Thiocyanuric acid
Thiocyanuric acid is the organosulfur compound with the formula. It is analogous to cyanuric acid. Cyanuric acid is white whereas thiocyanuric acid is yellow. It can also be viewed as a trimeric thioamide.
Structure
It is a planar molecular as determined by X-ray crystallography. Like cyanuric acid, thiocyanuric acid forms extended hydrogen-bonded network resulting in a sheet-like structure. This arrangement is relevant to the high melting point of the compound.Synthesis, reactions, applications
Thiocyanuric acid precipitates from warm, acidic solutions of thiocyanic acid. A modern synthesis begins instead with a preformed ring: cyanuric chloride reacts with sodium hydrosulfide to give table salt and thiocyanuric acid.The compound is mildly acidic, with pKa's of 5.7, 8.4, and 11.4. Various salts of have been characterized.
The compound has an affinity for heavy metals. This attribute has been exploited by applying thiocyanuric acid and derivatives to treatment of waste waters.