Other Collectors

Xanthates and dithiophosphates dominate sulfide flotation usage, though several other collectors including more recently developed ones are gaining acceptance rapidly (43). As of this writing, this is an active area of research. Many of the sulfide collectors were first used ia the mbber iadustry as vulcanizers (16). Fatty acids, amines, and sulfonates dominate the nonsulfide flotation usage. The fatty acids are by-products from natural plant or animal fat sources (see Fats and fatty oils). Similarly petroleum sulfonates are by-products of the wood (qv) pulp (qv) iadustry, and amines are generally fatty amines derived from fatty acids. 

AEROPHINE 3418A promoter is widely used ia North and South America, AustraHa, Europe, and Asia for the recovery of copper, lead, and ziac sulfide minerals (see Elotatton). Advantages ia comparison to other collectors (15) are said to be improved selectivity and recoveries ia the treatment of complex ores, higher recoveries of associated precious metals, and a stable grade—recovery relationship which is particularly important to the efficient operation of automated circuits. Additionally, AEROPHINE 3418A is stable and, unlike xanthates (qv), does not form hazardous decomposition products such as carbon disulfide. It is also available blended with other collectors to enhance performance characteristics. 

In the general case, when arbitrary interaction profiles prevail, the particle deposition rate must be obtained by solving the complete transport equations. The first numerical solution of the complete convective diffusional transport equations, including London-van der Waals attraction, gravity, Brownian diffusion and the complete hydrodynamical interactions, was obtained for a spherical collector [89]. Soon after, numerical solutions were obtained for a panoplea of other collector geometries... 

There are only a few collectors suitable for tin flotation that have been introduced into operating plants in the 1970s, but today they have been replaced (i.e. arsonic acid, phospho-nic acid) due to toxicity and high prices. Other collectors that have been extensively studied include oleic acid, sodium oleate, alkyl phosphoric acid and hydroxamates [2—4],... 

Other Collectors Tarry particulates and other difficult-to-handle liquids have been collected on a dry, expendable phenol formaldehyde-bonded glass-fiber mat (Goldfield, J. Air Pollut. Control Assoc., 20, 466 (1970)] in roll form which is advanced intermittently into a filter frame. Superficial gas velocities are 2.5 to 3.5 m/s (8.2 to 11.5 ft/s), and pressure drop is typically 41 to 46 cm (16 to 18 in) of water. Collection efficiencies of 99 percent have been obtained on submicrometer particles. Brady [Chem. Eng. Prog., 73(8), 45 (1977)] has discussed a clean-able modification of this approach in which the gas is passed through a reticulated foam filter that is slowly rotated and solvent-cleaned. 

Then I suggest we make sure some better agents take a closer look. If we can t immediately collect the items we want, then we can at least pick up some other collectors. ... 

Pipes, valves, fittings, heat exchangers, or magnetic, electrostatic, or other collectors made of graphite or coated in graphite, yttrium, or yttrium compounds resistant to the heat and corrosion of uranium vapour. 

A collector may entrain a trace constituent as a result of similarities in their solubilities. Other collectors function by coprecipitation, in which the minor component is adsorbed on or incorporated into the collector precipitate as the result of mixed-crystal formation. Clearly, the collector must not interfere with the method selected to determine the trace component. 

In other words, these results show calcite and apatite to interchange approximately their isoelectric points in the supernatants of each other. This suggests surface conversion of apatite to calcite and calcite to apatite respectively. Implications of such conversion on selective flotation is to be noted. In flotation, the presence of flotation reagents such as oleate or other collectors actually complicates the system behavior even further and this aspect is discussed in a subsequent section. 

Infrastructure (terminals, train stations) ]2% Petrol stations ]2% Sport facilities ]4% Others (collectors, sculptures, etc.) ]5% Schools, universities 8% Laboratories storage, greenhouses 19% Zoological gardens Museums, pavilions Swimming pools Offices, residential accommodation... 

If too large an excess of borax is added to the charge then the fluidity of the melt is diminished with subsequent retention of lead or other collector, and thus PMs, in the slag. 

In the washing zone the cake is washed by the nozzles (or wash headers)-8. The campartmeot is connected through the port-6, which is also tied into a vacuum source. The wash liquor is removed in the other collector. 

Other Collectors for Sulfide Minerals 1.9.1 Disulfides and Esters of Dithiophosphates (1) Disulfides of dithiophosphates... 

Other Collectors for Sulfide Minerals The reaction can be given by the following ... 

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