The Research On The Removal Of Polycyclic Aromatic Hydrocarbons By Ce³⁺/TiO₂Loaded On The Fly Ash Zeolite Synthesized From Fly Ash

Polycyclic aromatic hydrocarbons，typical persistent organic pollutants（POPs）， canadverse health effects such as muta-genic，carcinogenic and teratogenic properties．Countriesall over the world make strict limits on the levels in the environment．The world healthorganization formulated of benzene in drinking water and [a] pyrene concentration is0.7ug/Lhighest qualityï¼› U．S．EPA determined16kinds of PAHs such as naphthalene benzene and[a] pyrene，fluoranthene for environmental priority control pollutants， the request amount isless than0.2ug/Lï¼› China listed7kinds of PAHs as priority pollutants， the provisions ofbenzene in drinking water and [a] pyrene concentration should be less than0.01ug/L，currentresearch mainly concentrated in the distribution and damage investigation of PAHs in theenvironment， microbial species of degradation of PAHs， the adsorption effect of PAHsbioremediation，materials，etc．It is difficult to effectively remove polycyclic aromatic hydrocarbons in water bytraditional biological or physical and chemical methods，but TiO₂light degradation which canget rid of the PAHs in the water is safe and effective．TiO₂is a kind of N type semiconductormaterials， which has the strong oxidizing and reducing．TiO₂has advantages of highcatalytic activity，strong heat resistance，long duration，low price， and make it one of themost popular a photocatalyst．The conventional TiO₂is powder form although strongphotocatalysis，it is often difficult to using in separation and recovery in wastewater treatmentprocess，so people focous on those researches about how to fix the TiO₂on carriers．Glass，ceramics，activated carbon are the materials which people study a lot，while a number ofresearches using zeolite as TiO₂light catalyst carrier also have been conducted．According toreports in the literature， most studies have choose natural zeolite as the carrier． However，the synthesis of zeolite which can remove organic pollutants do rarely make the newsresearch．At the same time，high temperature roasting is a must by traditional load methodsto obtain the composite photocatalyst，and that equipment complex and more energyconsumption．So，low temperature preparation of TiO₂is also a hot research topic in TiO₂preparation in recent years．Aim at above problems，the main objective of this study is to load TiO₂using the fly ashzeolite synthesized from fly ash as the carrier and tetrabutyl titanate as precursors in lowtemperature （80℃）．In the process of load to improve photocatalytic activity， rare earthcerium ion is doped． To this end， the preparation of the fly ash zeolite load Ce3+/TiO₂ photocatalyst strengthened the removal efficiency for PAHs． In our research，the structure ofthe catalysts was characterized and its degradation characteristics and degradation mechanismwere studied．...