Synthesis of porous Ni/Co LDHs and its degradation behavior for sulfamethoxazole via peroxymonosulfate activation

Abstract

In this paper,nano-Ni/Co hydrotalcite catalysts were synthesized by hydrothermal method using zeolite imidazolate framework materials(ZIFs) as templates, and the physico chemical properties of the catalysts were characterized. With sulfamethoxazole solution as simulated wastewater, the catalytic performance of nano-Ni/Co hydrotalcite to degrade sulfamethoxazole in water via persulfate activation was investigated. Characterization results showed that the catalyst had a nano-rhomboid structure with large pore size and a specific surface area of 187.99 m2/g. The degradation experiment results showed that the removal rate of sulfamethoxazole was about 100% in 20 min, under the conditions of 30 ℃, the concentration of sulfamethoxazole as 15 mg/L, the amount of PMS as 2 g/L, and the amount of Ni/Co hydrotalcite catalyst as 100 mg/L. After reuse of 4 times, the degradation rate of sulfamethoxazole was still greater than 90%, showing its good stability and reusability. Quenching experiments and electron paramagnetic resonance analysis showed that SO4•-, ·OH and 1O2 participated in the degradation reaction. During the reaction process, the redox cycle of Co2+/Co3+ and Ni2+/Ni3+ effectively activated PMS and promoted the generation of active oxide species, which improved the performance of the catalyst for the degradation of sulfamethoxazole.

Keywords

• hydrotalcite
• zeolitic imidazolate frameworks
• peroxymonosulfate
• degradation
• sulfamethoxazole