Effective removal of Orange II dye by porous Fe-base amorphous/Cu bimetallic composite

Azo dye wastewater is a worldwide problem with substantial deleterious environmental effects. Fe-based amorphous alloys have shown potential in azo dye wastewater treatment. However, their slower degradation rate and narrow working pH range hinder their wide application. Therefore, we designed a new porous Fe-base amorphous/Cu (Fe-am/Cu) bimetallic composite ribbon and prepared them using the chemical replacement copper plating method to remove the Orange II dye. The designed bimetallic composite ribbons can enhance the removal rate of azo dyes to various extents. The kinetic reduction rate (k(obs)) of the porous Fe-am/Cu bimetallic composite is 0.217 min(-1) at pH= 7, a 92 % improvement compared to the k(obs) of Fe-am. Moreover, the porous Fe-am/Cu bimetallic composite shows a more comprehensive adaptability range of pH = 3-11 compared with many Fe-based amorphous catalysts. During kinetic analyses, the decolorization rates fitted well with both the pseudo-first-order reduction and pseudo-second-order adsorption models, implying that the removal of Orange II by porous Fe-am/Cu bimetallic composite involves both adsorption and catalytic modes of reduction. The strategy using the chemical replacement copper plating method to obtain porous Fe-am/Cu bimetallic composite is simple, cost-effective, and environmentally benign, making the large-scale production of porous Fe-am/Cu bimetallic composite possible for field remediation.

Automated summary

A new porous Fe-base amorphous/Cu (Fe-am/Cu) bimetallic composite ribbon was prepared using the chemical replacement copper plating method, which showed promising potential in removing Orange II dye. The designed bimetallic composite ribbons can enhance the removal rate of azo dyes and have a wider adaptability range of pH compared to many Fe-based amorphous catalysts.