PHOTODEGRADATION OF DYES IN THE PRESENCE OF BISMUTH-TREATED APATITES AS HETEROGENEOUS CATALYSTS IN WATER

In viewpoint of development photocatalyst for water purification based on advanced oxidation process, hydroxyapatite (HAP-400) and fluoraptite (FAP) were treated with Bi(NO3)3 in DMSO/H2O mixed solvent (DMSO = dimethylsufoxide) to give the corresponding Bi-treated apatites, HAP-400-Bi FAP-Bi, respectively. The apatites investigated as catalysts photodegradation dyes, alizarin red S (ARS) methyl orange (MO), under H2O2-absent/present condition. Photodegradation rates ARS H2O2-absent condition reached 73% 83% accompanied adsorption at 62% 69% On other hand, MO was photodegraded less than 4% same condition, possibly attributed little adsorbabilities prepared Bi catalysts. Eventually, by using or FAP-Bi H2O2-present namely photo-Fenton like resulted complete consumption rate 100% both catalysts, considerably high mineralization 40% FAP-Bi. Generation hydroxyl radical •OH an activated oxygen species confirmed following two methods: One employs 2-propanol a scavenger; N, N-dimethylamino-4-nitrosoaniline (DMNA) indirect detector. It found that is predominantly formed via offer oxidative reaction field, self-photodegradation dye, especially ARS, partly proceeds electron transferring interaction between dye catalyst.