Ultrasonic-enhanced nascent H<sub>2</sub> activation on Raney Ni for the degradation of triclosan

Applicability of Nickel-Based Catalytic Systems for Hydrodehalogenation of Recalcitrant Halogenated Aromatic Compounds

“…Wang et al reported an increase in the HDH rate using ultrasonic action on triclosan catalyzed by Raney Ni saturated with gaseous H2 [85].…”

“…It was observed that Raney Al-Ni alloy is, especially in diluted aq. NaOH or KOH, a very effective and universal HDH agent enabling quantitative HDH of Ar-Br, Ar-Cl compounds at elevated temperature [89,90,95,96,99,102,104] or even at room temperature [81][82][83][84][85][86][87][88][89][90][91][92][93][94]98,103].…”

“…Ma et al published a smooth HDH of chlorophenols with H2 in an alkaline aqueous solution using suspension of the Raney nickel catalyst[84]. The used Ra-Ni is recyclable 5-times without loss of HDC activity.Wang et al reported an increase in the HDH rate using ultrasonic action on triclosan catalyzed by Raney Ni saturated with gaseous H2[85].Raut et al published effective HDC of 4-chlorophenol (30 mg/L) caused by a high excess of Raney Ni (3 g/L) in an aqueous solution by co-action of trialkyl amines (45 mg/L) without the addition of other reductants[86]. The observed HDC was explained by the partial dissolution of Raney Ni in an aqueous trialkylamine solution with subsequent H2 formation which adsorbed on catalytically active nickel sponge and caused HDC of 4chlorophenol (Scheme 18).…”