DEGRADATION OF TRICLOSAN BY PHOTO-FENTON OXIDATION

Öz

Triclosan is one of the most used active ingredients in antibacterial personal care products and its usage increased in recent years. Triclosan has recently attracted the attention researchers from the fields of water treatment due to its existence in water environments. This study has been executed to investigate the removal of triclosan with photo-Fenton process and to observe by-product formation after oxidation. Effects of operational parameters namely the concentrations of Triclosan, H2O2 and Fe(II) on oxidation of triclosan were investigated by using Box-Behnken statistical experiment design and the surface response analysis. It was found that the triclosan concentration has a more profound effect than H2O2 and Fe(II) concentrations for removal of triclosan in the aqueous solution. Complete removal of triclosan was accomplished within a hour, however, complete mineralization was not occurred even within sixty minutes indicating formation of some intermediate compounds such as 2,4-Dichlorophenol and 2,4,6-Trichlorophenol. Optimal H2O2/Fe(II)/TCS ratio resulting by maximum triclosan removal (98.5%) was found to be 50/2/0.1, respectively

Anahtar Kelimeler

• Box-Behnken design, Photo-Fenton process, Triclosan

TRİKLOSANIN FOTO-FENTON OKSİDASYON YÖNTEMİ İLE PARÇALANMASI

Öz

Triklosan, antibakteriyel kişisel bakım ürünlerinde en çok kullanılan aktif maddelerden biridir ve son yıllarda kullanımı artmıştır. Bu çalışmada, triklosanın foto-Fenton yöntemi ile arıtılması ve yan ürünlerinin oluşumu araştırılmıştır. Triklosan, H2O2 ve Fe(II) konsantrasyonlarının triklosan giderimine olan etkileri, Box-Behnken istatistiksel deney tasarımı ve yüzey cevabı analizi kullanılarak araştırılmıştır. Triklosan derişiminin triklosan gideriminde H2O2 ve Fe(II) derişimlerinden daha etkin olduğu gözlenmiştir. Triklosan'ın tamamen parçalanması bir saatte gerçekleşirken tamamen mineralizasyonu gerçekleşmemiştir. 2,4Diklorofenol ve 2,4,6-Triklorofenol gibi bazı ara bileşiklerin oluştuğu gözlenmiştir. Foto-Fenton prosesinde, en yüksek triklosan giderimi (%98.5) için H2O2/Fe(II)/TCS oranının 50/2/0.1 olduğu saptanmıştır

Anahtar Kelimeler

• Box-Behnken yöntemi, Foto-Fenton prosesi, Triklosan

Kaynakça

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