Effect of pyrrhotite reactivity on cyanidation of pyrrhotite 819 Figure 5 shows the reactivity of pyrrhotite, measured by cyanide consumption, as a function of formation temperature of the pyrrhotite.
Cyanide Gold Extraction Process Influencing Factors Slurry pretreatment The gold ore cyanide leaching pulp contains a certain amount of Fe2+, Cu2+, Zn2+, S2-, Fe3+ plasma, in addition to the metal sulfide mineral pyrite, pyrrhotite, chalcopyrite and sphalerite.
between gold and silver extractions and cyanide consumption. Ninity five Au % and 88.0% Ag extractions were obtained under the determined conditions of 24 h leaching duration, -74 µm particle size, ... minerals like pyrrhotite. In another study, Jeffrey and Breuer (2000) investigated the
COMPARISON OF DIFFERENT PYRRHOTITE DEPRESSANTS IN PENTLANDITE FLOTATION 3.1 INTRODUCTION Due to the similarities in mineralogy and chemical composition, and as well as the pyrrhotite collectorless flotation, it is difficult to achieve a clean separation between pentlandite and pyrrhotite. Pyrrhotite rejections has been a long-standing problem ...
The corrosion of black rolled mild steel in sodium cyanide solution is negligible. A piece of steel suspended in a sodium cyanide solution maintained at 0.05% NaCN and 0.001% CaO, in the presence of air, lost 0.002% of its weight in two weeks, this was equivalent to a penetration of 0.76 micron per year.Oxidized iron minerals such as hematite, magnetite, goethite, siderite and the silicate ...
This document is a general summary of cyanide's effects on human health and the environment, and is not intended to be a complete reference on all the environmental and health effects of cyanide. Human Health Effects Cyanide is produced in the human body and exhaled in extremely low concentrations with each breath. It is also produced by over 1,000 plant species including sorghum, bamboo and ...
Dec 26, 2019· One of the prevailing challenges in cyanidation is related to impurities such as copper and reactive sulfides such as pyrrhotite. Copper forms stable cyanocomplexes, which increase the consumption of sodium cyanide in the process (Marsden and House 2006).Pyrrhotite and other sulfides can lead to high oxygen requirements due to the oxidation reactions of Fe 2+ to Fe 3+ and …
The reason for the lower cyanide consumption obtained with intense aeration is probably connected with the reactions which take place when alkaline sulphide decomposes in cyanide solution. Alkaline sulphide is one of the initial products of the reaction between pyrrhotite and alkaline cyanide solution.
The effect of the metal to sulphur ratio in the nonstoichiometic compound, pyrrhotite, is related to the consumption of cyanide in gold leaching. Reactive pyrrhotite (Fe (I-X) S) is produced during the pyrolysis of refractory pyrite (FeS 2). Iron vacancies give pyrrhotite its non stoichiometric nature and determine its fugacity and hence ...
improved cyanide consumption, leaching kinetics as well as overall gold extraction. Pretreatment with lead nitrate and low DO produced fast leaching kinetics, low cyanide consumption and high extraction of gold for the Eleonore pyrrhotite concentrate. Aurostibite, …
Samples that were partially converted to pyrrhotite, and hence remained in equilibrium with the unconverted pyrite, showed an increase in cyanide consumption with increasing metal to sulphur ratio.
The effects of dissolved oxygen and cyanide dosage on gold extraction from a pyrrhotite-rich ore Article in Hydrometallurgy 72(1-2):39-50 · February 2004 with 1,534 Reads How we measure 'reads'
It was reported that pre-leaching successfully overcame the effect of pyrite and pyrrhotite on cyanide consumption and the gold leaching kinetics, but it had no beneficial effect when chalcopyrite was present. It was suggested that lead nitrate prevented copper and iron dissolution by forming a passive layer at the surface of sulfide minerals.
Using cyanide to recover gold from sulfide ores generally results in 30 to 35% recovery, and the best I have heard of is around 50% recovery. The fine coating of a iron compound definitely appears to be a key component of the inability of cyanide to efficiently leach low grade pyritic ores.
If this is not done, it is very difficult to maintain a pH of >10, which is needed to maintain cyanide in the free cyanide form rather than the toxic, gaseous HCN form. The pH constantly drifts downwards due to the slow consumption of lime by basic iron sulphate, which leads to the formation of HCN gas, and creates an unsafe working environment ...
increase in cyanide consumption. The introduction of lead nitrate resulted in a 34 g/t decrease in cyanide consumption. According to La Brooy, Linge, and Walker (1994), reactions involving sulphides may consume cyanide and oxygen and produce various solution species that can decrease the efficiency of gold leaching. Pyrrhotite is the most ...
