【摘要】 建立了极谱测定邻甲基苯甲酸中邻苯二甲酸含量的方法。在 6.4× 1 0 -2 mol/L H3 PO4-KH2 PO4( p H 1 .82 )缓冲溶液中 ,邻苯二甲酸极谱催化氢波的峰电位 EP为 - 1 .32 V ( vs. SCE) ,其二阶导数峰峰电流 i″p 与邻苯二甲酸浓度在 5 .0× 1 0 -7～ 4.0× 1 0 -5mol/L和 4.0× 1 0 -5～ 2 .0× 1 0 -3mol/L范围内呈线性关系。1 0次测量 1 .0× 1 0 -5mol/L邻苯二甲酸还原波二阶导数峰峰电流 ,相对标准偏差 RSD为 1 .7% ,5 0 0 ( w/w)倍邻甲基苯甲酸不干扰测定邻苯二甲酸时。更多还原

【Abstract】 A polarographic method for the determination of phthalic acid in toluic acid is proposed based on its catalytic hydrogen wave with peak potential-1.32V(vs/SCE)in 6.4×10 -2 mol/L H 3PO 4 KH 2PO 4(pH1.82)buffer.The 2nd order derivative peak current of the wave is rectilinear to phthalic acid concentration in the rang of 5.0×10 -7 ～4.0×10 -5 mol/L and 4.0×10 -5 ～2.0×10 -3 mol/L.The relative standard deviation(RSD)is 1.7% for 10 independent measurements of 1.0×10 -5 mol/L phthalic acid.500 times(W/W) toluic acid does not interfere with the determination.The proposed method is estimated by determination of phthalic acid and by recovery test in four suggested sythensed samples with different impurity level.更多还原