Synthesis And Properties Of Fe-SBA-15 Mesoporous Materials From Iron Tailings

SBA-15 mesoporous molecular sieve has a large specific surface area,high hydrothermal stability,uniform pore diameter distribution?pore size can be adjusted?,good catalytic stability and adsorption separation characteristics,and has broad application prospects in the field of biology and nano materials.In this paper,iron tailings were used as raw materials,and the iron salt solution and Na2SiO3 solution prepared by mineral chemical treatment were used as cheap iron source and silicon source.Synthesis of Si-SBA-15 and Fe-SBA-15 by hydrothermal synthesis is used P123 as template;X-ray,SEM,Fourier transform infrared spectroscopy?FT-IR?,UV-visible diffuse reflectance spectroscopy?UV-Vis DRS?,N₂isotherm adsorption-desorption method are used for the synthesis of mesoporous molecular sieves analytical characterization;adsorption properties and photocatalytic degradation properties of Si-SBA-15 and Fe-SBA-15 mesoporous molecular sieves were investigated with methylene blue as the research object.The sodium silicate solution prepared from iron tailings is used as a silicon source,and acidity is provided by HCl.The Si-SBA-15 mesoporous molecular sieve without metal modification is synthesized by direct synthesis.The results show that when the acid concentration is 2 mol/L,the ratio of templating agent P123 to silicon is 1:0.09,and the hydrothermal crystallization time is 72 h,the prepared SBA-15 molecular sieve has a specific surface area of 685 m²/g and a pore diameter of 11.5 nm.The Fe modified SBA-15 mesoporous molecular sieve can be directly synthesized by using the strong acidic environment generated in the acid leaching process without any inorganic acid.With the increase of iron doping amount,the order of molecular sieves decreases;the Fe-SBA-15 pores with Fe/Si of 0.01 have higher order,while the Fe-SBA-15 with Fe/Si of 0.2 has larger Specific surface area 614 m²/g and smaller pore size 7.5 nm.Both Si-SBA-15 and Fe-SBA-15 mesoporous molecular sieve have good adsorption properties for methylene blue solution.The results show that the undoped Si-SBA-15 with larger specific surface area shows good adsorption performance and the adsorption efficiency reaches 99%;while the adsorption efficiency of Fe-SBA-15with Fe/Si of 0.2 is 82%.Fe-SBA-15 mesoporous molecular sieve has good photocatalytic properties.In the initial photocatalytic reaction of methylene blue solution,the concentration was 10mg/L,the photoreaction time was 60 min,and the Fe-SBA-15 mesoporous molecular sieve had a Fe/Si concentration of 0.1 at 0.6 g/L.The photodegradation efficiency reached 83%.