Thiocyanuric acid is the organosulfur compound with the formula (HNC=S)3. It is analogous to cyanuric acid ((HNC=O)3). 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.[2]
The compound is mildly acidic, with pKa's of 5.7, 8.4, and 11.4.[3] Various salts of (HNC=S)−3 have been characterized.[4]
The compound has an affinity for heavy metals. This attribute has been exploited by applying thiocyanuric acid and derivatives to treatment of waste waters.[5]
^ abHenke, Kevin R.; Hutchison, Aaron R.; Krepps, Matthew K.; Parkin, Sean; Atwood, David A. (2001). "Chemistry of 2,4,6-Trimercapto-1,3,5-triazine (TMT): Acid Dissociation Constants and Group 2 Complexes". Inorganic Chemistry. 40 (17): 4443–4447. doi:10.1021/ic0103188. PMID11487353.
^Dean, Philip A. W.; Jennings, Michael; Houle, Teena M.; Craig, Donald C.; Dance, Ian G.; Hook, James M.; Scudder, Marcia L. (2004). "Crystal packing in tetraphenylphosphonium salts of trithiocyanuric acid and its methanol solvate". CrystEngComm. 6 (88): 543. doi:10.1039/b413145b.
