http://hdl.handle.net/2080/19 2026-06-30T04:06:46Z 2026-06-30T04:06:46Z Gopal, Sreeshma Sen, Sujit http://hdl.handle.net/2080/5829 2026-06-24T10:59:48Z 2026-06-01T00:00:00Z

Title: Remediation of Microplastics from Water Sources with Zeolite Y Derived from Aluminosilicate Industrial Wastes Authors: Gopal, Sreeshma; Sen, Sujit Abstract: Microplastics (MPs) are minute polymeric particles generated by abiotic and biotic stress and gradual plastic degradation. Their nonbiodegradability and widespread dispersion, especially in aquatic environments, make eradication a major environmental concern. The diminutive size of MPs facilitate their transfer through multiple filtration systems, complicating their removal from water. Significant long-term health risks have been detected in several human tissues due to MPs. This study aims for the remediation of MPs mainly polypropylene from water by the zeolite Y synthesized from aluminosilicate industrial waste (coal fly ash) through adsorption method, both prepared through sono assisted process. Zeolite composites, integrated with appropriate functional components, are also synthesized for comparative analysis and to enhance efficacy and recovery rates. Zeolite serves as an excellent porous adsorbent material for the adsorption of MPs due to the negative charge of MPs. The removal efficiency was found 94.95% at 2 ppm concentration of MPs, adsorbent dosage of 10 mg and at pH 7. The experimental data from the adsorption kinetic study was well fitted with pseudo-second order kinetic model with R2 value 0.99982 and from the adsorption isotherm study was fitted the best with Langmuir isotherm model with R2 value 0.99843. XRD, FESEM, EDX, Raman and FTIR confirmed 91.38% crystallinity, tetrahedral morphology, elemental composition and has a Si/Al ratio more than 1.5, with appropriate functional groups respectively. Surface area is determined to be 525.862 m²/g by BET and the lattice pattern and porous structure was identified by HR-TEM. Description: Copyright belongs to the proceeding publisher.

2026-06-01T00:00:00Z Pattnaik, Surya Chowdhury, Pradip http://hdl.handle.net/2080/5828 2026-06-23T10:52:22Z 2026-06-01T00:00:00Z

Title: Performance Evaluation of Biochar and Ash Based Catalysts Derived from Waste Flower Source for Biodiesel Synthesis Authors: Pattnaik, Surya; Chowdhury, Pradip Abstract: There are widely used sources for deriving heterogeneous catalysts from biomass such as leaves, shells, branches, stems, seeds etc. Flowers as a source for catalyst is less explored. Most biochar utilized as a catalyst in transesterification reactions is supported/chemically modified to improve its characteristics and performance. On the other hand, ash from biomass is very less studied and can be a sustainable and green material in catalytic reactions. In this study, Mussaenda philippica (MP) waste flower bracts were chosen for synthesizing catalyst. MP flowers were collected from the NIT Rourkela campus, sun dried and then treated in muffle furnace at 700 °C for 2 hours with lid on the crucible to get biochar and at 400 °C for 2 hours without lid to obtain ash. EDX result showed that K present was 23.15% and Ca was 3.18% in biochar. In ash, 35.24% K and 8.7% Ca were present. BET analysis showed that the surface area of biochar was 97.632 m2/g and of ash was 11.12 m2/g. The transesterification reaction of non- edible sesame oil using biochar as catalyst didn’t succeed, whereas using ash-based catalyst gave a positive result. This is due to presence of high combined percentage of K and Ca in the ash. NMR, FTIR and GCMS analyses were performed to confirm the unsuccessful/successful conversion of biodiesel. Various physico-chemical properties have been evaluated and were well under ASTM and EN standards. The future scope of the study is to activate/modify the biochar for enhancing its properties and performance as catalyst. Description: Copyright belongs to the proceeding publisher.

