Reaction endpoint judgment device and five-step iodometry

A technology of reaction end point and judging device, which is applied in the direction of analysis by chemical reaction of materials, chemical analysis by titration method, material analysis by observing the influence on chemical indicators, etc., can solve the judgment error and influence of titration end point. To solve problems such as changes in the color of the titration end point, to achieve the effect of convenient operation, avoiding subjective limitations, and improving sensitivity and reliability

Active Publication Date: 2016-05-25
SHENZHEN SINSCHE TECH
View PDF7 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The second step of the five-step iodometric method is to continue adding hydrochloric acid to the solution on the basis of the first step to make the pH ≤ 2. At this time, the chlorite converted from the reaction of chlorine dioxide in the first step and the chlorous acid contained in the sample itself Salt participates in the reaction to produce a large amount of iodine. The solution in the second step already contains starch indicator. At this time, because the solution contains a large amount of iodine, the starch will form a colloid to c

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Reaction endpoint judgment device and five-step iodometry
  • Reaction endpoint judgment device and five-step iodometry
  • Reaction endpoint judgment device and five-step iodometry

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0031] This embodiment provides a reaction terminal judging device, which includes a reaction vessel 1, a burette 2 arranged above the reaction vessel 1, the burette 2 is connected to the burette holder 6 through a burette clamp, and a burette arranged on the reaction vessel 1. A monochromatic light source 3 on one side of the outside and a photoelectric receiver 4 located on the other side of the reaction vessel 1 opposite the side of the single-sided light source 3, the photoelectric receiver 4 is connected to a data processing system 5; wherein the reaction vessel 1 is transparent container, the monochromatic light emitted by the monochromatic light source 4 passes through the solution in the reaction container 1 and is received by the photoelectric receiver 4; the data processing system 5 performs data processing on the electrical signal received by the photoelectric receiver Analyze and calculate to obtain the absorbance of the solution. The light wavelength emitted by the...

Embodiment 2

[0034] Present embodiment provides a kind of five-step iodometric method, comprises the steps:

[0035] 1) Mix 3ml of the sample to be tested with 200ml of water and adjust the pH to 7 with phosphate buffer solution, add 10ml of potassium iodide solution with a concentration of 100g / L, and titrate with a standard solution of sodium thiosulfate with a concentration of 0.05mol / L , until the mixed solution becomes pale yellow, adopt the reaction terminal judging device, continue to titrate the sodium thiosulfate standard solution in the mixed solution, and continue to titrate excessively after the solution absorbance value reaches the mutation point, such as figure 2 As shown, draw two straight lines using the least squares method or table tool before and after the mutation point, and calculate the intersection point value of the two straight lines, which is the added volume of sodium thiosulfate at the end of the titration, and record this volume as the added thiosulfate The vo...

Embodiment 3

[0066] Present embodiment provides a kind of five-step iodometric method, comprises the steps:

[0067] 1) Mix 5ml of the sample to be tested with 300ml of water and adjust the pH to 7 with a phosphate buffer solution, add 20ml of potassium iodide solution with a concentration of 100g / L, and titrate with a standard solution of sodium thiosulfate with a concentration of 0.1mol / L , until the mixed solution becomes pale yellow, adopt the reaction end point judging device, continue to titrate the sodium thiosulfate standard solution in the mixed solution, and continue to titrate excessively after the solution absorbance value reaches the mutation point, and calculate the thiosulfate added when the titration end point Sodium sulfate standard solution volume V1, the sodium thiosulfate standard solution volume that adds is V1, V1 is 1.20ml among the present embodiment;

[0068] 2) Gradually add 2ml of hydrochloric acid solution with a concentration of 2.5N to the solution obtained in...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
Light wavelengthaaaaaaaaaa
Login to view more

Abstract

The invention discloses a reaction endpoint judgment device. The device comprises a reaction container, a burette arranged above the reaction container, a monochromatic light source arranged on one side of the outside of the reaction container and a photoelectric receiver located on the other side of the reaction container and opposite to the monochromatic light source, wherein the photoelectric receiver is connected with a data processing system. The invention further discloses five-step iodometry without the step of starch adding. The device and the method effectively solve the problems that color change of a reaction endpoint is influenced and errors are caused to judgment of the titration endpoint due to the fact that a starch indictor is likely to have a reaction with high-concentration iodine in advance in step 2 and step 4 in traditional five-step iodometry and starch forms colloid and wraps the iodine, the device is simple in structure, the method is simple and convenient to operate, and the sensitivity and the accuracy are high.

Description

technical field [0001] The invention belongs to the technical field of disinfectant detection, and in particular relates to a reaction terminal judging device and a five-step iodometric method without adding starch. Background technique [0002] Appendix A of the national standard GB28931-2012 provides a method for detecting the content of chlorine dioxide, chlorine gas, chlorite ions, and chlorate ions produced by chlorine dioxide disinfectant generators, called the five-step iodometric method. The detection principle is to use ClO under different pH conditions 2 , Cl 2 , ClO 2 - , ClO 3 - respectively with I - The reaction produces elemental iodine, and the resulting iodine is titrated with sodium thiosulfate. The detection process is divided into five steps, so it is called the five-step iodometric method. The amount of sodium thiosulfate consumed in each step is used to calculate the amount of each substance. content. [0003] Each step of the traditional five-st...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): G01N31/16G01N21/78
CPCG01N21/78G01N31/16
Inventor 阮建明
Owner SHENZHEN SINSCHE TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap