https://repository.ju.edu.et//handle/123456789/3627 Mon, 06 Apr 2026 00:04:10 GMT 2026-04-06T00:04:10Z https://repository.ju.edu.et//handle/123456789/9525 Statistical optimization characterizations and Eco- friendly synthesis of silica from sugarcane bagasse Habte, Girma Assefa; Bullo, Tafere Aga; Ahmed, Yasin This research explores the synthesis and optimization of Silica have been effectively produced from sugarcane bagasse (SB) using the sol-gel methods. Due to its rich silica content, sugarcane bagasse can be utilized as a viable alternative source for silica synthesis. Employing Central Composite Design, the study systematically varied combustion temperature (500–800 °C), combustion time (2–4 h), and digestion time (1–3 h) to enhance silica yield. The optimal conditions identified were a combustion temperature of 583.48 °C, a combustion time of 3.482 h, and a digestion time of 2.283 h, resulting in a silica yield of 69.6%. Comprehensive characterization of the synthesized silica was conducted through Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Brunauer, Emmett, Teller model (BET) analysis and Thermo-gravimetric Analysis (TGA). XRD results indicated the amorphous nature of the silica, with a broad peak at 22.36°, akin to that of commercial silica. FTIR analysis revealed six characteristic peaks at wavenumbers corresponding to those found in commercial silica, confirming the presence of similar chemical groups. SEM imagery illustrated a disordered arrangement of silica with undefined morphology. The TGA analysis shows high thermal resistivity of silica with only 9% weigh loss at 800 °C. Overall, this study demonstrates that high-quality silica can be produced from sugarcane bagasse with minimal chemical input and energy consumption and highlighting its potential for diverse applications. Wed, 01 Jan 2025 00:00:00 GMT https://repository.ju.edu.et//handle/123456789/9525 2025-01-01T00:00:00Z https://repository.ju.edu.et//handle/123456789/9522 Green synthesis of Silver‑iron‑zinc oxides nanocomposite via Embelia schimperia leaf extract for photo‑degradation of antibiotic drug from pharmaceutical wastewater Gizachew, Defar Getahun; Jiru, Edo Begna; Tekle’Ab, Tsigab; et al. The co-precipitation approach is used in the current study to create an environmentally friendly Ag/Fe/ZnO nanocomposites utilizing an aqueous leaf extract of Embelia schimperia. The synthesized nanocomposite was characterized using Fourier transform infrared, UV, X-ray, UV–vis, DLS, TGA, and SEM to determine its functional group, structure, bandgap energy, size distribution, a mass of loss, and energy gain or loss, and morphological structure, respectively. The bioactive compo nents of Embelia schimperia, synthesized Ag/Fe/ZnO NCs and degradation of Amoxicillin via photocatalyst were assessed. The response surface methodology of central composite design (CCD) was used to examine and optimize the effects of three independent variables on the degradation of Amoxicillin under visible light. According to the experimental findings, the maximum photocatalytic degradation efficiency was achieved at green synthesized Ag/Fe/ZnO NCs dosage of 100 mg, a concentration of Amoxicillin of 30 mg/L and a radiation time of 180 min. Their findings show that Embelia schimperia extract-derived Ag/Fe/ZnO nanocomposites is a promising alternative for degradation of pharmaceuticals contamination of wastewater via photocatalytic under the given conditions. Mon, 01 Jan 2024 00:00:00 GMT https://repository.ju.edu.et//handle/123456789/9522 2024-01-01T00:00:00Z https://repository.ju.edu.et//handle/123456789/9164 Green synthesis of Silver Iron Zinc oxides Nanocomposite using Embelia Schimperia leaf extract for removal of ciprofloxacin from aqueous solution and antibacterial activity. Defar Getahun; Edo Begna; Tsigab Tekleab Green-synthesis of metal-oxide nanocomposites is the synthesis from bioactive agents like plant microorganisms, and various bio-wastes, which are used for different applications such as wastewater treatments, degradation of dyes, antibacterial activity and reduction of the toxic metal. Pharmaceutic drug waste is one most pollutants in water quality which brings a chronological effect on fish, animals, human beings, and plants. To treat wastewater, conventional methods such as sedimentation, flotation, coagulation, and adsorption are utilized. However, pharmaceutical