Feizollah Dinarvand - Kashan University of Medical Science, Kashan, Iran.
Nematollah Gaafarzadeh - Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
Mehdi Ahmadi Moghadam - Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.
Mohammad Bagher Miranzadeh - Kashan University of Medical Science, Kashan, Iran.
Nezam Mirzaei - Kashan University of Medical Science, Kashan, Iran.

Introduction and Aims: Compounds containing dye are toxic, carcinogenic and mutagenic for aquatic organisms and lead to mutagenicity, carcinogenicity, and dysfunction of human beings’ kidney, liver, brain, reproductive system and central nervous system. Advanced oxidation processes can remove pollutants faster than other processes due to active hydroxyl radical production. This study was aimed at investigating feasibility of dye removal using UVA/TiO۲ process. Materials and methods: This study was done in a batch reactor and the effects of initial dye concentrations, TiO۲ nanoparticles dosage, time, pH and interference compounds on efficiency of dye degradation was investigated. The Daphnia Magna as bioassay test and biodegradability index (BOD۵/COD rate) were used for detoxification assessment. Results: The D.Y ۵۰ dye effluent degradation at pH ۲, ۲۰ mg/l initial dye concentration and ۱ g/l TiO۲ catalyst was (lnC۰/C= ۱.۴), (lnC۰/C= ۳) and (lnC۰/C= ۲.۹) respectively. Dye removal rate by ۵۰ mg/l COD concentration was (۸۸%), Daphnia Magna mortality rate after maximum contact time (۹۶ h) decreased from ۹۶.۷% to ۴۳.۳% and biodegradability index increased from ۰.۲۵ to ۰.۶۸.

Direct Yellow ۵۰ dye, UV/TiO۲, Photodegradation, bioassay, Daphnia magna