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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.
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.
Smaranika Mohapatra,Chandan Sengupta,Bansi Dhar Nayak,Lala Bihari Sukla,Barada Kanta Mishra 한국화학공학회 2008 Korean Journal of Chemical Engineering Vol.25 No.5
Experimental investigation made previously on microbiological leaching of nickel and cobalt from the laterite nickel ore of Sukinda Valley reveals that the recovery was not very much promising under any favorable conditions. Therefore, in order to improve the efficiency for bioleaching, the homogenized lateritic ore in palletized form is thermally pretreated by roasting at different temperatures. The parameters studied for the bioleaching experiments were the four types of pretreated ore which were roasted at different temperatures, i.e., 300 oC, 400 oC, 600 oC and 800 oC, in shake flask by using a mixed mesophilic acidophilic bacterial consortium consisting predominantly of the Acidithiobacillus ferrooxidans strain. It was observed that the pretreated ore at 600 oC with 10% (w/v) pulp density showed maximum recovery of nickel and cobalt, i.e., 59.18% (4.556 ppm) and 65.09% (0.546 ppm), using 10% (v/v) (2.5×108 cells/ ml) consortium concentration at 1.5 pH, 30 oC, and 150 rpm after an incubation period of 31 days.
( Manoranjan Nayak ),( Swagat S Rath ),( Manikkannan Thirunavoukkarasu ),( Prasanna K Panda ),( Barada K Mishra ),( Rama C Mohanty ) 한국미생물 · 생명공학회 2013 Journal of microbiology and biotechnology Vol.23 No.9
A series of experiments were carried out with three native strains of microalgae to measure growth rates, biomass, and lipid productivities. Scenedesmus sp. IMMTCC-6 had better biomass growth rate and higher lipid production. The growth, lipid accumulation, and carbon dioxide (CO2) consumption rate of Scenedesmus sp. IMMTCC-6 were tested under different NaOH concentrations in modified BBM. The algal strain showed the maximum specific growth rate (0.474/day), biomass productivity (110.9 mg l-1d-1), and CO2 consumption rate (208.4 mg l-1d-1) with an NaOH concentration of 0.005 M on the 8th day of cultivation. These values were 2.03-, 6.89-, and 6.88-fold more than the algal cultures grown in control conditions (having no NaOH and CO2). The CO2 fixing efficiency of the microalga with other alternative carbon sources like Na2CO3 and NaHCO3 was also investigated and compared. The optimized experimental parameters at shake-flask scale were implemented for scaling up the process in a self-engineered photobioreactor. A significant increase in lipid accumulation (14.23% to 31.74%) by the algal strain from the logarithmic to stationary phases was obtained. The algal lipids were mainly composed of C16/C18 fatty acids, and are desirable for biodiesel production. The study suggests that microalga Scenedesmus sp. IMMTCC-6 is an efficient strain for biodiesel production and CO2 biofixation using stripping solution of NaOH in a cyclic process.
Biological leaching of nickel and cobalt from lateritic nickel ore of Sukinda mines
Smaranika Mohapatra,Chandan Sengupta,Bansi Dhar Nayak,Lala Bihari Sukla,Barada Kanta Mishra 한국화학공학회 2009 Korean Journal of Chemical Engineering Vol.26 No.1
In the present study lateritic nickel ore was used for bacterial leaching using a mixed consortium of mesophilic acidophiles. The microorganisms were adapted to 1 gram nickel/L prior to leaching. For the experiments, lateritic ore in different forms such as raw, roasted, roasted ore presoaked in dilute sulphuric acid and palletized pretreated roasted (400℃ and 600℃) ore were taken. The leaching experiments were conducted in 9 K+ with 40 L capacity bioreactor using 10% (v/v) inoculum concentration at 10% (w/v) pulp density. The aeration was maintained at 2-3 L/min and the speed of agitator and temperature at 400-500 rpm and 35℃. The maximum extraction of nickel and cobalt was observed with pretreated ore (600℃) at 10% pulp density (77.23% and 73.22%) respectively within 31 days at pH 1.5 and least extraction in case of raw ore i.e., 9.47% nickel and 41.12% cobalt respectively.
