钼蓝光度法测定高纯氧化铋中微量硅

DETERMINATION OF TRACE SILICON IN HIGH-PURITY BISMUTH OXIDE BY MOLYBDENUM BLUE PHOTOMETRIC METHOD

采用氢溴酸直接分解高纯氧化铋试样,并使铋生成易挥发的溴化铋除去,从而消除了铋对测定硅的干扰,硅以钼蓝光度法测定。其最大吸收波长为810nm,表观摩尔吸光系数为2 12×104L·mol-1·cm-1,二氧化硅在0～60μg/50mL范围内符合比耳定律。该方法用于高纯氧化铋中微量硅的测定,获得满意结果,适用于高纯氧化铋中0 001%～0 01%SiO2的测定,其RSD为1 50%～6 94%、回收率为96 00%～105 10%。

The molybdenum blue photometric method is used to determine trace silicon in highpurity bismuth trioxideThrough dissolving the bismuth sample in hydrobromic acid,the bismuth bromide is formed and volatilized,so that bismuth disturbance is eliminatedThe maximum absorbance is obtained at a wavelength of 810nm with an apparent molar absorptivity of 212×104L·mol-1·cm-1Beer's law is obeyed when the concentration of SiO2 is within the range of 0～60μg/50mLThe method has been satisfactorily applied in determination of trace silicon in highpurity bismuth oxideFor SiO2 concentration of 0001%～001%,the RSD of 150%～694% and the recovery of 9600%～10510% can be obtained