

Investigations on Reactive Extraction of Butyric Acid Using Tri-n-Octyl Amine in Various Biodiesels

Butyric acid is a monocarboxylic acid which can be produced economically by fermentation from green feedstock. As the recovery of butyric acid from dilute fermentation broth is a challenge and hence it needs to develop a competitive downstream recovery process. Butyric acid finds a wide range of applications in pharmaceutical, food, cosmetics and power industries. Reactive extraction is one of the most promising and accessible methods which can be used as first separation step for recovery of butyric acid from dilute wastewater stream or fermentation broth. In present study, the physical and reactive extraction of butyric acid using tri-n-octylamine (TOA) in biodiesel made from sesame oil, rice bran oil, karanja oil and sunflower oil were studied at 298K and comparatively found the reactive extraction as more efficient. The Partition coefficient P, dimerization constant D and the distribution coefficient KD were obtained in the physical extraction study. In reactive extraction, the results were obtained in terms of distribution coefficient KD, loading ratio O and the degree of extraction E%.

NMR study of structural changes of alkyl-phosphonium decanoate ionic liquid induced by water and butyric acid extraction

Ionic liquids (ILs) have received substantial attention in basic and applied research in the last two decades. This work is focused on deeper understanding of carboxylic acids extraction by ILs with potential in recovery of platform chemicals from diluted streams in biorefineries. Results of an NMR study of structural changes of a system composed of trihexyl-(tetradecyl)-phosphonium decanoate, butyric acid (BA) and water are presented. 1H, 13C and 31P NMR were used for the determination of system composition, its dynamic behavior and for the study of interactions between components of the system with different water and BA loadings. The hypothesis of water being extracted by IL in separate regions (polar domains) was postulated. Water extraction goes through a continuous series of intermediate structures until a relatively stable structure is achieved. Extraction of BA with water saturated IL proceeds via two different mechanisms: replacement of water molecules in polar domains by BA molecules in early stages of the extraction, and co-extraction of BA and water molecules at higher BA concentrations with the change of IL structure to a less rigid one. From dynamic study (selfdiffusion coefficients) it follows that components of IL systems do not form tight complexes, but water and BA molecules can move partly independently of IL ions.

Extraction of Butyric Acid by Phosphonium Decanoate Ionic Liquid

Liquid–liquid equilibrium data for butyric acid (BA) extraction by phosphonium decanoate ionic liquid (IL) were measured and modeled. An extended more general extraction mechanism taking into account differences in IL anion basicities was suggested. The overall extraction mechanism involving three submechanisms of competitive and noncompetitive extraction of BA and water coextraction was successfully applied to the system with phosphonium decanoate. Formation of (p, 1) complexes with p of up to 16 molecules of BA with 1 ion pair of IL was supposed. A 3 times lower value of the stability constant of the first IL–BA bond in decanoate compared with phosphinate ILs could result in easier regeneration of acid-loaded IL in vacuum distillation. Aggregation and micellar structures in water-saturated IL were confirmed by dynamic light scattering measurements. The concentration dependence of equilibrium solvent-phase viscosities goes through a maximum that corresponds with a minimum in the dependencies of density a...

Enhanced extraction of butyric acid under high-pressure CO2 conditions to integrate chemical catalysis for value-added chemicals and biofuels

BackgroundExtractive fermentation with the removal of carboxylic acid requires low pH conditions because acids are better partitioned into the solvent phase at low pH values. However, this requirement conflicts with the optimal near-neutral pH conditions for microbial growth.ResultsCO2 pressurization was used, instead of the addition of chemicals, to decrease pH for the extraction of butyric acid, a fermentation product of Clostridium tyrobutyricum, and butyl butyrate was selected as an extractant. CO2 pressurization (50 bar) improved the extraction efficiency of butyric acid from a solution at pH 6, yielding a distribution coefficient (D) 0.42. In situ removal of butyric acid during fermentation increased the production of butyric acid by up to 4.10 g/L h, an almost twofold increase over control without the use of an extraction process.ConclusionIn situ extraction of butyric acid using temporal CO2 pressurization may be applied to an integrated downstream catalytic process for upgrading butyric acid to value-added chemicals in an organic solvent.

Density, Viscosity, and Structure of Equilibrium Solvent Phases in Butyric Acid Extraction by Phosphonium Ionic Liquid

Density, viscosity, and dynamic light scattering (DLS) measurements have been done for quaternary phases with phosphonium ionic liquid (Cyphos IL-104 + dodecane + BA + water) from the extraction of butyric acid (BA) by a binary solvent (IL + dodecane). Density data show volume contraction in the solvent. Addition of water, BA, or dodecane considerably decreases IL viscosity, while BA decreases viscosity less than water. When increasing BA concentration, viscosity of the solvent phase in equilibrium without dodecane goes through a maximum at BA mass fraction of about 0.2. In solvents with more than 30% in mass fraction of dodecane, almost no influence of BA on viscosity was observed. Viscosity of water saturated solvents with IL concentration below 50% in mass fraction is markedly higher than in solvents containing also BA. This is due to the formation of dodecane-rich micelles in water saturated solvents which increase IL concentration in the bulk of the solvent. No large aggregates with size above 100 nm...

