阅读说明：本技术 一种检测废水中铅离子含量的试纸及其应用 (Test paper for detecting content of lead ions in wastewater and application thereof ) 是由 朱双 高文皓 肖光莉 戚明辉 韩�熙 于 2019-12-17 设计创作，主要内容包括：本发明公开了一种检测废水中铅离子含量的试纸,包括显色试纸片,所述显色试纸片是通过先将滤纸浸泡于显色剂溶液中后取出烘干制得,所述显色剂溶液包括质量浓度为0.04～0.10g/L的4-(2-吡啶偶氮)-间苯二酚溶液。本发明通过采用4-(2-吡啶偶氮)-间苯二酚作为显色剂,与废水中的铅离子反应成为红色或红褐色的化合物,可通过颜色变化明显检测出废水是否含有铅离子,再通过测量显色带长度与标尺对比,读出铅离子含量,克服传统操作人员肉眼观察颜色,测量出的铅离子含量准确度更高。(The invention discloses test paper for detecting the content of lead ions in wastewater, which comprises a color development test paper sheet, wherein the color development test paper sheet is prepared by soaking filter paper in a color development reagent solution, taking out and drying the filter paper, and the color development reagent solution comprises a 4- (2-pyridylazo) -resorcinol solution with the mass concentration of 0.04-0.10 g/L. According to the invention, 4- (2-pyridylazo) -resorcinol is used as a color developing agent and reacts with lead ions in wastewater to form a red or reddish brown compound, whether the wastewater contains the lead ions can be obviously detected through color change, and the content of the lead ions is read by measuring the length of a color developing band and comparing the length with a scale, so that the problem that the traditional operator observes the color by naked eyes is overcome, and the measured content of the lead ions is higher in accuracy.)

1. The utility model provides a test paper of lead ion content in detection waste water, includes the color development test paper piece, the color development test paper piece is taken out the stoving after soaking filter paper in developer solution earlier and is made its characterized in that: the color developing agent solution comprises a 4- (2-pyridylazo) -resorcinol solution with the mass concentration of 0.04-0.10 g/L.

2. The test paper for detecting the content of lead ions in wastewater according to claim 1, which is characterized in that: the developer solution comprises a 4- (2-pyridylazo) -resorcinol solution with the mass concentration of 0.07 g/L.

3. The test paper for detecting the content of lead ions in wastewater according to claim 1 or 2, characterized in that: an ethanol solution is also added into the color developing agent solution.

4. The test paper for detecting the content of lead ions in wastewater according to claim 1, which is characterized in that: the filter paper is rapid quantitative filter paper with the thickness of 70-100 mm multiplied by 2-5 mm.

5. The test paper for detecting the content of lead ions in wastewater according to claim 1, which is characterized in that: the soaking is to soak the filter paper in the color developing agent solution for 5-40 min.

6. The test paper for detecting the content of lead ions in wastewater according to claim 1, which is characterized in that: and the drying refers to drying the soaked filter paper at the temperature of 50-70 ℃ for 7-20 min.

7. A method for rapidly detecting the content of lead in wastewater is characterized by comprising the following steps: firstly, adjusting the pH value of the wastewater to be detected to be 4-8, then inserting the color development test paper sheet of any claim 1-6 into the wastewater to be detected, reacting for 20-30 min, and then comparing with a scale to read the concentration of lead ions.

8. The method for rapidly detecting the content of lead in wastewater according to claim 7, which is characterized in that: and a metal masking agent is added into the wastewater to be detected after the pH value of the wastewater is adjusted.

9. The method for rapidly detecting the content of lead in wastewater according to claim 7, which is characterized in that: the scale test paper is prepared by inserting a plurality of pieces of the chromogenic test paper described in any one of claims 1 to 6 into lead nitrate solutions having concentrations of 1mg/L, 2mg/L, 5mg/L, 10mg/L, 20mg/L, 30mg/L, 50mg/L, 70mg/L, 80mg/L and 100mg/L, respectively, and measuring the heights of reaction zones, measuring the heights of a plurality of sets of reaction zones with the lead nitrate solution having the same concentration, calculating the average value, and labeling the heights and concentrations of the corresponding reaction zones on the chromogenic test paper.

Technical Field

The invention relates to the field of lead ion content detection, in particular to test paper for detecting the lead ion content in wastewater and application thereof.

