The Characterization and Amoxicillin Adsorption Activity of Mesopore CaCO₃ Microparticles Prepared Using Rape Flower Pollen

• Main Authors: Lvshan Zhou, Tongjiang Peng, Hongjuan Sun, Xiaogang Guo, Dong Fu
• Format: Article
• Language: English
• Published: MDPI AG 2019-04-01
• Series: Minerals
• Subjects: calcium carbonate; mesopore; amoxicillin; adsorption; kinetics; thermodynamics
• Online Access: https://www.mdpi.com/2075-163X/9/4/254

A precipitation reaction method was employed to prepare mesopore calcium carbonate (CaCO₃) using rape flower pollen as the template. CaCO₃ adsorbent was characterized using X-ray diffraction (XRD), scanning electronic microscopy (SEM), and Brunner&#8722;Emmet&#8722;Teller measurements (BET). The equilibrium adsorption data on amoxicillin were explained using Langmuir, Freundlich, and Temkin adsorption isotherm models. The pseudo-first order, second order, pseudo-second order, and intra-particle diffusion kinetic models were used to explore adsorption kinetics. Equilibrium adsorption of as-prepared CaCO₃ was better depicted using the Langmuir adsorption model with an R² of 0.9948. The separation factor (<i>R_L</i>) was found to be in the range of 0 &lt; <i>R_L</i> &lt; 1, indicating the favorable adsorption of amoxicillin. The adsorption capacity of mesopore CaCO₃ reached 13.49 mg&#183;g^&#8722;1 in 0.2 g∙L^&#8722;1 amoxicillin solution. The values of adsorption thermodynamic parameters (&#916;<i>H</i>^&#952;, &#916;<i>S</i>^&#952;, &#916;<i>G</i>^&#952;) were obtained. In addition, the adsorption process turned out to be endothermic and spontaneous for the CaCO₃ product at 298 K, 308 K, and 318 K.