酸碱滴定法测定硼粉中硼  

Determination of boron content in boron powder by acid-base titration method

作　　者：赵志刚[1] 韦雪梅[1] 赵华丽[1] 聂海英[1] ZHAO Zhigang;WEI Xuemei;ZHAO Huali;NIE Haiying(Hubei Institute of Aerospace Chemical Technology,Xiangyang 441003,China)

机构地区：[1]湖北航天化学技术研究所,湖北襄阳441003

出　　处：《化学分析计量》2023年第12期37-42,共6页Chemical Analysis And Meterage

摘　　要：以酸碱滴定法测定硼粉中硼含量。称样质量为0.14~0.20 g,加酸加热回流50 min,定容至500 mL,移取50.00 mL作为样品溶液。样品溶液先用碱液中和至pH 5.4,然后加入5 g甘露醇,用0.1 mol/L氢氧化钠标准滴定溶液滴定,临近终点时记录消耗的体积与试液pH值,用二级微商法算得终点体积。硼含量测定结果的相对标准偏差为0.32%~0.42%(n=9)。对比测定硼酸硼含量,该方法所得结果的相对标准偏差为0.05%(n=5)。Boron content in boron powder was determined by acid-base titration method.The sample weight of boron powder was 0.17-0.20 g,heation reflux for 50 min,dilute to 500 mL with water,and 50.00 mL of which was selected as the sample solutiion.The sample solution was first neutralized with alkaline solution to pH 5.4,and then 5 g mannitol was added.The sample solution was titrated with 0.1 mol/L sodium hydroxide standard titration solution,the volume of titration solution and pH value was recorded near the endpoint,the endpoint volume was calcuated by using the second derivative method.The relative standard deviation of detection results of boron content was 0.32%-0.42%(n=9).Compared with the determination of boron borate content,the relative standard deviation of the results obtained by this method was 0.05%(n=5).

关 键 词：无定形硼粉 PH值 二级微商法 硼含量 

分 类 号：O657[理学—分析化学]