Preparation Of Colored Active Carbon

Colored active carbon was prepared by spray pigment suspension on coconut shell active carbon and columnar active carbon. N2 adsorption-desorption isotherm were used to characterize the pore structure of the obtained samples. The color of the samples was described by compare with standard color card of GSB05-1426-2001. The removal rate of toluene or that of the mixture of toluene and benzene in 1 h was used to characterize the adsorption ability of the prepared colored samples.The results were as follows:Spraying Polyethylene emulsion (PE) on the surface of active carbon can not only improve the gloss of the samples, but also resist the carbon dusts efficiently.The black color make it difficult to color active carbon directly, P-25 suspension was first spray on the surface of active carbon to make it turn to light blue. Then other pigments suspension, such as phthalocyanine blue, phthalocyanine green, benzidine yellow and Fe2O3, were sprayed on the light color precursor. Thus, colored active carbon was prepared.The BET specific surface area of the precursor was related to the concentration of P-25 suspension. The result showed that the lower concentration was benefit to resisting the decrease of surface area.The result showed that with the increasing of the pigments usage, the adsorption ability of the samples decreased. Besides, with the increasing of PE concentration being used, the toluene removal rate decreased. The reason is that there were more pigments or PE block the pores of the active carbon, which resist the toluene adsorption. The result is agree with the result of N2 adsorption-desorption analysis. The BET specific surface also reduced with the increasing of pigment usage and the PE concentration of the spray suspension. However, the increasing of pigment usage was benefit for coloring the active carbon, and high PE concentration can make the sample glossy. Therefore, once the color meets the requirements, the pigment usage and the PE concentration of the spray suspension should be minimized.In addition, a series of colored active carbon were prepared by the spray method, using complex pigments and pearlescent pigments. The BET specific surface was at the range of 820 m/g～970 m2/g. The toluene removal rate was from 43% to 74%, as well as the benzene removal rate was at the range of 67%～85%. The specific surface area and pore volume of the samples prepared by pearlescent pigments were higher, but the adsorption ability was lower.Column active carbon was used as starting materials to prepare the colored column active carbon. The BET specific surface was at the range of 560 m2/g～790 m2/g. The toluene removal rate was from 45%～57%, as well as the benzene removal rate was at the range of 31%～55%.TiO2 hollow spheres were synthesized by combined acid catalytic hydrolysis-hydrothermal method. TiO2 precursor was deposited on the surface of carbon spheres obtained by hydrothermal method using glucose as starting material. SEM, TEM, XPS, XRD and N2 adsorption-desorption were used to characterize the samples. TiO2 hollow spheres were obtained by calcination under atmosphere after the core carbon sphere was burnt off and TiO2 precursor transforms from uncrystalline to anatase simultaneously. The results revealed that the size and surface morphology of TiO2 hollow spheres can be controlled by adjusting the concentration of glucose aqueous solution. With the increasing of concentration of glucose solution, the diameter of TiO2 hollow sphere increased. The photocatalytic activity of TiO2 hollow sphere was higher than TiO2 made by the same method without using template (TiO2-Go). The phenol removal rate of the sample prepared by calcination at 600℃is as 1.35 times high as that of TiO2-G0.The TiO2 hollow spheres suspension was sprayed on coconut shell active carbon. SEM and N2 adsorption-desorption were used to characterize the samples. The morphology of the TiO2 hollow spheres has not been broken by this spray method and the BET specific surface reduced by 25.21%.