PHOTOCHEMISTRY OF AQUEOUS-SOLUTIONS OF DICYANOMERCURY(II) AND POTASSIUM TETRACYANOMERCURATE(II)

Citation
Ws. Rader et al., PHOTOCHEMISTRY OF AQUEOUS-SOLUTIONS OF DICYANOMERCURY(II) AND POTASSIUM TETRACYANOMERCURATE(II), Journal of solar energy engineering, 116(3), 1994, pp. 125-129
Citations number
20
Categorie Soggetti
Engineering, Mechanical","Energy & Fuels
ISSN journal
01996231
Volume
116
Issue
3
Year of publication
1994
Pages
125 - 129
Database
ISI
SICI code
0199-6231(1994)116:3<125:POAODA>2.0.ZU;2-I
Abstract
Photochemically induced reactions of dicyanomercury(II) and potassium tetracyanomercurate(II) in alkaline aqueous solutions were investigate d in detail. The studies were conducted in the presence or absence of a titanium (IV) oxide semiconductor photocatalyst utilizing sunlight a s the irradiation source. It was established that the cyanide ion libe rated from the thermodynamically stable mercury-cyano species can be p hotocatalytically oxidized via cyanate and nitrite to nitrate. In addi tion, the process removes over 99 mol% of mercury from the solution. I n the absence of the photocatalyst, no photoproducts were detected and mercury remained in solution. The results obtained may have ramificat ions for the use of solar power for the efficient treatment of large q uantities of precious metals mill tailings wastes containing various c yanide species. In addition, in order to follow the fate of cyanide in these experiments, a novel gas-diffusion flow injection analysis syst em for the determination of cyanide from the thermodynamically stable mercury-cyano complexes was utilized.