Fig. 4

Possible degradation pathways of SMX in Mn(II)/PAA/NTA process: (1) hydroxylation; (2) nitration; (3) bond cleavage; (4) coupling reaction. The product in “[ ]” was not detected in this study.

Possible degradation pathways of SMX in Mn(II)/PAA/NTA process: (1) hydroxylation; (2) nitration; (3) bond cleavage; (4) coupling reaction. The product in “[ ]” was not detected in this study.