Iodine recovery

The first iodine recovery from caUche occurred in 1852 the first iodine was exported to Europe in 1868, becoming the most important by-product of the nitrate production in terms of value. There are two ways for producing iodine from caUche iodates first, from solutions containing more equivalent iodine than its solubiUty as elemental iodine in the same solution of about 0.4 g/L at 25°C and second, from more diluted equivalent iodine solutions. 

Fig. 2. SQM s heap leaching of caUche tailings for iodine recovery from diluted iodate solutions.

Empty containers may be destroyed in an incinerator or decontaminated by washing with a dilute thiosulfate or sulfite solution. Bulk wastes should be treated by controlled iodine recovery processes. 

Iodine Recovery from sour brines Coils... 

Iodine, recovery of, from silver iodide residues, 2 6, 8 Iodine-131, purification of activity of carrier-free solutions of, 6 166... 

It appears that further research on HI chemistry could lead to processes for direct conversion of biomass to hydrocarbons without the economic penalty associated with operation at high pressure and temperature. The key to the value of such developments resides in the ability to recycle HI. Note that loss of only a small amount of the HI reacted can make the process quite uneconomical, so if it is developed to the point of commercial use, iodine recoveries would have to be substantially improved. 

Organic iodine recovery is less of a problem in a propylene process than in a butadiene process. Diiodobutene polymerizes in the quenching section, and methyl iodide-butadiene separation is difficult. 

The contents of the fla.sk are removed by means of a bent glass rod and filtered through a sintered-glass crucible under reduced pressure. The reddish-orange product is tamped to remove the remaining acid as completely as possible. Very little germanium(IV) iodide remains in solution, and the filtrate may be discarded or saved for iodine recovery. The crystalline mass is air-dried at room temperature or on a steam bath. A vacuum desiccator is not advised because of the volatility of the product. 

Gruverman, I. J. A Simple Carrier-Free Iodine Recovery Method. Trans. Am. Nucl. Soc. 7, 345 (1964). 19 2427... 

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