R. Sultana, A. Hussain, R. Sajjad, K. Shahzad, F. Haq, S. H. Park
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引用次数: 0
Abstract
Industrial effluents containing synthetic dyes represent a persistent environmental challenge due to their toxicity, chemical stability, and resistance to conventional wastewater treatment processes. In this study, a biodegradable starch based graft copolymer, carboxymethyl starch-graft-n-butyl methacrylate (CMS-n-BMA), was synthesized via free-radical polymerization and evaluated as an efficient adsorbent for the removal of Rhodamine 590 (Rh590) from aqueous solutions. Structural characterization using FTIR, XRD, SEM, and TGA indicated successful grafting of n-BMA onto CMS, resulting in reduced crystallinity, modified surface morphology, and improved thermal stability. The material exhibited excellent adsorption performance, achieving up to 99% removal efficiency under individually optimized conditions. Adsorption kinetics followed the nonlinear pseudo-second-order (PSO) model (R2 = 0.99), while equilibrium data were best described by the Langmuir isotherm model (R2 = 0.99), with a maximum adsorption capacity of 158.04 mg g−1. Thermodynamic analysis indicated that the adsorption process is spontaneous and endothermic. Mechanistic insights reveal that enhanced adsorption arises from synergistic electrostatic interactions and hydrogen bonding between cationic Rh590 molecules and functional groups within the graft modified polymer network. These findings highlight the role of graft modification in tuning adsorption behavior and demonstrate the potential of CMS-n-BMA for sustainable wastewater treatment applications.
Graphical Abstract
Schematic illustration of the adsorptive removal of Rh590 from contaminated water using the CMS-n-BMA adsorbent, and the proposed adsorption mechanism.
期刊介绍：
International Journal of Environmental Science and Technology (IJEST) is an international scholarly refereed research journal which aims to promote the theory and practice of environmental science and technology, innovation, engineering and management.
A broad outline of the journal''s scope includes: peer reviewed original research articles, case and technical reports, reviews and analyses papers, short communications and notes to the editor, in interdisciplinary information on the practice and status of research in environmental science and technology, both natural and man made.
The main aspects of research areas include, but are not exclusive to; environmental chemistry and biology, environments pollution control and abatement technology, transport and fate of pollutants in the environment, concentrations and dispersion of wastes in air, water, and soil, point and non-point sources pollution, heavy metals and organic compounds in the environment, atmospheric pollutants and trace gases, solid and hazardous waste management; soil biodegradation and bioremediation of contaminated sites; environmental impact assessment, industrial ecology, ecological and human risk assessment; improved energy management and auditing efficiency and environmental standards and criteria.
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