Characterization and Optimization of Iron (III) Modified Bentonite Adsorbent for Efficient Removal of Fluoride from Aqueous Solution
| dc.contributor.advisor | Zebene, Kiflie (PhD) | |
| dc.contributor.author | Frehiwot, Tesfamariam | |
| dc.date.accessioned | 2018-12-22T05:11:00Z | |
| dc.date.accessioned | 2023-11-10T14:54:28Z | |
| dc.date.available | 2018-12-22T05:11:00Z | |
| dc.date.available | 2023-11-10T14:54:28Z | |
| dc.date.issued | 2018-06 | |
| dc.description.abstract | The main objective of the research was to prepare Fe iv 3+ -modified bentonite clay to be used as an adsorbent by optimizing the iron three loading through batch wise variation of agitation time, adsorbent dose, and iron three concentration for efficient removal of fluoride from aqueous solution. Physicochemical characterization of raw and Fe 3+ -modified bentonite clay was done by X-ray diffraction, Fourier transformed infrared spectroscopy, Cation exchange capacity, and pHpzc. To investigate the performance of the prepared Fe 3+ -modified bentonite adsorbent the effect of contact time, adsorbate concentration, adsorbent dosage and pH were evaluated. The adsorption capacity of fluoride by Fe 3+ -modified bentonite was observed to be 3.37 mg/g at (26±2) 0 C temperature. Design-Expert 7.0.0 three-level-full factorial RSM was applied for experimental design and statistical analysis of results. A total of 32 experiments were conducted at conditions of adsorbent dosage 1, 1.5 and 2 g, initial fluoride concentration 5, 15 and 25 ppm, and 15, 30 and 45 min of contact time. From the analysis of experimental results optimum conditions for efficient removal of fluoride were obtained at 2 g adsorbent dosage, 15 ppm adsorbate concentration and 15 min contact time which resulted 99.56% F - removal. Kinetic studies revealed that fluoride adsorption fitted well to pseudo-second-order model and Freundlich adsorption isotherm. Fe 3+ -modified bentonite showed a good stability in removing fluoride from natural fluoride containing water with > 66% F - removal. The fluoride loaded adsorbent was reused and also regenerated using 0.5 M NaOH. Thus, this study has proved that Fe 3+ -modified bentonite is a promising low cost adsorbent with high adsorption capacity of fluoride and can be a candidate for conventional de-fluoridation methods. | en_US |
| dc.identifier.uri | http://etd.aau.edu.et/handle/12345678/15275 | |
| dc.language.iso | en_US | en_US |
| dc.publisher | AAU | en_US |
| dc.subject | Adsorption | en_US |
| dc.subject | Batch experiments | en_US |
| dc.subject | Fluoride | en_US |
| dc.subject | Bentonite clay | en_US |
| dc.subject | Cation exchange capacity | en_US |
| dc.subject | Kinetics | en_US |
| dc.subject | Isotherm | en_US |
| dc.title | Characterization and Optimization of Iron (III) Modified Bentonite Adsorbent for Efficient Removal of Fluoride from Aqueous Solution | en_US |
| dc.type | Thesis | en_US |