Adsorption of Silver Cyanide on Activated Carbon
The Nature of Activated Carbon “Activated carbon” or “activated charcoal” is a generic term applied to amorphous carbon materials that have adsorptive capability. These materials are made from different sources and are available as powder, pellets, or grains. Their common characteristic is a very large surface area in the range of 600 to 1200 m²/g […]
Laboratory Testing in a Tri-Flo Heavy Media Separator
Heavy media separation is one of a number of pre-concentration techniques for coarse feed which, when the ore is amenable, offers economic advantages in the mining stage and/or the processing stage. In mining, simpler and cheaper methods may be used if a greater proportion of waste material can be included in the mining blocks that […]
Thiourea for Extraction of Gold & Silver from Silver Ores
Leaching Chemistry of Gold Silver and Manganese Thiourea is a reducing and complexing agent and can be used for the processing of gold and silver. The redox potential of gold(I) and silver(I) thiourea complexes in acidic thiourea solutions are 0.380 and 0.023 V (vs SHE), respectively (Kazakov et al., 1983; Lodeishchikov et al., 1975). Thiourea, […]
Using Wetlands for the Control of Acid Mine Drainage
Metal Removal Processes of Wetlands A wetland environment can remove metals from influent waters in a variety of ways. As chemical oxidation takes place, oxides and hydroxides of iron can be expected to precipitate from surface flow, resulting in the characteristic yellow sediment in mine drainage known as “yellow boy”. These precipitates coat the surfaces […]
How to Improved Fine Particle & Bubble Flotation
Selective beneficiation of fine particles depends heavily upon the flotation separation process. Conventional froth flotation for many ore systems is very effective for particles between 300 and 20 µm in size, but the flotation efficiency commonly drops off as the particle size decreases below 20 µm. Flotation kinetics has been used by Sutherland (1955) and […]
Methods of Improving Mineral Flotation Circuit
The process of froth flotation as a means of upgrading the quality of coal by removing ash/pyrite and of separating selected mineral(s) from undesired gangue materials is certainly one of the most common unit engineering operations in use today. Flotation has been successfully practiced at the industrial scale for well over 50 years, and if […]
Chemistry of Slurry Rheology Control by Grinding Aids
Tests run on using organics to influence the fracture strength of solids gave an almost bewildering array of results on the four substrates. Two general classes of tests were carried out: 1) a procedure consisting of introducing a notch in a small rectangular sample, placing this sample in an environmentally controlled chamber for humidity, chemical […]
Flocculation & Lewis Acid-Base Theory
The use of synthetic polymers such as polyacrylamide and its derivatives to dewater mineral-processing waste streams has become commonplace. The use of polymers often solve many of the solid-liquid separation problems encountered by the industry. However, using polyacrylamides to dewater clay containing minerals such as montmorillonite and kaolin often produces a dewatered material containing a […]
Hydrocyclone Modelling Method
Mineral and chemical industries use the hydrocyclone for size classification as well as solid-liquid separation. The geometry of the device being very simple, a tangential involute section attached to a cylindrical section and a conical section attached to the other end of the cylinder, the device has found widespread use. Majority of the research papers […]
Agitative Agglomeration
Agitative agglomeration is the process of the consolidation of particles into larger shapes by means of agitation with a liquid. Most fine powders can readily be formed into granular masses by admixture with a liquid and by utilizing a suitable agitation method. Ideally, each particle should be coated with the liquid by stirring or moving […]