New Mechanism and Model of Butyric Acid Extraction by Phosphonium Ionic Liquid

A new model of the liquid/liquid equilibrium of butyric acid (BA) and water extraction from aqueous solutions to an organic solvent containing phosphonium ionic liquid and dodecane has been derived. It has seven fitting parameters and describes experimental data well. Reactive extraction with formation of the (p, 1) acid-IL complexes with p ≤ 11 acids on one hand and their aggregation by water bridges on the other hand refer to the dualistic character of the extraction process and the developed model. The values of two equilibrium constants characterizing the stability of hydrogen bonds between acid and IL anion are 3 and 2 orders of magnitude larger as compared with constants characterizing stability of acid–acid H-bonds. Water is extracted via two reactive mechanisms. The first is a competitive extraction of acid and water which results in the release of water from the solvent as the BA extraction proceeds. The second mechanism is coextraction of water with BA. At the acid loading of IL above 3, this me...

Study on extraction and separation of butyric acid from clostridium tyrobutyricum fermentation broth in PEG/Na2SO4 aqueous two-phase system

A PEG/Na2SO4 aqueous two-phase system (ATPS) was used for the extraction of butyric acid from a fermentation broth. Sodium sulfate was employed to precipitate the residual carbohydrate and nitrogen compounds, and then the filtrate from filtration was added into PEG to form two aqueous phases. By using response surface methodology (RSM), a study was made of the effects of PEG molecular weight and concentration, sodium sulfate concentration, temperature, pH on the extraction yield of butyric acid, to optimize the experimental conditions for the extraction. The study results showed that the optimal conditions for the extraction using PEG and Na2SO4 ATPS were 26% PEG 6000 (w/w), 9.6% Na2SO4 (w/w), 36°C and pH 3.0, under which the yield of butyric acid was up to 91.74±0.46%, and the value was raised by about 3.7% through a two-stage extraction. Acetic acid was removed by distillation from the resultant mixed acids so that a relatively pure butyric acid was obtained. The present study proved it is feasible to extract and purify butyric acid from a fermentation broth by adopting the ATPS consisting of PEG and Na2SO4.

Separation of butyric acid in fixed bed column with solvent impregnated resin containing ammonium ionic liquid

Batch equilibrium and fixed bed column extraction experiments for the extraction of butyric acid (BA) into solvent impregnated resin (SIR) have been done. Microporous Amberlite XAD-1180N was impregnated with an ammonium ionic liquid (IL) trialkylmethylammonium bis(2,4,4-trimethylpentyl)phosphinate. The BA extraction capacity isotherm has not a Langmuir type shape and no finite capacity was observed. The loading of the impregnated IL with the extracted BA at 37°C is in agreement with the loading from L/L extraction equilibrium of BA at 25°C. Capacity of freshly prepared SIR particles is superior to classical porous ion-exchangers. Both the temperature and the superficial velocity in column influence the shape of the breakthrough-curve in fixed bed extraction of BA using SIR. Sharpening of the breakthrough curve was observed with the increasing temperature and decreasing superficial velocity. Stripping with water is not efficient for the regeneration of the loaded column after extraction because of low concentration of the product acid in the obtained effluent. Higher BA concentration was achieved by stripping with 0.15kmolm−3 and 0.075kmolm−3 NaOH solutions. The combination of initial water stripping coupled with consecutive stripping by alkali can be beneficial for decreasing the consumption of chemicals and further processing of the product. After two extraction/stripping cycles, a stable capacity was achieved and sustained for 14cycles, showing the possibility of long-term application of the prepared SIR in real technology.

Modeling extraction equilibria of butyric acid distributed between water and tri-n-butyl amine/diluent or tri-n-butyl phosphate/diluent system: Extension of the LSER approach

Extraction of butyric acid from water by tri-n-butyl amine and tri-n-butyl phosphate dissolved in oxygenated polar diluents of proton-donating and proton-accepting types (1-octanol, acetophenone, ethyl butyrate, ethyl pentanoate, ethyl nonanoate, diethyl malonate), as well as a comparison with extraction equilibria of pure diluent alone have been studied at 298K. Among the tested diluents, 1-octanol alone yields the highest extraction efficiency. The strength of complex formation is larger for tri-n-butyl amine as compared to tri-n-butyl phosphate both favoring mainly the formation of acid1–extractant1 structure. Ethyl butyrate promotes more readily the solvation of the formed organic phase complexes.The distribution data have been subjected to formulation of multivariable correlations depending on LSER (linear solvation energy relation) and mass action law principles. LSER-based solvation model involving five physical descriptors is able to simulate satisfactorily distribution properties of butyric acid yielding 1.7% mean error and satisfies established limiting behavior of the physical event. The mass action law chemodel, comprising the formation of one or two acid–extractant complexes proved to be slightly less accurate yielding 4.5% mean error. The modified Langmuir model is quite accurate in reproducing the observed properties with 1.5% mean error.

