Hydrodechlorination of p-Chlorophenol on Pd-Coated Fe.sub.3O.sub.4@polypyrrole Catalyst with Ammonia Borane as Hydrogen Donor

Ammonia borane (AB) (hydrogen donor), was used for the hydrodechlorination of p-chlorophenol on Fe.sub.3O.sub.4@PPY@Pd at room temperature and pressure. Fe.sub.3O.sub.4@PPY@Pd was characterized by scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The high-performance liquid chromatography and carbon balance results showed that p-chlorophenol was efficiently and quantitatively transformed into phenol. At the AB and catalyst contents of 2.5 mmol and 60 mg, respectively, the dechlorination of p-chlorophenol (100 mg/L) followed pseudo-first-order kinetics (rate constant = 0.023 min.sup.-1), and removal efficiency up to 92.5% was obtained in 120 min. The apparent activation energy was 31.6 kJ/mol. The Fe.sub.3O.sub.4@PPY@Pd composite catalyst could be reused without a significant loss in activity. This confirms the good stability of the catalyst. Here, a reductive approach for the dechlorination of organic compounds in water is provided. It is also useful for the fabrication of Pd-based nanocatalysts with easy accessibility, superior activity, and convenient recovery.