ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Heterogeneous Fenton degradation of azo dye 4BS over Co–Mn–Fe ternary hydrotalcites

Xi Wu, BingBing Luo, Feifei Chen, and Feng Yang

Wuhan Textile University, Wuhan, China

E-mail: chff1977@163.com

Abstract: This work described the application of Co–Mn–Fe hydrotalcites (Co–Mn–Fe LDHs) as heterogeneous catalysts for Fenton reaction process. The Co–Mn–Fe LDHs were synthesized by the co-precipitation method and were characterized by X-ray diffractometry (XRD), infrared spectroscopy (IR), zeta potential, and BET surface area measurement. The catalytic activity of different kinds of hydrotalcites was evaluated by the degradation of Direct Scarlet 4BS (4BS). The Co–Mn–Fe LDHs showed the best catalytic performance among four catalysts. The presence of the Mn²⁺/Mn³⁺ at surface of catalyst could accelerate the reduction of Co³⁺–Co²⁺, and then increased in the catalytic activity of the Co–Mn–Fe LDHs. The effect of initial pH, catalyst dosage, dye concentration, and reaction temperature on the degradation of 4BS had been investigated. Radical reaction mechanism was proposed by the addition of radical scavenger. The degradation kinetic followed pseudo-first-order model. The activation energy of Co–Mn–Fe LDHs was determined to be 37.3 kJ/mol. The catalytic activity of Co–Mn–Fe LDHs was maintained after four cycles of reaction, which proved the reusability of catalyst. Finally, the possible reaction mechanisms involved in the heterogeneous Fenton system were proposed.

Keywords: Co–Mn–Fe ternary hydrotalcites ; Heterogeneous Fenton reaction ; 4BS ; Radical mechanism 

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-018-0489-4

Chemical Papers 72 (10) 2433–2441 (2018)