Water Co-extraction Research Articles

Catalyst-free synthesis of 5-hydroxymethylfurfural from fructose by extractive reaction in supercritical CO2 – subcritical H2O two-phase system

An extractive reaction configuration using supercritical carbon dioxide (scCO2) as the extracting solvent was tested for the production of 5-hydroxymethyl furfural (HMF) from a 5 wt% fructose aqueous feed. In this configuration, extraction of HMF by scCO2 prevents HMF degradation in the aqueous phase. Because of water co-extraction by scCO2, the volume of the reactional mixture was maintained by continuous injection of water. Reaction was operated in a 90 mL high pressure reactor, where an HMF maximum yield of 62.4 % was achieved at 160 °C and 25 MPa, with a CO2 flow rate of 20 g.min−1 for 420 min. This is the first time that HMF is reportedly produced with such a yield by a catalyst-and organic solvent-free process. Besides, the separation efficiency reached 97.3 % and the relative purity of HMF in the extract was 95.8 wt%. Therefore, this configuration avoids post reactional purification which is needed in conventional batch processes or in extractive reaction processes using organic solvents. Based on kinetic and thermodynamic studies, modeling of the extractive reaction process was developed to perform a sensitivity analysis for CO2 flow rate and extraction efficiency, upon the HMF yield. As an example, it was shown that for 800 min reaction duration, a CO2 flow rate of 100 g.min−1 or an extraction efficiency increase by a 10-fold factor could theoretically led to HMF yields of 73.0 % and 73.7 %, respectively.

Reactive extraction: a promising approach to separate protocatechuic acid.

3,4-Dihydroxybenzoic acid, commonly known as protocatechuic acid, is a naturally occurring phenolic compound, being the active component of many medicinal and edible plants. The in vitro and in vivo studies of protocatechuic acid conclude that it possesses many pharmacological properties. Protocatechuic acid, present in waste streams of food processing industries, is considered a phenolic pollutant. Owing to its bactericidal properties and in order to maintain the standards of disposal, its removal from the waste streams is necessary. Protocatechuic acid finds applications also in bioplastics, polymers, and also bio-based active films to improve food preservation. Its direct extraction from plant secondary metabolites possesses many difficulties. Recently reports of protocatechuic acid production by several Bacillus species are present in literature. For the retrieval/removal of protocatechuic acid from aqueous streams, methods like adsorption, O3/UV or H2O2/UV, and microbial degradation are in practice. For the retrieval of carboxylic acid from fermentation broths and aqueous streams, reactive extraction by the use of specific extractants has been found to be a most suitable method owing to its several advantages. The present paper is focused on the separation of protocatechuic acid by reactive extraction as a promising approach. The parameters needed for the design such as distribution coefficient, water co-extraction, physical and chemical extraction, effect of initial acid concentration, diluents, extractant, and extractant concentration have been discussed.

Explore the competency of natural diluents with Tri-n-octylamine for the extractive separation of malonic acid

Abstract Since last 50 years, the malonic acid is produced from petroleum feedstock while recently a patent is filed by Lygos, Inc., a lab in Berkeley, California to produce malonic acid through genetically natural yeast cells by biological fermentation. Like all fermentation process the proposed method is both environment and economically friendly. The study is explore the reactive extraction of malonic acid from aqueous phase with nontoxic natural diluents for instance sunflower oil, rice bran oil, sesame oil and tri-n-octylamine as an extractant in view of novel finding in fermentation technology. The physical extraction (extraction with diluents) failed to extract any acid from aqueous solution so the extracting power depends only on extractant. The results are tabulated in terms of distribution coefficient, δ (9.633–34.436 for sunflower oil, 12.089–33.014 for sesame oil, and 11.151–37.655 for rice bran oil), loading factor, φ (0.280–4.067 for sunflower oil, 0.280–4.086 for sesame oil, and 0.280–4.123 for rice bran oil) and extraction efficiency, ƞ (90.595–97.178% for sunflower oil, 92.360–97.060% for sesame oil, and 91.770–97.413% for rice bran oil). Further overall equilibrium constant values, ɛ are in the range of 0.213–0.670 L/mol for sunflower oil, 0.208–0.671 L/mol for sesame oil, and 0.212–0.673 L/mol for rice bran oil for 0.23–0.69 mol/L of TOA. The results show that up-to 30% TOA in nontoxic diluents is suitable for the reactive extraction of malonic acid. Further, water co-extraction phenomenon also discussed and found that water co-extraction was observed more for rice bran oil.

