化学分析计量
化學分析計量
화학분석계량
CHEMICAL ANALYSIS AND METERAGE
2014年
2期
50-53
,共4页
余氯%3,3’,5,5’-四甲基联苯胺%目视比色法
餘氯%3,3’,5,5’-四甲基聯苯胺%目視比色法
여록%3,3’,5,5’-사갑기련분알%목시비색법
residual chloride%TMB%visual colorimetry
为解决GB/T 5750.11-2006生活饮用水标准检验方法中的3,3’,5,5’-四甲基联苯胺(TMB)目视比色法检测余氯时出现的评价方法准确性欠佳、TMB显色剂发黄、显色体系偏绿等问题,对TMB目视比色法的评价方法、TMB显色剂的配制条件和水样的检测条件进行了研究。结果表明,次氯酸钠不宜作为余氯标准物质来评价TMB目视比色法的改进效果,而通过检测显色体系的A450和目视比色值相结合的方法来判断方法改进效果更为准确。采用优级纯浓盐酸和无氯纯水室温搅拌溶解,可使显色剂无色透明,从而解决TMB显色剂发黄的问题,符合国标要求。将显色剂配制用酸(盐酸)的浓度由国标中0.1 mol/L变更为0.6 mol/L,可解决余氯显色体系偏绿的问题。显色体系pH变化后,显色时间、显色温度、显色剂用量可仍按照国标方法的要求进行操作。通过以上改进措施,进一步提高了余氯检测结果的准确度。
為解決GB/T 5750.11-2006生活飲用水標準檢驗方法中的3,3’,5,5’-四甲基聯苯胺(TMB)目視比色法檢測餘氯時齣現的評價方法準確性欠佳、TMB顯色劑髮黃、顯色體繫偏綠等問題,對TMB目視比色法的評價方法、TMB顯色劑的配製條件和水樣的檢測條件進行瞭研究。結果錶明,次氯痠鈉不宜作為餘氯標準物質來評價TMB目視比色法的改進效果,而通過檢測顯色體繫的A450和目視比色值相結閤的方法來判斷方法改進效果更為準確。採用優級純濃鹽痠和無氯純水室溫攪拌溶解,可使顯色劑無色透明,從而解決TMB顯色劑髮黃的問題,符閤國標要求。將顯色劑配製用痠(鹽痠)的濃度由國標中0.1 mol/L變更為0.6 mol/L,可解決餘氯顯色體繫偏綠的問題。顯色體繫pH變化後,顯色時間、顯色溫度、顯色劑用量可仍按照國標方法的要求進行操作。通過以上改進措施,進一步提高瞭餘氯檢測結果的準確度。
위해결GB/T 5750.11-2006생활음용수표준검험방법중적3,3’,5,5’-사갑기련분알(TMB)목시비색법검측여록시출현적평개방법준학성흠가、TMB현색제발황、현색체계편록등문제,대TMB목시비색법적평개방법、TMB현색제적배제조건화수양적검측조건진행료연구。결과표명,차록산납불의작위여록표준물질래평개TMB목시비색법적개진효과,이통과검측현색체계적A450화목시비색치상결합적방법래판단방법개진효과경위준학。채용우급순농염산화무록순수실온교반용해,가사현색제무색투명,종이해결TMB현색제발황적문제,부합국표요구。장현색제배제용산(염산)적농도유국표중0.1 mol/L변경위0.6 mol/L,가해결여록현색체계편록적문제。현색체계pH변화후,현색시간、현색온도、현색제용량가잉안조국표방법적요구진행조작。통과이상개진조시,진일보제고료여록검측결과적준학도。
In order to solve problems of TMB visual colorimetry, such as poor accuracy of evaluation method of improved testing method, yellow color of TMB solution and partial green color of color system in GB/T 5750.11-2006 in determination of residual chloride in water,improved evaluation method, preparation conditions of TMB chromogenic agent and testing conditions of residual chlorine water were researched. Results showed that sodium hypochlorite should not be used as standard substance to evaluate the improving effect of TMB visual colorimetry, evaluating by A450 and visual colorimetric value of chromogenic system was more accurate. Preparing TMB chromogenic agent with hydrochloric acid(GR)and pure water without residual chlorine at room temperature could make chromogenic agent colorless and transparent, solve the problem of yellow color of TMB solution, conform to requirements of GB/T 5750.11-2006. It could solve the problem of partial green color of color system by changing the concentration of hydrochloric acid, which was used to prepare TMB solution, from 0.1 mol/L to 0.6 mol/L, while chromogenic time, color temperature and dosage of chromogenic agent still could be operated according to requirements of national standard. Accuracy of testing results of residual chlorine was further improved through above measures.