Glutathione promoted Fenton degradation: a cocatalyst based on -HS/-S-S cycle with hydroxyl radicals
Glutathione, a kind of tripeptide with thiol, was introduced into traditional Fenton system. It is found that target pollutant degradation has been greatly improved when adding glutathione into Fenton system, due to accelerating the Fe(II)/Fe(III) cycle, thus generating more hydroxyl radicals. The variables of the concentration of Fe(II), H2O2 and the generation of HO• were monitored to verify the catalytic action of glutathione. And operating variables such as pH, molar ratios and different atmospheres were examined, and the cyclic degradation experiments were performed to explore the stability of catalysts. The electrospray ionization mass spectrometry (ESI-MS) was used to determine the transformation of different forms of glutathione to explore the catalytic mechanism. More importantly, it is found that other thiol compounds can also promote the Fenton degradation through the cycle of thiol compounds and theirs oxidized form. In conclusion, it is a cocatalyst based on -HS/-S-S cycle with hydroxyl radicals, which has not been reported previously.