CN103969201A - Measuring method for total chrome in groundwater - Google Patents

Abstract

The invention relates to a measuring method for total chrome in groundwater. The measuring method comprises the following steps: (1) 0 ug/L, 10 ug/L, 20 ug/L, 30 ug/L and 40 ug/L of a series of standard samples are prepared; (2) samples are the groundwater, the measuring is carried out by absorbing 20 uL of the samples and a series of standard samples; (3) an Agilent atomic absorption spectrophotometer 3511 graphite furnace system is adopted as an experimental instrument, the instrument is adjusted to be in the optimum state, and the experiment is conducted after the instrument is stabilized; (4) an argon gas source and a water source are opened, and the pressure of the argon gas is adjusted to 0.3 MPa; (5) parameters in the experiment are set; (6) at the wavelength of 357.8 nm, the blank zero setting is conducted, the standard curve is drew, the absorbance of the samples is measured, the corresponding chromium content of the samples can be measured from the standard curve, and the unit is ug/L. Compared with the prior art, the measuring method has the benefits as follows: the method detection limit is low, so that the measuring method is more suitable for the monitoring of the total chrome in the groundwater; meanwhile, the detection process is simple, the operation is easy, and the detection accuracy is high, so that the measuring method is suitable for popularization and application.

Description

The assay method of total chromium in a kind of underground water

Technical field

The present invention relates to groundwater monitoring technical field, relate in particular to the assay method of total chromium in a kind of underground water.

Background technology

Total chromium is one of groundwater monitoring index, the detection method national standard using at present has potassium permanganate oxygen--diphenyl carbazide spectrophotometry and ferrous sulphate titrimetry, and its measurement range is respectively concentration limit to be 0.004mg/l and to be greater than being suitable for of 1mg/l.In underground water, total chrome content is atomic, substantially can detect out with chemical determination, therefore needs to study the assay method of total chromium in a kind of more applicable underground water.

Summary of the invention

The present invention overcomes the deficiencies in the prior art, a kind of method that adopts flameless atomic absorption spectrometry to measure total chromium in underground water is provided, has greatly reduced method detection limit (0.003mg/l), easy and simple to handle, accuracy is high, has met the needs of groundwater monitoring.

In order to achieve the above object, the present invention realizes by the following technical solutions:

In underground water, an assay method for total chromium, comprises the steps:

1) draw 1mg/L chromium standard and use solution 0mL, 1.0mL, 2.0mL, 3.0mL, 4.0mL, be placed in 100mL volumetric flask, with volume ratio be 1 part of nitric acid: the salpeter solution of 99 parts of distilled water is diluted to scale, shake up, be mixed with the standard series sample of 0ug/L, 10ug/L, 20ug/L, 30ug/L, 40ug/L;

2) sample is underground water, draws 20uL sample and standard series sample measure with 20ul microsyringe;

3) use Agilent atomic absorption spectrophotometer (AAS) 3511 graphite furnace systemic effect experimental apparatuss, regulate instrument to optimum condition, after instrument stabilizer, test instrument condition of work:

Wavelength: 357.8nm;

Lamp current: 2.0mA;

Slit: 0.2nm;

4) open argon gas source of the gas and water source, argon pressure is adjusted to 0.3MPa;

5) parameters setting in experiment:

Drying stage: 90～100 DEG C of 10～15 minutes retention times 15～20 minute heating-up time of temperature

The ashing stage: 680～720 DEG C of 15～20 minutes retention times 15～20 minute heating-up time of temperature

Atomized stage: 2800～3000 DEG C of 5～6 minutes retention times 1～2 minute heating-up time of temperature

Wash phase: 2900～3100 DEG C of 3～4 minutes retention times 2～3 minute heating-up time of temperature

6), under the best operating condition of instrument, in wavelength 357.8nm place, with blank zeroing, survey its absorbance; Taking measure absorbance as ordinate, corresponding chromium content is horizontal ordinate, drawing standard curve; Press the equal instrument condition of typical curve, with blank zeroing, measure the absorbance of sample, try to achieve the corresponding chromium content of sample, the ug/l of unit from typical curve.

Compared with prior art, the invention has the beneficial effects as follows:

1) method detection limit is low, is more suitable for the monitoring of total chromium in underground water;

2) experimentation is simple, easily operation;

3) inspection accuracy is high, is applicable to applying.

