Polyacrylic acid-b-polyptyrene covered Ni/Fe nanoparticles to remove 1,1,1-trichloroethane in water

A new material, polyacrylic acid-b-polyptyrene (PAA-b-PS) covered Ni/Fe nanoparticles (PAA-b-PS-nZVI-Ni), was developed and evaluated for the selective dechlorination of 1,1,1-trichloroethane (1,1,1-TCA) in the presence of potential interferents. The average size of the PAA-b-PS coated Fe/Ni bimetallic nanoparticles was approximately 50 nm, which resulted from agglomeration prevention by PAA-b-PS. The removal efficiency of 1,1,1-TCA by an optimal dose with a 1.0 g/L Fe/Ni (Ni/Fe = 2 wt%) and 0.5 g/L PAA-b-PS-coated concentration was higher (87.5%) than that of bare Fe/Ni (60%). The pseudo-first-order rate constant (K_obs) of 1,1,1-TCA removal by PAA-b-PS-nZVI-Ni was 0.0142 min^-1 within 240 min. Comparatively, the K_obs values of 1,1,1-TCA removal by other materials (Fe, pure bimetallic Fe/Ni, PAA-b-PS-Fe) were only 0.003, 0.0052 and 0.0103 min^-1, respectively. The 1,1,1-TCA removal efficacy by PAA-b-PS-nZVI-Ni showed no obvious gap regardless of pH or various common inorganic anions (NO₃^-, HCO₃^- and SO₄^2-) at different concentrations. However, humic acid (HA) had great influence on the degradation of 1,1,1-TCA. In conclusion, PAA-b-PS-covered Ni/Fe nanoparticles with its selectivity high effectiveness could be used as one remedial agent for the degradation of 1,1,1-TCA in water.