Electrochemical properties of gel-type zeolite synthesis mixtures

Abstract

The variation of the potential difference of two electrodes, connected by a voltmeter and immersed into different gel mixtures yielding various zeolites, was observed with respect to synthesis time. The potential difference-time curves obtained for zeolites such as X, A, and HS exhibited characteristic behaviors that might be helpful in their identification. These behaviors could be rationalized by taking into consideration the changes occurring mainly in the dissolved sodium and aluminum concentrations of the liquid phase, before and during the crystallization of zeolites. The relative rates of zeolite crystallization were also reflected on the potential difference-time curves. Reaction mixture compositions with relatively low Si/Al ratios generally led to sharper changes in the potential difference, due to the relatively high crystallization rates obtained in these cases.