semi合集-English.pdf - 第4802页
SEMI C58-0305 © SEMI 2005 3 9.1.2.4 Temperatures: Detector 280 C Column Oven 60 C Methanizer 350 C 9.1.3 Calibration S tandards — 0.5–2. 5 ppm (mol/mol ) carbon m onoxide, 0.5–2.5 ppm (mol/mol) carbon dioxide, bala…
SEMI C58-0305 © SEMI 2005 2
Table 1 Impurity and Other Requirements for Various Grades of Hydrogen
Previous SEMI Reference # C3.19-0200
(Specification)
C3.30-0999
(Specification)
Grade 5.5 5.7
Purity 99.9995% 99.9997%
#1
Impurities Maximum Acceptable Level (ppm)
#2
Carbon Dioxide (CO
2
) 0.5 0.2
Carbon Monoxide (CO) 0.5 0.2
Nitrogen (N
2
) 2 2
Oxygen (O
2
) 0.5 0.2
Total Hydrocarbons expressed as Methane (THC) 0.5 0.2
Water (H
2
O) (v/v) 0.5 0.2
TOTAL SPECIFIED IMPURITIES 4.5 2.8
Particles
#3
#3
#1
A purifier is allowed to be used to meet this specification.
#2
An analysis of significant figures has not been considered. The number of significant figures is based on analytical accuracy and the precision
of the provided procedure.
#3
To be determined between supplier and user.
8 Physical Constants
8.1 The physical constants of hydrogen are given in Table 2 (for information only).
Table 2 Physical Constants of Hydrogen (for information only)
Metric Units US Units
Molecular weight 2.016 2.016
Boiling point at 1 atm
–252.7C –423.0F
Density of gas at 21.1C (70F)
and 1 atm
0.0834401 kg/m
3
0.005209 lb/ft
3
Specific gravity of gas at 21.1C
and 1 atm (air = 1)
0.06950 0.06950
Density of liquid at boiling point 68.6 kg/m
3
4.28 lb/ft
3
9 Analytical Procedures for Grade 5.5 Hydrogen
NOTE 1: Introduce the calibration standard as many times as necessary to achieve the desired precision.
NOTE 2: All gases used in the analysis of the sample should contain no more than 10% of the sample value of the component of
interest unless otherwise specified.
9.1 Carbon Monoxide and Carbon Dioxide — This procedure is for the determination of carbon monoxide and
carbon dioxide in hydrogen using a gas chromatograph with a flame ionization detector and methanizer.
9.1.1 Detection Limit — 100 ppb (mol/mol).
9.1.2 Instrument Parameters
9.1.2.1 Column: Porapak T or Q, 3 m (9.8 ft) by 3 mm (1/8 in) ID by 2.2 mm (0.085 in) OD stainless steel; or
Chromosorb 102, 2 m (6.6 ft) by 3 mm stainless steel; or equivalent
9.1.2.2 Carrier Flow: 30 mL/min helium.
9.1.2.3 Sample Volume: 0.5 to 2.0 mL.
SEMI C58-0305 © SEMI 2005 3
9.1.2.4 Temperatures:
Detector
280C
Column Oven
60C
Methanizer
350C
9.1.3 Calibration Standards — 0.5–2.5 ppm (mol/mol) carbon monoxide, 0.5–2.5 ppm (mol/mol) carbon dioxide,
balance hydrogen.
9.1.4 Operating Procedure
9.1.4.1 Inject the calibration standard into the column using a gas sampling valve. Record the retention times and
peak areas. The order of elution is carbon monoxide, carbon dioxide.
9.1.4.2 Inject the sample to be tested in same manner as the calibration standard. Record the retention times and
peak areas.
9.1.4.3 Repeat ¶9.1.4.1.
9.1.4.4 Compare the average peak areas of the calibration standard to that of the hydrogen sample being tested.
Calculate the concentrations of carbon monoxide and carbon dioxide, using the formula below.
9.1.4.5 The result may not exceed the specification in Table 1.
9.2 Nitrogen — This procedure is for the determination of nitrogen in hydrogen using a gas chromatograph with a
helium ionization detector.