Nov 28, 2016· The reasons of gold refractory, Gold ore classification, and preprocessing methods. Published on November 28, 2016 November 28, 2016 • 60 Likes • 9 Comments
1995). The transformation of pyrite to pyrrhotite, using pyrolysis, indicated that the cyanide consumption gradually decreases with an increase in the pyrrhotite content of the sample (Browner and Lee, 1998). This finding means that pyrrhotite is less reactive than pyrite in a cyanide solution. The reactivity of pyrrhotite * Corresponding author.
Reactions of gold and sulfide minerals in cyanide media ... while reducing the cyanide consumption from 5.8 to 1.2 kg/t NaCN. ... it was found that pyrrhotite did not generate a high cyanide ...
Pre-aeration increases the Eh and oxidises the active pyrite and pyrrhotite to reduce cyanide consumption in the leach process. This is different from the patented Albion Process, where significant portions of sulphides (over 10%) are oxidised by atmospheric leaching to increase metal recovery.
cyanide consumption; and (iv) stage dissolution or residue values achieved. Lime and cyanide consump- ... the ore body with a predominantly pyrrhotite min-eralisation. Cyanide and lime consumption are reported in kg/t of concentrate with typicalﬂotation mass pulls of between 10 and 11%. Under these
the dissolution of metallic sulfides, thus reduces cyanide consumption (Deschenes et al., 2003). Metallic sulfides such as pyrite, chalcopyrite and pyrrhotite show different reaction mechanisms with lead nitrate. Lead nitrate passivizes the pyrite by forming a hydroxide (Pb(OH) 2
Cyanide Leaching Chemistry & Gold Cyanidation. Previous Next ... Not only do copper minerals dissolve in cyanide and cause excessive consumption of this chemical, but also, the copper cyanogen complexes thus formed indirectly affect the dissolution of the gold. ... whereas a difference in the pyrrhotite content of the ore might affect seriously ...
Apr 17, 2016· Pyrite is the most stable but when pyrrhotite is present trouble is usually experienced both in regard to cyanide consumption and gold extraction. Pyritic flotation concentrates are often reground for gold liberation before cyanidation as at Itogon-Suyoc Itogon, and Pamour.
Gold was present as native gold and electrum. A test conducted at 2000 ppm NaCN and pH 11.0 produced 97.0% extraction of gold in 72 h. It was found that an efficient leaching required only 3–5 ppm DO. However, the presence of reactive pyrrhotite resulted in a cyanide consumption …
pyrrhotite are some of the most common. The first cyanidation plant in the world was ... cyanide species, arsenic, certain metals and sulphur species) ... reagent consumption, discharge control and amelioration-specific measures. Practically, it would be unrealistic to affect ...
Optimum results as regards gold extraction and cyanide consumption are obtained when using well aerated cyanide solutions containing at least 0.05% CaO and saturated with calcium sulphate. Laboratory results showing the cyanicidal effects of pyrrhotite under various conditions were given.
The new leaching conditions also reduced significantly cyanide consumption from 12–15 kg/t to 3.5–4.0 kg/t. At a P80 of 21 μm, the cyanidation with 4.5 g/L NaCN, 25 ppm DO, 1 g/L lime yielded ...
- rock crusher power consumption
- raw crusher power consumption calculations
- rock phosphate crushing plant power consumption
- sand and aggregate consumption in civil
- rcc material consumption calculator
- sag mill ball consumption rate
- production and consumption in ethiopia
- sand consumption m10 grade concrete
- reason of high power consumption in coal crushers
- sand washing water consumption
- sand consumption in m20 grade concrete
- rolls press cement mills power consumption
- ready mix concrete m25 ratio cement consumption
- rolling mill consumption of coal in nepal
- reducing power consumption in ball mill
- reduce consumption of cement
- pulverizer electicity consumption
- raymond mills specific power consumption
- pulveriser for roto molding power consumption
- rotary dryer power consumption
- ready mix concrete cement consumption in m25m3035
- producers of sodium cyanide australia
- recovery of gold from cyanide solution
- reaction between silver nitrate and sodium cyanide
- refining gold from ore without cyanide
- reaction of cyanide silver ore mining
- pyrrhotite for sale
- pyrrhotite processing
- pyrrhotite pyrite malawi
- proper concentration of cyanide in gold extractio
- purchasing 98 sodium cyanide for pro tonne sale in the usa
- refine gold cyanide
- recovery silver from silver cyanide mud
- redesign of hammer mill to reduce power consumption
- sanjay gupta cyanide