Quantitative analysis method for isocyanato in melamine tail gas

A technology of melamine and isocyanate, applied in the direction of chemical analysis by titration method, can solve problems such as no effective solution

Pending Publication Date: 2021-09-07
SHANXI YANGMEI FENGXI FERTILIZER IND GRPCO
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0002] There is a large amount of ammonia in the melamine tail gas. During the titration of isocyanic acid and its esters, ammonia reacts with hydrochloric acid to form ammonium chloride. Therefore, when titrating isocyanic acid and its lipids, ammonia and its esters must be removed in advance Salt substances, but in the current prior art, there is no effective solution to solve the above technical problems

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
  • Quantitative analysis method for isocyanato in melamine tail gas

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0023] The following clearly and completely describes the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, but not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

[0024] The invention provides a method for quantitative analysis of isocyanate in melamine tail gas, comprising the following steps:

[0025] S1, sampling, using aluminum foil sampling bag to collect melamine tail gas, aluminum foil sampling bag is equipped with distilled water;

[0026] S2, transfer liquid, move the solution in the aluminum foil sampling bag into the 500ml volumetric flask;

[0027] S3. Accurately pipette 50.0ml of the sample to be tested into the iodine measuring bottle, add 20ml of analytically pure formaldehyde...

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 melamine tail gas analysis, in particular to a quantitative analysis method for isocyanato in melamine tail gas. The quantitative analysis method comprises the following steps of: S1, carrying out sampling; S2, carrying out pipetting; S3, accurately transferring 50.0 ml of a to-be-detected sample into an iodine flask, adding 20 ml of an analytically pure formaldehyde solution, dropwise adding a plurality of drops of a phenolphthalein indicator, and neutralizing with a 1.0 mol / L NaOH standard solution until the solution is light red; S4, heating the iodine flask on an electric furnace until boiling for 1 minute; S5, plugging, cooling to room temperature, not forming negative pressure in the flask, adding 5mL of a di-n-butylamine toluene solution into the iodine flask by using a transfer pipette, and leaching the wall of the iodine flask by using 10ml of toluene; S6, adding 50 ml of acetone into a measuring cylinder, and subjecting the mixture to a standing reaction for 15 min at the room temperature; S7, titrating excessive di-n-butylamine by using a potentiometric titration method or a chromogenic titration method; and S8, calculating the content of isocyanato according to a titration result in S7. The new quantitative analysis method for isocyanato is provided through design, operation is easy, the result is accurate, and the method has popularization significance.

Description

technical field [0001] The invention relates to the analysis of melamine tail gas, in particular to a quantitative analysis method for isocyanate in melamine tail gas. Background technique [0002] There is a large amount of ammonia in the tail gas of melamine. During the titration of isocyanic acid and its esters, ammonia reacts with hydrochloric acid to form ammonium chloride. Therefore, when titrating isocyanic acid and its lipids, ammonia and its esters must be removed in advance. Salt substances, but in the current prior art, there is no effective solution to solve the above technical problems. Contents of the invention [0003] In order to solve the problems in the background technology, the invention provides a kind of quantitative analysis method of isocyanate in melamine tail gas, by proposing a kind of new quantitative analysis method, make the quantitative analysis of isocyanate in melamine tail gas more accurate, the present invention The technical scheme adop...

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
CPCG01N31/16
Inventor 王杰郭文龙王康平荆云峰谢红飞王颖和
Owner SHANXI YANGMEI FENGXI FERTILIZER IND GRPCO
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