GOST 26239.9-84

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  ГОСТ 26239.9-84

GOST 26239.9−84 Trichlorosilane. Method for the determination of methyl chloride, ethyl chloride, butane, isobutane, methylene chloride, chloroform, carbon tetrachloride, methyldichlorosilane, methyltrichlorosilane, chlorodimethylsilane (with Change No. 1)

GOST 26239.9−84

Group B59

STATE STANDARD OF THE USSR

TRICHLOROSILANE

Method for the determination of methyl chloride, ethyl chloride, butane, isobutane, methylene chloride, chloroform, carbon tetrachloride, methyldichlorosilane, methyltrichlorosilane, chlorodimethylsilane

Trichlorsilane. Method of methyl chloride, ethyl chloride, butane, isobutane, methylene, chloroform, carbon tetrachloride, methyltrichlorsilane, chlormethylmethylsilane determination

AXTU 1709

Date of introduction 1986−01−01

The decision of the State Committee USSR on standards on July 13, 1984 N 2491* validity installed before 01.01.86 01.01.91**
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* See the label «notes»;
** Expiration removed by Protocol No. 7−95 Interstate Council for standardization, Metrology and certification (I & C N 11, 1995). — Note the manufacturer’s database.

The Change N 1, approved and in effect as of 01.01.91 by the resolution of Gosstandart of the USSR from 26.06.90 N 1848

Change No. 1 made by the manufacturer of the database in the text ICS N 10, 1990


This standard specifies a gas chromatographic method for the determination of components in trichlorosilane in the following ranges of values of mass fraction

The method is based on separation of mixture components as they move in the carrier gas flow along the sorbent with the subsequent registration of chromatogram using a flame-ionization detector.

Mass fraction of the components calculated by the areas of peaks on the chromatogram.

1. GENERAL REQUIREMENTS

1.1. General requirements for method of analysis according to GOST 26239.0−84.

1.2. Height of the chromatographic peak should be measured with an error of less than 1 mm, and the width at half the height with an error of not more than 0.5 mm.

2. APPARATUS, MATERIALS AND REAGENTS

Chromatograph «Color-102» with a detector for thermal conductivity, ionization-flame detector with the drying system of the carrier gas 13, a vacuum system inlet 9, a cryogenic trap 10, a vacuum pump 11 and valves made of glass and PTFE 3, 4 (Fig.1).

The chromatograph is made of individual blocks, structurally unrelated. The functional connection of the chromatograph is shown in hell.1.

Damn.1. A block diagram of a chromatographic installation

A block diagram of a chromatographic installation

1 — the block of preparation of chromatographic BPH-1; 2 — the thermostat of the detector is the thermal conductivity; 3, 4 — taps made of glass and PTFE; 5 — power supply unit ionization-flame detector BPD-19: 6 — ionization-flame detector; 7 — measuring small currents IMT-05; 8, 19 — automatic potentiometer KSP-4; 9 — vacuum system inlet; 10 — cryogenic trap; 11 — vacuum pump; 12 — Dewar vessel; 13 — drying system of the carrier gas; 14 — chromatography column; 15 — thermostat chromatographic column; 16 — temperature regulator thermostat chromatographic column RT-09; 17 — regulator of thermostat temperature of the detector is the thermal conductivity of RT-17; 18 — power supply of detector is the thermal conductivity BOD-20; 20 a detector for thermal conductivity; 21 is an argon cylinder and a gear; 22 — hydrogen cylinder and a gear; 23 air cylinder and a gear (parts 1, 2, 5, 6−8, 15−20 form a chromatograph «Color-102»).

Damn.1

Temperature controllers thermostats chromatographic column and detector for thermal conductivity RT-09 RT-17 16, 17 (Fig.1) performs the installation and automatic stabilization of the required temperature in the thermostats. The operating temperature range of the regulators is broken into four sub ranges: 0−100, 100−200, 200−300, 300−400 °C, which correspond to the four positions of the switch on the front panel labeled 0, 100, 200, 300, respectively. On the front panel is a potentiometer with the limb which serves for a more accurate setting of the set temperature within each sub-band and has a scale from 0 to 100 °C. the Preset temperature is determined by summing the positions of the switch and scales on the limb of the potentiometer. To enable the blocks to translate the buttons labeled «network» and «heater», located on the front panel, in the «on» position (the «on» button is recessed, off — button is pressed).

