Synthesis of monodispersed CMC-stabilized Fe-Cu bimetal nanoparticles for in situ reductive dechlorination of 1, 2, 4-trichlorobenzene

Monodispersed carboxymethyl cellulose (CMC)-stabilized Fe-Cu bimetal nanoparticles with an average diameter of less than 20nm were successfully synthesized by a modified water-based approach. The as-resulting particles exhibit a core-shell structure and are quite uniform in size and shape. Batch experiments demonstrated that these nanoparticles could effectively dechlorinate 1,2,4-trichlorobenzene (1,2,4-TCB). Near 90% of reduction efficiency was achieved by CMC-stabilized Fe-Cu for 24h treatment. By monitoring the reaction products with time by GC-MS, it was found that 1,2,4-TCB transformation mainly followed the sequential hydrogenolysis to 1,2-dichlorobenzene (12DCB), then chlorobenzene (CB) and eventually benzene. The pseudo first order 1,2,4-TCB degradation rate were 0.09h^-1 and 0.06h^-1 as CMC-to-Fe molar ratios were 0.00248 and 0.00124, respectively. Dechlorination mechanism was also proposed in this study.