CN106323930A

CN106323930A - Method for determining content of Cr in K2Cr2O7 for fireworks and firecrackers

Info

Publication number: CN106323930A
Application number: CN201610777393.6A
Authority: CN
Inventors: 吴俊逸
Original assignee: Individual
Current assignee: Individual
Priority date: 2016-08-31
Filing date: 2016-08-31
Publication date: 2017-01-11

Abstract

The invention discloses a method for determining the content of Cr in K2Cr2O7 for fireworks and firecrackers. The method comprises the following steps: 1) drawing a calibration curve: 1.1) preparing multiple Cr working solutions with different concentrations; 1.2) acquiring spectra and drawing the calibration curve; 2) rapidly determining the content of Cr in K2Cr2O7: 2.1) preparing a specimen solution; 2.2) analyzing the specimen solution; 2.3) calculating the content of Cr in a specimen. According to the method, a matrix effect between elements in the specimen can be eliminated or basically eliminated by optimizing specimen dissolving conditions and parameter conditions of the X-ray fluorescence spectrophotometer, and the content of Cr in K2Cr2O7 for fireworks and firecrackers can be determined accurately and directly by an energy dispersion type X-ray fluorescence spectrophotometer. The method is simple to operate, short in detection cycle, low in labor intensity, good in accuracy and high in precision and has low requirements for an operator.

Description

A kind of measure the method for chromium content in fireworks and firecrackers potassium dichromate

Technical field

The present invention relates to a kind of method of chromium content in potassium dichromate, especially a kind of mensuration fireworks and firecrackers potassium dichromate The method of middle chromium content, belongs to analysis and testing technology field.

Background technology

In prior art, in fireworks and firecrackers potassium dichromate, the detection method of chromium content is based on traditional chemical analysis side Method, the most conventional method standard is " mensuration the 15th part of fireworks and firecrackers chemical raw material key index: potassium dichromate " (SN/T3056.15-2011).The ultimate principle of this standard method: test portion after pretreatment, with hot water dissolving and filter, filtrate Respectively with bichromate content in iodometric determination test portion after eliminating interfering ion, filtering residue sodium hydroxide and EDTA and dissolving.

Method described in this standard has the disadvantage that (1) detection cycle is longer, and general those of skill in the art need 2 works Make day just to complete one-time detection.It addition, be easy in concrete process of the test because testing crew skilled operation degree draws not Enter to cause the uncertainty of measuring result error.(2) complex operation step, after sample dehydrated alcohol and acetone repeatedly wash, Successively experience with hot water dissolving, filter, wash, sucking filtration, shift, precipitate, precipitate enrichment, filtering residue dissolves, wash, shift, constant volume With steps such as titration.(3) method requires height to experimenter, and in operating procedure, many places relate to washing, shift, precipitate, are enriched with, drip Fixed etc. be readily incorporated probabilistic operating procedure, each test operation personnel must significant care and careful, hold the most very much It is easily introduced artificial uncertainty.

The method that energy dispersion type Xray fluorescence spectrometer is developed at present is used for the lossless qualitative analysis of sample.Pin Detecting solid sample sxemiquantitative and quantitative elemental, most samples use nondestructive determination, powder pressing method and fusion method Directly measure (such as: " the mensuration X-ray fluorescence spectroscopy of bullion content " (GB/T 18043-2008) uses lossless inspection Survey method, " aluminium oxide chemical analysis method and method for measuring physical properties the 30th partial x-ray fluorescence spectrum method for measuring element contain Amount " (GB/T6609.30 2009) use fusion method, and " EDXRF method directly measures W-Fe-Ni-Co alloy compound group Point " (" nuclear electronics and Detection Techniques " 05 phase in 2007) use pressed disc method, " regulated substance lead in electronic and electrical equipment, The rapid screening X-ray fluorescence spectroscopy of hydrargyrum, chromium, cadmium and bromine " (GB/Z 21277-2007) use pressed disc method or melted Method).Using energy dispersion type Xray fluorescence spectrometer to carry out assay with simple to operate, the detection cycle is short, and accuracy Good, precision height is widely used in the quick analysis of inorganic elements.

