Lab Ultra-low Saturated Vapor Pressure Analyzer 

Product description:

With the rapid development of petrochemicals, pharmaceutical environmental protection and other fields, researchers have more and more demand for low steam pressure data. Such as pesticides, storage of chemical fertilizers, manufacturing of flavors, and prolonged life of plasticizers in rubber and plastic. The design and development of these products requires pure substance low steam pressure data, so testing low steam pressure is of great significance.

Product introduction

With the rapid development of petrochemicals, pharmaceutical environmental protection and other fields, researchers have more and more demand for low steam pressure data. Such as pesticides, storage of chemical fertilizers, manufacturing of flavors, and prolonged life of plasticizers in rubber and plastic. The design and development of these products requires pure substance low steam pressure data, so testing low steam pressure is of great significance.

The status quo is that most steam pressure data is concentrated in the range of dozens of paa or above. There are very few low -voltage and ultra -low -voltage data. How to accurately test pure substance low steam pressure data is exactly what this instrument can do for everyone.

The BSD-PWP ultra-low steam pressure analyzer is a research-level analysis instrument, which is tested by the principle of Knudsen Effusion Quality Method.

Test principle

At present, the methods commonly used to measure low vapor pressure include flow escape method, Knudsen torque gap penetration method and Knudsen mass gap penetration method.

The basic principle of Knudsen gap penetration method is that the measured material is placed in a Knudsen box, outside the box is a high vacuum (absolute pressure is less than 10-2P a). When heated to a certain temperature, the vapor diffusion of the sample reaches a dynamic equilibrium, and the vapor molecules will diffuse outward from the keyhole at a constant rate. The vapor pressure of the substance can be calculated by measuring the diffusion rate of the diffused gas, dm /d t, or the vapor pressure of the substance can be calculated by measuring the rotation Angle caused by the torsional moment of the diffused gas. The former is called Knudsen mass gap penetration method and the latter is called Knudsen torque gap penetration method.

To accomplish the above diffusion, Knudsen diffusion conditions must be satisfied: (a) the external pressure tends to zero; (b) Very thin pore walls i.e. very short pore channels; (c) the vapor pressure of the measured substance is low (generally less than 1P a); (d) The average degree of freedom of a gas molecule is sufficiently long.

Knudsen mass gap penetration method is suitable for the determination of low vapor pressure, especially for the determination of some difficult solid vapor pressure at high temperature. The Knudsen mass gap penetration method is one of the widely used methods to measure low steam pressure, with the upper limit of pressure measurement being 100P a and the lower limit of pressure measurement being 10-3P a.

Performance parameter

 Advantages and characteristics

Two-mode buoyancy correction: Mode 1: buoyancy calculation mode Mode 2: background deduction curve mode

Segmented pressure measurement: dual pressure sensor; Segment test: 0-1torr, 0-1000torr; The original imported capacitance film pressure sensor, the reading accuracy error is less than 0.15%, the highest accuracy of the current pressure sensor; The segmented pressure sensor configuration can obtain higher accuracy for the adsorption test and analysis of steam adsorbent with low saturated vapor pressure at room temperature. Compared with the single pressure sensor, the test accuracy is more than 2 orders of magnitude higher;

Imported vacuum pump: Germany imported two-stage direct vacuum pump, low noise, long life. (Molecular pump is optional)

Quartz wire insulation seal: the pressure, temperature and other sensor signals in the vacuum chamber adopt the current international high standard quartz wire insulation seal technology, the leakage rate is very low, aging resistance, strong stability;

Intelligent automatic calibration: air tightness automatic detection process, intelligent judgment instrument air tightness is qualified;