http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Aqueous processing of nickel spent catalyst for a value added product
Abdul Rauf Sheik,Malay Kumar Ghosh,Kali Sanjay,Tondepu Subbaiah,Barada Kanta Mishra,Abdullahi Aalafara Baba 한국화학공학회 2013 Korean Journal of Chemical Engineering Vol.30 No.2
Nickel was recovered from a fertilizer industry spent catalyst by leaching with nitric acid followed by nickel hydroxide precipitation. The optimization of temperature, initial acid concentration and particle size for leaching of the spent catalyst was done through 23 factorial design. A maximum extraction of 91.9% was achieved at 90 oC, 1.5M HNO3 and 62.5 μm particle size. Temperature and acid concentration showed positive effect, while particle size showed no effect. A regression equation was developed and employed to predict conditions for 100% extraction which were experimentally tested. Nickel hydroxide was electrochemically precipitated from the leach liquor and its maximum discharge capacity was found to be 155 mAh/g. A 3-stage counter current leaching circuit was designed to obtain a leach liquor of suitable pH. XRD characterization of the precipitated Ni(OH)2 shows to consist of both α- and β-forms.
Bio-hydrometallurgical processing of low grade chalcopyrite for the recovery of copper metal
Sandeep Panda,Lala Behari Sukla,Chinmaya Kumar Sarangi,Nilotpala Pradhan,Tondepu Subbaiah,Barada Kanta Mishra,Gur Lal Bhatoa,Mullukutlashivram Prasad,Subrat Kumar Ray 한국화학공학회 2012 Korean Journal of Chemical Engineering Vol.29 No.6
A process flowsheet was developed to recover copper metal from the lean sulfide ore of copper available at Malanjkhand, Hindustan Copper Limited (HCL), India. Copper pregnant leach solution (PLS) obtained from bio-heap leaching of chalcopyrite containing 0.3% copper was purified through solvent extraction (SX) and the copper recovered by electrowinning (EW). The copper-free raffinate obtained from SX stripping unit was returned back to the bioleaching circuit. The purity of the electrolytic copper produced at pilot scale was found to be 99.96%. During electrowinning,the effect of flow rate of electrolyte on current efficiency and energy consumption was also studied.
Recovery of copper values from bio-heap leaching of low grade Malanjkhand chalcopyrite ore
Lala Behari Sukla,Kailash Chandra Nathsarma,Joystna Rani Mahanta,Sradhanjali Singh,Snehasis Behera,Karanam Srinivas Rao,Tondepu Subbaiah,Barada Kanta Mishra 한국화학공학회 2009 Korean Journal of Chemical Engineering Vol.26 No.6
M/S Hindustan Copper Limited (HCL), India generates large amounts of lean sulfide ores of copper. The current production of lean copper ores in India is 0.55 million tons with ~0.3% average copper content. Heap-bioleaching of the lean copper ores in 15 and 30 ton scales was undertaken at IMMT, Bhubaneswar. The leaching study showed 0.09% dissolution of copper from the ore body per day. The leach liquor was processed through solvent extraction and electrowinning. Extraction of copper from the actual leach liquor was carried out with 1.5% LIX 622N in kerosene with zero co-extraction of iron. The copper-free raffinate was fed back to the leaching unit. Stripping of copper from the loaded organic was carried out with 180 kg/㎥ H2SO4. The copper pregnant electrolyte was passed through a carbon column to make it free from entrained organic and was fed to the electrowinning unit. The increase in current efficiency was due to the increase in the concentration of electrolyte. The energy consumption was 1.7 kWh/kg at a flow rate of 4.5 L/h. Smooth and bright sheets of copper of 99.99% purity were obtained.
Sandeep Panda,Pradeep Chandra Rout,Chinmaya Kumar Sarangi,Srabani Mishra,Nilotpala Pradhan,Umaballav Mohapatra,Tondepu Subbaiah,Lala Behari Sukla,Barada Kanta Mishra 한국화학공학회 2014 Korean Journal of Chemical Engineering Vol.31 No.3
Bioleaching studies for chalcopyrite contained ball mill spillages are very scarce in the literature. We developeda process flow sheet for the recovery of copper metal from surface activated (600 oC, 15 min) ball mill spillagethrough bio-hydrometallurgical processing route. Bioleaching of the activated sample using a mixed meso-acidophilicbacterial consortium predominantly A. ferrooxidans strains was found to be effective at a lixiviant flow rate of1.5 L/h, enabling a maximum 72.36% copper recovery in 20 days. Mineralogical as well as morphological changesover the sample surface were seen to trigger the bioleaching efficiency of meso-acidophiles, thereby contributing towardsan enhanced copper recovery from the ball mill spillage. The bio-leach liquor containing 1.84 g/L Cu was purified throughsolvent extraction using LIX 84I in kerosene prior to the recovery of copper metal by electrowinning. Purity of thecopper produced through this process was 99.99%.