Catalytic efficiency and stability of cobalt hydroxide for decomposition of ozone and p-chloronitrobenzene in water

Abstract

Cobalt hydroxide, a stable and efficient catalyst prepared in the laboratory, has been successfully used in the decomposition of ozone and trace quantities of p-chloronitrobenzene (pCNB) in water. The cobalt hydroxide was characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM) and the Brunauer-Emmet-Teller (BET) method. The decomposition rate of aqueous ozone was increased by 1.527 times in the presence of cobalt hydroxide. Increasing the catalyst loading from 0 to 500 mg/L increased the removal efficiency of pCNB from 59% to 99%. The catalyst morphology and its composition were found to be unaltered after the catalytic reaction.After five successive recycles, the catalyst remained stable in the catalytic ozonation of pCNB.

Role of Fe/pumice composition and structure in promoting ozonation reactions

“…The considerably low reactivity of p-CNB towards biodegradation makes it harmful to aquatic environments. In addition, p-CNB is difficult to remove using chemical oxidation and has low adsorption onto solid surfaces [20,[27][28][29]. Therefore, p-CNB was a well suited model pollutant for catalytic ozonation testing.…”

“…The compound p-chloronitrobenzene (p-CNB) is a typical halogenated nitro-aromatic compound extensively used in many fields and detected in natural water [27]. The considerably low reactivity of p-CNB towards biodegradation makes it harmful to aquatic environments.…”

Deposition of β-Co(OH)2 Films by Electrochemical Reduction of Tris(ethylenediamine)cobalt(III) in Alkaline Solution

“…It is also an active catalyst for ozone and p-chloronitrobenzene decomposition in water. 5 In addition, Co(OH) 2 exhibits the giant reversible magnetocaloric effect, which makes it a promising candidate for low-temperature magnetic refrigeration applications. 6 Co(OH) 2 can be oxidized electrochemically 1,4 to CoOOH, which is an excellent oxygen evolution reaction (OER) catalyst, 4,7 and it is used in room temperature CO sensors.…”

“…Co(OH) 2 is known as an earth-abundant catalyst for the oxygen reduction and hydrogen evolution reactions. It is also an active catalyst for ozone and p -chloronitrobenzene decomposition in water . In addition, Co(OH) 2 exhibits the giant reversible magnetocaloric effect, which makes it a promising candidate for low-temperature magnetic refrigeration applications .…”

Decomposition of high-level ozone under high humidity over Mn–Fe catalyst: The influence of iron precursors

“…Among them, catalytic decomposition is the most widely used method, due to its advantages of mild reaction conditions, high efficiency and low cost. Numerous catalysts have been investigated, including transition metal oxides [14][15][16][17][18][19][20][21], activated carbon [22,23] and noble metals [24][25][26]. Among these catalysts, manganese oxides (MnO x ) usually show good catalytic performance in ozone decomposition.…”