Acta Phys. -Chim. Sin. ›› 2013, Vol. 29 ›› Issue (11): 2429-2436.

• CATALYSIS AND SURFACE SCIENCE •

Synthesis of Fe-Al Pillared Bentonite and Heterogeneous Fenton Degradation of Orange Ⅱ

WAN Dong, WANG Guang-Hua, LI Wen-Bing, CHEN Kun, SHU Guang

1. College of Chemical Engineering and Technology, Wuhan University of Science and Technology, Wuhan 430081, P. R. China
• Received:2013-07-11 Revised:2013-10-07 Published:2013-10-30
• Contact: WANG Guang-Hua, LI Wen-Bing E-mail:wghuah@21cn.com; liwenbing@126.com
• Supported by:

The project was supported by the Specialized Research Fund for the Doctoral Program of Higher Education of China (20114219110002), Hubei Key Laboratory of Coal Conversion and New Carbon Materials (Wuhan University of Science and Technology), China (WKDM201107), and Educational Commission of Hubei Province, China (D20131107).

Abstract:

A series of Fe-Al pillared bentonites with different Fe contents were synthesized through a simple ion exchange method. The samples were used as catalysts for the heterogeneous Fenton degradation of Orange II. The microstructure of the catalysts was characterized by X-ray diffraction (XRD), specific surface area measurements (SBET), Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, and scanning electron microscopy (SEM). The obtained results showed that the pillaring process increased the basal spacing (d(001)) from 1.24 nm for the Na-bentonite (Bent) to 1.77 nm for the Al-Bent and ~1.72 nm for the Fe-Al pillared bentonites. The SBET values of the samples were increased after pillaring. It was obvious from the XRD and Raman results that intercalation was not achieved and that hematite was formed in the 20Fe-Al-Bent sample. The influence of Fe content on the degradation of Orange II was investigated. The catalytic activity of pillared bentonites increased with Fe content and hardly increased when the molar ratio of Fe/(Al + Fe) in the pillaring solution exceeded 10% . The decolorization efficiency and chemical oxygen demand (CODCr) removal of Orange II reached 100% and 87.73%, respectively, after 4 h oxidation reaction using the 10Fe-Al-Bent sample. It is also proved that the whole decomposition of Orange II by 10Fe-Al-Bent was dominated by heterogeneous Fenton reaction. The catalysts were chemically stable and reusable, with low release of iron.

MSC2000:

• O643