2026-06-01T00:00:00Z Patnaik, Rupak Kumar Sen, Sujit http://hdl.handle.net/2080/5827 2026-06-23T10:52:10Z 2026-06-01T00:00:00Z

Title: Deep Eutectic Solvent–Assisted Green Synthesis of a Covalent Organic Framework Via a Novel Sustainable Route Authors: Patnaik, Rupak Kumar; Sen, Sujit Abstract: Covalent organic frameworks (COFs) are crystalline porous polymers that allow precise assembly of organic units into predetermined skeletons and nanopores, combining structural tunability, extended conjugation, light-harvesting ability and semiconducting behaviour [1]. In this study, a β-Ketoenamine COF was synthesized via a novel green synthesis using a PTSA-based deep eutectic solvent (DES) as the reaction medium. XRD under varied reaction conditions identified 1:1.5 PTSA DES:H₂O, 24 h, and 120°C as the optimal parameters for high crystallinity. FTIR confirmed formation of the characteristic β-Ketoenamine linkages, while Raman and solid-state NMR spectra showed all relevant COF peaks. The optimised sample achieved a high isolated yield of 83.49%. N₂ sorption revealed a BET surface area of 698.69 m² g⁻¹ and a BJH pore diameter of 2.8 nm, confirming a mesoporous framework. XPS survey spectra verified the presence of carbon, nitrogen, and oxygen in the expected stoichiometry. High-resolution XPS C1s, O1s and N1s spectra exhibited peaks at 284.1, 285.5, and 287.2 eV, at 530.4, 531.8 eV, 399.7 and 402.4 eV attributable to the C–C/C═C, C–N, C═O, C=O and C-O-H, C-N bond and π-π* transition of COF. FESEM images of COF-120 displayed a cross-linked fibrous network connected by wire-like domains, consistent with strong π–π stacking between neighbouring rods; analogous cross-linking was observed by HRTEM. TGA indicated excellent thermal stability up to 400°C. Optical analysis showed that COF-120 was active under visible light, indicating that the DES-synthesised β-Ketoenamine COF is a promising candidate for photocatalytic applications. Description: Copyright belongs to the proceeding publisher.

2026-06-01T00:00:00Z Tripathy, Hritankhi Kumar, Arvind http://hdl.handle.net/2080/5826 2026-06-23T10:51:57Z 2026-06-01T00:00:00Z

Title: Indium QD Based 3D Sustainable Hydrogel as A Multifunctional Material for Photocatalytic Environmental Remediation & Energy Production Via Energy Storage Authors: Tripathy, Hritankhi; Kumar, Arvind Abstract: The synthesis of multifunctional sustainable materials for simultaneous remediation of the environment and energy application are crucial aspects that must be considered for future advanced water treatment techniques. In this study, we present a new sustainable InQD/polypyrrole(PPy) incorporated sodium alginate flexible hydrogel that acts as a multifunctional three-dimensional Flexible Hydrogel for photocatalytic wastewater purification via photo-energy storage and simultaneous energy production. Comprehensive characterization confirmed the successful formation and integration of the photocatalyst within the hydrogel matrix. Once the hydrogel is exposed to light, photogenerated electrons and holes are formed in InQD, and electrons are harvested by the PPy network, where they are stored for later use, allowing continued photocatalysis even after the removal of light. Studies on photocatalysis using SMX as an emerging pollutant model achieved a 98% degradation rate within 60 minutes, with significant degradation occurring even in darkness following only 10 minutes of irradiation. Furthermore, the hydrogel was shown to produce H₂O₂ in situ at a rate of 411 μM, which can be utilized for advanced oxidation processes producing various reactive oxygen species. Electrochemical analysis showed improved charge separation and low charge transfer resistance, as well as excellent capacitance performance. Finally, due to its high flexibility and durability, the hydrogel can be easily integrated into various small and confined structures without breaking. This research demonstrates a novel self-sustained photocatalytic hydrogels that can degrade pollutants continuously even in darkness, making them a promising platform for intelligent environmental pollution remediation systems. Description: Copyright belongs to the proceeding publisher.

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