Power supply unit ionization-flame detector BPD-19 5 (damn.1) power applied to the ionization-flame detector 6 (Fig.1), temperature control thermostats and evaporator setting and automatic stabilization of the temperature of the evaporator.

Setting the evaporator temperature to produce a potentiometer with a dial located on the front panel of the unit. The switches on the buttons labeled «network» and «power detectors».

Measuring small currents IMT-05 7 (Fig.1) is used to amplify signals ionization-flame detector 6 (Fig.1) and output signals on the automatic potentiometer KSP-4 8 (DWG.1). Measuring small currents IMT-05 is enabled by the buttons «set» and «compensation», located on the front panel of the unit. The measurements at the level of large background currents before the signal (input sample) must handle «compensation» to compensate for background current.

A power supply detector for thermal conductivity BOD-20 18 (Fig.1) is the detector of thermal conductivity 20 (Fig.1), determines the limit of measurement of the detector signal and the signal to automatic potentiometer KSP-4 19 (Fig.1). Include the power supply of the detector by heat, making sure to include the flow of carrier gas through the detector, click «network». The knobs of the current «rough» and «smooth», located on the front panel of the unit must be in the leftmost position. After the unit is installed handles «install current» supply current of the detector. The limits of measurement set by using the switch marked «scale multiplier».

The connection blocks between themselves and the thermostats produced by using the cables included in delivery of spare parts and accessories (SPTA) chromatograph.

Before installation of the gas chromatographic part of the installation prepare valves made of glass and PTFE (Fig.2), a cryogenic trap (Fig.3), bypass mode system vacuum system inlet (DWG.4), the drying system of the carrier gas (Fig.5), a chromatographic column (Fig.6), and prepare the sorbent and fill them with a chromatographic column.

For the preparation of the sorbent in a glass beaker pour 100 cmmethylene chloride and dissolved therein 3 g polymethylsiloxanes rubber SE-30 (or E-301). Then pour in a solution of 20 g of chromaton N-AW with a grain size from 0.200 to 0.250 mm. To remove from the mixture obtained solvent into the glass directs a weak stream of air (25−50 cm/min), and periodically stirred with a glass rod. The prepared sorbent should have good flowability and have no odor of solvent.

Before filling a chromatographic column with sorbent, at one end of the column insert a plug of glass wool. To prevent blowing tube and sorbent from the column during the packing and in the further operation with the burner for bench soldering glass narrow tube is doing the hauling. This end of the column is connected to a vacuum pump, and the other through a funnel poured the sorbent. Fill the column, if possible, denser. After filling the column tube of glass is inserted and the second end of the column.

Installation of the gas chromatographic part of the installation start with the block of preparation of chromatographic BPH-1 1 (DWG.1), which is used for the installation, regulation and stabilization of the costs of carrier gas (argon), hydrogen and air. For this, the balloon with argon is connected to the entrance 13* block, cylinder with air — inlet 15* and a balloon with hydrogen with an input 9*. Outputs 1* hydrogen-3* air is connected to the input of the working cell ionization-flame detector, and carrier gas (argon) output 6* unit, with the first camera of the detector of thermal conductivity. Connection make plastic tubes, available in ZIP chromatograph.
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* The numbers correspond to the labeling on the rear panel of the unit BPH-1.

The gas chromatographic part of the installation of the drying system to the ionization-flame detector manufactures telepanel, using a tube made of molybdenum glass and taps made of glass and PTFE (Fig.1 and 4). While the end of the chromatographic column constriction make output vacuum gauge 2 (Fig.4) attached to a vacuum system inlet through the transition Kovar-glass 3 (Fig.4).

A connection detector on heat conductivity with glass tubes is carried out using transition metal-glass, available in a ZIP chromatograph.

