Design and synthesis of biodegradable polymeric catalysts for industrial dye degradation

Thesis Abstract

The escalating release of industrial dyes into aqueous environments has emerged as a critical environmental challenge, owing to their persistence, known toxicity, and resistance to conventional wastewater treatment methods, thereby necessitating the development of sustainable, effective remediation strategies. This study aims to design, synthesize, and evaluate biodegradable polymeric catalysts capable of catalyzing the degradation of various industrial dyes efficiently, with a focus on eco-friendly materials and processes. Specific objectives include synthesizing a series of bio-based polymeric catalysts derived from renewable sources such as polysaccharides and polyesters, characterizing their structural and catalytic properties, and assessing their performance in degrading common dyes like methylene blue, Congo red, and malachite green through batch and continuous flow experiments. The research employed an experimental research design, centered on the synthesis and characterization of polymeric catalysts, applying a quasi-experimental framework to assess catalytic efficacy under controlled laboratory conditions. The population comprised synthesized biodegradable polymers, with a sample size of 30 catalyst formulations prepared via solvent casting, in-situ polymerization, and crosslinking techniques. Analytical characterization was conducted using Fourier Transform Infrared Spectroscopy (FTIR), Nuclear Magnetic Resonance (NMR), Scanning Electron Microscopy (SEM), and Brunauer–Emmett–Teller (BET) surface area analysis to elucidate structural features and surface morphology. The degradation efficiency was quantified through spectrophotometric measurements of dye concentrations at specific wavelengths, with data analysis involving analysis of variance (ANOVA) to compare degradation rates across catalyst formulations, and regression analysis to model the relationship between catalyst properties and degradation efficiency. Key expected findings include the identification of specific biodegradable polymeric catalysts exhibiting superior catalytic activity, achieving degradation efficiencies exceeding 85% within 60 minutes for targeted dyes under optimal conditions. The catalysts are anticipated to demonstrate high stability and reusability over at least five cycles, with degradation rates strongly correlated to surface area, functional group availability, and porosity, as elucidated via SEM and BET analyses. The study also expects to reveal the influence of catalyst synthesis parameters, such as crosslinking density and polymer composition, on catalytic performance, aligning with the theoretical frameworks of surface catalysis and Green Chemistry principles. This research contributes significantly to the body of knowledge by providing innovative, environmentally benign catalysts for industrial wastewater treatment, integrating principles of sustainable chemistry, and advancing the application of biomass-derived polymers in catalysis. It offers a comprehensive understanding of the relationships between polymer structure and catalytic activity, filling gaps identified in prior empirical studies regarding the scalability and practical deployment of biodegradable catalysts in real-world settings. The main conclusion emphasizes the feasibility of utilizing biodegradable, renewable polymeric catalysts to degrade toxic dyes efficiently, thereby reducing environmental pollution and fostering sustainable industrial practices. Recommendations include further optimization of catalyst synthesis parameters to enhance degradation rates, pilot-scale testing in industrial effluent streams, and exploring the potential for functionalization to target a broader spectrum of pollutants. Future studies should also investigate the long-term stability and disposal considerations of these catalysts to facilitate their integration into existing wastewater treatment systems, making a substantial contribution toward eco-friendly and cost-effective textile and dye manufacturing processes.