14425

13036

فرآوري مواد معدني

1397

چهارده، 104ص.: مصور، جدول، نمودار

علي احمدي عامله

داور داخلي: مهدي نصيري; داور خارجي: كيومرث زرگوش

1397/12/08

معدن

1397/12/13

ID13036

Bioleaching of a mixture of electronic wastes and sulphidic tailings in a continuous system Seifollah Akbari Mishani Email Address Akbariseifallah@gmail com January 2019 Department of Mining Engineering Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language PersianSupervisor Ali Ahmadi a ahmadi@cc iut ac irAbstract The extraction of copper from a mixture of a Cu Ni Co bearing sulphidic tailing and printed circuit boards PCBs was investigated by bioleaching process followed by solvent extraction of the pregnant leach solutions PLS Bioleaching was conducted in both batch and continuous modes in 2 and 50 L stirred tank bioreactors STBRs using a mixed culture of iron and sulphur oxidizing moderately thermophilic microorganisms such asacidithiubacillus caldus Leptospirillum ferriphilum Sulfobacillus thermosulfidooxans and Ferroplasma Bioleaching was firstly carried out in a 2 L STBR at the pulp density of 10 w v mass ratio of PCB to sulfidictailings of 1 to 4 Norris nutrient medium 15 v v bacteria cultivation at 45 C and about 87 3 of the copperwas leached Bioleaching was also conducted in three 50 L STBRs in the same conidition with 2 L STRB and infirst reactor 89 6 70 7 and 42 3 and in second reactor 92 8 65 1 and 45 4 and in third reactor 92 4 67 and 42 4 copper zinc and aluminum was extracted The process was then performed in the continuousmode in which 95 of copper was extracted Afterward the PLS which contained 2 85 g l Cu was purified bysolvent extraction with LIX 984N extractant diluted in kerosene In this regards the effect of some criticalparameters namely extraction time pH of the aqueous feed stirring rate A aqueous O organic phase ratio andextractant concentration on the extraction efficiency of copper was investigated Results showed that copper canbe efficiently separated from the PLS in two stages with minimum co extraction Keywords Electronic Waste Printed Circuit Boards Sulphidic Tailings Bioleaching SolventExtraction Copper

علي احمدي عامله

داور داخلي: مهدي نصيري; داور خارجي: كيومرث زرگوش