二安替比林对-(-2,4-二硝基苯氧基-)-苯基甲烷与铬显色反应的研究

Chromogenic Reaction of Cr(Ⅵ) with Diantipyrinyl [p-(-2,4-Dinitrophenoxy-)-]Phenyl Methane

合成新试剂二安替比林对 - (- 2 ,4-二硝基苯氧基 - ) -苯基甲烷 (DAp DNPPM) ,以正交试验设计寻找该试剂与微量 Cr( )显色反应的最佳显色条件。最佳条件为 :最大吸收波长 485 nm,显色剂 1.0 0 % DAp DNPPM用量 0 .6 0 ml,(1+4 ) H3 PO4用量 3.0 0 ml,0 .40 mol.L- 1 Mn( )用量 8.0 0 ml,加热温度 85℃ ,加热时间 8min。在 0 .10～ 0 .80μg/ 2 5 ml范围内呈现良好线性关系 ,线性回归方程为 :A =1.0 36 C (μg/ 2 5 ml) - 0 .0 0 8,r =0 .998。摩尔吸光系数为 1.30× 10 6L .mol- 1 .cm- 1 。用该法测定水样中 Cr ( )含量 ,结果满意。

Diantipyrinyl\[ p ( 2,4 Dinitrophenoxy ) \]phenyl methane (DApDNPPM) is prepared The best conditions of the chromogenic reaction of diantipyrinyl \[ p-( 2,4 dinitrophenoxy ) \]phenyl methane with Cr(Ⅵ) are sorted out by orthogonal design With the addings of 0 60ml 1 00% DApDNPPM,3 00 ml (1+4)H 3PO 4,8 00 ml 0 40 mol/L Mn(Ⅱ) at 85℃ water bathing for 8 min,a good linear relation is available in the Cr(Ⅵ) concentration range from 0 10 to 0 80 μg/25 ml There is a maximum absorbance at 485 nm The linear regression equation is A=1 036C(μg/25 ml)-0 008(r=0 998) The molar absorptivity is 1 30×10\+6 L·mol -1 cm -1 The proposed method is applied to the determination of Cr(Ⅵ) in the sample of water with satisfactory results