Damn.2. Crane glass and PTFE

Crane glass and PTFE

a — rod; b — head; C — sleeve; d — lock nut; d — body of the crane; e — Assembly drawing (parts a, b, C, g — fluoroplastic-4, detail d — molybdenum glass)

Damn.2

Damn.3. Cryogenic trap (molybdenum glass)

Cryogenic trap (molybdenum glass)

Damn.3

Damn.4. Vacuum system inlet

Vacuum system inlet

1 — vial of the analyzed sample; 2 — vacuum; 3 — the transition Kovar-glass; 4 — vial reference sample; 5, 6, 7, 8, 10 — taps glass and PTFE; 9 — dosing volume (items 6, 7, 8, 10 are bypass mode)

Damn.4

Damn.5. Drying of the carrier gas

Drying of the carrier gas

1, 2, 3 — taps made of glass and PTFE; 4 — trap (molybdenum glass); 5 — restored oxide of copper (granular); 6 — filter of a fabric Petryanov

Damn.5

Damn.6. Chromatography column (molybdenum glass)

Chromatography column (molybdenum glass)

Damn.6

Vacuum system inlet (DWG.4) connect the vacuum tubing to a vacuum pump. To prevent the ingress of vapor of trichlorosilane in a vacuum pump between the pump and the inlet system, put cryogenic trap 10 (Fig.1) cooled by liquid nitrogen.

Once mounted the gas chromatographic part of the installation, install costs gases: carrier gas (argon) to (35±2) cm/min, hydrogen — 30 cm/min, air (300±20) cm/min on the input unit BPH-1 via gears on the cylinders, the set pressure of argon, hydrogen, air 0,5; 0,14; 0.25 MPa (5; 1,4; 2,5 kgf/cm), respectively. The necessary expenses of argon, hydrogen and air are set by knobs located on the front panel of the unit. Measurement of flow-rate of gases is performed using a bubble flowmeter. Soap-foam flow meter is assembled from parts and accessories, which package (burette, holders, brackets, tubes, etc.) available in the spare parts thermostat chromatographic column. The flow meter is attached on the left side of the thermostat and fill it with the soap solution. When measuring the consumption of hydrogen and air flow meter is connected to the gas lines directly in front of the cell ionization-flame detector to measure the argon flow — tap 3 (Fig.1). This should be open valves 1 and 2, the drying system (Fig.5), the valve 7 the vacuum system inlet (DWG.4) and tap 3 (Fig.1). Tap 3 of the drying system (Fig.5), the valves 6, 8 of the vacuum system inlet (DWG.4) and valve 4 (Fig.1) must be closed.

When determining the gas flow rate record the time for which a soap film is displaced by gas on a certain amount of cm. The gas flow rate , cm/min calculated by the formula

. (1)

Automatic potentiometer KSP-4 according to GOST ЭД1 7164−78.

The exemplary vacuum gauge according to GOST 6521−72.

Vacuum pump HV-461 M or similar.

Analytical scale.

Portable burner for bench soldering glass.

The stopwatch according to GOST 5072−79.
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* On the territory of the Russian Federation the document is not valid. For additional information, please refer to the link. — Note the manufacturer’s database.

Argon brand HF according to GOST 10157−79 in the cylinder.

Hydrogen technical GOST 3022−80 in the cylinder.

Reducer gas cylinder DCT-1−65, 2 PCs.

Reducer gas cylinder MDF-1−65.

The Dewar Vessel.

Liquid nitrogen according to GOST 9293−74.

The technical rectified ethyl alcohol GOST 18300−87.

Ampoules made of molybdenum glass with taps made of glass and Teflon with a capacity of 50−100 cm(Fig.7).

Damn.7. The ampoule with the tap of glass and Teflon (molybdenum glass)

The ampoule with the tap of glass and Teflon (molybdenum glass)

 — the side arm of the crane

Damn.7

Methylene chloride according to GOST 9968−86, grade A.

The carbon tetrachloride.

Chloroform according to GOST 20015−74*.
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* On the territory of the Russian Federation the document is not valid. Standards 20015−88. — Note the manufacturer’s database.

Ethyl chloride according to GOST 2769−78*, mark A.
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* On the territory of the Russian Federation the document is not valid. Standards 2769−92. — Note the manufacturer’s database.

Bhutan, H. h

Isobutane, H. h

Methyl chloride with a mass fraction of main component no less than 99%.

Methyldichlorosilane with a mass fraction of main component no less than 99%.

Methyltrichlorosilane with a mass fraction of main component no less than 99%.

Chlorotrimethylsilane with a mass fraction of main component no less than 99%.

Trichlorosilane with a mass fraction of main component not less than 99.999%.

Trichlorosilane with a mass fraction of methylene chloride of not more than 1·10%.

