An examination of the products formed on reaction of hydrogen cyanide and cyanogen with copper, chromium (6+) and copper-chromium (6+) impregnated activated carbons
✍ Scribed by B.R. Alves; A.J. Clark
- Publisher
- Elsevier Science
- Year
- 1986
- Tongue
- English
- Weight
- 915 KB
- Volume
- 24
- Category
- Article
- ISSN
- 0008-6223
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✦ Synopsis
The adsorption of HCN and (CN), by activated carbon impregnated with copper and chromium, both separately and in combination, was studied under dynamic conditions and compared with the corresponding performance of ASC whetlerite, a commercial HCN filtration medium. Gas penetration time as a function of carbon weight was used to calculate dynamic equilibrium uptake and adsorption rate constants whilst the products formed on the carbon supports were identified by mass spectrometry and quantitatively measured by a specially developed gaseous evolution method. Comparison was made with the infra-red analysis of products from reactions of (CN), and potassium cyanide with aqueous dichromate. From these studies, evidence is provided to support (CN), as an intermediate formed during HCN uptake in the presence of combined impregnants, and for its subsequent hydration in the presence of chromium (6 + ) to yield oxamide as the major product. A reaction scheme is proposed, consistent with these findings, which accounts for HCN chemisorption on copper-chromium impregnated carbon. Key WordsActivated carbon, hydrogen cyanide, cyanogen.