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Microbial Leaching of Metals from Solid Industrial Wastes
Mishra, Debaraj,Rhee, Young Ha 한국미생물학회 2014 The journal of microbiology Vol.52 No.1
Biotechnological applications for metal recovery have played a greater role in recovery of valuable metals from low grade sulfide minerals from the beginning of the middle era till the end of the twentieth century. With depletion of ore/minerals and implementation of stricter environmental rules, microbiological applications for metal recovery have been shifted towards solid industrial wastes. Due to certain restrictions in conventional processes, use of microbes has garnered increased attention. The process is environmentally-friendly, economical and cost-effective. The major microorganisms in recovery of heavy metals are acidophiles that thrive at acidic pH ranging from 2.0-4.0. These microbes aid in dissolving metals by secreting inorganic and organic acids into aqueous media. Some of the well-known acidophilic bacteria such as Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans, Leptospirillum ferrooxidans and Sulfolobus spp. are well-studied for bioleaching activity, whereas, fungal species like Penicillium spp. and Aspergillus niger have been thoroughly studied for the same process. This mini-review focuses on the acidophilic microbial diversity and application of those microorganisms toward solid industrial wastes.
( Debaraj Mishra ),( Sun Hee Lee ),( Jae Hee Kim ),( Dong Jin Kim ),( Young Ha Rhee ) 한국환경생물학회 2011 환경생물 : 환경생물학회지 Vol.29 No.4
Bacterial diversity based on the denaturing gradient gel electrophoresis (DGGE) analysis of PCR amplified 16S rRNA gene sequences was determined for soil samples from two abandoned mine sites and the corresponding enrichment cultures using soil sample as key inoculum. Sequencing analysis of DGGE bands obtained from both the soil samples matched mostly with sequences of uncultured and newly described organisms, or organisms recently associated with the acid mine drainage environment. However, the enrichment of soil samples in ferrous sulfate and elemental sulfur media yielded sequences that were consistent with well known iron and sulfur oxidizing acidophilic bacteria. Analysis of enrichment cultures of soil samples from Dalsung mine revealed abundant γ Proteobacteria, whereas that of Gubong mine sample displayed acidophilic groups of γ Proteobacteria, α Proteobacteria, Actinobacteria and Firmicutes. Chemical elemental analysis of the mine samples indicated that the Dalsung site contained more iron and sulfate along with other toxic components as compared with those of the Gubong site. Biogeochemistry was believed to be the primary control on the acidophilic bacterial group in the enrichment samples.
김홍인,이기웅,Debaraj Mishra,이강명,홍정희,전민기,박해경 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.21 No.1
Alamine-336, diluted with kerosene and iso-decanol, was used for separation of vanadium (IV) andmolybdenum (VI) from leached solution generated by oxalic acid washing of spent residuehydrodesulfurization (RHDS) catalyst. The variation of aqueous pH represented that there was completeextraction of both vanadium (IV) and molybdenum (VI) at equilibrium pH 3.8. Both metals wereextracted by two stages counter current process using 10% Alamine-336 along with 5% iso-decanol atorganic to aqueous phase ratio 1:2. The metal loaded organic was then used for selective stripping ofeach metal. About 99% of vanadium (IV) and molybdenum (VI) was selectively stripped with 1.5 Msulfuric acid and 2 M ammonia solution, respectively. Both stripped solutions can be further processedfor the preparation of respective oxide components of vanadium and molybdenum.
김동진,안종관,Mishra, Debaraj,Kim, Dong-Jin,Ahn, Jong-Gwan,Ralph, David E. 한국자원리싸이클링학회 2008 資源 리싸이클링 Vol.17 No.2
혼합 호산성 박테리아를 이용하여 리튬이온 밧데리 산업 폐기물로부터 코발트와 리튬의 침출을 연구하였다. 혼합 호산성 박테리아의 성장기질은 단체 황 및 2가 철이온으로 구성되어 있으며 미생물에 의한 금속의 침출은 폐기물에 존재하는 금속과 황산이온의 양자 반응 때문에 일어난다. 본 연구에서 12일간 미생물 침출반응시 고상 폐기물중 코발트의 80%, 리튬의 20%가 용해되었으며 고액비가 높을수록 금속의 독성으로 인하여 미생물의 성장은 억제된다. 단체 황의 농도가 높을 조건에서는 일부 황 분말이 용해되지 않으며 금속의 침출속도는 황의 증가에 따라 감소한다. Mixed acidophilic bacteria were approached for leaching of cobalt and lithium from wastes of lithium ion battery industries. The growth substrates for the mixed mesophilic bacteria are elemental sulfur and ferrous ion. Bioleaching of the metal was due to the protonic action of sulfate ion on the metals present in the waste. It was investigated that bioleaching of cobalt was faster than lithium. Bacterial action could leach out about 80 % of cobalt and 20 % of lithium from the solid wastes within 12 days of the experimental period. Higher solid/liquid ratio was found to be detrimental for bacterial growth due to the toxic nature of the metals. At high elemental sulfur concentration, the sulfur powder was observed to be in undissolved form and hence the leaching rate also decreased with increase of sulfur amount.
