Master Degree / Yüksek Lisans Tezleri

Permanent URI for this collectionhttps://hdl.handle.net/11147/3008

Browse

Filters

2017 - 201912020 - 20231

Settings

Department: search.filters.department.Thesis (Master)--İzmir Institute of Technology, Chemical EngineeringSubject: search.filters.subject.Biofuels

Search Results

Now showing 1 - 2 of 2
  • Master Thesis
    Valorization of Biomass for Fuel and Chemicals Production
    (01. Izmir Institute of Technology, 2023) Yüksel Özşen, Aslı; Yüksel Özşen, Aslı; 03.02. Department of Chemical Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology
    Rapidly increasing global energy demand resulting from the growing population and worldwide development increased consumption of limited fossil fuel usage that causes severe environmental deterioration by CO2 emission have sparked interest in finding green, renewable, and sustainable alternative sources for energy. Bio-oil, derived by several biomass via liquefaction, is a promising candidate to replace fossil fuels. Turkey is a country, 27% of which is covered with forests (mostly oak trees). Therefore, it has great potential for cheap lignocellulosic feedstock forest residues from industrial applications and harvesting. In the present study, the thermal liquefaction of oak wood particles (OWP) was performed using various solvents besides water, such as ethanol, 1-butanol, and 1,4-dioxane. The experiments were carried out in a batch reactor for 1 and 2 h residence time at different temperatures (210oC, 240oC, and 270oC). Bio-oil samples obtained at best reaction temperature, 270oC, optimum residence time, 1 h, were analyzed with TGA, CHNS elemental analyzer, FTIR, and GC-MS. Based on energy recovery calculations, the enhancement of pristine OWP's energy efficiency depends on bio-oil yield, and quality was confirmed for all solvent types. 1,4-dioxane showed the best performance in yielding the maximum bio-oil with 51.8%. The higher heating values of the bio-oils ranged from 22.1 to 35 MJ/kg. Phenolic groups were the predominant components of bio-oil produced from OWP, while intensity of alcohols, ketones, and acids varied based on using solvents.
  • Master Thesis
    Biofuels Production Using Canola Oil Over Heterogeneous Catalysts
    (Izmir Institute of Technology, 2017) Özdoğru, Bertan; Şeker, Erol; Şeker, Erol; 03.02. Department of Chemical Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology
    The goal of this study was to investigate the activity of Ni loaded on Al2O3-SiO2 supports prepared with different acids for the production of biofuel grade compounds while using canola oil as our feedstock. While keeping the reaction conditions constant, catalyst preparation parameters such as aluminum concentration, nickel concentration, calcination temperature, and acid types investigated with statistical methods by constructing Box Behnken design using three continuous parameters with two levels and one categorical parameter with three level. Responses considered in this study were aldehyde, ester, organic acid and other compound yields calculated from the GC-MS analysis. After ANOVA analysis, empirical models calculated from this analysis used to optimize the catalyst preparation parameters. Three catalysts, one for each acid type, selected to investigate the validity of our model. Analysis did on these catalysts have shown that both 0% Ni/25% Al2O3-75% SiO2 w/H2SO4 at 900oC and 20% Ni/75% Al2O3-25% SiO2 w/H3PO4 at 900oC catalysts gave good ester yields with good organic acid utilization. 20% Ni/75% Al2O3-25% SiO2 w/H3PO4 at 900oC catalyst was exceptional in ester selectivity aspect while 0% Ni/25% Al2O3-75% SiO2 w/H2SO4 at 900oC catalyst was in organic acid utilization aspect. Presence of aluminum phosphate crystal phase observed with XRD resulted in 20% Ni/75% Al2O3-25% SiO2 w/H3PO4 at 900oC catalyst having the highest selectivity towards ester production. Combination of weak and strong acid sites increased the organic acid selectivity while lowering the selectivity towards esters for 0% Ni/25% Al2O3-75% SiO2 w/H2SO4 at 900oC catalyst. From the low organic acid utilization observed with 10% Ni/25% Al2O3-75% SiO2 w/HNO3 at 500oC and, 10% Ni/50% Al2O3-50% SiO2 w/H2SO4 at 700oC catalysts which had high amounts of weak acid sites, it could be said that organic acids can only be reacted over strong acid sites.