Advanced Powder Technology, Vol.30, No.1, 126-135, 2019
The fabrication of floating Fe/N co-doped titania/diatomite granule catalyst with enhanced photocatalytic efficiency under visible light irradiation
Powdery photocatalyst has long been studied, yet its several disadvantages such as light-harvesting and recyclability in suspension system are the bottlenecks for practical application. The recent report on floating photocatalyst provided an alternative method to solve the above problem. In this work, TiO2 nanoparticles were co-doped by iron and nitrogen, and then dispersed onto natural porous mineral diatomite via sol-gel method. The composite powder was granulated to produce floating granule catalyst (Fe/N codoped TiO2/diatomite hybrid granule), denoted as FN-TDHG. Its various physicochemical properties such as light absorbance, crystallinity, surface condition as well as morphology were systematically analyzed. The synergy between Fe and N dopants, as well as diatomite and TiO2 were studied. The photoactivity of FN-TDHG was investigated via the degradation towards tetracycline (TC) solution under visible light irradiation, and then the optimal co-doping amount and granule dosage were determined. The optimal granule catalyst presented its removal rate of TC as 96.5% within 150 min. Moreover, floating FN-TDHG could simply be filtrated from the surface of water matrix, and presented good reusability after 5 repetitions. This photocatalytic granule is hopefully considered suitable to be applied in environmental remediation. (C) 2018 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.