http://20.198.91.3:8080/jspui/handle/123456789/71 Sun, 05 Apr 2026 19:30:47 GMT 2026-04-05T19:30:47Z http://20.198.91.3:8080/jspui/handle/123456789/8956 Title: Intensification of catalytic conversion for production of fuel-additive Authors: Kar, Arpan Abstract: A novel nano-photocatalyst has been prepared using hydroxyapatite (HAp) derived from waste fish scale and fly ash derived aluminosilicate (SiO2-Al2O3) grafted with zirconium oxide (ZrO2) active sites by innovative photo-hydrothermal protocol. The physio-chemical properties of the prepared photocatalyst have been characterized by different analyses like XRD, FTIR, XPS, UV-VIS-NIR, BET, NH3-TPD, HRTEM, DLS and TGA. The optimal catalyst has Zr loading of 20 wt% and has a low bandgap energy of 2.15 eV as confirmed by UV-VIS-NIR spectroscopy. The optimal catalyst also depicted a high acidity of 1.52 mmol NH3/g and a specific surface area of 62.872 m²/g. Owing to the high acidity, specific surface area and low band gap energy the photocatalyst has led to achieve a yield of 76.6% levulinic acid (LA) from glucose in hybrid radiation reactor (HRR) deploying UV and FIR irradiation at appreciably low temperature and reaction time of 115℃ and 2h respectively. Under the same reaction conditions, the conventionally heated reactor (CHR) gave a very low yield of 23.7 %. Individual radiation effects on LA yield evinced the synergistic advantageous effect of hybrid radiation technique. The catalyst reusability and regenerative study confirmed the high stability of the prepared catalyst. Also, a comparative LCI study has been conducted between HRR and CHR systems which revealed that HRR is more environmentally sustainable than CHR. HRR based process demonstrated a 59% lower global warming potential, 65% lower terrestrial ecotoxicity while being 120% more energy efficient than CHR based reaction making HRR more environmentally sustainable as well as economically feasible. This study also focused on the synthesis of ethyl levulinate (EL) from glucose in ethanol medium, utilizing various catalytic systems. To replace conventional heating, a hybrid radiation system combining UV and IR was implemented. The optimization of key reaction parameters, such as reaction temperature (140 ℃), reaction time (45 mins), catalyst loading (30 wt%), and glucose-to-ethanol molar ratio (90), was achieved using a Taguchi L9 orthogonal design. At the optimized conditions, the maximum EL yield of 76.08% with 100% selectivity was obtained using an Amberlyst-36 + TiO2 (2:1) catalytic system. Furthermore, the synthesized EL was blended with biodiesel and commercial diesel at different ratios to evaluate engine performance and emission quality. The B7E3 blend exhibited favorable results, demonstrating a significant reduction of 19% and 18.86% in hydrocarbon (HC) and carbon monoxide (CO) emissions, respectively, compared to the other blends. Additionally, the B7E3 blend showcased lower brake specific fuel consumption (BSFC) and higher brake thermal efficiency (BTE). Furthermore, a life cycle assessment (LCA) was performed to evaluate the environmental impacts of EL production. in a conventional reactor (ELCH) in comparison to a hybrid radiation reactor (ELHR). The findings revealed that the ELHR significantly reduced global warming potential (GWP) by 48.86% compared to the ELCH, while also exhibiting a five-fold reduction in energy consumption. Overall, this study provides a comprehensive analysis of EL synthesis, engine performance, emission characteristics, and environmental implications, emphasizing the advantages of the hybrid radiation system over conventional heating methods. Sun, 01 Jan 2023 00:00:00 GMT http://20.198.91.3:8080/jspui/handle/123456789/8956 2023-01-01T00:00:00Z http://20.198.91.3:8080/jspui/handle/123456789/8953 Title: Adsorptive removal of norfloxacin from aqueous solution by reduced graphene oxide anchored copper ferrite composite Authors: Saha, Aditya Abstract: Unrestricted discharge of pharmaceuticals and their waste in the surrounding and the contamination of the aquatic environment are one of the burning topics in pollution-removing research works. In this research paper adsorption method is employed for which a novel adsorbent reduced graphene oxide based copper ferrite is