Effect of trace Ag+ adsorption on degradation of organic dye wastes

By the introduction of Ag+, the molecular imprinting technology and photocatalysis technology were associated with each other and the Ag+-imprinted biosorbent (Ag-IB) was prepared. Ag-IB could first adsorb Ag+ and then degraded Methyl Orange (MO). Firstly the influences of the ionic strength and pH value in solution on adsorption capacity for Ag+ were studied, and then the effects of Ag+ adsorption capacity on degradability for MO were investigated. The maximal degradation ratio of MO reached over 93% at Ag+ adsorption capacity of 78.0 mg/g after 5.0 h. In contrast to MO, Methylene Blue (MB) and Sunset Yellow (SY) were studied and the degradation ratios could be about 70% and 98% at Ag+ adsorption capacity of 36.9 mg/g, respectively. And XPS analysis showed that Ag+ was reduced to Ag on Ag-IB surface. Furthermore, the mechanism for photocatalytic degradation of MO dye was primarily researched.