用折射率法测水中三聚氰胺质量浓度

Determination of Melamine Concentration in Water Based on Refractive Index Method

配制了不同质量浓度的三聚氰胺溶液,对其在不同温度和pH值下的折射率进行了测定.结果发现:在相同温度下,三聚氰胺溶液的折射率随质量浓度的增大而增大;在相同质量浓度下,三聚氰胺溶液的折射率随温度的升高而降低;在酸性条件下,pH值对三聚氰胺溶液折射率有一定的影响;在碱性条件下,pH值对折射率几乎没影响.通过线性拟合得出质量浓度、温度和pH值三者之间的关系式,误差分析表明计算值符合实验值.

Melamine solutions with different mass concentrations were prepared,and their refractive indexes under different pH values and different temperatures were determined.The result shows that the refractive index of melamine solution increases with increasing of the mass concentration at the same temperature,decreases with increasing of the temperature at the same mass concentration.The pH value has a certain impact on refractive index under acidic conditions,but almost has no impact on refractive index under alkaline conditions.Through the linear fitting,the relationship between mass concentrations,temperature,pH values was determined.The error analysis shows that measured values conformed to experimental values.