GB/T 22228-2008Chemical products for industrial use -- Determination of vapour pressure of solids and liquids in the rang 10-1 to 105 Pa -- Static method (English PDF)

Foreword

This standard is equivalent to using NFT20-048. 1985 "industrial chemicals and 105Pa 10-1Pa range of solid and liquid vapor Static pressure measurement method "(French version).

For ease of use, has been modified following editorial.

a) delete the original standard preface;

b) use punctuation "," instead of the original standard by "*" notation;

c) the original standard 0 chapter, "Introduction" to the introduction of this standard.

This standard is managed by the National Standardization Technical Committee chemicals dangerous (SAC/TC251) and focal points.

Participated in the drafting of this standard. the Chemical Institute of standardization, Hubei Exit Inspection and Quarantine.

Drafters of this standard. Cui Hairong, Wang Xiaobing Guo Jian, Jian Mei, Cheng Ye, Zhou Wei, Ling about Tao, Zhang Jianfeng, Zhang Jun Xi Yang wind, Wang Fan.

This standard is the first release.

Introduction

Before measurement start, the proposed test, first grasp the basic information on chemicals, according to the state of the product, melting point, boiling point to be tested.

It is not possible there is a vapor pressure within each range are able to apply a method that is less than the vapor pressure range 10-3Pa ~ 105Pa, which is why the need to set up a series of test methods based on the physical state of the product of reason. These trials Party Method are summarized in Table 1 below.

Table 1 according to Rao vapor pressure range recommended methods of measurement

experiment method

product

Solid and liquid

Pressure range/Pa Repeatability/Reproducibility% /% Kinetic 103 ~ 2 × 10-3 2 × 103 ~ 105 1 to 25 1-5 Method Static X X 10-1 ~ 105b 5 ~ 10 5 ~ 10 Liquid vapor pressure meter X X 102 ~ 105 5 ~ 10 5 ~ 10 Vapor pressure balance method X X 10-3 ~ 1 5 ~ 20 50 Gas saturation method X X 1 Scope this standard was determined by a static method for industrial chemicals vapor pressure.

This standard applies to all values \u200b\u200bof the vapor pressure of solids and liquids within range to 10-1Pa ~ 105Pa.

Impurities have a certain impact on the chemical nature of the measurement, such as volatile solvents.

2 Terms and definitions

The following terms and definitions apply to this standard.

Saturation vapor pressure of solid or liquid substances, expressed in units of Pa. In the case of dynamic equilibrium thermodynamics, the vapor pressure of pure substances only take Depends on the temperature within a certain temperature range, the logarithm of the vapor pressure of the linear function is inversely proportional to temperature.

Principle 3

The standard vapor pressure measurement method is based on the thermodynamic equilibrium at a certain temperature within a closed system.

4 Reagents

4.1 nitrogen.

4.2 Mercury. for vapor pressure in the range of 102 ~ 105Pa.

4.3 silicone or phthalates. for vapor pressure in the range 10Pa ~ 102Pa.

4.4 liquid nitrogen.

4.5 dry ice.

5 Instruments