Reactive Behavior of Ferrihydrite and Aluminic Ferrihydrite Toward the Adsorption of Arsenate
Mohapatra, Debasish,Mishra, Debaraj,Chaudhury, G. Roy,Das, R.P.,Park, Kyung-Ho 한국암반공학회 2006 Geosystem engineering Vol.9 No.2
The adsorption of arsenate (As(V)) on "ferrihydrite" prepared by two different methods; "aluminic ferrihydrite" (Fe(III)/ AI(III) molar ratio 1:1) and the stability of As(V) bearing materials were investigated. The parameters optimized for adsorption were pH, contact time, adsorbent and As(V) concentration. For leaching study four different leaching reagents (10mg C/L dissolved organic matter, 0.1M phosphate, 0.1M citrate and 0.1M oxalate) were used. The kinetics of arsenic adsorption on both type of ferrihydrites were similar with an equilibrium time of 1h; whereas, in case of aluminic ferrihydrite the equilibrium time was 3h. For aluminic ferrihydrite, maximum adsorption was found at pH 6.0. Whereas, for ferrihydrites pH 7.0 was found to be the best for As(V) adsorption. The highest As(V) adsorption capacity was shown by aluminic ferrihydrite (21.8 mg/g), followed by ferrihydrite prepared by emulsion method and ferrihydrite prepared by ordinary method (14.9 and 9.8 mg/g, respectively). In case of As(V) extraction from the loaded materials, the pH had a significant effect. In all cases, except citrate for aluminic ferrihydrite, extraction decreased with increasing pH in the range 5.0-8.0. For oxalate the iron extraction and for citrate the aluminium extraction followed the same trend as that for arsenic as a function of pH, suggesting that dissolution of these metals and consequent release of the adsorbed arsenic is one of the main mechanisms for arsenic extraction. However, for phosphate and DOM, the As(V) extraction mechanism was competition between arsenic and those anions for adsorption sites.
미생물처리를 이용한 산업폐기물로부터 금속의 제거 및 회수
안종관,김동진,Debaraj Mishra 한국자원공학회 2005 한국자원공학회지 Vol.42 No.5
Biometallurgical processes have been employed globally in the removal and recovery of valuable metals from industrial wastes. The toxicity of the mine waste contaminants can be abated by biosorption, bioremediation and biotransformation. In these conventional processes microorganisms play a potential role to mobilize the heavy metals and thus help in reducing toxicity. Metals like Hg, Cr, As, Se and Te can be transformed or volatilized by methanogenic bacteria. Bioleaching also has an attractive alternative in recovering metals from different industrial wastes. In these processes, metals like Zn, Cu, Al, Ni, Pb, Mn and Fe can be recovered from mine drainage, waste sludge, river sediments and electronic scrap. The present review describes different biological processes which are applied to treat industrial wastes. 산업폐기물로부터 유가금속의 제거와 회수시 최근에는 생물학적 제련법이 널리 주목받고 있다. 중금속을 용해시키거나 독성을 감소시키는 미생물을 이용하여, 흡착, 복원, 전환 등의 방법으로 광산 폐기물의 유독성을 감소시킬 수 있다. 수은, 크롬, 비소, 세륨 그리고 텔륨과 같은 금속은 메탄산화 박테리아에 의하여 변환되거나 용이하게 휘발된다. 또한 미생물 침출법을 활용할 경우, 광산폐수, 폐기물 슬러지, 하천 침전물, 전자 스크랩 등으로부터 아연, 구리, 알루미늄, 납, 망간 그리고 철과 같은 금속성분을 회수할 수 있다. 본 해설에서는 산업폐기물을 처리하는데 적용할 수 있는 여러 가지 생물학적인 처리방법에 대하여 기술하였다.
Removal of Arsenic(V) from Aqueous Solutions by Using Natural Minerals
Mohapatra Debasish,Mishra Debaraj,Chaudhury G. Roy,Das R.P.,Park, Kyung-Ho The Korean Institute of Resources Recycling 2006 資源 리싸이클링 Vol.15 No.5
The removal of arsenic(V) using four different natural minerals were evaluated. Parameters like contact time, pH, adsorbent dosages, and As(V) concentration were optimized. The kinetics of adsorption was observed to be fast and reached equilibrium within 2h. As(V) adsorption on studied minerals was dependent on pH and followed a pseudo-second-order reaction model. For kaolin, maximum adsorption was found at pH 5.0. Whereas, in case of other three minerals, a pH range of 6.0-7.0 was found to be the best for As(V) adsorption. The maximum adsorption capacity (Q) was calculated by fitting Langmuir equation to the adsorption isotherms obtained under a specified condition. From the slope of best fit, the Q values were calculated to be 2.07, 2.15, 1.95 and 0.86 mg As(V)/g of bauxite, wad, iron ore and kaolin, respectively. Desorption of As(V) from loaded materials was dependent on the type of leaching reagents used. Based on the results, it was found that among the studied natural minerals, wad was the best As(V) adsorbent.