(Changed edition, Rev. N 1).

3. PREPARATION FOR ASSAY

3.1. Definition of samples for analysis

The selection of the sample for analysis is carried out in a vial made of molybdenum glass with a tap of glass and PTFE (Fig.7), having a volume of 50−100 cm. For this ampoule vacuum to a residual pressure of 10 PA (7,5·10mm Hg.St.). Then to the lateral branch of the crane ampoules (see the devil.7) solder a tube made of molybdenum glass. The free end of the tube immersed in a container of trichlorosilane and open the tap of the vial. The sample is sucked into vakuumirovannoj vial. After that, the tap closed and trichlorosilane, the remainder in a side branch of the crane, is removed by evacuation.

The ampoule with the sample soldered to the vacuum system inlet in a vertical position with the tap down.

3.2. Preparation of sample comparison

The reference sample prepared in an ampoule made of molybdenum glass with a tap of glass and PTFE mixing trichlorosilane containing not more than 1·10% methylene chloride, with methylene chloride.

For this purpose, the ampoule is evacuated with a vacuum pump to a residual pressure of 10 PA (7,5·10mm Hg.St.) and close the valve of the vial. The ampoule is detached from the pump, and on an analytical balance to determine its mass (g). In the side-arm tap (hell.7) pour about 0.5 cm ofmethylene chloride and short-term priotkryvaya crane put it in a vial in an amount of 0.02−0.05 cm(to avoid falling into the vial of air).

Methylene chloride remaining in a side branch of the crane, drained and removed by evacuation. Weigh the vial entered into the methylene chloride (in g).

Methylene chloride in the vial is frozen with liquid nitrogen. The side-arm tap the ampoule was lowered into a container of trichlorosilane. Open the faucet and fill a vial with trichlorosilane. Tap close and the trichlorosilane from the side-wall is removed by evacuation. Vial with a mixture of weighed (g). Mass fraction of methylene chloride in the mixture (a) in percent is calculated by the formula

. (2)

Vial reference sample are soldered to the vacuum system inlet (DWG.4) in a vertical position with the tap down. The reference sample suitable for an unlimited time (until total consumption).

3.3. Regeneration of the gas drying system of the carrier

For regeneration of the drying system of the carrier gas tap 3 (Fig.5) is connected to the vacuum pump and immersed in a container of warm water (50−60 °C). The tap 3 is opened and the system is evacuated to a residual pressure of 10 PA (7,5·10mm Hg.St.). Then the faucet 3 is closed, remove the system from the water and disconnect from the vacuum pump. The regeneration of the gas drying system of the carrier is carried out at the beginning of each work shift.

3.4. The inclusion of a chromatographic installation

Before turning on the instrument units, the drying of carrier gas is placed in a pair of liquid nitrogen poured into the Dewar and set the flows of argon, hydrogen and air. To do this, open the cylinders and the gears on the input unit BPH-1 (Fig.1) set pressure specified in clause 2. Then sequentially open valves 1 and 2, the drying system (Fig.5), the valve 7 the vacuum system inlet (DWG.4) and valve 4 (Fig.1). Taps 5, 6, 8, 10 vacuum system inlet (DWG.4), the tap 3 (Fig.1) must be closed.

Include components in the following sequence: temperature controllers thermostats RT-09 RT-17 17 and 16 (Fig.1) (the temperature in the thermostat of the detector should be 150 °C), power supply unit ionization-flame detector BPD-19 5 (damn.1), measuring small currents IMT-05 7 (Fig.1), the power supply of the detector is the thermal conductivity BOD-20 18 (Fig.1) (the current bridge detector needs to be 100 mA) and automatic potentiometer KSP-4 (8 and 19 on features.1).

After the blocks are turned on, light the flame ionization-flame detector. The ignition flame is carried out by pressing the button «flame ignition», located on the side wall of thermostat columns. About the ignition flame shows lightweight cotton in the detector. To verify the presence of flame by fogging a mirror or polished metal object, brought to the output port of the detector.

Then install a cryogenic trap 10 (Fig.1) and include a vacuum pump 11 (Fig.1).

