Synthesis And Properties Of Porous Cordierite Functional Composites

In recent years,cordierite materials has been widely used on filter materials,and catalytic carrier,electronic packaging and other fields.low expansion coefficient,good thermal stability and dielectric constant characteristics of the development of automotive exhaust purification catalyst has become a hot spot of research.Titanium dioxide is a kind of commonly used photocatalyst.N doped TiO₂ extended the range of visible light region,and the photocatalytic efficiency was improved obviously.The nitrogen doped titanium dioxide can be obtained with composite material with photocatalytic and thermal expansion coefficient in porous cordierite.This thesis is divided into three parts:?1?using diameter of about 1 m MF microspheres as template,we synthesis MF microspheres by natural sedimentation of colloidal crystal templating method,precursor immersion colloidal crystal template for several days,the colloidal crystal template and cordierite precursor gel complex can be obtain.At the temperature of 1300?,the colloid crystal template is removed,and the inorganic salt precursor is crystallized into alpha cordierite phase.The effects of the amount of precursor and calcination temperature on the sample,the coefficient of thermal expansion and the porosity were investigated.The research shows that the amount of precursors of 80wt.%,porous cordierite macropores outline clear with uniform pore size;the calcination temperature is 1300?when the main crystal phase of alpha cordierite phase,thermal expansion coefficient is the lowest,1.76×10^-6?^-1;calcination temperature is 1200?to 1300?,the samples show the porosity and kept constant at 69.24%.?2?preparation of nitrogen doped titanium dioxide solution monomer with four butyl titanate and urea.Blend the nitrogen doped titanium dioxide solution into porous cordierite with the aperture of 800nm.We study on the effect of nitrogen doped titanium dioxide on the morphology of composites and the FT-IR and XRD data.The results show that the amount of nitrogen doped titanium dioxide?9wt.%?,nitrogen doped TiO₂ covered on the cordierite surface,porous cordierite is clearly visible;by exploring the nitrogen doped TiO₂-FT-IR peak shows that the expected product was successfully prepared by exploring;nitrogen doped TiO₂ porous cordierite XRD show that has been successfully prepared anatase titanium dioxide,rutile titanium dioxide when the temperature reached 800?.?3?using nitrogen doped TiO₂-dimensional porous cordierite as photocatalyst in the photocatalytic device,analysising light catalytic degradation of methyl orange standard solution,we measured the maximum absorbance with UV spectrophotometry,in accordance with the formula of catalytic degradation rate.The photocatalytic degradation rate of methyl orange and methylene blue was studied under different dosage of nitrogen doped titanium dioxide and calcined at different temperatures.The results showed that the photocatalytic degradation rate of 240min reached the maximum when the amount of nitrogen doped TiO₂ was 9wt.%,and the photocatalytic degradation rate reached the maximum when 240min was 500?.When the calcination time was 2h,the photocatalytic degradation rate of the composites reached the maximum at 240min.