Influence of initial pH on bioleaching of heavy metals from contaminated soil employing indigenous Acidithiobacillus thiooxidans

Kumar, R. Naresh; Nagendran, R.

doi:10.1016/j.chemosphere.2006.07.091

Cited by 67 publications

(33 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The procedure used for isolation of culture is detailed in Kumar and Nagendran (2007). The isolated culture was tested for its ability to utilize iron as energy source by growing it in 9K medium (Silverman and Lundgren 1959).…”

Section: Isolation and Identification Of Indigenous A Thiooxidansmentioning

confidence: 99%

Bioleaching of heavy metals from contaminated soil using Acidithiobacillus thiooxidans: effect of sulfur/soil ratio

Nareshkumar

Nagendran

Parvathi

2007

World J Microbiol Biotechnol

Self Cite

View full text Add to dashboard Cite

Bioleaching of heavy metals from contaminated soil was carried out using indigenous sulfur oxidizing bacterium Acidithiobacillus thiooxidans. Experiments were carried out by varying sulfur/soil ratio from 0.03 to 0.33 to evaluate the optimum ratio for efficient bioleaching of heavy metals from soil. The influence of sulfur/soil ratio on the bioleaching efficiency was assessed based on decrease in pH, increase in oxidation-reduction potential, sulfate production and solubilization of heavy metals from the soil. Decrease in pH, increase in oxidation-reduction potential and sulfate production was found to be better with the increase in sulfur/soil ratio. While the final pH of the system with different sulfur/soil ratio was in the range of 4.1-0.7, oxidation reduction potential varied from 230 to 629 mV; sulfate production was in the range of 2,786-8,872 mg/l. Solubilization of chromium, zinc, copper, lead and cadmium from the contaminated soil was in the range of 11-99%. Findings of the study will help to optimize the ratio of sulfur/soil to achieve effective bioleaching of heavy metals from contaminated soils.

show abstract

Section: Isolation and Identification Of Indigenous A Thiooxidansmentioning

confidence: 99%

Bioleaching of heavy metals from contaminated soil using Acidithiobacillus thiooxidans: effect of sulfur/soil ratio

Nareshkumar

Nagendran

Parvathi

2007

World J Microbiol Biotechnol

Self Cite

View full text Add to dashboard Cite

show abstract

“…The 9 K medium contains (per liter) 3.0 g of (NH 4 ) 2 SO 4 , 0.5 g of K 2 HPO 4 , 0.5 g of MgSO 4 Á7H 2 O, 0.1 g of KCl, 0.01 g of Ca(NO 3 ) 2 and 44.3 g of FeSO 4 Á7H 2 O (Wang et al 2009). The modified Starkey medium contains (per liter) 0.3 g of (NH 4 ) 2 SO 4 , 3.5 g of KH 2 PO 4 , 0.5 g of MgSO 4 Á7H 2 O, 0.25 g of CaCl 2 , 14.905 g of FeSO 4 Á7H 2 O and 5 g of elemental sulfur (Kumar and Nagendran 2007). The initial pH values of 9 K medium and modified Starkey medium were adjusted to 2.0 and 3.0, respectively.…”

Section: Preparation Of Inoculumsmentioning

confidence: 99%

“…Fortunately, bioleaching can mobilize metals from ores or tailings (Liu et al 2007;Baba et al 2011). It was also applied to leach metals from waste electronic products (Xiang et al 2010), fly ashes (Carranza et al 2009), and even from soils, sediments and sludge (Xiang et al 2000;Chen and Lin 2001;Kumar and Nagendran 2007). The process enables heavy metals to be leached out from solid to liquid either directly by acidophilic bacteria or indirectly by the products of metabolism (Chen and Lin 2004).…”

Section: Introductionmentioning

confidence: 98%

Simultaneous heavy metals removal and municipal sewage sludge dewaterability improvement in bioleaching processes by various inoculums

