The structure of copper ferrite prepared by five methods and its catalytic activity on lignin oxidative degradation

Abstract

Effects of copper ferrites with different prepared methods on the catalytic degradation of lignin with hydrogen peroxide as oxidant is studied. The microstructure, spectral properties and magnetic properties of copper ferrites prepared with five methods were characterized. The results showed that the microcosmic appearance of the catalysts prepared by the five methods was nanoparticles or irregular blocks. All the samples have strong magnetic properties. However the magnetic saturation intensity, residual magnetic intensity and coercivity of copper ferrite prepared by different methods are distinct. The degradation rate and the content of benzene-ring substances were the highest when lignin decomposed under the catalyst of copper ferrite prepared by ethylene glycol assisted sol-gel process, while the content of open-ring substances was the highest when lignin decomposed under the catalyst of copper ferrite made by co-precipitation. Compared with Fenton catalyst, The copper ferrite catalyst easily be separated and good repetitive catalytic performance when used in the lignin degradation. In addition, the crystal structure of copper ferrite play an important role on the catalytic degradation properties of lignin.