Al2O3-P2O5-H2O反应体系产物以及高温产物的光谱特征

以磷酸和氢氧化铝为原料,选取不同工艺合成了系列磷酸铝。用FTIR,XRD,Raman和SEM研究了相关产物阴离子基团的红外图谱变化和三聚磷酸二氢铝的热变化过程的光谱性质以及颗粒形貌的变化。当改变P2O5/Al2O3摩尔比或者缩合温度时,可以看到磷酸根形式H2PO4-,PO34-,H2P3O130-和PO3-的红外光谱特征的变化,P—O键的振动峰随着聚合程度的增加向短波长方向移动,而且峰宽增加。当三聚磷酸二氢铝经高温处理后,拉曼和红外光谱显示了聚合磷酸根中微结构间的相互作用引起P—O键伸缩振动频率增大以及结晶水的变化趋势,随着组成变化的同时,其颗粒的层状结构层厚度增加,层边界趋于模糊,直至呈现熔体状态。

Spectroscopy Characteristics of Various Aluminum Phosphates in A12O3-P2O5-H2O System and Its High Temperature Products

Various aluminum phosphates were prepared with phosphoric acid and aluminum hydroxide under different conditions.IR,XRD,Raman and SEM were used to study the structure difference and their change in heating process and particle morphology of obtained products and aluminum tripolyphosphate.The results show that the spectral characteristic change of phosphate from H2PO-4,PO3-4,H2P3O3-10 and PO-3 can be seen when P/Al molar ratio=3 or the condensation temperature is different.The PO symmetric stretching peaks shift to lower wavenumber and the bands widen along with the extent of polymerization.After aluminum tripolyphosphate is heated,the frequencies of stretching vibrational modes depend on the micro-structure units of phosphate and increase with the extent of polymerization.Both Raman and infrared spectra can characterize the pattern of the hydroxyl stretching vibrations.The laminated thickness of reaction product is increases and laminar boundary is vague until the clinker clew is formed.