| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 148087 | Chemical Engineering Journal | 2013 | 7 Pages |
•A Ca-montmorillonite was modified with DDTMA and HDTMA through direct ion exchange.•The prepared organoclays were characterized by XRD and BET instruments.•The adsorption conditions for BPA of organoclays were systematically studied.•The study provides a pathway for the removal of BPA from contaminated waters.
Organo Arizona SAz-2 Ca-montmorillonite was prepared with different surfactant (DDTMA and HDTMA) loadings through direct ion exchange. The structural properties of the prepared organoclays were characterized by XRD and BET instruments. Batch experiments were carried out on the adsorption of bisphenol A (BPA) under different experimental conditions of pH and temperature to determine the optimum adsorption conditions. The hydrophobic phase and positively charged surface created by the loaded surfactant molecules are responsible for the adsorption of BPA. The adsorption of BPA onto organoclays is well described by pseudo-second order kinetic model and the Langmuir isotherm. The maximum adsorption capacity of the organoclays for BPA obtained from a Langmuir isotherm was 151.52 mg/g at 297 K. This value is among the highest values for BPA adsorption compared with other adsorbents. In addition, the adsorption process was spontaneous and exothermic based on the adsorption thermodynamics study. The organoclays intercalated with longer chain surfactant molecules possessed a greater adsorption capacity for BPA even under alkaline conditions. This process provides a pathway for the removal of BPA from contaminated waters.
Graphical abstractThe surface properties of Ca-MMT were changed from hydrophilic to hydrophobic through intercalation with DDTMA and HDTMA. The adsorption of BPA onto organoclays is well described by pseudo-second order kinetic model and the Langmuir isotherm. This study demonstrates that the prepared organoclays are a promising adsorbent for environmental pollutants.Figure optionsDownload full-size imageDownload as PowerPoint slide