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...

Effect of Temperature on Reactive Extraction of Gallic Acid Using Tri-n-butyl Phosphate, Tri-n-octylamine and Aliquat 336

The present work is focused on the effect of temperature on extraction of gallic acid using Aliquat 336, tri-n-butyl phosphate and tri-n-octylamine in hexanol and octanol. Distribution coefficient, loading ratio, percent extraction, equilibrium complexation constant, water coextraction, enthalpy, and entropy change were evaluated for various acid–extractant–diluent combinations with varying temperature. The extraction of GA was found to be highly exothermic at lower molality of TBP in octanol with evaluated enthalpy change as −28 743 J/mol. The extraction of gallic acid process was favored at low temperature as the process was evaluated as an exothermic in nature. Maximum extraction efficiency of 97.3% was observed at higher molality of Aliquat 336 in hexanol at lower temperature.

Reactive extraction of sodium hydroxide from alkali solutions for the separation of sodium and aluminum—Part II. Effect of diluent

Enhancing the precipitation of Al(OH)3 from supersaturated sodium aluminate solution has been a challenge for the alumina industry for decades in its effort to increase the productivity. However, limited by the thermodynamic equilibrium of alumina solubility in caustic solutions, the processes that are available to date for promoting the precipitation of Al(OH)3 are unsatisfactory. An acid–base reactive solvent extraction method is proposed to enhance the separation of sodium hydroxide from sodium aluminate mother liquor by creating a condition for re-precipitation. The extraction process has been reported in Part I of this study by the present authors. In this paper the effects of diluents on sodium extraction when using 2-tert-butyl-4-methylphenol as the main organic extractant were systematically investigated. According to the classification of diluents, the capabilities for extracting sodium in different types of diluents were compared, and the protonic polar diluents were identified as being the most effective diluent. In the absence of alkyl phenol organic extractant, the sodium extraction equilibrium in 1-octanol and 2-ethyl hexanol, and the co-extraction of water in each of them were compared. In the presence of alkyl phenol, the extraction capabilities for sodium in different C8 alcohols, including 1-octanol, 2-ethyl hexanol and 2-octanol, were compared and analyzed. The results showed that 1-octanol is the most effective diluent among the three that are studied in this project. Furthermore, inert diluents including kerosene, octane and heptane, were used to dilute the pure 1-octanol solvent in different proportions in order to decrease the viscosity of the organic phase. The effects of the inert diluent on sodium extraction and water co-extraction were studied. Finally, the particle size distributions in the equilibrated organic phases and the Margules ternary 2-suffix equations were introduced to discuss the mechanisms of sodium extraction by 1-octanol and 2-ethyl hexanol. The results of this systematic research are expected to provide valuable guidance for the selection of diluents.

Reactive Extraction of Phenylacetic Acid with Tri-n-butyl Phosphate in Benzene, Hexanol, and Rice Bran Oil at 298 K

Phenylacetic acid extraction from an aqueous system gets consideration because of its extensive uses in the production of β-lactam antibiotics. In the present paper, reactive extraction has been investigated for the removal of phenylacetic acid by tri-n-butyl phosphate from the aqueous phase in benzene, hexanol, and rice bran oil as diluents. Reactive extraction data were discussed in terms of overall distribution coefficients (Do), loading ratio (ϕ), degree of extraction (η %), and equilibrium complexation constants (Eαβ). The mass action law model was used to represent equilibrium of reactive extraction of phenylacetic acid–tri-n-butyl phosphate. Also the results on water coextraction have been presented. A further extensive discussion on toxicity, back extraction, and regeneration was given. It is a first kind of study for the removal of phenylacetic acid from the aqueous phase by reactive extraction using tri-n-butyl phosphate in benzene, hexanol, and rice bran oil.

