Catalytic degradation of Rhodamine B by steel slag/nitrogen-doped modified activated carbon

Abstract

In order to improve the resource utilization of steel slag and further degrade organic pollutants，a series of steel slag/nitrogen-doped modified activated carbon composites materials were prepared by changing the calcination temperature in ammonia and used to activate sodium persulfate to treat Rhodamine B wastewater. The pore structure and surface properties of the composites were characterized by N2 adsorption/desorption，XRD and XPS. The results showed that the introduction of nitrogen could improve the interaction between active metal and activated carbon in the composites，thus improving the catalytic activity of the composites. With the optimal composite 60%GZ/AC-N800 as the research object，under the condition temperature 35 ℃，2 g/L PS and wide pH（3-11），the removal rate of Rhodamine B（100 mg/L） could reach 88.7%-92.2% after 30 min. The kinetic analysis showed that 60%GZ/AC-N800 composite catalyzed the degradation of RhB by PS in line with the quasi-second-order kinetics. Free radical masking experiments showed that the degradation process was an oxidation process involving both free radical pathways（SO4·- and ·OH） and non-free radical pathways（1O2）.

Keywords

• steel slag
• activated carbon
• nitrogen-doped
• rhodamine b
• persulfate