Shi

Zhu

Shang

et al. 2015

World J Microbiol Biotechnol

View full text Add to dashboard Cite

The heavy metals content and dewaterability of municipal sewage sludge (MSS) are important parameters affecting its subsequent disposal and land application. Six kinds of inoculums were prepared to examine the characteristics of heavy metals removal and MSS dewaterability improvement in bioleaching processes. The results showed that Cu, Zn and Cd bioleaching efficiencies (12 days) were 81-91, 87-93 and 81-89%, respectively, which were significantly higher than those of Fe-S control (P < 0.05) and blank control (P < 0.01). The bioleaching boosted by the prepared inoculums could also significantly enhance MSS dewaterability (P < 0.01). The centrifugal dehydration efficiency of MSS rose from 73.00 to 90.00% at day 12. Microscopic observations and energy dispersive spectrum analysis demonstrated that the dewaterability improvement might be attributed to the changes of sludge structure from flocculent to obvious granular and the formation of secondary minerals mainly consisting of iron, oxygen and sulfur elements. The results above demonstrated that bacterial consortium enriched from acid mine drainage (AMD) was suitable to boost sludge bioleaching for heavy metals removal and dewaterability improvement. It also suggested that the synergy of sulfur/ferrous-oxidizing bacteria (SFOB) enriched from AMD and the cooperation of exogenous and indigenous SFOB significantly promoted bioleaching efficiencies.

show abstract

“…After 9 days of bioleaching, ORP of mixed liquor increase from the initial value 113,101, 95 and 128 mV to 552, 522, 517 and 608 mV for PS, OS, AS and SS, respectively, which is attributed to oxidation of ferrous sulfate. The ORP shows a rapid increase in the first three days and a flat growth follows in the end [17]. Fig.…”

Section: Ph and Orpmentioning

confidence: 99%

Transformation of heavy metals from sewage sludge during bioleaching

Zheng¹,

Wu²,

Zhang³

2016

Proceedings of the 2015 2nd International Conference on Machinery, Materials Engineering, Chemical Engineering and Biotechnolog

View full text Add to dashboard Cite

Bioleaching experiment was carried out in 80L SBR reactor with sewage sludge collected from each treatment step of the wastewater treatment plant (WWTP) system, to investigate the transformation of heavy metals during bioleaching. The corresponding changes in pH, oxidation-reduction potential (ORP) and the concentration of Zn, Cu and Pb in extracellular polymeric substances (EPS) were also studied. The results showed that the physical and chemical properties of sewage sludge could affect the sludge acidification and raise the ORP by oxidizing ferrous sulfate. The highest total concentration of Zn-EPS, Cu-EPS, and Pb-EPS was found in secondary sludge (SS), primary sludge (PS) and aerobic sludge (OS), respectively. Content of Pb in LB-EPS was more than in TB-EPS during 9 days bioleaching. Concentration of Cu and Zn in LB-EPS was better in the early leaching period while that in TB-EPS was at the end. Most of Zn existed in their forms of Fe-Mn oxides-bound in raw sludge (50.87%-61.79% of the total), followed by the organic oxide bound. The organic oxide bound was the predominant fraction of Cu (50.14-70.15% of the total) and Pb (41.28-61.94% of the total) in all original sludge samples. After bioleaching, Pb in primary sludge (PS) remained as the residual fraction, while the Fe-Mn oxides bound fraction in aerobic sludge (OS), anaerobic sludge (AS) and secondary sludge (SS). Zn existed as a high available fraction (F 1+2 ) in primary sludge (PS), aerobic sludge (OS) and anaerobic sludge (AS) but the residual fraction in secondary sludge (SS) after bioleaching. For Cu in all bioleached sludge, the predominant fraction was the residual fraction (average 32.71% of the total).Significant differences of the formation of heavy metals were observed in different sludge system during bioleaching, suggesting that the species of sludge significantly affected the distribution of various fractions of the metals in bioleaching.

show abstract

Influence of initial pH on bioleaching of heavy metals from contaminated soil employing indigenous Acidithiobacillus thiooxidans

Cited by 67 publications

References 23 publications

Bioleaching of heavy metals from contaminated soil using Acidithiobacillus thiooxidans: effect of sulfur/soil ratio

Bioleaching of heavy metals from contaminated soil using Acidithiobacillus thiooxidans: effect of sulfur/soil ratio

Simultaneous heavy metals removal and municipal sewage sludge dewaterability improvement in bioleaching processes by various inoculums

Transformation of heavy metals from sewage sludge during bioleaching

Contact Info

Product

Resources

About