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https://ptsldigital.ukm.my/jspui/handle/123456789/487272Full metadata record
| DC Field | Value | Language |
|---|---|---|
| dc.contributor.advisor | Zahira Yaakob, Prof. Ir. Dr. | - |
| dc.contributor.author | Ahmed M. Bshish (P46835) | - |
| dc.date.accessioned | 2023-10-11T02:31:43Z | - |
| dc.date.available | 2023-10-11T02:31:43Z | - |
| dc.date.issued | 2014-03-20 | - |
| dc.identifier.other | ukmvital:74857 | - |
| dc.identifier.uri | https://ptsldigital.ukm.my/jspui/handle/123456789/487272 | - |
| dc.description | Hydrogen production by steam reforming of ethanol is an interesting choice since ethanol can be produced from renewable sources. There is no agreement on the most suitable catalytic system for hydrogen production via ethanol steam reforming. Hence, the work to develop an active and selective catalytic system for this application is still in progress. Thus, the aim of this work is firstly to carry out a complete thermodynamic analysis to understand the effect of operating conditions on ethanol conversion and gaseous products. Then, attention was paid to developing a high performance catalyst system for production of hydrogen via ethanol steam reforming, and also on developing an integrated system capable of predicting H2 yield using artificial neural network (ANN) model. Therefore, a thermodynamic equilibrium analysis was performed over the following variable ranges: pressure 1-50 atm, temperature 300-900 K, and water-to-ethanol feed ratio 3:1-12:1. A catalyst study was performed to investigate the performance of nickel as an active metal, supported on γ-Al2O3. Two series of catalysts with various Ni loadings (6, 8, 10, 12, and 20 wt%) were prepared by impregnation and precipitation methods and were tested in ethanol reforming reaction. The catalysts were characterized by BET, XRD, TPR, and SEM-EDAX. The result showed that lower Ni loading catalysts were more efficient in H2 production, as evidenced by the finding that a 6 wt% Ni catalyst, synthesized via the precipitation method, yielded 3.68 mol H2 per mol ethanol fed. Moreover, sol gel made alumina supports prepared for nickel catalysts were calcined at different temperatures. A series of sol gel made alumina support catalysts were synthesized by an impregnation procedure. The nickel content in all samples was fixed at 6 wt %. These catalysts were characterized by BET, XRD, TPR, TPD, and CHNS elemental analysis. The influence of varying the calcination temperature of the sol gel made supports on catalyst activity was tested. The result showed that, the structure of the sol gel made alumina supports was transformed in the order of γ → (γ + θ) → θ- alumina as the calcination temperature of the supports increased from 600°C to 1000 °C. Both hydrogen yield and ethanol conversion presented a volcano-shaped behaviorwith maximum values of 4.3 mol/mol ethanol fed and 99.5%, respectively. The highest performance was exhibited over a catalyst calcined at 800°C which may be attributed to the strong interaction of Ni species and sol gel made alumina that led to high nickel dispersion and small particle size. Statistical approach using response surface methodology (RSM) and central composite design (CCD) was employed to optimize the process variables. The optimal conditions were obtained at a temperature of 500 °C, a water-ethanol molar ratio of 20, and liquid hourly space velocity (LHSV) of 0.72 h-1. These optimal conditions resulted in a hydrogen yield of 4.7 mol/mol of ethanol fed, an ethanol gasification of 85%, and a CO yield of 0.25 mol/mol of ethanol fed. Finally, a multi-layer ANN model was examined and trained to predict H2 yield, CO yield, and ethanol conversion. The study considered the effect of temperature, water-ethanol molar ratio, and LHSV as ANN inputs on hydrogen yield, ethanol gasification, and CO yield as outputs. The performance of the ANN model has verified and demonstrated effectiveness with a significant efficiency of 0.91, 0.84, and 0.95 for H2, CO, and ethanol, respectively. In conclusion, this research has achieved its stated goal of developing a catalyst system for ethanol steam reforming reaction capable of maximizing hydrogen yield.,PhD | - |
| dc.language.iso | eng | - |
| dc.publisher | UKM, Bangi | - |
| dc.relation | Faculty of Engineering and Built Environment / Fakulti Kejuruteraan dan Alam Bina | - |
| dc.rights | UKM | - |
| dc.subject | Hydrogen production | - |
| dc.subject | Ethanol steam | - |
| dc.subject | Ni/Al₂O₃ catalyst | - |
| dc.subject | Universiti Kebangsaan Malaysia -- Dissertations | - |
| dc.title | Hydrogen production by ethanol steam reforming using Ni/Al₂O₃ catalyst | - |
| dc.type | Theses | - |
| dc.format.pages | 239 | - |
| Appears in Collections: | Faculty of Engineering and Built Environment / Fakulti Kejuruteraan dan Alam Bina | |
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| File | Description | Size | Format | |
|---|---|---|---|---|
| ukmvital_74857+Source01+Source010.PDF Restricted Access | 9.72 MB | Adobe PDF |  View/Open |
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