medicines in wastewater cannot be fully treated using these old methods. As a result, modern advanced photo catalytic process were used to treat these pharmaceutical drugs in wastewater. Removal of pharmaceutical wastewater by Photo catalysis process using green synthesized metal oxide nanocomposite is the most preferable one, less costly, eco-friendly, and simple process. This study was synthesize, optimize and characterize the Ag/Fe/ZnO Nanocomposite from Embelia schimperia leaf as a reducing agent within silver nitrate, iron chloride, and zinc acetate dehydrated as a precursor. The synthesized Ag/Fe/ZnO NCs were made at three operating condition such as pH (8-12), Temperature (55-90oC) and precursor concentration (0.05-0.1M). Response surface methodology used to analyze statistical experimental data at these three factors. The parameters such as pH 11.46, temperature 55 oC, and 0.099M of concentration of precursor were the optimum condition obtained for synthesized of Ag/Fe/ZnO NCs. The synthesized Ag/Fe/ZnO NCs was characterized by UV-Visible Spectrophotometer, Fourier transform infrared Spectrophotometer, X-ray diffraction spectroscopy, Dynamic Light Scattering, Scanning Electron Microscopy and Thermal Gravimetric Analysis. Finally, Ag/Fe/ZnO NCs were used to degrade ciprofloxacin medication using a 15W light source; Ag/Fe/ZnO NCs degrade 85% of ciprofloxacin. Ag/Fe/ZnO NCs also evaluated for antibacterial activities against E. coli, S. typhi, B. cereus, and S. aureus bacteria, with the results showing that the antibacterial activities is extremely efficient. Therefore, this study confirms that green synthesized of Ag/Fe/ZnO NCs used for both applications of removal of ciprofloxacin in aqueous solution and antibacterial activity. Mon, 01 Jan 2024 00:00:00 GMT https://repository.ju.edu.et//handle/123456789/9164 2024-01-01T00:00:00Z https://repository.ju.edu.et//handle/123456789/9162 Aspen HYSYS Simulation for Biodiesel Production from Castor Seed Oil using Calcium Oxide Nanocatalyst and Its Purification Via Micro Membrane Filtration Alefa, Yoseph Tesfaye; Begna, Edo; Mekonnen, Yigezu Biodiesel is a promising renewable energy source, that holds potential for replacing conventional fuels with reduced environmental impact. In this study, biodiesel is produced via a transesterification process from castor seed oil extracted by the Soxhlet extraction method. The transesterification process employed a calcium oxide nano-catalyst synthesized from eggshell waste. Optimization of process parameters through Response Surface Methodology (RSM) considers temperature (40°C, 50°C, 60°C), reaction time (60 minutes, 75 minutes, 90 minutes), catalyst load (1%, 1.5%, 2), and methanol to oil ratio (1:6, 1:9, 1:12) at three levels for each. Experimental results validate RSM predictions, achieving a 97% biodiesel yield under optimal conditions (60°C temperature, 75-minute reaction time, 1.5% catalyst loading, and 1:9 oil-to methanol ratios). The research extends to the purification process, employing micro membrane filtration with varying pore sizes (0.1 µm, 0.22 µm, and 0.45 µm) to minimize water usage and environmental impact. Physiochemical properties of biodiesel: density (0.9138g/ml), FFA (0.0.356 ± 0.11%), saponification value (180.52mg KOH g/g oil), Heating value (41.063MJ/kg), and Iodine value (80.52 g of I2 / 100g of fuel) are aligned with fuel properties. Analytical techniques, including Fourier Transform Infrared Spectroscopy and Gas Chromatography-Mass Spectrometry, reveal promising chemical characteristics, with saturated, polyunsaturated, and monounsaturated components at 2.59%, 4.80%, and 92.61%, respectively. Aspen HYSYS simulation enhances the understanding of the entire biodiesel production process. Therefore, this study leverages Aspen HYSYS software for simulating the biodiesel production process while employing Response Surface Methodology (RSM) to optimize key process conditions. Additionally, the research assesses the effectiveness of micro membrane filtration in purifying biodiesel, offering valuable insights into its selectivity and permeability. These findings contribute to the development of sustainable and environmentally friendly fuel production practices, marking a significant stride towards cleaner energy alternatives. Sun, 04 Feb 2024 00:00:00 GMT https://repository.ju.edu.et//handle/123456789/9162 2024-02-04T00:00:00Z