Results 131 to 140 of about 2,038 (178)

Sequential leaching of metals from spent refinery catalyst in bioleaching–bioleaching and bioleaching–chemical leaching reactor: Comparative study

Hydrometallurgy, 2014
The effect of sequential leaching such as bioleaching followed by bioleaching and bioleaching followed by chemical leaching is aimed at enhancing metal (Mo, Ni, V and Al) dissolution from a differently pretreated (acetone washed/decoked) spent catalyst.
Haragobinda Srichandan, Ashish Pathak
exaly   +2 more sources

Bioleaching of molybdenite

Hydrometallurgy, 2008
Abstract Molybdenum was bioleached from molybdenite-containing mine waste samples and from high purity molybdenite in solutions amended with ferrous sulfate. Bioleaching of Mo occurred when solution Eh exceeded 750 mV to 800 mV (s.h.e.). The rate of bioleaching of high purity molybdenite increased with decreasing particle size, averaging 3.22 mg Mo/m
Gregory J. Olson, Thomas R. Clark
openaire   +1 more source

Bioleaching of nepheline

Hydrometallurgy, 1987
Abstract Organic acid leaching of nepheline has been studied under batch and semi-continuous laboratory conditions. Rates of leaching by citric and oxalic acids (as purified compounds and as the mixed product of Aspergillus niger fermentation) have been compared with those of hydrochloric acid for batches of mineral (−37 +53 μm) and acid stirred at ...
Andrew B. King, A.William L. Dudeney
openaire   +1 more source

Bioleaching and Biomining

2016
Universal reserves of high-grade ores are diminishing at an alarming rate due to the rapid increase in the demand for metals. Biomining is the extraction of specific metals from their ores through biological means, usually microorganism. Biomining is done in two steps often called bioleaching and biooxidation.
Surabhi Mahajan, Ankur Gupta, Rajendra Sharma   +2 more
openaire   +1 more source

Modeling continuous bioleach reactors

Biotechnology and Bioengineering, 1999
The results of recent research have shown that the bioleaching of sulfide minerals occurs via a two-step mechanism. In this mechanism, the sulfide mineral is chemically oxidized by the ferric-iron in the bioleaching liquor. The ferrous-iron produced is subsequently oxidized to ferric-iron by the microorganism.
, Breed, , Hansford
openaire   +2 more sources

Competitive bioleaching of pyrite and chalcopyrite

Hydrometallurgy, 2006
Abstract An experimental study was conducted to investigate the heap bioleaching of a copper-gold concentrate using the Geocoat™ technique. Small-scale columns were operated at selected temperatures using bacterial consortia suited to these temperatures. In all experiments secondary copper sulfides would leach more rapidly than pyrite.
Petersen, Jochen, Dixon, David G
openaire   +2 more sources

Fluoride Toxicity in Bioleaching of Fluorapatite

Advanced Materials Research, 2015
The use of biohydrometallurgical processes may be restricted by microbial inhibition due to inhibiting fluoride originating from the feed material. In this work, phosphorus bioleaching experiments on fluorapatite ore were conducted in a reactor using Fe-and S-oxidizing bacteria, resulting in 56 % leaching yield for P, despite abundant (800 mg l-1) F in
Kinnunen, Päivi, Arnold, Mona, Priha, Outi, Sarlin, Tuija, Mäkinen, Jarno   +5 more
openaire   +2 more sources

Copper Recovery by Bioleaching of Chalcopyrite: A Microcalorimetric Approach for the Fast Determination of Bioleaching Activity

Advanced Materials Research, 2013
Low grade copper ores containing chalcopyrite are increasingly used for copper recovery via biomining. Since metal sulfide oxidation is an exothememic process, bioleaching activity can be measured due to the heat output by microcalorimetry, which is a non-destructive and non-invasive method.
Krok, Beate, Schippers, Axel, Sand, Wolfgang   +2 more
openaire   +1 more source

Investigating heap bioleaching: Effect of feed iron concentration on bioleaching performance

Minerals Engineering, 2010
This paper describes an investigation into the effect of iron concentration in the leach solution on the bioleaching of a low grade copper ore, where chalcopyrite was the dominant copper sulphide. The concentration of dissolved iron is primarily controlled by pH and the relative proportion of ferric to ferrous iron, with significant jarosite ...
van Hille, Robert P., van Zyl, Andries W., Spurr, Nicholas R.L., Harrison, Susan T.L.   +3 more
openaire   +3 more sources

Electrochemical Applications in Metal Bioleaching

2017
Biohydrometallurgy comprises the recovery of metals by biologically catalyzed metal dissolution from solids in an aqueous solution. The application of this kind of bioprocessing is described as "biomining," referring to either bioleaching or biooxidation of sulfide metal ores.
Christoph Kurt, Tanne, Axel, Schippers
openaire   +2 more sources