Method for measuring content of halogen

Abstract

The invention relates to the field of analysis and testing, in particular to a method for measuring the content of halogen. Requirements on the accuracy of measuring the content of the chlorine ions and the content of the bromonium ions in products become higher and higher along with the constant deepening of non-halogenated requirements on industrial products. In the process of measuring the content of chlorine and the content of bromine in products, the invention makes improvement on the stage of processing a sample by the oxygen bomb combustion method, adding iodine ions into the existing absorption liquid so as to convert silver chloride precipitation and silver bromide precipitation into silver iodide precipitation, thereby enabling that the chlorine ions and the bromonium ions are free, facilitating the rear measurement of the chlorine content and the bromine content in products by utilizing ion chromatograph, and increasing the accuracy of detection.

Description

technical field

[0001] The invention belongs to the field of analysis and testing, and specifically refers to a method for measuring halogen content. Background technique

[0002] With the deepening of industrial halogen-free requirements, the requirements for the accuracy of chlorine and bromine tests in products are also getting higher and higher. The current detection methods use the standard EN 14582: 2007 for sample processing, and then use ion chromatography For quantitative analysis, the sample processing method in the standard is described as follows: the sample is oxidized by combustion in a closed system (a calorimeter bomb containing high-pressure oxygen), and the compounds containing chlorine and bromine are respectively converted into chloride and bromide, and then oxidized by Absorption Solution Absorbs and / or dissolves in the absorption solution.

[0003] Since the absorbent is Na 2 CO 3 / NaHCO 3 Therefore, only soluble chlorine and bromine can be dissolve...

Examples

Embodiment 1

[0027] Sample processing stage:

[0028] 1. Sample weighing: Weigh 1g of the sample (accurate to 0.0001g) into the sample cup of the oxygen bomb, and then add 0.6ml of conventional combustion accelerant into the cup, but the total amount of the sample and accelerant shall not exceed 1.5g.

[0029] 2. Install the ignition wire and sample: open the cover of the oxygen bomb, fix the sample cup containing the sample, and fix the two ends of an ignition wire with a suitable length on the electrode column, and make it contact with the sample without touching the sample cup;

[0030] 3. Add absorption liquid:

[0031] a) Preparation of absorption liquid: Na in the absorption liquid 2 CO 3 Concentration 0.8mmol / l, NaHCO 3 The concentration is 1.5mmol / l, the concentration of sodium iodide is 20mmol / l, mix thoroughly and evenly, and make iodide-containing absorption liquid.

[0032] b) Addition of absorbing liquid: add 15ml of iodide-containing absorbing liquid into the oxygen bomb ...

Embodiment 2

[0042] Sample processing stage:

[0043] 1. Sample weighing: Weigh 0.8g of the sample (accurate to 0.0001g) into the sample cup of the oxygen bomb, and then add 0.3ml of conventional combustion accelerant into the cup, but the total amount of the sample and accelerant shall not exceed 1.5g.

[0044] 2. Install the ignition wire and sample: open the cover of the oxygen bomb, fix the sample cup containing the sample, and fix the two ends of an ignition wire with a suitable length on the electrode column, and make it contact with the sample without touching the sample cup;

[0045] 3. Add absorption liquid:

[0046] a) Preparation of absorption liquid: Na in the absorption liquid 2 CO 3 Concentration 1.0mmol / l, NaHCO 3 The concentration is 2.0mmol / l, and the concentration of potassium iodide is 30mmol / l, and they are thoroughly mixed to prepare an iodide-containing absorption solution.

[0047] b) Addition of absorbing liquid: add 18ml of iodide-containing absorbing liquid in...

technical field

[0001] The invention belongs to the field of analysis and testing, and specifically refers to a method for measuring halogen content. Background technique

[0002] With the deepening of industrial halogen-free requirements, the requirements for the accuracy of chlorine and bromine tests in products are also getting higher and higher. The current detection methods use the standard EN 14582: 2007 for sample processing, and then use ion chromatography For quantitative analysis, the sample processing method in the standard is described as follows: the sample is oxidized by combustion in a closed system (a calorimeter bomb containing high-pressure oxygen), and the compounds containing chlorine and bromine are respectively converted into chloride and bromide, and then oxidized by Absorption Solution Absorbs and / or dissolves in the absorption solution.

[0003] Since the absorbent is Na 2 CO 3 / NaHCO 3 Therefore, only soluble chlorine and bromine can be dissolve...

Examples

Embodiment 1

[0027] Sample processing stage:

[0028] 1. Sample weighing: Weigh 1g of the sample (accurate to 0.0001g) into the sample cup of the oxygen bomb, and then add 0.6ml of conventional combustion accelerant into the cup, but the total amount of the sample and accelerant shall not exceed 1.5g.

[0029] 2. Install the ignition wire and sample: open the cover of the oxygen bomb, fix the sample cup containing the sample, and fix the two ends of an ignition wire with a suitable length on the electrode column, and make it contact with the sample without touching the sample cup;

[0030] 3. Add absorption liquid:

[0031] a) Preparation of absorption liquid: Na in the absorption liquid 2 CO 3 Concentration 0.8mmol / l, NaHCO 3 The concentration is 1.5mmol / l, the concentration of sodium iodide is 20mmol / l, mix thoroughly and evenly, and make iodide-containing absorption liquid.

[0032] b) Addition of absorbing liquid: add 15ml of iodide-containing absorbing liquid into the oxygen bomb ...

Embodiment 2

[0042] Sample processing stage:

[0043] 1. Sample weighing: Weigh 0.8g of the sample (accurate to 0.0001g) into the sample cup of the oxygen bomb, and then add 0.3ml of conventional combustion accelerant into the cup, but the total amount of the sample and accelerant shall not exceed 1.5g.

[0044] 2. Install the ignition wire and sample: open the cover of the oxygen bomb, fix the sample cup containing the sample, and fix the two ends of an ignition wire with a suitable length on the electrode column, and make it contact with the sample without touching the sample cup;

[0045] 3. Add absorption liquid:

[0046] a) Preparation of absorption liquid: Na in the absorption liquid 2 CO 3 Concentration 1.0mmol / l, NaHCO 3 The concentration is 2.0mmol / l, and the concentration of potassium iodide is 30mmol / l, and they are thoroughly mixed to prepare an iodide-containing absorption solution.

[0047] b) Addition of absorbing liquid: add 18ml of iodide-containing absorbing liquid in...