INFLUENCE OF CRYSTALLIZATION TEMPERATURE ON THE ABSORPTION OF DIBUTYL PHTHALATE IN ZEOLITE A
In order to determine the effect of crystallization temperature on the absorption and properties of zeolite A particles, we have monitored the modified dibutyl phthalate absorption ( DBP ), a degree of crystalline phase, specific surface area, mean diameter of particle ( DS50 % ), and performed scanning electron microscopy ( SEM ) of the synthesized samples of zeolites. The synthesis of samples was carried out at crystallization temperatures of 70, 75, 80, 85 and 90°C ; the raw materials (sodium aluminate and sodium silicate) were heated at 90°C. The particle size of the synthesized samples is similar in most studied systems at all temperatures of crystallization, which is in accordance with the principles of the autocatalytic nucleation and „memory effect” of the gel. An increase in the specific surface area of the synthesized samples with the increase in the crystallization temperature was observed in all the analyzed systems (3.25 to 35.31 m2/g). It was found that the increase of crystallization temperature increases the absorption of dibutyl phthalate(0.90-1.20 cm3/g ); however, at the same time, the proportion of zeolite A in the same samples is reduced, as confirmed by SEM analysis.
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