Synthesis of eco-friendly Sp-EN-CPA adsorbent and its application for removal of Cr(VI) from aqueous solutions

In this study, environmentally friendly Sp-EN-CPA was synthesized to effectively remove Cr(VI) ions from aqueous solutions and wastewater. The Sp (sporopollenin) was successfully modified with ethylenediamine (EN) compound. Finally, 1,8-bis(3-chloropropoxy) anthracene-9,10-dion (CPA) compound was immobilized on the modified sporopollenin (Sp-EN). The structural and chemical properties of the newly synthesized Sp-EN-CPA adsorbent were characterized by scanning electron microscopy and Fourier-transform infrared spectroscopy images. The impact of experimental parameters such as concentration, contact duration, and temperature, adsorbent amount, and pH on the removal of Cr(VI) ions in the wastewater and aqueous solution were researched. Some adsorption isotherms were used to interpret the formation of the reaction of Cr(VI) ions attachment to the adsorbent surface. The effective elimination (97%) of Cr(VI) ions using Sp-EN-CPA compound was performed at pH 2. The maximum amount of Sp-EN-CPA for the adsorption of Cr(VI) ions in the wastewater and aqueous solution was found to be 0.075 g. Adsorption remained stable after 150 min. The Delta H degrees values of Cr(VI) ions in aqueous solution and wastewater in the 25 degrees C-50 degrees C temperature range were found to be 18.82 and 26.18 kJ mol(-1), and Delta S degrees values were found to be 103.79 and 123.01 kJ mol(-1), respectively. The average adsorption energy for the Sp-EN-CPA adsorbent was found to be 26.73 kJ mol(-1) for Cr(VI) ions in aqueous solution. Sp-EN-CPA exhibited an important achievement for the removal of Cr(VI) ions and can be suggested for the effectively elimination of Cr(VI) ions from the wastewaters.