Abstract:
Conventional methods using o-tolidine and N,N-diethyl-p-phenylenediamine as colorimetric reagents have been extensively applied worldwide in residual chlorine measurement for water quality and environmental management. Different types of interferences resulting in erroneous measurements while using colorimetry have been previously reported. In this study, we experimentally demonstrated micro-particles as interfering substances in selected inorganic (five metal oxidants) and organic (microalgae) particles. The results indicated erroneous measurements (viz. colour development) for three of the selected particles. These erroneous measurement levels were evaluated with reference to the chlorine concentration (in mg-Cl2/L, hereafter represented as mg/L) in relation to both representative colorimetric reagents in terms of the amount of particles and time variations. A novel viewpoint that filtration could be a possible solution to the erroneous measurement caused by such micro-particles was proposed.
摘要:
使用邻甲苯胺和N,N-二乙基对苯二胺作为比色试剂已在世界范围内广泛用于水质和环境管理的余氯测量。先前已经报道了在使用比色法时导致错误测量的不同类型的干扰。在这项研究中,我们通过实验证明了微粒是选定的无机(五种金属氧化剂)和有机(微藻)颗粒中的干扰物质。结果表明测量错误(即颜色显影)为三个选定的颗粒。这些错误的测量水平是参考氯浓度(以mg-Cl2/L为单位,以下表示为mg/L),与两种代表性比色试剂在颗粒量和时间变化方面的关系。提出了一种新颖的观点,即过滤可以解决由此类微粒引起的错误测量。