Reactive Extraction: An Intensifying Approach for Carboxylic Acid Separation

Since last few decades, there has been a revitalization of attention towards new energy-efficient fermentation technology for large production of fermentation chemicals due to sharp increase in petroleum costs. Carboxylic acid has wide applications in various chemical, food, and pharmaceutical industries. A growing demand for biodegradable polymers, substitutes for both conventional plastic materials and new materials of specific uses such as controlled drug delivery or artificial prostheses, draws attention the need for improvement of conventional processes for carboxylic acids production. Reactive extraction is a multifunctional reactor having reaction and extraction in a single unit. This intensified approach has the closed loop process with sustainability. In present paper, the concept of reactive extraction and effect of various parameters were discussed. These studies are very useful in the view of complete design of a reactive extraction process for the carboxylic acid production. (14),(15), phenyl acetic acid (16), propionic acid (17)-(35), benzoic acid (36), pyridine-3-carboxylic acid (36), levulinic (37), butyric acid (27), (38), glycolic acid (40), itaconic acid (40), gluconic acid (41), etc. Also few reviews are available (42)-(45). In present paper various aspects for the development of reactive extraction process for the recovery of carboxylic acids has been discussed. Physical equilibrium, chemical equilibrium, extraction kinetics, effect of temperature, effect of substrate, effect of salts, effect of pH, back extraction equilibrium and kinetics, regeneration, toxicity, water co-extraction, economical has been analyzed and presented. This paper will be very useful in the context of design of intensifying process for the recovery of carboxylic acid by reactive extraction. The design window of the reactive extraction is shown in Fig. 1.

Recovery of propionic acid from aqueous phase by reactive extraction using quarternary amine (Aliquat 336) in various diluents

Propionic acid is an important carboxylic acid widely used in chemical, pharmaceutical, food and other industries. The growing importance of biological production (fermentation) expressed with new routes and increasing production rates, leads to look for technologies of downstream processing for product separation. Reactive extraction with specific extractant has been the promising technique for propionic acid recovery from fermentation broth. In present work, the extraction of propionic acid with Aliquat 336 (tri-(C 8C 10) methyl ammonium chloride) dissolved in n-heptane, petroleum ether, 1-decanol and 1-octanol respectively was investigated for various concentrations of acid. The overall distribution coefficient ( K D), loading ratios, and equilibrium complexation constants were evaluated. The comparison with pure diluent at 305 K was also made and chemical extraction was found to be better than physical extraction. Alcohols (1-octanol and 1-decanol) when used as diluents with Aliquat 336, were found to give higher K D values and also prevents the third phase formation which was found when Aliquat 336 was used with n-heptane and petroleum ether. Also the water co-extraction and back extraction/regeneration methods were discussed. The data obtained is useful in the designing of reactive extraction process for the recovery of propionic acid.

Recovery of propionic acid by reactive extraction - 1. Equilibrium, effect of pH and temperature, water coextraction

Reactive extraction is a prominent technique for recovery of carboxylic acids for dilute aqueous stream and fermentation broth. In the present paper, the effect of acid concentration, extractant concentration and type of diluent on extraction of propionic acid using tri-n-butyl phosphate (TBP) in methyl isobutyl ketone and 1-decanol was studied. Physical and chemical extraction experiments were conducted to study the influence of TBP in the respective diluents. TBP + MIBK was found to be an effective system with more than 25% improvement in extraction in comparison to TBP + 1-decanol, where no significant effect was obtained. The difference in solvation of TBP:acid complexes in respective diluents was explained in terms of physical properties of the diluents. Effect of pH, temperature and water coextraction was also studied using TBP in MIBK. Higher acid extraction was found when solution pH was lower than 4. The effect of temperature was not so predominant at the ranges studied (305-333 K). This suggests...

