Sulfuric acid baking and leaching of spent Co-Mo/Al2O3 catalyst

Processing of spent platinum-based catalysts via fusion with potassium hydrogenosulfate

“…Based on the stoichiometry 1Al 3+ = 1Al(OH) 3 . This result is comparable to literature data [18,[25][26][27]33]. However, in this study, lower amounts of strong base (KOH) and water were necessary to precipitate soluble aluminium.…”

“…However some remarks were made: (i) the process is high-energy consuming. A study on the optimization of experimental parameters should be performed [26]; (ii) the final effluent is very saline and was generated in considerable quantities [27]; (iii) the excess of flux was entirely lost in the final effluent [27,28]. Based on these remarks the main improvements in the acid fusion process are: (i) to reduce the energy consumption; (ii) to recover at least partially the flux present in the final effluent.…”

Kinetics and statistical behavior of metals dissolution from spent petroleum catalyst using acidophilic iron oxidizing bacteria

“…In the combination process, the waste material was roasted either alone or in presence of acid or alkali. The roasted mass was subjected to leaching process by addition of suitable lixiviant such as acid or alkali [10,11]. Due to several drawbacks of the conventional techniques described above, biotechnological leaching processes have been developed as a potential alternative.…”

Up-gradation of MoO3 and separation of copper, iron, zinc from roasted molybdenum ore by a leaching process

“…The soda ash roasting process is another methodology developed and reported for a secondary source of molybdenum (Kar et al, 2004). At low temperatures (200-450 °C), the method established for the leaching process for spent Co-Mo/Al 2 O 3 catalyst was sulfuric acid baking (Kim et al, 2009). Thiophosphinic acid was proposed as a promising and selective extractants for recovery of the molybdenum from low grade ores (Archana et al, 1996).…”