Background

With the development of industry, the lead pollution in the environment is increased due to the discharge of industrial wastewater, the lead in the environment slowly invades into food, water and various living necessities through various channels, and the living environment is greatly challenged. Lead and its compounds have certain toxicity, and can be harmful to nervous system, hemopoietic system, digestive system, kidney system, cardiovascular system, endocrine system, etc. At present, most of common lead poisoning belongs to mild chronic lead poisoning, and the main pathological changes are that lead influences metal ions and enzyme systems in vivo to cause vegetative nerve functional disturbance, anemia, low immunity and the like. In order to protect the health of people, lead detection on various foods, water sources and living necessities which are contacted in life is particularly important. The method for measuring the lead content can be used for detecting the lead content by methods such as an atomic fluorescence method, a spectrophotometry method and the like, but can be carried out only by matching with large-scale instruments, and cannot meet the requirement of on-site rapid detection due to complex detection operation, high cost and long period.

Therefore, the test paper for detecting the lead content is produced, the defect of detection by a large-scale instrument is overcome, most test paper can only detect whether the test paper contains lead, and the lead content in the test paper cannot be measured, the Chinese patent invention No. 2015100351873 discloses a quick test paper for detecting the lead content with an extended validity period and a preparation method thereof, the test paper compares the color of a color development color block of the test paper with a prepared colorimetric card when detecting the lead content, the content of lead ions is read out semi-quantitatively, the lead content of the test paper is related to the subjective judgment color of an operator when in measurement, and the test paper has larger error.

Disclosure of Invention

The invention aims to provide the test paper for detecting the content of lead ions in wastewater, which can be used for measuring the concentration of the content of lead by developing the length of a color zone and overcomes the defects of the traditional test paper measurement.

In order to achieve the purpose, the invention adopts the following technical scheme:

the test paper for detecting the content of lead ions in wastewater comprises a color development test paper sheet, wherein the color development test paper sheet is prepared by soaking filter paper in a color development agent solution, taking out and drying the filter paper, and the color development agent solution comprises a 4- (2-pyridylazo) -resorcinol solution with the mass concentration of 0.04-0.10 g/L.

Further, the developer solution comprises 4- (2-pyridylazo) -resorcinol solution with the mass concentration of 0.07 g/L.

Further, an ethanol solution is added into the color developing agent solution.

Furthermore, the filter paper is rapid quantitative filter paper with the size of 70-100 mm multiplied by 2-5 mm.

Further, the soaking refers to soaking the filter paper in the color developing agent solution for 5-40 min.

Further, the drying refers to drying the soaked filter paper at the temperature of 50-70 ℃ for 7-20 min.

The invention also provides a method for rapidly detecting the content of lead in the wastewater, which comprises the following steps: firstly, adjusting the pH value of the wastewater to be detected to be 4-8, then inserting the color development test paper sheet into the wastewater to be detected to react for 20-30 min, and then comparing the color development test paper sheet with a scale to read the concentration of lead ions.

Further, a metal masking agent is added into the wastewater to be detected after the pH value of the wastewater is adjusted.

Further, in the scale test paper, a plurality of pieces of the color development test paper described in any one of claims 1 to 6 are inserted into lead nitrate solutions having concentrations of 1mg/L, 2mg/L, 5mg/L, 10mg/L, 20mg/L, 30mg/L, 50mg/L, 70mg/L, 80mg/L and 100mg/L, respectively, and the heights of the reaction bands are measured, and a plurality of sets of the heights of the reaction bands are measured with the lead nitrate solution having the same concentration, and an average value is determined, and the corresponding heights and concentrations of the reaction bands are marked on the color development test paper.

The invention has the following beneficial effects:

(1) 4- (2-pyridylazo) -resorcinol is adopted as a color developing agent and reacts with lead ions in the wastewater to form a red or reddish brown compound, whether the wastewater contains the lead ions can be obviously detected through color change, and the content of the lead ions is read by measuring the length of a color developing band and comparing the length with a scale, so that the problem that the traditional operator observes the color by naked eyes is solved, and the measured content of the lead ions is higher in accuracy;

(2) by adding the ethanol solution into the color developing agent solution, the reaction of 4- (2-pyridylazo) -resorcinol and lead ions can be accelerated, and the detection of plastics is improved;

(3) adjusting the pH value before measuring the wastewater to reach 4-8, wherein the optimal value is 5.5, and the developing length and developing boundary of the developing test paper sheet are good;

(4) by adding metal masking agents to the wastewater, other metal ions (e.g., Ni) in the wastewater can be reduced²⁺，Zn²⁺，Cu²⁺，Fe³⁺，Fe²⁺，Cr(VI)，Mg²⁺Etc.) on the developed test paper sheet.

Drawings

Fig. 1 is a schematic structural diagram of a ruler according to the present invention.

FIG. 2 is a standard curve of instrumental analysis of 1-20mg/L lead ion solutions measured by the method.

FIG. 3 is a standard curve of instrumental analysis of 20-100mg/L lead ion solutions measured by the method.

Detailed Description