Subcritical Water-Driven Complete Mineralization of Silane Coupling Agents with Short Perfluoroalkyl Chains.

The decomposition of CFCHCHSi-(OMe) and CFCHCHSi-(OMe)typical fluorinated silane coupling agents used for surface modificationwas investigated in subcritical water for potential waste treatment applications. When CFCHCHSi-(OMe) was heated in subcritical water with no additive at 350 °C, only a small amount of fluoride (F) was produced. In contrast, virtually complete mineralization of CFCHCHSi-(OMe) was achieved in the presence of KMnO. Specifically, after treatment with 0.50 mmol of KMnO for 6 h, the F yield reached 100%, and the residual total organic carbon in the reaction solution was reduced to 4% of the initial carbon content of CFCHCHSi-(OMe). Furthermore, under the same reaction conditions, quasi-complete mineralization of CFCHCHSi-(OMe) was also attained, with an F yield of 96% and a remaining TOC ratio of 2%.