Article Cite This: J. Chem. Eng. Data XXXX, XXX, XXX-XXX
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Adsorption Equilibrium, Kinetics, and Thermodynamic Studies of Cefpirome Sulfate by Using Macroporous Resin Feng Xue, Fugang Wang, Shuai Chen, Shengui Ju,* and Weihong Xing College of Chemical Engineering, Nanjing Tech University, Nanjing 210009, People’s Republic of China S Supporting Information *
ABSTRACT: The adsorption thermodynamics, kinetics, and isotherm parameters of cefpirome sulfate in aqueous solution on macroporous resin (XAD-16) were studied. Using static equilibrium tests, the fitting of resin adsorption data were calculated by the isothermal adsorption model. The fitting results show that Freundlich equation can adequately fit the adsorption isotherm. Meanwhile, the derived adsorption constants and their temperature dependencies from Freundlich isotherm had been used to calculate the corresponding thermodynamic quantities, such as the free energy of adsorption, heat, and entropy of adsorption. The thermodynamic data indicated that XAD-16 resin adsorption of cefpirome sulfate in aqueous solution was a spontaneous exothermic process, which was characterized by physical adsorption. The influences of initial concentration, bed height, and residence time on the breakthrough curve were examined by dynamic tests and the optimal parameters were defined.
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INTRODUCTION Cefpirome sulfate, as the fourth-generation cephalosporin, not only has an advantage of the third-generation cephalosporins but also has high affinity to penicillin binding protein. The chemical structure is shown in Figure 1. It has also possessed
described quantitatively by adsorption kinetics. The design of the adsorption facilities, the adsorption types and mechanisms are crucial for this experiment.7 External diffusion (film diffusion), intraparticle diffusion (pore diffusion), and the internal-surface diffusion of the adsorbent are three types of diffusions of the molecules in the macroporous resin.8,9 Casillas et al.10 studied the kinetics model in two ways, including a single effective internal diffusion coefficient and the linear adsorption isotherm. In the experiment, they eliminated the other influence factors by agitating method, thus fitting the Sherwood number effectively. Yang et al.11 pointed out the differences between pore diffusion and surface diffusion, and estimated the values using the nonlinear regression and “the half-time” methods. However, there is a long way to go for the simplification of diffusion coefficient in the field of engineering application. In the general of the adsorption process, the influence of the internal-surface diffusion is usually ignored because of its fast diffusion rate. To simplify the adsorption process, the influence of the external diffusion can be eliminated by the method of shanking. Therefore, the internal-particle diffusion is considered as the kinetically controlled step. The internal-particle diffusion coefficient can be fitted by the Crank model.12 In addition, the single effective diffusion coefficient in particle diffusion is often used to describe the mass transfer behavior in the adsorbent.13,14 There are several methods for estimating the liquid film mass transfer
Figure 1. Chemical structure of cefpirome sulfate.
other advantages including high concentration in bacteria periplasm, and low affinity for β-lactamase of chromosome, significant effect for multiple drug-resistant bacteria, Gramnegative and Gram-positive bacteria, etc.1 The strong activity to resist aerobic Gram-negative bacteria and anaerobic bacteria makes it a pharmacokinetic long-acting drug. Due to the side effects of β-lactams caused by the generation of degradation products, it is important to estimate the stability of cephems.2−5 The method of adsorption by macroporous resin has the advantages of simple equipment, convenient operation, energy saving, high product purity, and no moisture absorption. It has been widely used in the research and production of traditional Chinese medicine.6 The Rohm and Haas resin used in this article has a high exchange capacity, strong antioxidant properties, excellent kinetic properties, and antifouling properties. The adsorption process of cefpirome sulfate can be © XXXX American Chemical Society
Received: July 12, 2017 Accepted: November 15, 2017
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DOI: 10.1021/acs.jced.7b00629 J. Chem. Eng. Data XXXX, XXX, XXX−XXX
Journal of Chemical & Engineering Data
Article
Table 1. Physical Properties of Three Resins resin
polymer matrix
polarity
bead size/μm
pore diameter/nm
BET surface area/m2/g
specific gravity/g/mL
XR-935C HP-20 XAD-16
polystyrene polystyrene polystyrene
weak-polar nonpolar nonpolar
300−1250 783 600−750
150−200 93 15
1000 500−600 800
1.05−1.15 1.03−1.07 1.06−1.08
(GL Science Co. Ltd., 180 × 4.6 mm i.d., 5.0 μm) chromatographic column was used. The column oven temperature was set at 295 K. The mobile phase was consisted of ammonium dihydrogen phosphate and acetonitrile (90:10, v/v) and flowed through the column in 15 min with the flow rate of 1.0 mL/min. Meanwhile, the detection wavelength was 254 nm.
coefficient (kf).13−15 For the condition of 0.1
