Document Type : Original Article
Authors
1
Department of Chemical Engineering, College of Engineering, University of Baghdad, Baghdad, 10071, Iraq.
2
Department of Chemical Engineering, College of Engineering, University of Baghdad, Baghdad, 10071, Iraq
3
Department of Environmental Science, College of Energy and Environmental Science, Alkarkh University of Science, Baghdad, 10081, Iraq
4
Baghdad
Abstract
Gundelia is a genus of flowering plants native to the Mediterranean region, particularly in Iraq, that holds promise as a sustainable adsorbent for the treatment of dye-polluted water. This study explores the potential of Gundelia seeds (GS) waste as a biobased adsorbent for removing methylene blue dye from synthesized wastewater. Examination techniques, including Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and X-ray diffraction analysis (XRD), were utilized to assess GS’s activity. Although GS was used in its plain form, it showed comparable performance to complex-fabricated and expensive composites. Key parameters, such as pH (3-11), pH at the point of zero charge, temperature (298-328 K), dose (0.02-0.1 g), dye concentration (10-50 ppm), and contact time (10-40 min) were systematically investigated. The point of zero charge was determined to be at pH 8, with the highest removal efficiency observed at pH 11. Optimum conditions of a contact time of 30 minutes, does of 0.06 g, and dye concentration of 30 ppm yielded a removal rate of approximately 90%, with an adsorption capacity of 11.07 mg/g. However, the highest adsorption capacity, 30.57 mg/g, was attained under conditions of 50 ppm dye concentration, 0.02 g dose, and a 40-minute contact time. The study examined three isotherm models, namely Freundlich, Langmuir, and Temkin; all demonstrating a high fit, with Langmuir exhibiting preferability. On the other hand, five kinetic models were explored; the Pseudo second-order pattern provided the most accurate description of the adsorption process.
Keywords
Main Subjects
)