PH1834 | 0.5%铬黑T指示剂 Eriochrome Black T Indicator (0.5%)

CAS号: 1787-61-7
英文名称: Eriochrome Black T
英文同义词: EBT;NBC2;NBC3;SBC2;F-241;NBC2B;ERIO T;SLC4A6;SLC4A7;CI 14645
中文名称: 铬黑 T
中文同义词: BT;铬黑T;媒染黑T;媒介黑T;铬黑 T;酸性铬黑T;依来铬黑T;沙洛克罗黑;媒介黑11;羊毛铬黑T
CBNumber: CB5457454
分子式: C20H12N3NaO7S
分子量: 461.38
铬黑 T化学性质
密度 : 1.109 g/mL at 25 °C
闪点 : 185 °C
储存条件 : Store at RT.
溶解度 : 50g/l
形态: Powder/Solid
色指数 : 14645
颜色: Brownish-black to black
PH值: 3.7 (10g/l, H2O, 20℃)
水溶解性 : 50 g/L (20 ºC)


化学性质 

黑褐色粉状。溶于水，并呈枣红至桨红色；稍溶于醇，并呈棕光品红色；微溶于丙酮。在浓硫酸中呈暗蓝色，稀释后呈浅红棕色；在浓硝酸中呈枯桔黄色。其水溶液，加浓盐酸无大变化；加氢氧化钠浓溶液转棕光品红色。水中溶解度（90℃）为25g/L。染色时遇铜、铁，色光影响较大。


用途 

主要用于羊毛纺织物的染色和印花，也可用于蚕丝、锦纶等纺织物的梁色，还可用于毛皮染色。纯品可作指示剂用。

测定水硬度用指示剂，金属络合指示剂，测定钙、镁、钡、姻、锰、铅、钪、锶、锌和锆。

常温运输与保存，12个月有效

Eriochrome Black T is a complexometric indicator that is used in complexometric titrations, e.g. in the water hardness determination process. It is an azo dye. 


In its protonated form, Eriochrome Black T is blue. It turns red when it forms a complex with calcium, magnesium, or other metal ions.


Applications
When used as an indicator in an EDTA titration, the characteristic blue end-point is reached when sufficient EDTA is added and the metal ions bound to the indicator are chelated by EDTA, leaving the free indicator molecule.


Eriochrome Black T has also been used to detect the presence of rare earth metals.


References
^ http://www.sigmaaldrich.com/catalog/product/sial/858390?lang=en&region=US
^ Dubenskaya, L. O.; Levitskaya, G. D. (1999). "Use of eriochrome black T for the polarographic determination of rare-earth metals". Journal of Analytical Chemistry. 54 (7): 655–657. ISSN 1061-9348.