Embodiment

In underground water, an assay method for total chromium, comprises the steps:

1) draw 1mg/L chromium standard and use solution 0mL, 1.0mL, 2.0mL, 3.0mL, 4.0mL, be placed in 100mL volumetric flask, with volume ratio be 1 part of nitric acid: the salpeter solution of 99 parts of distilled water is diluted to scale, shake up, be mixed with the standard series sample of 0ug/L, 10ug/L, 20ug/L, 30ug/L, 40ug/L;

2) sample is underground water, draws 20uL sample and standard series sample measure with 20ul microsyringe;

3) use Agilent atomic absorption spectrophotometer (AAS) 3511 graphite furnace systemic effect experimental apparatuss, regulate instrument to optimum condition, after instrument stabilizer, test instrument condition of work:

Wavelength: 357.8nm;

Lamp current: 2.0mA;

Slit: 0.2nm;

4) open argon gas source of the gas and water source, argon pressure is adjusted to 0.3MPa;

5) parameters setting in experiment:

Drying stage: 90～100 DEG C of 10～15 minutes retention times 15～20 minute heating-up time of temperature

The ashing stage: 680～720 DEG C of 15～20 minutes retention times 15～20 minute heating-up time of temperature

Atomized stage: 2800～3000 DEG C of 5～6 minutes retention times 1～2 minute heating-up time of temperature

Wash phase: 2900～3100 DEG C of 3～4 minutes retention times 2～3 minute heating-up time of temperature

6), under the best operating condition of instrument, in wavelength 357.8nm place, with blank zeroing, survey its absorbance; Taking measure absorbance as ordinate, corresponding chromium content is horizontal ordinate, drawing standard curve; Press the equal instrument condition of typical curve, with blank zeroing, measure the absorbance of sample, try to achieve the corresponding chromium content of sample, the ug/l of unit from typical curve.

Following examples are implemented under taking technical solution of the present invention as prerequisite, provided detailed embodiment and concrete operating process, but protection scope of the present invention are not limited to following embodiment.In following embodiment, method therefor is conventional method if no special instructions.

[embodiment 1] application the method for the invention is measured the underground water of 30 well heads, replicate determination 3 times, and concrete steps are as follows:

1) draw 1mg/L chromium standard and use solution 0mL, 1.0mL, 2.0mL, 3.0mL, 4.0mL, be placed in 100mL volumetric flask, with volume ratio be 1 part of nitric acid: the salpeter solution of 99 parts of distilled water is diluted to scale, shake up, be mixed with the standard series sample of 0ug/L, 10ug/L, 20ug/L, 30ug/L, 40ug/L;

2) measure with 20ul microsyringe absorption 20uL sample and standard series sample;

3) use Agilent atomic absorption spectrophotometer (AAS) 3511 graphite furnace systemic effect experimental apparatuss, regulate instrument to optimum condition, after instrument stabilizer, test instrument condition of work:

Wavelength: 357.8nm;

Lamp current: 2.0mA;

Slit: 0.2nm;

4) open argon gas source of the gas and water source, argon pressure is adjusted to 0.3MPa;

5) parameters setting in experiment:

Drying stage: 90 DEG C of 10 minutes retention times 15 minute heating-up time of temperature

The ashing stage: 700 DEG C of 15 minutes retention times 15 minute heating-up time of temperature

Atomized stage: 2900 DEG C of 5 minutes retention times 1 minute heating-up time of temperature

Wash phase: 3000 DEG C of 3 minutes retention times 2 minute heating-up time of temperature

6), under the best operating condition of instrument, in wavelength 357.8nm place, with blank zeroing, survey its absorbance; Taking measure absorbance as ordinate, corresponding chromium content is horizontal ordinate, drawing standard curve; Press the equal instrument condition of typical curve, with blank zeroing, measure the absorbance of sample, try to achieve the corresponding chromium content of sample, the ug/l of unit from typical curve.

Precision test result is as follows:

The relative standard deviation of above measuring result: 4.0%～10.4%.

Recovery test result is as follows:

Numbering	Add scalar (μ g/l)	Measured value-background values (μ g/l)	Recovery %
				1	0.50	0.470	94
2	0.50	0.530	106
				3	0.50	0.565	113
4	0.50	0.546	109
				5	1.0	0.960	96
6	1.0	1.012	101
				7	1.0	0.970	97
8	1.0	1.042	104

Above chromium recovery test recovery of standard addition: 94%～113%.

