عنوان مقاله [English]
Silica is the most used support for high-performance liquid chromatography columns. Mesoporous silica has attracted much attention due to its properties. Columns with spherical shaped mesoporous silica particles are superior for chromatographic applications because they provide higher efficiency and lower back-pressure compared to irregular particles. In this work, mesoporous silica microspheres were prepared via a two-step synthesis process by using tetraethyl orthosilicate, amphiphilic triblock copolymer, cetyltrimethylammonium bromide, and ethanol. To obtain mesoporous silica spheres with mean particle size about 5.5 μm )obtained by scanning electron microscopy), specific surface area about 670 m2/g and pore diameter about 7 nm )obtained by N2 adsorption-desorption), parameters of synthesis were optimized. After surface functionalization with C18 )about 21% C, obtained by elemental analysis), they were slurry packed into a column )25 cm × 4.0 mm i.d.) and used for separation of alkylbenzenes containing 1-5 carbons, polycyclic aromatic hydrocarbons, and pyridine derivatives mixtures. Phenol and pyridine mixture were used for investigation of active silanols. The synthesized C18-modified mesoporous silica microspheres showed good, repeatable and stable results for separation of above compounds. Among them, the highest efficiency of the column is for benzene with 1484 theoretical plates. Resolutions of copmounds are between 1 and 4. According to tailing factors, peaks are almost symmetric, except pyridine derivatives that show a little tailing.