( Jaya Shree Jena ),( Nilotpala Pradhan ),( Rati Ranjan Nayak ),( Bishnu P Dash ),( Lala Behari Sukla ),( Prasanna K Panda ),( Barada K Mishra ) 한국미생물 · 생명공학회 2014 Journal of microbiology and biotechnology Vol.24 No.4
Bionanotechnology has revolutionized nanomaterial synthesis by providing a green synthetic platform using biological systems. Among such biological systems, microalgae have tremendous potential to take up metal ions and produce nanoparticles by a detoxification process. The present study explores the intracellular and extracellular biogenic syntheses of silver nanoparticles (SNPs) using the unicellular green microalga Scenedesmus sp. Biosynthesized SNPs were characterized by AAS, UV-Vis spectroscopy, TEM, XRD, FTIR, DLS, and TGA studies and finally checked for antibacterial activity. Intracellular nanoparticle biosynthesis was initiated by a high rate of Ag+ ion accumulation in the microalgal biomass and subsequent formation of spherical crystalline SNPs (average size, 15-20 nm) due to the biochemical reduction of Ag+ ions. The synthesized nanoparticles were intracellular, as confirmed by the UV-Vis spectra of the outside medium. Furthermore, extracellular synthesis using boiled extract showed the formation of well scattered, highly stable, spherical SNPs with an average size of 5-10 nm. The size and morphology of the nanoparticles were confirmed by TEM. The crystalline nature of the SNPs was evident from the diffraction peaks of XRD and bright circular ring pattern of SAED. FTIR and UV-Vis spectra showed that biomolecules, proteins and peptides, are mainly responsible for the formation and stabilization of SNPs. Furthermore, the synthesized nanoparticles exhibited high antimicrobial activity against pathogenic gram-negative and gram-positive bacteria. Use of such a microalgal system provides a simple, cost-effective alternative template for the biosynthesis of nanomaterials in a large-scale system that could be of great use in biomedical applications.
Sandeep Panda,Srabani Mishra,Danda Srinivas Rao,Nilotpala Pradhan,Umaballava Mohapatra,Shivakumar Angadi,Barada Kanta Mishra 한국화학공학회 2015 Korean Journal of Chemical Engineering Vol.32 No.4
Copper slag was subjected to in-depth mineralogical characterization by integrated instrumental techniquesand evaluated for the efficacy of physical beneficiation and mixed meso-acidophilic bioleaching tests towardsrecovery of copper. Point-to-point mineral chemistry of the copper slag is discussed in detail to give better insight intothe association of copper in slag. Characterization studies of the representative sample revealed the presence of fayaliteand magnetite along with metallic copper disseminated within the iron and silicate phases. Physical beneficiation of thefeed slag (~0.6% Cu) in a 2 L working volume flotation cell using sodium isopropyl xanthate resulted in Cu beneficiationup to 2-4% and final recovery within 42-46%. On the other hand, a mixed meso-acidophilic bacterial consortiumcomprised of a group of iron and/or sulfur oxidizing bacteria resulted in enhanced recovery of Cu (~92-96%) from theslag sample. SEM characterization of the bioleached slag residue also showed massive coagulated texture with severeweathered structures. FE-SEM elemental mapping with EDS analysis indicated that the bioleached residues were devoidof copper.
Percolation bacterial leaching of low-grade chalcopyrite using acidophilic microorganisms
Karanam Srinivasa Rao,Amrita Mishra,Devbrata Pradhan,Gautam Roy Chaudhury,Birendra Kumar Mohapatra,Trupti Das,Lala Bihari Sukla,Barada Kanta Mishra 한국화학공학회 2008 Korean Journal of Chemical Engineering Vol.25 No.3
Bioleaching studies were carried out in percolation columns using low-grade copper containing rock (granite). The lixiviant consisted of acidified ferric sulfate containing acidophilic microorganisms. The iron oxidizing strain was isolated from Malanjkhand mine water and after adaptation the iron oxidation observed to be 500 mg/L/h. Leaching parameters studied were lixiviant flow rate, particle size and bed height. It was observed that leaching efficiency increased with decrease of particle size and lixiviant flow rate. The precipitation of iron during leaching observed to be low as pH was maintained at 2. Based on the leaching kinetics, a unified rate equation was developed and shown as ra(dp)[−0.61 (F)−0.76 (Hb)0.97.]수식
Lala Behari Sukla,Sunil Kumar Behera,Prangya Parimita Panda,Sandeep Kumar Saini,Nilotpala Pradhan,Barada Kanta Mishra 한국화학공학회 2013 Korean Journal of Chemical Engineering Vol.30 No.2
Oxalic acid is a prominent metabolite secreted by several fungi under specific conditions, which acts as a metal chelating agent. Amongst different fungal species, Aspergillus niger is favored as the best option for microbial production of oxalic acid. The present study deals with the oxalic acid over production by A. niger in response to manganese supplement to its growth medium, which in turn improves the recovery of nickel from pre-treated chromite overburden(COB) during fungal bioleaching. The metabolic pathway in oxalate bio-synthesis by A. niger involves one prominent cytoplasmic enzyme oxaloacetate acetylhydrolase (OAH), which catalyzes the breakdown of oxaloacetate metabolic intermediate to oxalate and acetate. Oxalic acid production was increased due to supplement of manganese to the culture medium of the A. niger. Manganese acts as cofactor for OAH enzyme; further, it enhances the catalytic activity of OAH to produce more oxalate. With oxalic acid production by A. niger, nickel recovery from pre-treated COB was improved. During the study, a maximum of nickel recovery was achieved up to 38.6% from pre-treated COB by adding 80 ppm of manganese to the culture media, whereas 24.0% of nickel was recovered without supplement of manganese (experiments were performed at 30 oC and the COB pulp density 2% w/v).