Photocatalytic UV degradation of 2,3,7,8-tetrachlorodibenzofuran in the presence of silver zeolite

Abstract

Silver clusters were introduced into the framework of zeolite Y. Low-temperature solid-state luminescence indicates the formation of silver–silver excimers and exciplexes that were found to be activated at 250 and 300 nm, respectively. The photodegradation of a persistent halogenated organic pollutant, namely 2,3,7,8-tetrachlorodibenzofuran (2,3,7,8-TCDF), was studied in the presence and absence of two catalysts, namely including AgY1 and AgY2, under mid- and high energy: 302 and 254 nm, respectively. The results showed that in the absence of a catalyst, degradation under 254-nm UV light resulted in changes to the peak intensity as well as energy, while the 302-nm profile showed only loss in peak intensity. In the presence of either catalyst, a higher rate of degradation of the 2,3,7,8-TCDF was observed. The amount of the adsorbed 2,3,7,8-TCDF on the AgY1 and AgY2 catalyst was estimated to reach 37.9 and 18.9% of its initial concentration, respectively. The toxicity of the intermediate and resultant products was further analyzed with the aid of an enzyme-linked immunosorbent assay. The optical density showed that in contrast to all the samples, the TCDF irradiated with 254 nm in the presence of AgY2 was high at 40 min inferring a decrease in toxicity of the resultant product. The present work shows an innovative and cost-efficient technique for the removal of dioxins and furans from water sources.