Study On Effects Of Crystallization And Properties Of Alkali Oxides On Glass-ceramic Of Yellow Phosphorus Slag

We faced the problem of environmental pollution when the phosphate chemical industry development bringing us interests.Yunnan is a important place for phosphate chemical industry.There were large output in yellow phosphorus production process.Due to large phosphorus slag can not be handed in time,the main treatment method was stacking.This method could cause potential danger to environment and human health.At present,the resource utilization of yellow phosphorus slag were applied to cement and concrete admixture industry.But these products had low value.In order to make the yellow phosphorus furnace slag value full play,the high performance glass ceramic was prepared using yellow phosphorus slag.But there were some problems followed,such as high melting temperature,high energy consumption and so on.The high added-value utilization of yellow phosphorus slag was restricted because of these problems.Alkali metal oxide could reduce melting point and have impact on crystallization process of glass ceramic.The crystallization behavior of adding different alkali metal oxide on glass-ceramics were studied.This article used finite element method to determine the best heating rate of nucleation phase and crystallization phase.The purpose of this study was to lower nucleation and crystallization temperature of yellow phosphorus slag basic glass and provide theoretical guidance for optimization of heat treatment process parameters during the preparation of yellow phosphorus furnace slag glass-ceramic.The results showed that:Crystallization activation energy decreased firstly then increased with the increase of K₂O.The crystallization peak temperature and crystallization activation energy were the lowest when the content of K₂O was 3 wt%.The main crystalline phase is wollastonite.Crystallization activation energy decreased with the increase of Na₂O.The micro structure was the best when the content of Na₂O was 5 wt%.And the structure of crystals were kilter and compact.Crystallization activation energy decreased with the increase of Li₂O.The crystallization peak temperature and crystallization activation energy were the lowest when the content of Li₂O was 7 wt%.Wollastonite was the main crystal phase.The calculated results by finite element method showed that:Heating rate?25⁷80??of yellow phosphorus slag basic glass which adding 3 wt%K₂O in nucleation stage should be controlled at 2.65⁵.59?/min.Heating rate?25⁷80??of yellow phosphorus slag basic glass which adding 6 wt%K₂O in nucleation stage should be controlled and 2.55⁵.47?/min.Heating rate?780⁹75??of yellow phosphorus slag basic glass which adding 3 wt%K₂O in crystallization stage should be controlled at 0.84³.95?/min.Heating rate?780⁹75??of yellow phosphorus slag basic glass which adding 6 wt%K₂O in crystallization stage should be controlled at 0.96⁴.54?/min.The results showed that crystals appeared an orderly arrangement.The crystals of yellow phosphorus slag glass-ceramic became ordered and compact in low heat rate of nucleation and crystallization.