返滴定法测定白矾散中白矾的含量

摘要

建立了白矾散中白矾含量测定的方法.样品在600℃灰化2 h,稀盐酸溶解,过量EDTA-2Na配位AL3+,以二甲酚橙作为指示剂,锌滴定液滴定剩余的EDTA-2Na,计算白矾的含量.经方法学考察,本方法符合含量测定要求,平均回收率为97.6%,RSD为0.8%.所建立的测定方法结果稳定可靠、重现性好,可用于白矾散的质量控制.%To establish a quantitative method for alumen in baifan power,the sample was dissolved by dilute HCl after it was ashed in 600℃ for 2 h. AL3+and EDTA-2Na formed a complex. Using xylene orange as an indicator, excess amount EDTA-2Na was titrated by zinc titration solution. The content of alumen can be calculated. Through the study methodology, approach was consistent with determination requirements. The average recovery rate was 97.6%(RSD=0.8%). The method was reliable and stable with a good reproducibility, which can be applied in quality control of baifan power.