Realuminating solution, effect

Contact Time. Table HI shows that realumination initially proceeds very fast. 67% of the non-framework aluminium goes back into the framework during the first hour of contact with aqueous solution of KOH. In general, increasing the time of contact while other parameters are kept constant has little effect on the extent of realumination as indicated by the small decrease of the Si/Al ratio of the framework (from 2.80 to 2.72) after the length of treatment was increased from 4 to 24 hours. 

Table VI. The effect of the kind of base on the extent of realumination of sample USY. 0.25M aqueous solution was used at 80°C for 24 hours.

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