Method for determination of the content of main components of phosphorus trichloride hydrolysis solution

A technology of phosphorus trichloride and determination method, which is applied in the direction of chemical analysis by titration method, can solve the problems such as inability to obtain content data, inability to measure phosphoric acid content, inability to accurately determine the content of hydrochloric acid, etc., and achieves good reproducibility, High accuracy and easy operation

Inactive Publication Date: 2013-10-23
CHONGQING UNISPLENDOUR CHEM
View PDF7 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, when phosphoric acid also exists in the solution, only the double indicator method is used for acid-base titration, neither the content of hydrochloric acid nor the content of phosphorous acid can be accurately measured, let alone the content of phosphoric acid.
In the chemical industry standard "HG

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
  • Method for determination of the content of main components of phosphorus trichloride hydrolysis solution
  • Method for determination of the content of main components of phosphorus trichloride hydrolysis solution
  • Method for determination of the content of main components of phosphorus trichloride hydrolysis solution

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0037] Accurately weigh 1.2085 g of phosphorus trichloride hydrolyzate sample with a weighing bottle, add it into a 250 mL beaker filled with 150 mL of water, place it on a magnetic stirrer, insert a precision pH meter electrode, start stirring, and use a concentration of 0.5042 mol / L of sodium hydroxide standard titration solution is dripped to solution pH=4.5, and the volume V of the consumed sodium hydroxide standard titration solution is recorded 1 It is 20.23mL; continue to titrate with sodium hydroxide standard titration solution with a concentration of 0.5042mol / L until pH=9.5, and record the volume V of the standard titration solution consumed 2 It is 5.71mL; then add 10mL of neutral calcium chloride solution with a concentration of 100g / L adjusted to reddish with 0.05mol / L sodium hydroxide solution before using phenolphthalein as indicator, and use a 10mL alkaline burette Fill 0.05mol / L sodium hydroxide standard titration solution, drop to pH=7.53, write down the vol...

Embodiment 2

[0059] Embodiment 2 (standard addition recovery test)

[0060] In order to further verify the accuracy of the results, a standard recovery test was also carried out in this example:

[0061] 1) Take an appropriate amount of analytically pure hydrochloric acid, phosphoric acid, and phosphorous acid, and prepare them into hydrochloric acid solution, 20% phosphorous acid solution, and 0.5% phosphoric acid solution with a mass fraction of 20%, respectively, and measure their concentrations according to the methods stipulated in the national standard. exact content. The content of hydrochloric acid (HCl) in hydrochloric acid solution was 20.12%, the content of phosphorous acid in phosphorous acid solution was 19.88%, and the content of phosphoric acid in phosphoric acid solution was 0.56%.

[0062] 2) Use the phosphorous trichloride hydrolyzate with known contents of hydrochloric acid, phosphorous acid and phosphoric acid in the above Example 1 as the sample in a weighing bottle, ...

Embodiment 3

[0074] In order to further accurately determine the main components of the phosphorus trichloride hydrolyzate, the present embodiment also takes the phosphoric acid solution of known concentration as a sample, and measures according to the method of the present invention. When adjusting its pH value to 9.5, add neutral chloride Calcium solution, titrate with 0.05mol / L sodium hydroxide standard titration solution, record the change of pH value with the volume of titrant during the titration process, and determine the pH value of the stoichiometric point at which disodium hydrogen phosphate is completely titrated.

[0075] Accurately take by weighing content to be the analysis pure phosphoric acid 0.0585g of 85.0%, after adding neutral calcium chloride solution in the step in embodiment 1, titrate with the sodium hydroxide standard titration solution of 0.05255mol / L, record pH in the titration process The value varies with the volume of the titrant. Take the consumed volume of t...

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

No PUM Login to view more

Abstract

The invention relates to a method for determination of the content of main components of a phosphorus trichloride hydrolysis solution. The method is carried out according to the following steps: 1) accurately weighing a phosphorus trichloride hydrolysis solution sample, adding water, in the condition of stirring, titrating the solution to the pH of 4.5 with a sodium hydroxide standard titration solution, and recording consumption volume V1 of the sodium hydroxide standard titration solution; 2) continuing to titrate the solution to the pH of 9.5 with the sodium hydroxide standard titration solution, and recording consumption volume V2 of the sodium hydroxide standard titration solution; 3) further adding an excess neutral calcium chloride solution, titrating the solution to the pH of 7.53 with the sodium hydroxide standard titration solution, and recording consumption volume V3 of the sodium hydroxide standard titration solution; and 4) calculating results. Through use of the method, fast and real-time detection of the content of hydrochloric acid, phosphorous acid and phosphoric acid in the phosphorus trichloride hydrolysis solution can be realized, and the method has the advantages of simple operation, high accuracy, good precision, good reproducibility and the like. But if a conventional acid-base indicator method is adopted, the phosphorus trichloride hydrolysis solution sample cannot be accurately determined because of low phosphoric acid content in the phosphorus trichloride hydrolysis solution sample.

Description

technical field [0001] The invention relates to the detection of phosphorus trichloride hydrolyzate, in particular to a method for measuring the main component content of phosphorus trichloride hydrolyzate. Background technique [0002] Phosphorus trichloride is a colorless liquid and is a common raw material for the production of organophosphorus compounds. It is widely used in the production of pesticides, medicines, dyes, phosphorus plasticizers and combustion aids. It has a melting point of -111.8°C and a boiling point of 75.2°C. It is soluble in organic solvents such as carbon disulfide, ether, and benzene. When it encounters water, it decomposes violently and reacts with water to form phosphorous acid and hydrochloric acid. Phosphorous acid can be slowly oxidized to phosphoric acid. Therefore, phosphorus trichloride hydrolyzate contains phosphorous acid, hydrochloric acid and a small amount of phosphoric acid. Phosphorous acid is often used as a raw material for the p...

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): G01N31/16
Inventor 罗延谷何咏梅胡欣李文艳朱丽利丁永良
Owner CHONGQING UNISPLENDOUR CHEM
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