9.2.1 Detection Limit — 500 ppb (mol/mol).
9.2.2 Instrument Parameters
9.2.2.1 Column: 5A molecular sieve 1.9 m (6 ft) by 3.2 mm (1/8 in) OD by 2.2 mm (0.085 in) ID by stainless steel
or equivalent.
9.2.2.2 Carrier Flow: 30 mL/min helium.
9.2.2.3 Sample Volume: 3.0 mL.
9.2.2.4 Temperatures:
Detector
125C
Column Temperature
65C
9.2.3 Calibration Standard — 0.5–2.5 ppm, (mol/mol) nitrogen in hydrogen.
9.2.4 Operating Procedure
9.2.4.1 Inject the calibration standard into the column using a gas sampling valve. Record the retention times and
peak areas.
9.2.4.2 Inject the sample to be tested in same manner as the calibration standard. Record the retention times and
peak areas.
9.2.4.3 Repeat ¶9.2.4.1.
Sample Peak
Area
Standard Peak Area
Concentration
of Standard
Concentration
of Sample
SEMI C58-0305 © SEMI 2005 4
9.2.4.4 Compare the average peak area of the calibration standard to that of the hydrogen sample being tested.
Calculate the concentration of nitrogen, using the formula below.
9.2.4.5 The result may not exceed the specification in Table 1.
9.3 Oxygen — This procedure is for the determination of oxygen in hydrogen using a continuous flow analyzer
using an electrochemical method.
9.3.1 Detection Limit — 100 ppb (mol/mol)
9.3.2 Flow Rate — Set sample flow rates in accordance with the instrument manufacturer’s instructions.
9.3.3 Calibration Standard — 0.5–2.5 ppm (mol/mol) oxygen in hydrogen or in accordance with the instrument
manufacturer’s instructions.
9.3.4 Operating Procedure
9.3.4.1 Do not change the initial sample flow setting once established.
9.3.4.2 Introduce hydrogen sample and record oxygen reading. The result may not exceed the specification in
Table 1.
9.4 Total Hydrocarbons — This procedure is for the determination of total hydrocarbons in hydrogen using a
continuous flow flame ionization detector equipped total hydrocarbon analyzer.
NOTE 3: The 0–1 range can be used provided that zero and span gas standards in hydrogen with known levels of hydrocarbons
between 0 and 1 ppm are used in the calibration of the analyzer.
NOTE 4: As the flow rate and heat capacity of the matrix gas affect the instrument output, the zero gas matrices should be
coincided with that of the sample gas.
NOTE 5: The effective response of a flame ionization detector-equipped total hydrocarbon analyzer to different hydrocarbons
can vary and must be approximated. However, the response of the common hydrocarbon impurities in hydrogen can be
accurately totaled and compared to methane.
9.4.1 Detection Limit — 0.1 ppm (mol/mol).
9.4.2 Flow Requirements
9.4.2.1 High purity, hydrocarbon-free (less than 0.1 ppm) hydrogen: 35–40 mL/min or 40% hydrogen in either
helium or nitrogen matrix at 75–80 mL/min.
9.4.2.2 Dry, hydrocarbon-free (less than 0.1 ppm) air: 350–400 mL/min.
9.4.2.3 Set sample flow rates in accordance with the instrument manufacturer’s instructions.
9.4.3 Calibration Standards
9.4.3.1 Zero hydrogen with known quantity of hydrocarbons at 0.1 ppm level.
9.4.3.2 The upper level span gas not exceeding five times the concentration of the specification.
9.4.4 Operating Procedure
9.4.4.1 Do not change the initial flow settings for hydrogen, air and sample once established.
9.4.4.2 Introduce the zero hydrogen with known quantity of hydrocarbons and using the 0–10 ppm range, set the
needle (or output) to read the correct level using the zero adjust knob.
9.4.4.3 Introduce the span gas standard in hydrogen and using the span adjust knob, set the needle (or output
reading) to match the level of hydrocarbons in the span gas.
9.4.4.4 Repeat ¶9.4.4.2 and ¶9.4.4.3 until reproducibility of readings is better than 1% full scale.
9.4.4.5 Introduce hydrogen sample into the analyzer and read the quantity of hydrocarbons on the analyzer meter.
The result may not exceed the specification in Table 1.
Sample Peak
Area
Standard Peak Area
Concentration
of Standard
Concentration
of Sample