Impact of coffee consumption on the gut microbiota: A human volunteer study

The impact of a moderate consumption of an instant coffee on the general composition of the human intestinal bacterial population was assessed in this study. Sixteen (16) healthy adult volunteers consumed a daily dose of 3 cups of coffee during 3 weeks. Faecal samples were collected before and after the consumption of coffee, and the impact of the ingestion of the product on the intestinal bacteria as well as the quantification of specific bacterial groups was assessed using nucleic acid-based methods. Although faecal profiles of the dominant microbiota were not significantly affected after the consumption of the coffee (Dice's similarity index = 92%, n = 16), the population of Bifidobacterium spp. increased after the 3-week test period ( P = 0.02). Moreover, in some subjects, there was a specific increase in the metabolic activity of Bifidobacterium spp. Our results show that the consumption of the coffee preparation resulting from water co-extraction of green and roasted coffee beans produce an increase in the metabolic activity and/or numbers of the Bifidobacterium spp. population, a bacterial group of reputed beneficial effects, without major impact on the dominant microbiota.

Removal of Reaction Solvent by Extractive Workup: Survey of Water and Solvent Co-extraction in Various Systems

In some chemical processes, extractive workup is used to remove the solvent of reaction in an aqueous layer and to isolate the product in the organic layer. Most of the time some reaction solvent is co-extracted in the organic layer, along with some water. This has a non-negligible impact on subsequent operations (washing, crystallization), and we have thus determined those levels for ten reaction solvents and five extraction solvents in order to help the process chemist in the development of efficient isolation procedures.

Reactive extraction of d, l-α-phenylglycine with a quaternary ammonium salt: Effect of hydroxide anions and water coextraction

The extraction equilibria of α-phenylglycine in alkaline solutions with tri- n-octylmethylammonium chloride (TOMAC) (10%, v/v) in 1-decanol as diluent have been studied. Hydroxide anion and water co-extraction were also investigated. Equilibrium constants for the extraction of phenylglycine and OH - ions have been determined experimentally at 20 °C, being K ePhg = 1.09 and K eOH = 0.30. A mathematical model has been developed to predict the equilibrium concentrations from initial conditions, the equilibrium constants and mass balances to the system. The model takes into account the coextraction of water (3.5 ± 0.4%, v/v) that was determined to be independent of feed concentration.

Selectivity between Lactic Acid and Glucose during Recovery of Lactic Acid with Basic Extractants and Polymeric Sorbents

During recovery of product carboxylic acids from fermentation broths, it is important to maximize the selectivity for the desired acid, as opposed to substrate sugars. In this work uptakes of glucose and competitive uptakes of lactic acid and glucose have been measured for the extractant Alamine 336 in various diluents and three commercially available basic solid polymeric sorbents. The results show that swelling is the main factor governing the selectivity between lactic acid and glucose for the polymeric sorbents. Because of a high uptake capacity and relatively low swelling, Dowex MWA-1 gives a higher selectivity in the pH 5−6 range than do Amberlite IRA-35 and Reillex 425. Extraction with Alamine 336 provides a much higher selectivity, but a lower capacity, than the polymeric sorbents. The extent of water coextraction depends strongly on the diluent used, and larger amounts of water coextracted correspond to larger uptakes of glucose.

