Preparation And Adsorption Properties Of SBA-16 Magnetic Mesoporous Materials

The SBA-16 mesoporous molecular sieve material has the advantages of large diameter,large specific surface area,easy modification and good thermal stability,and has great application prospect in the fields of catalysis,biomedicine and adsorption.The magnetic material Fe₃O₄ has strong saturation magnetization and high coercivity,which is precisely what the mesoporous molecular sieve does not possess.Combined the advantages of both,to grow SBA-16 molecular sieve on the Fe₃O₄ particles,preparation of core-shell type Fe₃O₄@SBA-16 nano magnetic materials,maintain the advantages of magnetic material itself and the influence of the molecular sieve SBA-16 is lesser also.The main work of this paper is as follows:1,By hydrothermal synthesis method,adopts double template agent P123,SBA-16 F127 preparation of mesoporous molecular sieves,mole ratio of change in the process of preparation of template agent,crystallization temperature,the study of molecular sieve SBA-16 properties and morphology.The surface area was prepared between 379.5484⁷46.9434m²/g,and the pore volume was between 0.3885⁰.6905ml/g,and the aperture was between 3.47⁵.89nm and SBA-16 molecular sieve.In this paper,the effect of crystallization temperature on the properties and morphology of the samples was found by adjusting the molar ratio and crystallization temperature.The crystallization temperature is too low or too high,the sample is lower than the surface area;The crystallization temperature is too low and the sample is irregular.When the molar ratio of F127 and P123 is 1.95,the crystallization temperature is110℃when the sample specific surface area of 746.9434 m²/g,at this time the sample specific surface area,the largest adsorption performance is best.2,By hydrothermal synthesis method,using a single template agent F127,n-butyl alcohol preparation of molecular sieve SBA-16,respectively,to change in the process of preparation of n-butyl alcohol dosage and the crystallization temperature,the study of molecular sieve SBA-16 properties and morphology.The surface area was prepared between 704.4207¹007.5356 m²/g,and the pore volume was between0.4428¹.1217 ml/g,and the aperture was between 3.53³.85nm and SBA-16molecular sieve.We found that when the dosage of n-butanol was 4g,the specific surface area of the sample was the largest,the adsorption performance was the best,and the microstructure was the spherical morphology of the uniform one.When the crystallization temperature rise slowly,the specific surface area increases,when the crystallization temperature of 110℃maximum specific surface area and pore volume.When the dosage of n-butyl alcohol is 4g,crystallization temperature is 110℃when the specific surface area and pore volume is the largest.3.Using hydrothermal synthesis method to wrap a layer of ordered mesoporous silica on the surface of magnetic particle Fe₃O₄ to form magnetic composite materials with magnetic nanoparticles as nuclei.The optimum solution in the preparation of pure phase SBA-16 was used to change the dosage of Fe₃O₄ and to study the morphology and performance of composite materials.The specific surface area was prepared between 590.6180⁷56.6838 m2/g,and the pore volume was between0.4438⁰.8155 ml/g,and the pore diameter was between 3.73⁴.01nm and the Fe₃O₄@SBA-16 nano-magnetic composite material.We can prepare magnetic composite materials when the amount of trioxide is 0.5g,1.0g and 1.5g.It can be seen from the XRD graph that with the increase of Fe₃O₄ dosage,the characteristic peak of SBA-16is weakening,and the characteristic peak of Fe₃O₄ is getting stronger and stronger.When the dosage of Fe₃O₄ was increased,the specific surface area of Fe₃O₄@SBA-16 nano-magnetic composite was decreased.Although Fe₃O₄@SBA-16nanometer magnetic composite material increases with the increase of the amount of Fe₃O₄,however,it is analyzed by SEM test.When Fe₃O₄ dosage is 1.5g,there are some Fe₃O₄ uncoated.Therefore,when Fe₃O₄ dosage is 1.0g,the optimum conditions for preparing Fe₃O₄@SBA-16 nano-magnetic composite materials are prepared.