GB/T 1816-2019 Neutrality test for benzene-type products

AI-translated method card — human verification pending. This is not an official translation of the standard. Unclear source values remain unverified; check the original standard and product certificate before use.

Card type: Test method

1. Method number / full title / English name / replacement relationship

• Standard number: GB/T 1816—2019
• Chinese title: Neutrality test for benzene-type products
• English title: Test for neutrality of benzole products
• Replacement relationship: replaces GB/T 1816—1997 "Neutrality test for benzene-type products"
• Issued / implemented: issued on 2019-06-04, implemented on 2020-01-01
• Responsible committee: National Technical Committee for Standardization of Coal Chemical Industry (SAC/TC 469)
• Proposed by: China Iron and Steel Association

2. Scope of application and non-applicability

• This standard specifies the principle, sampling and preparation of test samples, reagents, apparatus, test procedure, and test results of the neutrality test for benzene-type products.
• Applicable to the neutrality test of benzene-type products such as crude benzene and light benzene recovered from coke oven gas, coking benzene, coking toluene, coking xylene obtained by hydrogenation and rectification, and petroleum benzene, petroleum toluene, petroleum mixed xylene, etc. produced from petroleum fractions by catalytic reforming.
• Not applicable: not provided in the available source.

3. Method principle

At room temperature, extract a quantitative test sample with a quantitative amount of water, and use the acidity or alkalinity of the extract to indicate the acidity or alkalinity of the product.

4. Reagents and materials (purity / preparation)

• 5.1 Carbon dioxide-free distilled water: prepare according to GB/T 603.
• 5.2 Phenolphthalein indicator solution: 10 g/L, prepare according to GB/T 603.
• 5.3 Methyl red indicator solution: 1 g/L, prepare according to GB/T 603.

5. Apparatus and equipment

• 6.1 Separatory funnel: volume 150 mL.
• 6.2 Glass test tube: volume 25 mL.
• 6.3 Graduated cylinder: volume 100 mL, 10 mL.

6. Recommended operating conditions

• Conduct at room temperature (see Chapter 3).
• Shaking time: shake thoroughly for 2 min (see 7.1).
• Other conditions: not provided in the available source.

7. Sampling and test sample preparation

• Sampling and preparation of benzene-type products shall be carried out in accordance with the provisions of GB/T 1999 and GB/T 4756 (see Chapter 4).

8. Analysis procedure

• 7.1 Measure 100 mL of test sample with a graduated cylinder and pour it into a separatory funnel, then measure 10 mL of carbon dioxide-free distilled water and also pour it into the separatory funnel, cover with the stopper, shake thoroughly for 2 min, and allow to stand for layer separation.
• 7.2 Pour the lower aqueous solution into a test tube, first add 2 drops of phenolphthalein indicator to the test tube; a light red or red color indicates alkalinity; if colorless, then add 2 drops of methyl red indicator to the test tube; a light red color indicates acidity, and a yellow color indicates neutrality.

9. Qualitative and quantitative determination and calculation formulas

• No calculation formula.
• Result determination (qualitative):
  • After adding 2 drops of phenolphthalein, light red or red → alkaline;
  • After adding phenolphthalein, colorless, then after adding 2 drops of methyl red, light red → acidic;
  • After adding phenolphthalein, colorless, then after adding 2 drops of methyl red, yellow → neutral.

10. Precision

Not provided in the available source.

11. Report

The test sample result is expressed as alkaline, acidic, or neutral (see Chapter 8).

12. Referenced documents

• GB/T 603 Chemical reagents — Preparation of preparations and products used in test methods
• GB/T 1999 Sampling method for coking oil products
• GB/T 4756 Standard practice for manual sampling of petroleum liquids

13. Source and verification

This page is an AI translation of the available Chinese method card. Human verification is pending. It is not an official translation of the standard. Check the source standard and product certificate before use.

14. Quick reference Q&A