GB/T 13070-1991 铀矿石中铀的测定 电位滴定法

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中华人民共和国国家标准

Gs/T13070一91

铀矿石中铀的测定电位滴定法

Determinationofuraniumcontentinuraniumores

bymethodofpotentiometrictitration

1991一07一15发布1992一06一01实施

国iiR技术监督局发布

目次

主题内容与适用范围介·····”·“·····””··············，·，·········.，··················，····…·…(

引用标准········“·”·….，·········..··············”····“···”·········”············“·········一(

第一篇亚铁一钒酸按电位滴定法测定

方法提要······················”·”········”·············“·”·”····································、·…(1

J

勺试剂···，··················“········‘·”····”··“··········‘·······”········”···，··················，……(1

﹄

﹄

U仪器设备·(2

召

U试样···········“·····“········“·”··..·”···········.··”···“······”·····“·“············”·”·····一·(2

~

了测定步骤”·······一(3

n

已结果计算·············”···“···”······”·”··········”····“········“························……(3

0

户方法精密度···“，··“·”····“···”···.，····”··，······”··，·“·”······“··”···”·····“·······……(4

第二篇亚社一钒酸按电位滴定法测定

IQ方法提要···”··‘，·，··..·“·····”····一·(4)

II试剂···········，··················..·”·.’····”“············“···”··············”········”·……(4)

12仪器设备············“···“，··“·“·············，··············”····”···········“··“··········……(5)

13试样一·(5)

14测定步骤········“·”·······”·····“·················“··········“············”·····”“···”····……(5)

15结果计算·····”······“····”·····‘·················”········”·····，·”··”···”，···”····”·····‘·…(6)

16方法精密度·····.，·“·“····“··················“·········“····“····“···········“·······”·……(6)

中华人民共和国国家标准

铀矿石中铀的测定电位滴定法GB/T13070-91

Determinationofuraniumcontentinuraniumores

勿methodofpotentiometrictitration

1主肠内容与适用范围

本标准规定了铀矿石中铀的测定:亚铁一钒酸按电位滴定法及亚钦一钒酸按电位滴定法.

本标准适用于花岗岩、花岗岩类型铀矿石中铀含量的仲裁分析、标准物质定值及验证其他分析方

法，也适用于金属铀、氧化铀等纯铀物质的定值和检验。在带色体系、光线强或弱的环境中照常使用，测

定范围0.01Ye-n%。小于或等于10mg钥(VI),4.2mg钒(V),3mg饰(N),5mg钻(N)不干扰测定;

亚钦一钒酸按电位滴定法测定范围。.01纬~，%。小于或等于25mg钥(19),0.1mg钒(V),1.5mg钵

(IV),4mg桔(N)不干扰测定，一般铀矿石中杂质量均小于上述干扰限量，不经分离就可测定。

本标准有亚铁、亚钦两个标准方法供选择使用。

2引用标准

GB6379计量方法的精密度通过实验室间试验确定标准测试方法的重复性和再现性。

第一篇

亚铁一钒酸按电位滴定法测定

3方法提要

试样经盐酸、氢氟酸和磷酸分解，溶液中的铀(l7)在微沸的磷酸((1+2)介质中，用硫酸亚铁按还原

成铀(N)。用亚硝酸钠氧化过量的亚铁，稳定的铀(N)不被氧化，用尿素消除过剩的亚硝酸钠。用钒酸

按作滴定剂，电位滴定法求测终点。其离子反应式为:

U'++2VOi-}-4H+=UO毛++2VO'++2Hr0

滴定过程可以认为是两个半反应在容器里形成了一个电池，该体系的电位随滴定剂的增加而发生变化。

到等当点时，生成物和反应物的离子浓度相等，其电位计算式是:

E=1/3(2Euo'+N'++Ev0o-rvo'+)+0.1571ogCH+)

通过已知浓度的钒酸按用量和电位计上测出的相应电位值，便可算出待测铀(N)的量。

试荆(除注明外均为分析纯，配制溶液用水系蒸馏水或去离子水)

4.1磷酸(优级纯),85%(，/二)。

42.盐酸(优级纯),36%一38(二/二).

43氢氟酸,40%(。/，)。

国家技术监督局1991一07一15批准1992一06一01实施

GB/T13070一91

4.4过氧化氢,30%(，/。)。

4.5磷酸，85%(二/二)。

4.6磷酸(1+2)e

4.