Unlock instant, AI-driven research and patent intelligence for your innovation.

Method for determining content of formaldehyde in liquid

A formaldehyde content, liquid technology, applied in the direction of material analysis by observing the influence of chemical indicators, and analysis by chemical reaction of materials, etc., can solve the problem that the quality cannot be guaranteed, the color phenomenon is not obvious, and it is not easy to operate safely. and other problems, to achieve the effects of low cost, fast color reaction, and loose measurement conditions.

Inactive Publication Date: 2016-05-25
田琳琳
View PDF0 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

At present, there are several corresponding detection methods for the rapid detection of formaldehyde in liquids such as raw milk, but the quality cannot be guaranteed due to the disadvantages of unsafe operation, inconspicuous color development, or low sensitivity.

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

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0014] The invention relates to a method for measuring formaldehyde content in a liquid, comprising the following steps: (1) taking 10 g of the liquid to be tested and centrifuging it on a high-speed centrifuge to obtain an upper layer;

[0015] (2) Get the above upper layer liquid, transfer it to an ultrafiltration cup, use an ultrafiltration membrane to ultrafilter with an ultrafilter at room temperature, collect the filtered colorless clear liquid, and store it at minus 10 degrees for measurement;

[0016] (3) Add formaldehyde chromogen to a clean ultraviolet cuvette;

[0017] (4) Weigh 10g of sodium hydroxide in a volumetric flask, then add 20ml of distilled water, shake well and add to the above-mentioned UV cuvette;

[0018] (5) Take another 0.1 mg of colorless clear solution, gradually add it to the UV cuvette with a micro-injector, add the formaldehyde chromogen while adding the sample, let it stand for 20 minutes, and then detect it on the UV-Vis spectrophotometer cr...

Embodiment 2

[0020] The invention relates to a method for measuring formaldehyde content in a liquid, comprising the following steps: (1) taking 10 g of the liquid to be tested and centrifuging it on a high-speed centrifuge to obtain an upper layer;

[0021] (2) Get the above upper layer liquid, transfer it to an ultrafiltration cup, use an ultrafiltration membrane to ultrafilter with an ultrafilter at room temperature, collect the filtered colorless clear liquid, and store it at minus 10 degrees for measurement;

[0022] (3) Add formaldehyde chromogen to a clean ultraviolet cuvette;

[0023] (4) Weigh 15g of sodium hydroxide in a volumetric flask, then add 28ml of distilled water, shake well and add to the above-mentioned UV cuvette;

[0024] (5) Take another 0.1 mg of colorless clear liquid, gradually add it to the UV cuvette with a micro-injector, add the formaldehyde chromogenic reagent while adding the sample, let it stand for 30 minutes, and then detect it on the UV-visible spectroph...

Embodiment 3

[0026] The invention relates to a method for measuring formaldehyde content in a liquid, comprising the following steps: (1) taking 10 g of the liquid to be tested and centrifuging it on a high-speed centrifuge to obtain an upper layer;

[0027] (2) Get the above upper layer liquid, transfer it to an ultrafiltration cup, use an ultrafiltration membrane to ultrafilter with an ultrafilter at room temperature, collect the filtered colorless clear liquid, and store it at minus 10 degrees for measurement;

[0028] (3) Add formaldehyde chromogen to a clean ultraviolet cuvette;

[0029] (4) Weigh 12g of sodium hydroxide in a volumetric flask, then add 24ml of distilled water, shake well and add to the above-mentioned UV cuvette;

[0030] (5) Take another 0.1 mg of colorless clear solution, gradually add it to the UV cuvette with a micro-injector, add the formaldehyde color reagent while adding the sample, let it stand for 25 minutes, and then detect it on the UV-visible spectrophotom...

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 discloses a method for determining the content of formaldehyde in liquid. The method comprises the following steps: taking 10g of liquid to be detected and centrifuging on a high-speed centrifuging machine to obtain supernatant; taking the supernatant and transferring the supernatant into an ultrafiltration cup; carrying out ultrafiltration by using an ultrafiltration membrane through an ultra-filter under a room temperature condition; taking filtered-out colorless clear liquid; preserving the liquid at -10 DEG C for measurement; adding a formaldehyde color developing agent into a clean ultraviolet cuvette; weighing 10g to 15g of sodium hydroxide and putting the sodium hydroxide into a volumetric flask; adding 20ml to 28ml of distilled water, and uniformly shaking; adding the mixture into the ultraviolet cuvette; taking 0.1mg of the colorless clear liquid and gradually adding the colorless clear liquid into the ultraviolet cuvette by using a trace sample feeding device; adding the sample and adding the formaldehyde color developing agent at the same time; standing for 20 to 30 minutes and detecting on an ultraviolet visible light spectrophotometer to judge a result. The method disclosed by the invention is rapid in developing reaction; determination conditions are relatively not strict; the method is high in sensitivity and low in cost, and has small interferences in a detection process; with regard to large-size and middle-size dairy enterprises or beverage enterprises, the method for rapidly determining the content of the formaldehyde in the liquid, disclosed by the invention, is very suitable for popularization.

Description

technical field [0001] The invention relates to a detection method, in particular to a method for measuring formaldehyde content in liquid, and belongs to the field of safety detection. Background technique [0002] At present, the phenomenon of adulteration of raw milk in our country has been repeatedly banned, and it is becoming more and more serious and common. Because formaldehyde has anti-corrosion and disinfection effects, driven by profit, some dairy farmers add formaldehyde to raw milk to achieve the microbial index when receiving milk. No one knows that formaldehyde is a highly toxic substance. Formaldehyde is on the priority control list of toxic chemicals in my country. Ranked second. Formaldehyde has been determined by the World Health Organization as a carcinogenic and teratogenic substance. It is a recognized source of allergies and one of the potential strong mutagens. It can destroy biological cell proteins and cause human allergies, intestinal irritation, an...

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): G01N21/78
CPCG01N21/78
Inventor 田琳琳
Owner 田琳琳