Heavy oil fly ash "HOFA" is the fly ash generated in power stations using heavy oil as fuel. HOFA is considered a hazardous waste because it contains considerable amounts of heavy metals. However, it contains …
Along with the studies on Ga, potential extraction of vanadium from this fly ash was also investigated. Vanadium is commonly recovered from titaniferous magnetite ores and as V2 O5 from by-products of crude oil, being mainly used to produce high-strength and low-alloy steels [22]. Since 50:50% coal/petcoke blend is gasified in Puertollano IGCC ...
Recovery of vanadium and nickel from heavy oil fly ash (HOFA): a critical review. Cite this: RSC Adv., 2023, 13, 6327. Ashraf Bakkar, *a Mohamed M. El-Sayed …
Among the compounds of vanadium in the fly ash, vanadium pentoxide, V 2 O 5, and vanadic oxide, V 2 O 4, are slightly soluble in water but dissolve easily in acid and alkaline solutions (Abdel ...
According to the XRD analysis, vanadium in the petroleum-fly ash occurs mainly in the form of VOSO4·3H2O, and the existing form of nickel is identified as NiS2O6.6H2O. There are significant amounts of carbon, and certain amounts of MgSO4·6H2O and CaSO4. From the LECO analysis, the carbon content is 36.5 wt%, and sulphur content is 12.3 wt%.
The activation energy of the leaching reaction in the temperature range 25 to 65 °C was found to be 17.1 kJ mol −1. In this work, vanadium (V) was selectively extracted from fuel-oil fly ash using a leaching process utilizing organic acids extracted from lemon juice with assistance from ultrasound and H 2 O 2. Go to: 1. Introduction.
This study investigated the use of microwave-assisted leaching to recover the vanadium (V) and nickel (Ni) of fly ash collected from power plants. The fly ash sample was characterized using XRF, ICP-OES, powder X-ray diffraction, FESEM, and a laser particle size analyzer. The sample was found to be valuable as well as hazardous due to …
According to the XRD analysis, vanadium in the petroleum-fly ash occurs mainly in the form of VOSO 4 ·3H 2 O, and the existing form of nickel is identified as NiS 2 O 6 .6H 2 O. There are significant
Though vanadium recovery was not complete from oil fly ash (with a 70% recovery level), the proposed procedure allowed an efficient, simple and complete …
Valorization of fly ash by nickel ferrite and vanadium oxide recovery through pyro-hydrometallurgical processes: Technical and environmental assessment. A. Hamidi, S. …
The results of leaching fly ash in sodium hydroxide solutions of different concentrations is shown in Fig. 4.It can be seen that along with the increase in the concentration of sodium hydroxide, the pH of the leached EP fly ash increases from 8.7 to 12.9, and the extraction of vanadium increases from 2.6 to 45%.
Abstract. In order to reduce the environmental impact due to land disposal of oil fly ash from power plants and to valorize this waste material, the removal of vanadium was …
Coal fly ash (CFA), produced in coal-fired power plants, is categorized as hazardous waste and has caused serious environmental impacts. ... vanadium and lithium extraction from coal fly ash: sodium salts roasting and organic acids leaching. Fuel, 312 (2022), Article 122844, 10.1016/j.fuel.2021.122844. View PDF View article View in …
Along with the studies on Ga, potential extraction of vanadium from this fly ash was also investigated. Vanadium is commonly recovered from titaniferous magnetite ores and as V 2 O 5 from by-products of crude oil, being mainly used to produce high-strength and low-alloy steels [22]. Since 50:50% coal/petcoke blend is gasified in …
Vanadium and its compounds were widely used in many fields, it could be recycled and reused. The technology for recovery of vanadium from all vanadium-bearing resources should be developed. ... Vanadium recovery from oil fly ash by leaching, precipitation and solvent extraction processes. Waste Manag., 27 (2007), pp. 425-438. …
Among these secondary sources, oil fly ash contains up to 40 wt.% vanadium (V) in the form of V 2 O 5 (Navarro et al. 2007). In addition to the economic value of V recovery from oil fly ash, there ...