The potassium dichromate quality discrepancy used due to different types of fireworks and firecrackers goods is very big, the chemical composition of its impurity The most extremely complex.The matrix effect that there is complexity in potassium dichromate raw material between element (includes absorption-enhancement effect between element With physical-chemical effect), it is impossible to utilize energy dispersion type X-ray fluorescence spectroscopy (EDXRF) directly use powder pressing method and Fusion method measures the solid powder sample that matrix background is complicated and changeable.The most also there are no energy dispersion type XRF The open source literature report of chromium content in spectrographic method detection fireworks and firecrackers potassium dichromate.

Summary of the invention

The present invention provides a kind of and measures the method for chromium content in fireworks and firecrackers potassium dichromate, by optimizing sample dissolution bar Part and each Parameter Conditions of Xray fluorescence spectrometer device, eliminate or substantially eliminate the matrix effect between each element in sample, directly The chromium content in fireworks and firecrackers potassium dichromate, method operation letter is gone out with energy dispersion type X-ray fluorescence spectroscopy Accurate Determining Single, the detection cycle is short, and labor intensity is low and less demanding to operator, and accuracy is good, and precision is high.

The technical solution used in the present invention is:

A kind of measure the method for chromium content in fireworks and firecrackers potassium dichromate, comprise the steps:

1) calibration curve is drawn:

1.1) preparation chromium working solution: weigh the reference material containing chromium element, adds water and nitric acid dissolves, and is transferred to hold Measuring bottle is also settled to certain volume, obtains certain density chromium solution, then pipettes the chromium solution of many parts of different volumes to capacity Bottle constant volume, obtain the chromium working solution of different quality concentration；Control the mass concentration of chromium in chromium working solution be 0.03g/L～ 0.58g/L；

1.2) analyze and draw calibration curve: with energy dispersion type Xray fluorescence spectrometer as detecting instrument, with 0.8g be Calibration curve suppose sample size, use X fluorescence spectrum quantitative analysis intensity correction mathmetic correction set up analysis method, Aperture is the X-ray light pipe collimator of 8.8mm～14mm and can filter the filter that energy is less than the X-ray of 5.968KeV, if Putting voltage is 8kV～16kV, and analysis time is 30s～80s, and energy range is 0～40keV, during counting rate is, gaseous environment For air, electric current is that matrix effect is not for consider automatically；

By step 1.1) in chromium working solution in the mass concentration of Cr be converted into the mass percent concentration of Cr, the most one by one Sample introduction, records the fluorescence intensity of the Cr of each sample introduction, and the mass percent concentration of Cr in chromium working solution is as abscissa, with correspondence Fluorescence intensity be vertical coordinate, make calibration curve；

Wherein, by following formula the mass concentration of Cr in chromium working solution is converted into the mass percent concentration of Cr:

C r % = \frac{c \times 0.5}{0.8} \times 100 %

Wherein, Cr% represents the mass percent concentration of Cr in chromium working solution, and unit is %；C represents Cr in chromium working solution Mass concentration, unit is g/L；0.5 represents the volume supposing sample size constant volume, and unit is L；0.8 represents that calibration curve supposes Sample size, unit is g；

2) the chromium content in potassium dichromate is quickly measured:

2.1) preparation test liquid: with fireworks and firecrackers potassium dichromate raw material as sample, during preparation test liquid, weighs sample also It is accurate to 0.1mg, is placed in beaker, add 100mL～150mL water, beaker is placed on electric furnace heating 10min～15min, takes advantage of Heat filter paper filtering, filtrate is filtered to volumetric flask, is added a certain amount of nitric acid, add after the solution in volumetric flask is cooled to room temperature Water is settled to scale；On the basis of 0.7g～0.9g sample constant volume to 500mL, calculate sample during constant volume answer the concrete volume of constant volume；

2.2) detection test liquid: by step 1.2) testing conditions, test liquid is loaded specimen cup, sample liquid thickness >= 15mm, on grapher display fluorescence intensity, then according to step 1.2) in draw calibration curve read corresponding Cr mass percent concentration value ω₀；

2.3) content of chromium in calculating sample:

The mass percent concentration ω of simple substance chromium in calculating sample as follows:

ω = ω_{0} \times \frac{0.8}{m} \times \frac{V}{500}

Wherein, ω represents the mass percent concentration of simple substance chromium in sample, and unit is %；ω₀Represent according to calibration curve The Cr mass percent concentration value read, unit is %；0.8 represents the sample size that calibration curve supposes, unit is g；M represents examination The quality of the actual weighing of sample, unit is g；V is the volume of actual constant volume after representing sample dissolution, and unit is mL, and 500 represent supposition sample The volume of this amount constant volume, unit is mL.

