Experimental and Theoretical Study on Adsorption Mechanism of Polyvinylpolypyrrolidone (PVPP) for Effective Phenol Removal in an Aqueous Medium

• Main Authors: Mohammad Alwi, Muhammad Ammar, Ismail, Hakimah, Abdullah, Erna Normaya, Ahmad, Mohammad Norazmi
• Format: Conference or Workshop Item
• Language: English; English
• Published: 2021
• Subjects: QD Chemistry
• Online Access: http://irep.iium.edu.my/92452/1/92452_Experimental%20and%20Theoretical%20Study%20on%20Adsorption%20Mechanism.pdf; http://irep.iium.edu.my/92452/2/92452_Experimental%20and%20Theoretical%20Study%20on%20Adsorption%20Mechanism_programme%20book.pdf; http://irep.iium.edu.my/92452/; https://umevent.um.edu.my/SKAM33
• Institution: Universiti Islam Antarabangsa Malaysia

Phenol is considered as environmental priority pollutants and widely present in the wastewater generated from various sources such as industries. This research focuses on the ability of polyvinylpolypyrrolidone (PVPP) in removing phenol from aqueous medium. Two pH aqueous medium was investigated which are 3.5 and 6.5. The result showed PVPP was better in removing phenol at pH 6.5 than pH 3.5 with 74.91 % and 66.54 % respectively. The kinetics and equilibrium adsorption data of phenol by PVPP well fitted to the Langmuir isotherm (R2=0.9905) and pseudo second order model (R2=0.9925). Then, the study by using 1D and 2D IR spectroscopy showed the adsorption mechanism PVPP–phenol complex where the response peaks of the hydroxyl groups of phenol (OH) and the carboxyl groups (C=O) of PVPP were altered, which signified the formation of a hydrogen bond in between PVPP and phenol. Density functional theory (DFT) was calculated to determine the potential energy, quantum chemical, electronic energy, bond angles, bond lengths and Mulliken charges in the solution phase. Furthermore, COSMO RS and RDG-NCI result showed the conformation of the presence of hydrogen bond interactions between PVPP and phenol. Then, the global and local quantum chemical descriptors clarified that PVPP acts as a nucleophile, while phenol acts as an electrophile. The result indicated also the O9 atom (donor electron) reacts with the H22 atom (acceptor electron) during the formation of hydrogen bond in removing of phenol.