In Jordan, large amounts of fly ash (FA) are produced as a result of burning heavy fuel in power plants. Extraction of metals from FA is an important …
This study investigated the use of microwave-assisted leaching to recover the vanadium (V) and nickel (Ni) of fly ash collected from power plants. The fly ash sample was characterized using XRF, ICP-OES, powder X-ray diffraction, FESEM, and a laser particle size analyzer. The sample was found to be valuable as well as hazardous due to …
Solvent extraction of vanadium and aluminum from Na2CO3 leaching of oil fly ash (top) using Aliquat 336 and vanadium stripping with NH4Cl + NH3 (1.5 M) (bottom) (Experimental conditions: leaching: Na2CO3 (0.66 M), …
Hamster tracheal organ cultures were used to study the in vitro effects of vanadium and oil-fired fly ash on mucociliary respiratory epithelium. Two vanadium compounds, VOSO 4 and V 2 O 5, and fly ash from an oil-fueled power plant were dissolved or suspended in culture medium over a range of concentrations and epithelia …
Recovery of vanadium and nickel from an oil fly ash is studied in a two-step leaching process, carried out under ambient pressure without calcination. In the leaching, nickel is dissolved with NH 4 Cl in the first step, followed by vanadium leaching with Na 2 CO 3 in the second step. Both leachants depress the dissolution of iron and aluminium …
The recovery of vanadium from heavy oil fly ash having a high carbon content was performed using a four-step process consisting of a preliminary burning in order to reduce the carbonaceous fraction, followed by an acid leaching and an oxidative precipitation of vanadium pentoxide. The preliminary burning was conducted in the …
The study proposed a closed-loop flowsheet for fly ash recycling. • NiFe 2 O 4, V 2 O 5, and cementitious materials were recovered from fly ash.. Selective inorganic acid leaching became possible due to the formation of NiFe 2 O 4.. Recycled NiFe 2 O 4 from fly ash showed excellent magnetic properties.. LCA study conducted on the …
Abstract. The Puertollano Integrated Coal Gasification Combined Cycle (IGCC) Power Plant (Spain) fly ash is characterized by a relatively high content of Ga and V, which occurs mainly as Ga2O3 and ...
The salt roasting treatment is found to improve vanadium recovery significantly when the fly ash is fully oxidized. This is easily achieved by burning off the carbon present in the "as received" fly ash under excess air. The basic leaching used in the new process selectively dissolves vanadium from the roasted ash, leaving nickel and ...
Among the compounds of vanadium in the fly ash, vanadium pentoxide, V 2 O 5, and vanadic oxide, V 2 O 4, are slightly soluble in water but dissolve easily in acid and alkaline solutions (Abdel ...
The compositions of five main metal elements (vanadium, iron, nickel, sodium, and magnesium) in fly ash samples are shown in Table 1pared to the FA-H 2 SO 4 which shows declination in all the elements after leaching, the NaOH exhibits a strong selectivity of vanadium element in FA-NaOH, indicating that the leaching behavior of …
Among the compounds of vanadium in the fly ash, vanadium pentoxide, V 2 O 5, and vanadic oxide, V 2 O 4, are slightly soluble in water but dissolve easily in acid and alkaline solutions (Abdel-latif, 2002). Nickel is an important metal applied in many fields, such as energy materials and functional materials, chemicals and catalysts, cathodes ...
Vanadium amount increased from 16.2 in ash to 41.4–48.1 V 2 O 5 wt% in slag. The solubility of vanadium was studied during aqueous leaching and in solutions of H 2 SO 4 and Na 2 CO 3. ... The use of fly ash and Crepidula shells in addition to gravel wash mud provides high silica and calcium contents, which both react with clay, leading …
1.. IntroductionThe power generation industry that uses heavy oil (Venezuelan oil for example) produces a solid residue called flyash that contains a relatively high heavy metal content, particularly vanadium oxide (typically 3% V 2 O 5) and nickel oxide (about 1% NiO).In addition, and in order to meet strict NO x specifications during burning, the …