Preparation of bead-type NiOx(OH)y catalyst for hypochlorite conversion and reactive brilliant red K-2BP degradation

Publication date: Available online 15 November 2019Source: Journal of Environmental Chemical EngineeringAuthor(s): Wenying Xu, Haoyang GaoAbstractIn order to develop a low-cost NaClO/NiOx(OH)y process instead of Fenton method for treating refractory wastewater, a convenient bead-type hypochlorite conversion NiOx(OH)y catalyst was prepared by simply impregnating Ni-precursor over alumina and then oxidizing with persulfate (PS) in strong alkali solution. The influence of catalyst preparation conditions on the synthesis of NiOx(OH)y was studied. A series of batch experiments were carried out to verify the effective conversion of NaClO and investigate the influence of different parameters. Orthogonal test showed that Ni2+ concentration had the greatest effect on the catalyst performance, while PS dosage had the least effect. The best combination of catalyst preparation parameters is impregnation of the γ-Al2O3 beads in 1.5 M Ni2+ solution followed by oxidation in a mixture of 5% PS and 1.94% NaOH. The best catalyst sample was characterized by XRD, SEM and FTIR. XPS tests showed that the oxygen content in the catalytic layer increased with the Ni2+ solution concentration, and the oxygen content in the catalytic layer with the best performance reached 90.22%. SBET of the samples is 283−292 m2 g-1; Ni(OH)2 accounted for ∼ 2/3 of the nickel content and NiOOH accounted for ∼1/3. The catalyst significantly improved COD and color removal rate of reactive brilliant red (RBR) K...
Source: Journal of Environmental Chemical Engineering - Category: Chemistry Source Type: research