Galena separation processes

The technique is known as the cupellation process. The galena ore was roasted, which converted it to lead oxide, litharge, which was easily reduced by charcoal. If silver was present in the galena it stayed in the lead metal The separation process worked in the following way ... 

Liu, Q., and Laskowski, J. S. 1989b. The role of metal hydroxides at mineral surfaces in dextrin adsorption, II. Chalcopyrite-galena separations in the presence of dextrin. Int. J. Miner. Process. 27 147. 

Preparation of the Media Various sohd materials have been used to prepare the media. In the initial development of the process, a suspension of sand and also mixtures of barite and clay were used for separating coal from slate. Galena (lead sulfide mineral) was also used... 

A simple two-mineral separation, say of galena (specific gravity 7.5) from a siliceous gangue (specific gravity 2.65) can be taken as a good example to illustrate the process. The flotation operation comprises the following successive steps. 

The attachment of minerals to the bubbles, which is the heart of the flotation process, occurs. Once this occurs, gravity completes the separation readily. In the present example, galena attaches itself to the bubbles and thereby its effective density is drastically reduced. This causes galena to buoy up in spite of the fact that it is, in reality, much heavier than the siliceous gangue. 

A mixture of quartz and galena of a size range from 0.015 mm to 0.065 mm is to be separated into two pure fractions using a hindered settling process. What is the minimum apparent density of the fluid that will give this separation How will the viscosity of the bed affect the minimum required density ... 

A mixture of quartz and galena of densities 3700 and 9800 kg/m3 respectively with a size range of 0.3 to 1 mm is to be separated by a sedimentation process. If Stokes Law is applicable, what is the minimum density required for the liquid if the particles all settle at their terminal velocities ... 

Lead is produced commercially from its principal ore, galena (PbS). The ore is associated with sulfides of several metals including iron, copper, zinc, silver, bismuth, arsenic, antimony and tin. The ore is crushed and ground. It then is selectively separated from gangue and other valuable minerals by one or more processes that include gravity separation and flotation. Selective... 

After the unsuccessful inspection of hundreds of samples with highly sensitive techniques attempts were made to improve the sensitivity of such searches by enrichment of superheavy elements from very large quantities. The extreme case [47] was a search for element 114 in flue dust collected during the industrial processing of 103 to 104 tons of galena. Eka-lead should be more volatile than lead and, hence, be enriched in flue dust. After further concentration by chemical and mass separations, the final samples were exposed to neutrons but no fission events were found with track detectors. The deduced concentration limit of 10-19 to 10 23 g/g is the lowest ever achieved in searches in Nature. 

A sedimentation process is to be used to separate pulverized coal from slate. A suspension of finely divided particles of galena (lead sulfide, SG - 7.44) in water is prepared. The overall specific gravity of the suspension is 1.48. 

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