Extraction of butyric acid with a solvent containing ammonium ionic liquid

A new ammonium ionic liquid (IL), trialkylmethylammonium bis-(2,4,4-trimethylpentyl)phosphinate, has been synthesized from its precursors Aliquat 336 and Cyanex 272 by the metathesis reaction. Saturated water content in this hydrophobic IL and its 0.724kmolm−3 solution in dodecane is as high as 22.4 and 13.9 mass%, respectively. This points to the presence of water-IL clusters and reverse micelles at lower IL concentrations identified by DLS measurements. Equilibrium data in the extraction of butyric acid (BA) into this IL and its 0.724kmolm−3 solution in dodecane are presented. Experimental results have shown that the new ammonium IL is a good extractant of BA, with the distribution coefficient of over 80 at low BA concentrations in aqueous phase. The loading of the IL with extracted BA in experiments ranges up to 7, suggesting that IL forms complexes with multiple molecules of BA in chain. Water content in the organic phase initially sharply decreases with the increasing concentration of the extracted BA due to the water clusters and reverse micelles breakage. Dry IL is practically a non-flowing gel but when saturated with water or BA and/or mixed with dodecane, its viscosity decreases by more than two orders of magnitude. Thermogravimetric analysis has shown thermal stability of this IL at temperatures of up to 150°C.

Simulation of a new regeneration process of solvents with ionic liquid by short-path distillation

A new promising process for the regeneration of solvents with ionic liquid (IL) by short-path distillation (SPD) has been proposed and its application potential analyzed by simulation. Main advantage of this process compared to classical stripping with alkali solution is that the product is in form of free acid, not its salt and the consumption of chemicals is reduced. The model loaded solvent with phosphonium IL from membrane based solvent extraction (MBSE) of butyric acid (BA) was regenerated by two stage SPD at the temperature of 130 and 160°C and pressure of 13 and 2kPa, respectively. SPD was combined with extraction of BA from the dodecane phase of distillates by water. Yield of BA in distillates was 89%. The concentration factors of BA in both concentrates compared to BA concentration in the fermentation broth were of 25 and 43, respectively, for the dodecane content in the dry solvent containing 70 mass% of IL. Overall theoretical heat consumption in SPD was 3410kJperkg of recovered BA. The simulation has shown that both the yield of BA in MBSE and the mass flux of the solvent in MBSE are strongly influenced by the residual content of BA in recycled dodecane after the extraction of BA. Both parameters play a key role in the process performance. Additional experimental data on MBSE, SPD and dodecane extraction are needed for design and optimization of the hybrid process.

Simulation of a hybrid process involving extraction into ionic liquid impregnated microparticles and microfiltration

A new hybrid process involving the extraction of butyric acid (BA) into ionic liquid impregnated microparticles and the microfiltration (extraction-microfiltration, EMF) process has been proposed and its feasibility examined by simulation. Diafiltration of the regenerated suspension of the solvent impregnated resin (SIR) with water is important to decrease the amount of BA in the recycled regenerated suspension, BA concentration in the lean fermentation broth, consumption of chemicals and to increase the yield of the BA in concentrates. Improvement of these parameters is significant (decrease of chemicals’ consumption and BA concentration in the lean fermentation broth by over 80% and increase of the BA yield from 56 to 91% for a three stage EMF process) for diafiltration with the volumetric flowrate of washing water being twice the volumetric flowrate of the diafiltered suspension. Above this ratio, the gain in the BA yield and consumption of chemicals is not high. At the same time, concentration factor ...

Extraction of butyric acid by a solvent impregnated resin containing ionic liquid

Equilibrium and kinetics of extraction of butyric acid (BA) into solvent impregnated resins (SIRs) have been studied. Microporous Amberlite XAD-1180N was impregnated with a new ammonium ionic liquid (IL) trialkylmethylammonium-bis(2,4,4-trimethylpentyl)phosphinate or with its solution in dodecane. No difference in BA extraction equilibrium between the free organic phases and the same phase impregnated in SIRs has been observed. This shows that the polymer matrix of the resin has no significant impact on extraction properties of impregnated IL. SIR impregnated with IL solution in dodecane exhibit faster extraction kinetics with lower saturation times compared to SIR with pure IL, what can be attributed to lower viscosity of the solvent with diluent. The kinetics of extraction into used SIRs with a mean particle diameter of about 660 μm was fast and 95% of their equilibrium saturation was achieved in less than 350 s which is one order of magnitude faster than achieved in adsorption into resins. The value of the effective diffusion coefficient in extraction is larger than in stripping, suggesting that kinetics of the stripping is influenced by the slower decomposition of the complex of BA with IL.