Adsorption And Photocatalytic Decomposition Of Oil Using Nanometer Titanium Oxide Modified Exfoliated Graphite

Exfoliated graphite (EG) with, low density, avirulence, good stability andso on shows excellent ability in adsorption of oil. It can not introduce secondpollution in use. Anatase titanium oxide is a kind of materials which is goodat catalysis degradation. So TiO₂-modified EG (EG/TiO₂) is one of newmaterials to solve the oil pollution in water.In this paper, EG and EG/TiO₂ were prepared by sol-gel method,researched with Orthogonal experimental and tested by XRD method, SEM,FT-IR and etc. Synthesis, EG/TiO₂'s adsorption of oil and catalysis abilitywere studied also. Lots of information about EG/TiO₂ was shown, whichsupport possibility of EG/TiO₂'s use in solving oil pollution in water.EG has been prepared in the way of chemcial-oxidization. Prophaseexperiment shows that unit volume has great effect on absorption of oil, so theinfluences of factors on unit volume were studied. It was shown thattemperature plays the most important role, the unit volume of EG keeppositive-going as temperature increase; water wash can make the intercalationescape from graphite layer, and reduce the unit volume. The best level is thattemperature is 1000℃, volume of acid ratio (H₂SO₄:HNO₃) is 1:1, time ofimmersion is 80min and time of washing is 3.With SEM method, wax was used to show process of EG's absorptionand storage of oil, it was shown that the open pores in and on EG supplystorage room for oil, closed pore is useless in adsorption process, meanwhilewhen EG touch oil, they conjunct and create new storage room, this is thereason for absorption.Through sol-gel method, EG was modified by anatase titanium oxidewith grain size of 7-20nm. Catalysis degradation of methyl blue and thesorption of oil of EG/TiO₂ was studied by orthogonal. We discussed influenceof different factors, and the best association is that P(the ratio of TiO₂) is 0.8,time of coating is 1 and roasting time 20min and temperature 400℃.Weight loss method and FT-IR spectrum was used to characterize theoil's degradation ability. In experiment, EG/TiO₂ shows good catalysis ability.The probably reason as follow: in EG/TiO₂, titanium oxide can contact moreoxygen for its three-dimension form, EG can provide enough oil for TiO₂ in catalysis process. In addition, the ultraviolet light can penetrate graphite,which promote the degrade process of TiO₂ coated on EG.