Surfactant Assisted Hydrothermal and Thermala2decomposition Synthesis of Alumina Microfibers with Mesoporous Structures

Using template PEG as structure directing agent and urea as the precipitant, alumina microfibers with mesoporous structures were successfully synthesized from a hydrothermal preparation and thermal-decomposition of precursor of ammonium aluminum carbonate hydroxide (denoted as AACH), and its adsorbability was also investigated. The phase state, chemical structure, surface morphology, special surface areas and mesoporous structure of the synthesized alumina microfibers were characterized systemically by means of XRD, SEM, TEM, TG/DTA, and N2 adsoption-desoption techniques, respectively. The adsorptive property of the obtained mesoporous alumina fibers was examined by using a typical SCR(Selective Catalytic Reduction) denitrification facility. The results show that the AACH microfibers with diameter of about 200-300nm and length up to 8| or 10| are prepared by using PEG as template. The mesoporous | Alumina microfibers with specific surface area 316m2/g and average pore diameter 2.5nm are obtained after calcined at 900 or 2h, and the morphology is retained in the calcination process. SCR denitrification tests show that the as-prepared mesoporous alumina microfibers exhibit more favorable adsorptive property and its efficiency of denitrification increases approximately 15% compared with commercial |mAl2O3 powder.