Applied Chemical Engineering

Synthesis, characterization and adsorption properties of azo-functionalized polymeric hydrogels for R6G dye removal from water

Amna N. Zghair

Ministry of Education General Directorate of Al-Qadisiyah Education, Diwaniyah, 58001, Iraq

Ziyad T. Al-Khateeb

Department of Chemistry, College of Science, University of Al-Qadisiyah, 58001, Diwaniya, 58001, Iraq

Layth S. Jasim

Department of Chemistry, College of Education, University of Al-Qadisiyah, Diwaniyah, 58001, Iraq

Maryam Batool

Department of Chemistry, University of Sahiwal, Sahiwal, 57000, Pakistan

DOI: https://doi.org/10.59429/ace.v8i1.5604

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Abstract

In this study, 2- [2-(5-Chloro carboxy phenyl) azo] 1-methyl imidazole (1-MeCPAI) was synthesized and used in developing hydrogels via free radical polymerization with acrylic acid (AA) and N, N-methylene bisacrylamide. The synthesized P(AA-co-1-MeCPAI) hydrogels were evaluated for their effectiveness in adsorbing R6G dye from aqueous solutions. The characterization of these hydrogels included techniques as Fourier Transform Infrared Spectroscopy (FTIR), Thermal Gravimetric Analysis (TGA), BET (Brunauer-Emmett-Teller) and BJH (Barrett-Joyner-Halenda) analysis, X-ray diffraction (XRD), and Field Emission Scanning Electron Microscopy (FESEM). The study revealed that adsorption efficiency is influenced by pH, temperature, contact time, and adsorbent dose, with adsorption following a pseudo-second-order kinetic model and best fitting the Temkin isotherm, indicating a multilayer adsorption process. Thermodynamic analysis confirmed that the process is exothermic and spontaneous, underscoring the potential of P(AA-co-1-MeCPAI) hydrogels as effective adsorbents for dye removal.

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