Coal fly ash supported Co3O4 catalysts for phenol degradation using peroxymonosulfate

Abstract

Several fly ash (FA) samples derived from Australian (FA-WA) and Brazilian coals (FA-JL and FA-CH) were used as supports to prepare Co oxide (Co)-based catalysts. These Co/FA catalysts were tested in peroxymonosulfate activation for sulphate radical generation and phenol degradation in aqueous solution. The physicochemical properties of FA supports and Co/FA catalysts were characterised by N 2 adsorption, X-ray diffraction (XRD), scanning electron microscopy coupling with energy dispersive spectroscopy (SEM-EDS), elemental mapping, and UV-vis diffuse reflectance spectroscopy. It was found that the FA supports did not show adsorption of phenol and could not activate peroxymonosulfate for sulphate radical generation. However, fly ash supported Co oxide catalysts (Co/FA) presented higher activities in the activation of peroxymonosulfate for phenol degradation than bulk Co oxide and their activities varied depending on the properties of the fly ash supports. Co/FA-JL showed the highest activity while Co/FA-WA showed the lowest. Activation energies of phenol degradation on three Co/FA catalysts were obtained to be 47.0, 56.5, 56.0 kJ mol 21 for Co/FA-WA, Co/FA-JL and Co/FA-CH, respectively.

Effect of Process Parameters on the Photocatalytic Degradation of Phenol in Oilfield Produced Wastewater using ZnO/Fe2O3 Nanocomposites.

“…Phenol degradation was 68.3%, 57.8%, and 48.9% after 180 mins using at 0.5, 2, and 3 mg/L initial phenol concentration. Muhammad et al [28] reported that a higher phenol concentration often leads to low phenol degradation efficiency which is in agreement with trend obtained in this study. The present study is consistent with that of Paul et al [29] who reported that g-C3N4 photocatalyst at various loading significantly influences the photodegradation of methylene blue in contaminated water.…”

Preparation Of ZnO/Co3O4 Hollow Microsphere By Pollen‐biological Template And Its Application In Photocatalytic Degradation

“…As shown in Figure , the three tangent lines are extrapolated to get E g1 (Co 3 O 4 , 1.84 eV), E g2 (Co 3 O 4 , 2.89 eV) and E g3 (ZnO, 3.58 eV) values of ZnO/Co 3 O 4 microsphere. The bandgap energy of 1.84 eV is the charge transfer from O 2− to Co 2+ , while 2.89 eV is derived from the charge transfer from O 2− to Co 3+ . It can be seen that doping Co 3 O 4 broadens the photoresponse range of ZnO, resulting in enhanced photodegradation efficiency via electron transfer.…”

Heterogeneous biochars from agriculture residues and coal fly ash for the removal of heavy metals from coking wastewater

“…26 Coal y ash (FA) contains many similar catalytic "ingredients" to such clays, including Al 2 O 3 , Fe 2 O 3 , K 2 O, CaO, MgO, Na 2 O, oen supported on an SiO 2 matrix. 42 Over 100 million tons of FA, the result of coal-burning in power stations and other industrial sources, 43 are produced annually. Much of this FA is deposited in containment ponds, posing health, safety and environmental risks.…”