摘要
研究了一种由粉煤灰合成纯沸石分子筛的新工艺,粉煤灰与碳酸钠混合焙烧生成硅酸钠和硅铝酸钠,用少量水浸取其中的硅酸钠,含硅铝酸钠的残余物用碱液浸取。实验发现,在碱溶过程中溶液中的硅铝存在过饱和现象,在过饱和期内实现固液分离,可提取粉煤灰中的硅铝用于合成X型、A型、P型纯沸石产品。1kg粉煤灰合成310~560g纯沸石。晶化导向剂和晶种对沸石晶型和晶化时间有很大影响。经仪器和化学分析方法对沸石产品从矿物组成和阳离子交换容量进行表征,制得产品的阳离子交换容量可达3.2~4.7meq/g,纯度较高。
In the method presented here, the activity of silicon and aluminum in coal fly ash was stimulated by calcination with sodium carbonate. The calcined product was treated by a method involving a desilication and hydrothermal process, and the silicon and aluminum eluted from coal fly ash was used for the synthesis of pure X, A, P type zeolites. Crystallization directing agents or crystal seeds have a promoting effect on the type of crystallization achieved. The products have been characterized in terms of mineralogical composition and cation exchange capacity (CEC). The results show that the pure zeolites exhibit high cation exchange capacities ranged from 3.2 to 4.7meq/g, and th.e yield from 310 to 560 g/ kg coal fly ash.
出处
《硅酸盐通报》
CAS
CSCD
北大核心
2007年第1期19-24,共6页
Bulletin of the Chinese Ceramic Society
基金
北京市自然科学基金资助项目(No.8042015)
关键词
水热合成
纯沸石
阳离子交换容量
hydrothermal synthesis
pure zeolites
cation exchange capacity