Üzek Recep, Şenel Serap, Denizli Adil
Department of Chemistry, Faculty of Science, Hacettepe University, 06800 Ankara, Turkey.
ACS Omega. 2022 May 24;7(22):18940-18952. doi: 10.1021/acsomega.2c01975. eCollection 2022 Jun 7.
Herein, a novel imprinted solid-phase extraction cartridge was fabricated to investigate the kinetic, thermodynamic, and isothermal parameters for the selective adsorption of Bisphenol A (BPA). The imprinted polymeric cartridges (BMC) for the BPA adsorption were fabricated in the presence of a template and functional monomer using the in situ polymerization technique. To prove the efficiency and selectivity of BMC, the nonimprinted polymeric cartridges (BNC) and the empty polymeric cartridges (EC) were also fabricated with and without functional monomer using the same manner for the preparation of BMC. The characterization of cartridges was performed by elemental analysis, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) surface area measurements, and swelling tests. BPA removal studies were performed by analyzing some parameters such as temperature, BPA concentration, flow rate, salt type, and concentration. The highest capacity was determined as 103.2 mg BPA/g polymer for a 0.75 mL/min flow rate of 0.75 M (NH)SO containing 200 mg/L BPA solution at 50 °C. NaOH (1.0 M) was used as a desorption agent. The reusability performance was examined by performing 10 consecutive cycles. The solid-phase extraction (SPE) performance was also checked to determine the enrichment and extraction recovery factors for tap water and synthetic wastewater samples. Temkin, Langmuir, Freundlich, and Dubinin-Radushkevich isotherm models were applied to BPA adsorption data examining the adsorption mechanism, surface properties, and adsorption degree. The most suitable isotherm model for BPA adsorption was determined as the Langmuir isotherm model. The thermodynamic parameters (Δ°, Δ°, and Δ°) were investigated to reveal the thermodynamics of adsorption. Adsorption thermodynamic parameters (Δ°, Δ°, and Δ°) were calculated using the thermodynamic equilibrium constant (thermodynamic equilibrium constant, °) values that change with temperature. It was determined that BPA adsorption was spontaneous (Δ° < 0) and endothermic (Δ° > 0) and entropy increased (Δ° > 0) at the temperatures studied in the BPA adsorption process. The rate control step in the adsorption process was examined by applying pseudo-first-order and pseudo-second-order kinetic models to the adsorption data for the investigations of BPA adsorption kinetics, and the pseudo-second-order kinetic model was found to be more suitable for describing BPA adsorption kinetics. In examining the selectivity of cartridges, structural analogues of hydroquinone, phenol, β-estradiol, and 8-hydroxyquinoline were tested.
在此，制备了一种新型印迹固相萃取柱，以研究双酚A（BPA）选择性吸附的动力学、热力学和等温线参数。采用原位聚合法，在模板和功能单体存在的条件下制备了用于BPA吸附的印迹聚合物柱（BMC）。为了证明BMC的效率和选择性，还采用与制备BMC相同的方法，分别制备了含功能单体和不含功能单体的非印迹聚合物柱（BNC）和空聚合物柱（EC）。通过元素分析、傅里叶变换红外（FTIR）光谱、扫描电子显微镜（SEM）、布鲁诺尔-埃米特-泰勒（BET）比表面积测量和溶胀试验对柱子进行了表征。通过分析温度、BPA浓度、流速、盐的类型和浓度等参数进行了BPA去除研究。在50℃下，对于流速为0.75 mL/min的含200 mg/L BPA的0.75 M (NH₄)₂SO₄溶液，测定的最大吸附量为103.2 mg BPA/g聚合物。使用NaOH（1.0 M）作为解吸剂。通过连续进行10个循环来考察其可重复使用性能。还检查了固相萃取（SPE）性能，以确定自来水和合成废水样品的富集和萃取回收率。将Temkin、Langmuir、Freundlich和Dubinin-Radushkevich等温线模型应用于BPA吸附数据，以研究吸附机理、表面性质和吸附程度。确定最适合BPA吸附的等温线模型为Langmuir等温线模型。研究了热力学参数（ΔH°、ΔG°和ΔS°）以揭示吸附的热力学性质。利用随温度变化的热力学平衡常数（K°）值计算吸附热力学参数（ΔH°、ΔG°和ΔS°）。结果表明，在研究的温度下，BPA吸附过程是自发的（ΔG° < 0）、吸热的（ΔH° > 0）且熵增加（ΔS° > 0）。通过将拟一级和拟二级动力学模型应用于BPA吸附数据，考察了吸附过程中的速率控制步骤，发现拟二级动力学模型更适合描述BPA吸附动力学。在考察柱子的选择性时，测试了对苯二酚、苯酚、β-雌二醇和8-羟基喹啉的结构类似物。
