摘要: |
参照《水质 化学需氧量的测定 重铬酸盐法》(HJ 828—2017)标准,设计出三水平四因素正交试验方案,考察水样体积、消解温度、消解时间和硫酸银-硫酸溶液加入量对化学需氧量(CODCr)测量值的影响。研究表明:测定CODCr质量浓度>50 mg/L的样品时,影响CODCr测定值的主次因素排序为:水样体积、硫酸银-硫酸溶液加入量、消解时间和消解温度;CODCr测定的最优试验条件为:水样体积5 mL、消解温度200 ℃、消解时间90 min、硫酸银-硫酸溶液加入量10 mL。与《HJ 828—2017》标准中的监测条件相比,该方法分析时间更短、加入的硫酸银-硫酸溶液体积更少,在应急监测中具有更高的参考价值。 |
关键词: 正交试验 化学需氧量 影响因素 最优试验条件 |
DOI: |
分类号:X832 |
基金项目: |
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Analysis of Influencing Factors of CODCr Determination Based on Orthogonal Test Method |
LIN Hai-xiang
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Haimen Ecological Environmental Monitoring Station, Nantong, Jiangsu 226100,China
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Abstract: |
A three-level and four-factor orthogonal test was designed to investigate the effects of water sample volume, digestion temperature, digestion time, and the dosage of silver sulfate-sulfuric acid solution on chemical oxygen demand (CODCr) according to the standard
Water Quality determination of the Chemical Oxygen Demand dirchromate Method(HJ 828—2017). The corresponding results indicated that: when the CODCrconcentration was more than 50 mg/L, the primary and secondary factors affecting the determination value of CODCrwere water volume, silver sulfate-sulfuric acid solution volume, digestion time and digestion temperature. The optimal test conditions for the determination of CODCr were as follows: 5 mL of water sample being digested at 200 ℃ for 90 min with 10 mL of silver sulfate sulfuric acid solution. Compared with the conditions in the standard method (HJ 828—2017), the shorter analysis time and less dosage of silver sulfate-sulfuric acid solution make this method show a higher reference value in emergency monitoring. |
Key words: Orthogonal test CODCr Influencing factors Optimal test conditions |