Graphite tube used for graphite furnace atomic absorption spectrophotometer and preparation method thereof

A graphite furnace atom and graphite tube technology, applied in the field of graphite tubes, can solve the problem that the anti-oxidation ability cannot meet people's expectations, etc., and achieve the effect of prolonging the service life

Inactive Publication Date: 2009-12-16
GUANGDONG INST OF ECO ENVIRONMENT & SOIL SCI
View PDF0 Cites 7 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Although the oxidation resistance of pyrolytic graphite is stronger than that of ordinary graphite...

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

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Graphite tube used for graphite furnace atomic absorption spectrophotometer and preparation method thereof
  • Graphite tube used for graphite furnace atomic absorption spectrophotometer and preparation method thereof
  • Graphite tube used for graphite furnace atomic absorption spectrophotometer and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0025] The following is a brief description of the preparation process of the graphite tube:

[0026] 1. Surface heat treatment of graphite tube

[0027] The commercially available graphite tubes are basically pyrolytic graphite tubes. Pyrolytic graphite is hydrophobic, and it must be heated (grilled) to remove the hydrophobicity, so that the metal salt solution can be evenly spread on its surface.

[0028] The method of heat treatment can be to heat the graphite tube to 2000-2500°C for air firing, or to use the formatting of the graphite tube to achieve the effect of air firing, killing two birds with one stone.

[0029] The formatting process itself is a heating process with different temperature steps from low temperature to high temperature, and this process can complete the heat treatment of the graphite tube surface. The damage to the graphite tube caused by the empty fired graphite tube is avoided.

[0030] 2. Optional metal salts

[0031] The following metal salts ...

Embodiment

[0038] Prepare graphite tubes as follows:

[0039] (1) Put a new pyrolytic graphite tube into the graphite furnace atomic absorption spectrometer, and do formatting. Remove from the instrument after cooling.

[0040] (2) Use cotton dipped in 1.5wt% lanthanum nitrate solution to smear on the pyrolytic graphite surface of the pipe body, and do not smear on the electrode contact surface. The specific treatment process is as follows: apply cotton dipped in lanthanum nitrate solution directly outside the lumen; then insert cotton into the lumen, add lanthanum nitrate solution to the cotton until it is saturated, and let the lanthanum solution penetrate into the graphite gap, after 5 minutes Take out the cotton; in order to enhance the effect, dip the cotton with lanthanum nitrate solution directly outside the lumen and apply it again.

[0041] (3) The process of adding film is completed by means of sample testing. The steps of the heating program are the same as those of the sam...

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 graphite tube which is used for graphite furnace atomic absorption spectrophotometer and a preparation method thereof, wherein, the tube body is prepared by graphite and is provided with an electrode; the tube body except the electrode is covered with a pyrolysis graphite layer which is characterized in that the pyrolysis graphite layer is covered with a layer of metal carbide with high melting point and strong antioxidation ability. The invention has simple preparation method and can prolong the service life of the graphite tube by 30% to 50%. The preparation method in the invention is not only applicable to heating the graphite tube longitudinally, but also applicable to heating the graphite tube transversely.

Description

technical field [0001] The invention relates to a graphite tube, in particular to a graphite tube used in a graphite furnace atomic absorption spectrometer and a preparation method thereof. Background technique [0002] The graphite tube is the atomizer of the graphite furnace atomic absorption spectrometer, which is a consumable material, and the component of graphite is carbon. The use cost of graphite furnace atomic absorption spectrometer is mainly the consumption of graphite tube. The graphite tubes of some imported brands are priced at nearly 1,000 yuan, and they can only measure one or two hundred samples, while the service life of domestic tubes is even shorter, and they will be scrapped after dozens of samples are made. At present, how to prolong the service life of graphite tubes and reduce the cost of using instruments is an urgent requirement of the vast number of atomic absorption users. [0003] The atomization temperature of common metal elements is generall...

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): G01N21/01G01N21/31
Inventor 卢普相李定强李芳柏毕鸿亮黄赛花
Owner GUANGDONG INST OF ECO ENVIRONMENT & SOIL SCI
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products