3.5. Regeneration of the chromatographic column

New chromatographic column before the analysis is carried out special training. With this purpose establish a flow of argon and air in accordance with clause 3.4 (drying system should be regenerated according to claim 3.3), but the crane 4 (Fig.1) leave it closed. Include temperature controllers thermostat detector 17 (Fig.1) and thermostat chromatographic column 16 (Fig.1). The temperature in the thermostat of the detector is set equal to (150±1) °C and the thermostat chromatographic column (200±1) °C. In these conditions, a chromatographic column maintained for 4−5 h and Then close the valve 3 (Fig.1) reduce the temperature on the thermostat to the chromatographic column (120±1) °C and the column purged with argon for 7−8 h.

4. ANALYSIS

4.1. After preparation in accordance with the PP.3.3 and 3.5 chromatographic installation output the following operation:

4.2. To enter sample open valves 5 and 10 (Fig.4). After reaching the vacuum system pressure 10 PA (7,5·10mm Hg.St.) the crane 5 (Fig.4) close down. Priotkryvaya tap the vial to be analyzed by the sample 1 (Fig.4) in the inlet to vacuum gauge 2 (Fig.4) set the pressure of 50000 PA (375 mm Hg.St.). Close the valve 10 (Fig.4), which cuts off the dosing volume. Open the valve 8 (Fig.4), then simultaneously close the valve 7 and open the valve 6 (Fig.4) and immediately include stopwatch. After these steps, the analytical linkage is introduced into a chromatographic column and starts recording chromatograms. Below the words «registration of chromatogram», if not made special reservations, refers to the simultaneous recording of chromatograms at auto potentiometer 8 (Fig.1) connected to an ionization-flame detector and the automatic potentiometer 19 (Fig.1) connected to the detector of thermal conductivity.

During the registration process chromatograms it records the actual retention time (time from the moment you enter the analytical sample in a chromatographic column until the maximum of the corresponding chromatographic peak) and the indicator of the scale of the potentiometer IMT-05, in which this peak recorded in the chromatogram.

4.3. Check each peak on the chromatogram should be conducted in this switch position potentiometer IMT-05 7 (Fig.1), which provides a record of the peak in the optimal interval scale automatic potentiometer KSP-4.

With this purpose, the first linkage is used to write a preliminary chromatogram. When this record for each chromatographic peak pick a switch position potentiometer IMT-05, in which the height of the chromatographic peak is from 40% to 100% scale automatic potentiometer KSP-4.

4.4. Due to the fact that getting a large amount of trichlorosilane in the ionization-flame detector degrades the stability of its work, the main part of the strip of trichlorosilane should be given by an ionization-flame detector, switching valves 3 and 4 (Fig.1). Time yield of trichlorosilane at the moment of switching of the taps is determined using a detector of the thermal conductivity and the automatic potentiometer 19 (Fig.1). Cranes switch, when the automatic potentiometer 19 (Fig.1) start to record peak corresponding to trichlorosilane. After this automatic potentiometer graduated from the record peak of trichlorosilane, taps 3 and 4 (Fig.1) switch in the opposite direction.

4.5. After recording preliminary chromatogram cranes return in the provisions referred to in paragraph 3.4, and repeating the operation set forth in claim 4.2, insert one mounting of the sample and record the chromatogram. Then impose two sample tests and for each recorded chromatogram. Three chromatograms registered after the preliminary use, as described below, for receiving the first, second and third results of parallel measurements — the mass fraction of each of the designated components in the sample.

4.6. Then record the chromatogram of the reference sample. To this end, the cranes return in the provisions referred to in paragraph 3.4, and open valves 5 and 10 (Fig.4). The input material of the reference sample into a chromatography column and recording chromatogram of sample comparisons carried out analogously to the input of the analytical sample of the sample and registering its chromatogram (PP.4.2; 4.3; 4.4), but in this case, after pressure in the vacuum system inlet reaches 10 PA (7,5·10mm Hg.St.) and closed the crane 5 (Fig.4), slightly open the valve on the vial of reference sample 4 (Fig.4). The pressure in the vacuum system inlet shall be installed 50000 PA (375 mm Hg.St.).

Get first a preliminary chromatogram of the reference sample as specified in clause 4.3, and then another three chromatograms.

Three chromatograms of the reference sample, was after prior use in processing the results as described in section 5.2.

4.7. For identification (detection of substances that give each peak) it is necessary to know retention time of oxygen. For this purpose, recorded the chromatogram of the air samples.