prepared by wet method to remove Norfloxacin which is 3rd generation antibiotic and also found in the environment in significant amounts from aqueous solution. The SEM micrograph demonstrates that copper ferrite was successfully deposited on the reduced graphene oxide flakes. The EDS result demonstrates the presence of copper and iron metal in the adsorbent. The maximal reduction of graphene oxide into reduced graphene oxide has been detected using XRD data. The XRD examination of copper ferrite has proven that CuFe2O4 and a trace amount of CuO were formed. According to the FTIR analysis, as graphene oxide reduces to form reduced graphene oxide, fewer oxygen-containing functional groups are present. BET analysis was done to find out the pore volume and surface area of the adsorbent. The highest removal efficiency was found to be 90.55%. The process followed the Langmuir isotherm which gives the maximum adsorption capacity of 296.74 mg.g-1. Pseudo-second-order kinetics was best fitted for the process. After 5 cycles of regeneration of the adsorbent, a minor drop in removal efficiency was observed. Sun, 01 Jan 2023 00:00:00 GMT http://20.198.91.3:8080/jspui/handle/123456789/8953 2023-01-01T00:00:00Z http://20.198.91.3:8080/jspui/handle/123456789/8950 Title: Preparation, chracterization and application of mixed matrix membrane for heavy metal removal from waste water Authors: Chakraborty, Parambrata Abstract: Removal of heavy metal ions from wastewater is of prime importance for a clean environment and human health. Different reported methods were devoted to heavy metal ions removal from various wastewater sources. These methods could be classified into adsorption, membrane separation, chemical, electric, photocatalytic-based treatments. Wastewater treatment using mixed matrix membrane could provide tremendous results as it could play two roles in pollutant removal by covering adsorption and size exclusion of water contaminants simultaneously. Ceramic membranes with excellent thermal and chemical stability, mechanical strength, fouling resistance are most suitable for wastewater treatment. Sun, 01 Jan 2023 00:00:00 GMT http://20.198.91.3:8080/jspui/handle/123456789/8950 2023-01-01T00:00:00Z http://20.198.91.3:8080/jspui/handle/123456789/8946 Title: Development of organic CdS/spinacia oleracea based photocatalyst for bioconversion and remarkable production of hydrogen Authors: Biswas, Ayantan Abstract: Photocatalytic Hydrogen generation from Biomass is an emerging approach to produce renewable Hydrogen. The objective of this study is to produce green hydrogen from biomass with the help of full band solar irradiation which can be used as fuel and can substitute the fossil fuels in the coming days. Here, a biomass based photocatalyst has been synthesised, characterized and evaluated for the Hydrogen generation using a full band solar spectrum. The Hybrid photocatalyst CdS/Spinacia Oleracea has been tested for hydrogen generation via photocatalytic water splitting under full band solar irradiation. The Spinacia Oleracea is known for its high amount of chlorophyll, which act as photosensitizer in the hybrid photocatalyst. The synthesised photocatalyst were characterised using different morphological and optical tools like FE-SEM, EDX, XRD, TEM, UV-Vis and PL spectroscopy. The synthesised photocatalyst (CdS/Spinacia Oleracea) has been shown higher hydrogen generation than the pristine CdS photocatalyst. It has been shown that the activity of synthesised photocatalyst has been increased nearly six times than the pristine photocatalyst. The solar full band irradiation activity of the CdS/Spinacia Oleracea photocatalyst is measured to be 29.80 mmol g-1 h-1, which is higher than the activity of pristine CdS, which is 4.59 mmol g-1 h-1. The Apparent quantum efficiency of CdS/Spinacia Oleracea is 18.21% at 420 nm and 15.63% at 350 nm of Band Pass Filter using solar simulator. A proposed mechanism has been also forwarded showing improved electron-hole separation and low charge recombination. These type of low cost photocatalyst having high green Hydrogen generation performance result to industrial and scale up applications. Sun, 01 Jan 2023 00:00:00 GMT http://20.198.91.3:8080/jspui/handle/123456789/8946 2023-01-01T00:00:00Z