Abstract—Polychlorinated biphenyls (PCBs) are toxic
pollutants that need to be cleaned and removed from our
environment. In this work we have investigated the destruction
of PCBs using microwave heating, conventional heating PCBs
in water-hydrogen peroxide or water-sodium hydroxide
systems. After heating, liquid-liquid extraction of the reaction
mixtures was conducted prior to GC analysis. Our results
revealed that the degradation efficiency obtained by
microwave heating ranged from 18% to 53%. Fortunately,
PCB-118, PCB-156, and PCB-180 congeners were effectively
degraded in subcritical water with hydrogen peroxide or
sodium hydroxide. Higher concentration of hydrogen peroxide
and longer heating time increased PCB degradation. Over 91%
PCB degradation was achieved for all three PCB congeners
after 6 hours of heating at 350 °C with 30% hydrogen peroxide
in water. The concentration of sodium hydroxide in water had
only a mild influence on PCB degradation. However, high
temperature significantly enhanced the efficiency of PCB
degradation in water-sodium hydroxide system. All three PCB
congeners investigated were completely destroyed after
heating in 0.2% sodium hydroxide at 350 °C for an hour.
Index Terms—Polychlorinated biphenyls, PCBs, destruction,
subcritical water, hydrogen peroxide, sodium hydroxide.
The authors are with the Department of Chemistry, East Carolina
University, Greenville, North Carolina, USA (e-mail: YANGY@ecu.edu).
[PDF]
Cite: Ninad Doctor and Yu Yang, "Destruction of Polychlorinated Biphenyls under Subcritical Water Conditions in the Presence of Hydrogen Peroxide or Sodium Hydroxide," International Journal of Chemical Engineering
and Applications vol. 9, no. 4, pp. 119-122, 2018.
