Preparation of a new green composite based on chitin biochar and ZnFe2O4 for photo-Fenton degradation of Rhodamine B

Degradation of sulfadiazine in aqueous media by peroxymonosulfate activated with biochar-supported ZnFe2O4 in combination with visible light in an internal loop-lift reactor

“…Some studies have shown that superoxide free radical (˙O 2 − ) is generated through electron transfer to dissolved O 2 . 59,60 Thus, experiments in different atmospheres (N 2 , O 2 , and air) were carried out to confirm the existence and contribution of ˙O 2 − in the Vis/ZnFe/BC/PMS system. The role of O 2 in the degradation of SDZ was investigated by bubbling N 2 or O 2 instead of air in the Vis/ZnFe/BC/PMS system.…”

“…[66][67][68] ZnFe/BC was excited under visible-light irradiation to produce e ℡ and h + (eqn ( 6)). Photogenerated e ℡ in BC were captured by adsorbed O 2 to produce cO 2 À according to eqn (7), 59,60 owing to its more negative CB than that of O 2 /cO 2 À (À0.33 eV). 69,70 The photogenerated e À could easily migrate from the CB of ZnFe 2 O 4 to the h + in the VB of BC and recombine with them.…”

Application of biochar-based photocatalysts for adsorption-(photo)degradation/reduction of environmental contaminants: mechanism, challenges and perspective

“…The electrons were generated and then reacted with O 2 to form •O 2 − free radicals, which facilitated the degradation of MB. Welter et al (2022) prepared ZnFe 2 O 4 /biochar composites and applied them for the degradation of RhB using heterogeneous photo-Fenton processes. Siara et al (2022) applied ZnAl 2 O 4 -biochar for the degradation of ibuprofen, and found that 100% ibuprofen (20 mg/L) was eliminated in 120 min, which was attributed to the high surface area, pore volume and mesoporous size of ZnAl 2 O 4 -biochar.…”

The application of photoelectrocatalysis in the degradation of rhodamine B in aqueous solutions: a review

“…In a study by Welter et al , degradation of rhodamine B was achieved through a photo-Fenton process using a composite of chitin biochar and ZnFe 2 O 4 . 50 This material was prepared using the sol–gel method, and the presence of biochar in the composite promoted efficient charge separation in the ZnFe 2 O 4 . Impressively, after 1 h, 100% discolouration of rhodamine B was achieved in the photo-Fenton process.…”