[embodiment 2] application the method for the invention is measured the underground water of 30 well heads, replicate determination 3 times, and concrete steps are as follows:

1) draw 1mg/L chromium standard and use solution 0mL, 1.0mL, 2.0mL, 3.0mL, 4.0mL, be placed in 100mL volumetric flask, with volume ratio be 1 part of nitric acid: the salpeter solution of 99 parts of distilled water is diluted to scale, shake up, be mixed with the standard series sample of 0ug/L, 10ug/L, 20ug/L, 30ug/L, 40ug/L;

2) measure with 20ul microsyringe absorption 20uL sample and standard series sample;

3) use Agilent atomic absorption spectrophotometer (AAS) 3511 graphite furnace systemic effect experimental apparatuss, regulate instrument to optimum condition, after instrument stabilizer, test instrument condition of work:

Wavelength: 357.8nm;

Lamp current: 2.0mA;

Slit: 0.2nm;

4) open argon gas source of the gas and water source, argon pressure is adjusted to 0.3MPa;

5) parameters setting in experiment:

Drying stage: 100 DEG C of 15 minutes retention times 20 minute heating-up time of temperature

The ashing stage: 720 DEG C of 20 minutes retention times 20 minute heating-up time of temperature

Atomized stage: 3000 DEG C of 6 minutes retention times 2 minute heating-up time of temperature

Wash phase: 3100 DEG C of 4 minutes retention times 3 minute heating-up time of temperature

6), under the best operating condition of instrument, in wavelength 357.8nm place, with blank zeroing, survey its absorbance; Taking measure absorbance as ordinate, corresponding chromium content is horizontal ordinate, drawing standard curve; Press the equal instrument condition of typical curve, with blank zeroing, measure the absorbance of sample, try to achieve the corresponding chromium content of sample, the ug/l of unit from typical curve.

Precision test result is as follows:

The relative standard deviation of above measuring result: 4.1%～10.6%.

Recovery test result is as follows:

Numbering	Add scalar (μ g/l)	Measured value-background values (μ g/l)	Recovery %
				1	0.50	0.537	107
2	0.50	0.562	112
				3	0.50	0.465	93
4	0.50	0.545	109
				5	1.0	0.984	98
6	1.0	1.012	101
				7	1.0	1.056	106
8	1.0	0.963	96

Above chromium recovery test recovery of standard addition: 93%～112%.

Claims (1)

1. an assay method for total chromium in underground water, is characterized in that, comprises the steps:

1) draw 1mg/L chromium standard and use solution 0mL, 1.0mL, 2.0mL, 3.0mL, 4.0mL, be placed in 100mL volumetric flask, with volume ratio be 1 part of nitric acid: the salpeter solution of 99 parts of distilled water is diluted to scale, shake up, be mixed with the standard series sample of 0ug/L, 10ug/L, 20ug/L, 30ug/L, 40ug/L;

2) sample is underground water, draws 20uL sample and standard series sample measure with 20ul microsyringe;

3) use Agilent atomic absorption spectrophotometer (AAS) 3511 graphite furnace systemic effect experimental apparatuss, regulate instrument to optimum condition, after instrument stabilizer, test instrument condition of work:

Wavelength: 357.8nm;

Lamp current: 2.0mA;

Slit: 0.2nm;

4) open argon gas source of the gas and water source, argon pressure is adjusted to 0.3MPa;

5) parameters setting in experiment:

Drying stage: 90～100 DEG C of 10～15 minutes retention times 15～20 minute heating-up time of temperature

The ashing stage: 680～720 DEG C of 15～20 minutes retention times 15～20 minute heating-up time of temperature

Atomized stage: 2800～3000 DEG C of 5～6 minutes retention times 1～2 minute heating-up time of temperature

Wash phase: 2900～3100 DEG C of 3～4 minutes retention times 2～3 minute heating-up time of temperature

6), under the best operating condition of instrument, in wavelength 357.8nm place, with blank zeroing, survey its absorbance; Taking measure absorbance as ordinate, corresponding chromium content is horizontal ordinate, drawing standard curve; Press the equal instrument condition of typical curve, with blank zeroing, measure the absorbance of sample, try to achieve the corresponding chromium content of sample, the ug/l of unit from typical curve.