| Mesoporous alumina materials with highly specific surface area, relatively concentration of the pore size distribution and ordered pore structure has a wide application in the chemical industry, especially as the adsorbent. recent years, the greenhouse effection and heavy metal pollution has become increasingly prominent,the mesoporous alumina as a new material used in CO2capture and adsorption of heavy metal ions attracted the attention of the word scientist. Based on that the main of thesis focus on the alkali (earth) metal functioned MA materials. With the aluminum isopropoxide, aluminum nitrate and aluminum chloride as the aluminum precursor, block copolymers P123and F127as the templating agent, simplely syntheted functioned MA material for the acid gases CO2and heavy Metal pollutant Cr (VI) adsorption.Aluminum isopropoxide as the materials, P123as the template agent, concentrated nitric acid as the acidity regulator, alkali earth metal nitrate as the loading metal precursor, synthesizes functionalized MA materials by the solvent evaporation-induced self-assembly. Using XRD, N2adsorption-desorption, and TEM characterization analyzes the phase composition, textural properties and morphology of the samples. CO2chemical and physical adsorption shows that the MA loadingthe alkaline earth metals show a strong adsorption capacity for CO2at the higher temperature. After the introduction of different amounts of metal material, the surface area, pore size distribution and pore volume was affected, but also have some new basic sites, and enhance the selective adsorption for CO2. Among all of the samples,MA-10Mg shows good results, a strong chemical desorption peak at178℃and600℃, the CO2adsorption capacity is1.13mmol/g, relative to the unfunctional mesoporous alumina0.48mmol/g,235%. CO2adsorption at room temperature mainly depend on the surface of weak alkaline.while the alkaline sites reduce with the degree of the surface area, the unfunctionalized mesoporous alumina with surface area of131.7m2/g, have more CO2adsorption capacity0.9mmol/g.Aluminum nitrate and aluminum chloride as the material,using different template F127and P123, adding alkali metal carbonate as a precipitating agent and load the precursor by solvent evaporation or hydrothermal treatment of the mesoporous alumina precursor, obtained forms of the function of the MA.Using XRD, N2adsorption/desorption and TEM characterization analyzes the phase composition, textural propertiesand morphology of the samples.The prepared samples have large specific surface area and relative concentration of the pore size distribution, with some rules of the channels which is wormlikestructure, meanwhile the samples after the hydrothermal have some fiber rod-likestructure wihe the unhydrothermal massive, the MA FMAc-Na-N preparedc has large specific surface area217.4m2/g, while the FMA-Na-N synthesize by the F127as a template135.4m2/g. The PMAn series of samples prepared by P123as template have smaller surface area th, PMAc-Na-H41.6m2/g and PMAc-Na-N53.0m2/g. The samples after loading the K, FMAc-K-H and PMAc-K-H has a larger adsorption capacity for CO2, which can be achieved1.4mmol/g and1.2mmol/g. In the adsorption of Cr(VI), aluminum chloride, aluminum precursor preparation sample residues more Cl, making the ion exchange reaction of Cr(VI) adsorption process, which FMAc-Na-Nthe concentration of80mg/L Cr(VI) solution at room temperature, pH=3, the adsorption rate can reach90%.On the basis of the MA, the simple process of synthesis of alkaline enhancedcomposite mesoporous materials, explore the metal load, and load the sampleperformance, and improved to some extent, the surface of the base strength of thematerials and alkalinebit density of CO2and Cr (VI) adsorption characteristics on thebasis of experimental data, try to carry out some mechanism on the interpretation ofexperimental results show that the main structure in the case of the maximumguaranteed materials the emergence of some newcharacteristics, provides a new approach to CO2and Cr (VI) adsorption. |
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