Study On Preparation Of TiO₂/CB-FC Materials And Its Enrichment And Degradation Of BTEX

With the rapid development of chemical industry, BTEX leakage accidents occurred frequently in China, and large amount of organic waste water were generated. If there is no harmless treatment of the organic wastewater, it would cause a greater threat to the ecological environment security. The concepts of photocatalytic degradation and adsorption were combined in this study, in order to prepare a composite material with enrichment and degradation. The composite materials could concentrate BTEX in a short time and prevent the generation and transmission of toxic gases effectively. So the problem of environmental security risks and rescue measures defect would be sovled.In this paper, foam carbon materials were prepared by template method using rice husk carbon as carbon source, corn starch as binder and polyurethane for template carbon foams.CB-FC materials were prepared by biomass hydrothermal method using foam carbon and glucose as raw materials. The composite material TiO₂ and TiO₂/CB-FC were prepared by sol gel - hydrothermal method using four butyl titanate as titanium source and CB-FC as carbon source. The composite material TiO₂-?CB-FC? was prepared by mechanical mixing method. SEM?XRD?FT-IR?BET and determination of bulk density were used for materials characterization, such as morphology, crystal structure, functional group structure, specific surface area of the products and separation characteristics. Adsorption and degradation of benzene and toluene in aqueous phase were tested,and the adsorption mechanism of CB-FC and the degradation mechanism of TiO₂/CB-FC were described respectively.Specific research contents are follows:CB-FC materials were prepared by biomass hydrothermal method. The results showed that ?1?foam carbon has a well-developed pore structure, carbon balls mainly concentrated in the surface and large pores of foam carbon,the average size of carbon spheres were 2?3?m, and there is no cluster phenomenon. ?2?XRD picture showed that CB-FC wasamorphous carbon, and carbon balls did not affect the crystalline structure of foam carbon.?3? CB-FC were mainly composed of mesopores and micropores. The presence of carbon spheres increased surface area of micropores and reduced surface area of pores. ?4? The adsorption capacity of CB-FC composites on benzene and toluene in aqueous solution increased by 25% and 40% respectively, which played a role in enriching BTEX.The composite materials TiO₂ and TiO₂/CB-FC were prepared by sol gel hydrothermal method. The results showed that ?1? TiO₂ and TiO₂/CB-FC were anatase TiO₂, the average crystal size was 10.05nm, and the addition of CB-FC did not affect the crystal structure and crystallite size of TiO₂. ?2? The interface between TiO₂ and CB-FC had the formation of Ti-O-C bond, and with the addition of FC-CB, the bonding was more stable. ?3? After 3 hour irradiation, the removal rate of benzene and toluene were all TiO₂/10%?CB-FC?>P25>TiO₂/25%?CB-FC?>TiO₂/5%?CB-FC?>TiO₂, the degradation rate of benzene and toluene by TiO₂/10%?CB-FC? reached 90% and 95%, the degradation effect is better than that of P25. The composite material TiO₂/10%?CB-FC? has the characteristics of high activity, easy separation and reusable which have great potential application in wastewater treatment.The composite material TiO₂-?CB-FC? was prepared by mechanical mixing method.The results showed that ?1? TiO₂-10% ?CB-FC? was anatase TiO₂. ?2? There was a kind of physical bonding between TiO₂ and CB-FC's interface instead of Ti-O-C bond. ?3? After 3 hour of UV irradiation, the removal efficiency of TiO₂-10%?CB-FC? composites prepared by mechanical mixing method was inferior to TiO₂/10% ?CB-FC? prepared by sol-gel hydrothermal method.