The chromatographic valves installation in return provisions given in paragraph 3.4, open valves 5 and 10 (Fig.4). After reaching the vacuum system inlet pressure 10 PA (7,5·10mm Hg.St.) the crane 5 (Fig.4) closed, removed from the side-wall of the crane 5 (Fig.4) the vacuum hose leading to the vacuum pump and open the tap 5 (Fig.4) in the vacuum system inlet introduced air. The crane 5 (Fig.4) shut, put on his vacuum hose. Then close the valve 10 (Fig.4), a portion of the air according to claim 4.2 is introduced into a chromatographic column and record the chromatogram. Recorded only the peak corresponding to oxygen.

5. PROCESSING OF THE RESULTS

5.1. Identification of chromatographic peaks is performed by comparing the relative retention times obtained experimentally, with tabular values (table.1). The experimental value of the relative retention time () for each of the defined components is calculated by the formula

, (3)

where is the retention time of the component was found in the chromatogram obtained with ionization-flame detector;

the retention time of trichlorosilane, was found in the chromatogram obtained with the detector of thermal conductivity.

 — the retention time of oxygen was found in the chromatogram obtained with ionization-flame detector;

 — the retention time of oxygen was found in the chromatogram obtained with the detector of the thermal conductivity, p

Table 1

5.2. Mass fraction -th component () in the sample in percentage (each of the three results of parallel measurements) is calculated according to the formula

, (4)

where is the coefficient of relative sensitivity for the th component (table.2), dimensionless quantity;

 — the area of the chromatographic peak -th component on the chromatogram, mm, was found in one of the three chromatograms obtained with ionization-flame detector;

here height (mm) of this chromatographic peak;

 — width (mm) of this peak at half its height;

 — the area of the chromatographic peak (mm) methylene chloride in the reference sample, calculated as the arithmetic average of the three values found for the three chromatograms sample comparisons obtained with ionization-flame detector;

here height (mm);

 — the width at half height (mm) of the chromatographic peak of the methylene chloride is measured for one of the three chromatograms;

 — mass fraction of methylene chloride in the reference sample (p.3.2) percentage;

,  — indicators of the scale of potentiometer IMT-05 (for example, 100 to 100 scale·10A), for -th component (I.4.8) and methylene chloride (p.4.6), respectively, dimensionless value.

The result of analysis in percent is calculated as the arithmetic average of the three results of parallel measurements

. (5)

Table 2

The values of the coefficients of relative sensitivity (KOCH)

5.3. The difference between the highest and lowest of the three results of parallel measurements with a confidence probability of 0.95 does not exceed the permissible values of absolute differences are given in table.3.

Table 3

5.4. Validation of the analysis carried out by analyzing synthetic sample with a known mass fraction of the designated component. A synthetic sample prepared similarly to the reference sample (p.3.2) mixing trichlorosilane with one or more of the following substances: methyl chloride, butane, isobutane, ethyl chloride, methylene chloride, chloroform, carbon tetrachloride, methyldichlorosilane, methyltrichlorosilane, chlorodimethylsilane.

The analysis is considered correct if condition is met

, (6)

where  — mass fraction of th component in the synthetic sample, a well-known procedure of its preparation, %;

 — experimentally found value of mass fraction of th component (result of analysis), %;

 — allowable absolute difference of results of three parallel measurements taken at the table.3 for the mass fraction of the designated -th component, equal , %

.

5.5. In case of contact with trichlorosilane in an ionization-flame detector or after 30−40 tests this detector is switched off, dismantled and washed with a cotton swab moistened with ethyl alcohol. After washing the detector are checking the correct operation of the installation.

To control the correct operation of the unit analyzing the reference sample, defining it as in the sample, mass fraction of methylene chloride (PP.4.2−4.6; 5.2). Thus in the calculation formula (4) substitute numerical values and obtained for this sample comparison earlier, when there was no reason to believe that the unit operates incorrectly, the values and in accordance with clause 5.2, where the -th component of a sample of methylene chloride, and the value explained below. Installation works correctly, if

, (7)

where is the experimentally found value of mass fraction of methylene chloride in the reference sample (the test result), %;

 — mass fraction of methylene chloride in the same sample comparison, the known procedure of cooking, %;

 — permissible divergence of the results of three parallel measurements (see table.3) for the mass fraction of methylene chloride, equal , %.