title: Bioleaching of tungsten-rich spent hydrocracking catalyst using Penicillium simplicissimum.
abstract: Adaptation of Penicillium simplicissimum with different heavy metals present in a spent hydrocracking catalyst, as well as one-step, two-step, and spent medium bioleaching of the spent catalyst by the adapted fungus, was examined in batch cultures. Adaptation experiments with the single metal ions Ni, Mo, Fe, and W showed that the fungus could tolerate up to 1500 mg/L Ni, 8000 mg/L Mo, 3000 mg/L Fe, and 8000 mg/L W. In the presence of multi-metals, the fungus was able to tolerate up to 300 mg/L Ni, 200 mg/L Mo, 150 mg/L Fe and 2500 mg/L W. A total of 3% (w/v) spent catalyst generally gave the maximum extraction yields in the two-step bioleaching process (100% of W, 100% of Fe, 92.7% of Mo, 66.43% of Ni, and 25% of Al). The main lixiviant in the bioleaching was shown to be gluconic acid. The red pigment produced by the fungus could also possibly act as an agent in Al leaching.
authors.affiliation: Department of Chemical and Petroleum Engineering, Center of Excellence, Development and Strategic Plants for Bioprocess Technology, Sharif University of Technology, Tehran, Iran.
authors.forename: F
authors.initials: F
authors.lastname: Amiri
authors.forename: S
authors.initials: S
authors.lastname: Yaghmaei
authors.forename: S M
authors.initials: SM
authors.lastname: Mousavi
mesh_terms: D001673:Biodegradation, Environmental / Q000187:drug effects; D018533:Biomass; D002384:Catalysis / Q000187:drug effects; D004785:Environmental Pollutants / Q000302:isolation & purification*; D006863:Hydrogen-Ion Concentration / Q000187:drug effects; D007220:Industrial Waste / Q000032:analysis*; D010407:Penicillium / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D059027:Recycling; D014414:Tungsten / Q000302:isolation & purification* / Q000633:toxicity
chemical_list: D004785:Environmental Pollutants; D007220:Industrial Waste; D014414:Tungsten