Parameters estimation for amino acids adsorption in a fixed bed by moment analysis

Cremasco, Marco Aurélio; Hritzko, Benjamin; Xie, Yi; Wang, N.H. L.

doi:10.1590/s0104-66322001000200006

Cited by 28 publications

(18 citation statements)

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“…The solute properties (D AB and k P ) presented in Table 2, and the physical parameters of the column, Table 3, are found in the literature (Cremasco et al, 2001). The axial dispersion coefficient, E b , and the external mass transfer coefficient, k f , are derived from the literature (Table 1).…”

Section: Resultsmentioning

confidence: 99%

“…The axial dispersion coefficient, E b , and the external mass transfer coefficient, k f , are derived from the literature (Table 1). The simulated curves are compared with experimental ones of Tyr and Phe, obtained by Cremasco et al (2001), in Figures 1 and 2, respectively. In both cases, two different flow rates were investigated: 1,0 ml/min (Q1) and 2,5 ml/min (Q2).…”

Section: Resultsmentioning

confidence: 99%

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Hybrid method of solution applied to simulation of pulse chromatography

Cremasco

Starquit

2009

Braz. J. Chem. Eng.

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-In this communication, the method proposed by Cremasco et al. (2003) is applied to predict single and low concentration pulse chromatography. In previous work, a general rate model was presented to describe the breakthrough curve, where a hybrid solution was proposed for the linear adsorption. The liquid phase concentration inside the particle was found analytically and related with the bed liquid phase through Duhamel´s Theorem, while the bulk-phase equation was solved by a numerical method. In this paper, this method is applied to describe pulse chromatography of solutes that present linear adsorption isotherms. The simulated results of pulse chromatography are compared with experimental ones for aromatic amino acid experiments from literature.

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Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Hybrid method of solution applied to simulation of pulse chromatography

Cremasco

Starquit

2009

Braz. J. Chem. Eng.

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“…The determination of these parameters can be based on the chromatographic parameters, such as the retention factor ( ) and the selectivity ( ). To obtain the isoenantioselective temperature it is necessary to know the porosity ( ), which was determined by moment analysis [10].…”

Section: Thermodynamic Parametersmentioning

confidence: 99%

“…If one simplifies the first absolute moment, the total porosity can be obtained experimentally. Therefore, total porosity is determined by (6), in which ] is superficial velocity and is bed length [10,14,15]…”

Section: Effect Of Temperature Equationmentioning

confidence: 99%

Thermodynamic Study of Racemic Ibuprofen Separation by Liquid Chromatography Using Cellulose-Based Stationary Phase

Ferrari

Nascimento

Moreira

et al. 2016

Chromatography Research International

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Ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID), also known for its significant antipyretic and analgesic properties. This chiral drug is commercialized in racemic form; however, only S-(+)-ibuprofen has clinical activities. In this paper the effect of temperature change (from 288.15 to 308.15 K) on the ibuprofen resolution was studied. A column (250×4.6 mm) packed with tris(3,5-dimethylphenylcarbamate) was used to obtain the thermodynamic parameters, such as enthalpy change (ΔH), entropy change (ΔS), variation enthalpy change (ΔΔH), variation entropy change (ΔΔS), and isoenantioselective temperature (Tiso). The mobile phase was a combination of hexane (99%), isopropyl alcohol (1%), and TFA (0.1%), as an additive. The conditions led to a selectivity of 1.20 and resolution of 4.55. The first peak, R-(−)-ibuprofen, presented an enthalpy change of 7.21 kJ/mol and entropy change of 42.88 kJ/K·mol; the last peak, S-(+)-ibuprofen, has an enthalpy change of 8.76 kJ/mol and 49.40 kJ/K·mol of entropy change.

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“…Moment analysis is widely used for the determination of the axial dispersion coefficient and mass transfer parameters from experimental breakthrough curves [11,12]. For dilute solutions, the first moment (l) yields the Henry's Law constant (K) in Eq.…”

Section: Moment Analysismentioning

confidence: 99%

Activated Carbon Adsorbent for the Aqueous Phase Adsorption of Amoxicillin in a Fixed Bed

et al. 2010

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Equilibrium constant and mass transfer parameters are needed for the study of amoxicillin separation in any process involving adsorption in fixed beds. In this work, the adsorption of amoxicillin and 6-aminopenillanic acid in aqueous solution on activated carbon were studied using static adsorption tests. The adsorption capacity was found to be strongly dependent on the pH of the aqueous phase. The adsorption constants, overall mass transfer coefficients, and axial dispersion coefficients for amoxicillin and 6-aminopenillanic acid were determined, by moment analysis, from a series of step tests in a fixed bed packed with activated carbon. The total bed voidage and axial dispersion coefficient were estimated from blue dextran pulse test data at different flow rates. The results show that adsorption intensity increased with increasing temperature. Furthermore, the increasing trend of HETP with velocity suggests that axial dispersion and mass transfer resistance control the column efficiency. IntroductionAmoxicillin, with molecular dimensions of 15.622 Å × 18.785 Å × 6.645 Å [1], is one of the major b-lactam antibiotics due to its high spectrum of activity, high solubility, high rate of absorption, and its stability under acid conditions. In the industry, the majority of semisynthetic b-lactam antibiotics are prepared by chemical methods. These reactions typically involve costly steps such as subzero degree Celsius conditions (-30°C), and toxic organic solvents like methylene chloride and silylation reagents [2]. Therefore, the enzymatic synthesis of semisynthetic antibiotics is an interesting industrial process, since it reduces the number of reaction steps and decreases the amount and toxicity of waste products per kilogram of antibiotic [3]. However, in the enzymatic production of amoxicillin at 25°C and pH 6.5, when the maximum yield of antibiotic production is achieved, the reaction media is composed of the desired product (the antibiotic), undesired products (resultant from hydrolysis), and unreacted substrates. The recovery of these biomolecules from bioreactors may involve several methods of extraction and purification, playing an important role in the global economic productive analysis of the process [4]. Adsorption is often used in downstream processing using various interactions, e.g., ionic, hydrophobic, affinity, etc., for the recovery of biomolecules, namely antibiotics [5]. Activated carbon and synthetic adsorbents have been used to remove biomolecules in the liquid phase [6][7][8], but no information is available on amoxicillin. Therefore, the purpose of this work is to study the separation of amoxicillin from reaction media as well as to evaluate the parameters of antibiotic adsorption onto activated carbon. Experimental Chemicals and ReagentsAmoxicillin was kindly donated by Royton Ltda, Brazil. 6-aminopenicillanic acid (6-APA) and blue dextran were supplied by Winlab and Sigma-Aldrich, respectively. All other reagents were of analytical grade from different commercial brands. AdsorbentActivated ...

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Parameters estimation for amino acids adsorption in a fixed bed by moment analysis

Cited by 28 publications

References 20 publications

Hybrid method of solution applied to simulation of pulse chromatography

Hybrid method of solution applied to simulation of pulse chromatography

Thermodynamic Study of Racemic Ibuprofen Separation by Liquid Chromatography Using Cellulose-Based Stationary Phase

Activated Carbon Adsorbent for the Aqueous Phase Adsorption of Amoxicillin in a Fixed Bed

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