Extraction of carboxylic acids with amine extractants. 3. Effect of temperature, water coextraction, and process considerations

Coextraction of water during extraction of succinic acid by Alamine 336 in different dulents has been measured. The amounts of coextracted water lie in the same order as the solubilities of water in the diluents without amine present. Water coextraction with different acids follows the order fumaric>malonic>maleic=succinic>lactic>acetic. The effects of temperature on extraction of succinic and lactic acids by Alamine 336 with chloroform and methyl isobutyl ketone (MIBK) diluents have been measured. Enthalpies and entropies of complex formation have been derived from the results and are interpreted in terms of the differences in interactions among the species involved. Two approaches for regeneration through back-extraction into an aqueous phase are considered

HYDROFLUORIC ACID EXTRACTION BY TBP AND BY AMINES: MECHANISM, SPECIES FORMED AND UNIQUE PROPERTIES AT HIGH ACID TO AMINE MOLAR RATIOS

ABSTRACT Analysis of data concerning HF extraction by amines reveals a change in extraction mechanism when HF/amine molar ratio in organic phase (Z) reaches 2. Up to this point extraction is by ion-pair formation and after it by H-bonding. As a result, the two HF molecules initially extracted differ in nature from subsequent ones. The change in mechanism explains why seemingly unrelated properties such as water co-extraction dilution and diluent effects, selectivity and viscosity - all change when amine bifluoride composition is attained. Similar change in extraction of other mono-basic acids occurs at Z=1. The system with Z>2 for HF is equivalent to that with Z>1 for other mono-basic acids and to that of extraction by TBP. It therefore provides a model for extraction from concentrated aqueous solutions.

Metal replacement compounds

Enhancing the precipitation of Al(OH)3 from supersaturated sodium aluminate solution has been a challenge for the alumina industry for decades in its effort to increase the productivity. However, limited by the thermodynamic equilibrium of alumina solubility in caustic solutions, the processes that are available to date for promoting the precipitation of Al(OH)3 are unsatisfactory. An acid–base reactive solvent extraction method is proposed to enhance the separation of sodium hydroxide from sodium aluminate mother liquor by creating a condition for re-precipitation. The extraction process has been reported in Part I of this study by the present authors. In this paper the effects of diluents on sodium extraction when using 2-tert-butyl-4-methylphenol as the main organic extractant were systematically investigated. According to the classification of diluents, the capabilities for extracting sodium in different types of diluents were compared, and the protonic polar diluents were identified as being the most effective diluent. In the absence of alkyl phenol organic extractant, the sodium extraction equilibrium in 1-octanol and 2-ethyl hexanol, and the co-extraction of water in each of them were compared. In the presence of alkyl phenol, the extraction capabilities for sodium in different C8 alcohols, including 1-octanol, 2-ethyl hexanol and 2-octanol, were compared and analyzed. The results showed that 1-octanol is the most effective diluent among the three that are studied in this project. Furthermore, inert diluents including kerosene, octane and heptane, were used to dilute the pure 1-octanol solvent in different proportions in order to decrease the viscosity of the organic phase. The effects of the inert diluent on sodium extraction and water co-extraction were studied. Finally, the particle size distributions in the equilibrated organic phases and the Margules ternary 2-suffix equations were introduced to discuss the mechanisms of sodium extraction by 1-octanol and 2-ethyl hexanol. The results of this systematic research are expected to provide valuable guidance for the selection of diluents.

A thermodynamic model for the extraction of lithium from chloride brines containing aluminium and magnesium

The equilibrium constants for the extraction of lithium chloride, magnesium chloride and aluminium chloride by 1-hexanol and isopentyl alcohol were determined. For the joint distribution of the three salts between aqueous and organic solutions, a computer calculation based on a thermodynamic multicomponent electrolyte solution approach was applied. The coextraction of water was also taken into account. Predictions for the selective extraction of lithium were tested against experimental data, and reasonable agreement was found at low concentrations. The discrepancies observed at high chloride concentrations were ascribed to ion-pairing in the organic phase and to water co-extraction, possibly also to cation—cation interactions on the organicphase.