Step 1.1) in, in order to ensure accuracy and the precision of test result, in chromium working solution, the mass concentration of Cr is true It is set to 0.03g/L～0.58g/L, is on the basis of the matrix effect considering energy dispersion type Xray fluorescence spectrometer, and Finally determine after having carried out substantial amounts of test.

Step 1.1) in, the chromium solution pipetting 5～15 parts of different volumes prepares chromium working solution.

It is preferably, step 1.1) in, the reference material containing chromium element is potassium dichromate.

It is preferably, step 1.1) in, described nitric acid volume is 10mL～30mL, HNO in nitric acid₃Mass percent concentration is 10%～30%.

It is preferably, step 1.2) in, the X-ray light pipe collimator using aperture to be 8.8mm during detection, use aluminum filter, Arranging voltage is 12kV, and analysis time is 50s, and energy range is 0～20keV.

It is preferably, step 2.1) in, HNO in described nitric acid₃Mass percent concentration is 10%～30%.

It is preferably, step 2.2) in, sample liquid thickness is 15mm～30mm.

Step 2.1) in, in order to ensure the accuracy of test result, considering energy dispersion type Xray fluorescence spectrometer Matrix effect on the basis of, and carried out substantial amounts of test, the actual test portion finally determined is settled to 0.7g～0.9g 500mL is optimal.

In order to ensure accuracy and the precision of test result, in test, selected 0.8g is the sample that calibration curve supposes Amount, is on the basis of the matrix effect considering energy dispersion type Xray fluorescence spectrometer, and it is true to have carried out substantial amounts of test Fixed.

The ultimate principle of the inventive method: first, for the fireworks and firecrackers feature of firework medicament chemical composition, sets up specially The mathematical model of door, global optimization can directly affect each factor of measurement result, including: dissolve the solvent kind of test portion Class, chemical composition and volume number, test portion dissolution conditions, test solution constant volume, for setting up the matrix effect mathematics of analysis method Correction method type, for make calibration curve test portion suppose sample size, series standard solution matrix composition, concentration range and The interval of standard solution point value and quantity, the actual sample weighting amount of test portion and the matrix effect phase of energy dispersion type X fluorescence spectrum instrument The work in everies such as interaction form, voltage, electric current, the selection of filter, analysis time, counting rate, gaseous environment, energy range The thickness etc. of test solution in parameter and specimen cup.Consideration based on solvent compositing characteristic, selects water to dissolve test portion as solvent, can be by Cr element and other separation of foreign elements water-fast such as Cu, Fe, Ti, Al, Mg in test portion, and be not introduced into except H and O element Other outer interference elements；Secondly, global optimization test portion dissolution conditions, test solution constant volume, for setting up the base of analysis method Bulk effect mathmetic correction type, the test portion of making calibration curve suppose sample size, the matrix composition of series standard solution, concentration Scope and the interval of standard solution point value and quantity, the actual sample weighting amount of test portion and the matrix of energy dispersion type X fluorescence spectrum instrument Effect interaction type, voltage, electric current, the selection of filter, analysis time, counting rate, gaseous environment, energy range etc. are every In running parameter and specimen cup, in the work in every parameter such as thickness of test solution and specimen cup, the thickness etc. of test solution directly affects mensuration Each factor of result, by the supposition sample size of global design test portion, the sample size of actual sample, Xray fluorescence spectrometer Every test parameter, for making matrix composition and the key such as concentration span of control thereof of the series standard solution of calibration trace Testing factors, sets up and is specifically designed for the calibration trace of Cr element determination in fireworks and firecrackers potassium dichromate, in this test condition, Owing in sample test solution, the impurity element concentration such as K, Cl, Na is extremely low, it is insensitive that the element such as H and O belongs to Xray fluorescence spectrometer Light element, and the matrix effect of Cr element is negligible in calibration trace standard point interval concentration range, thus realizes target To the matrix effect controlled in test solution between each element；Finally, can be according to the difference of all kinds fireworks and firecrackers firework medicament sample The opposite sex determines whether to adjust sample size, carries out the quantitative analysis of Cr element based on this calibration trace.

The present invention utilizes solwution method eliminate or substantially eliminate matrix effect, thus can directly use energy dispersion type X-ray Fluorescent spectrometry Accurate Determining goes out the chromium content in fireworks and firecrackers potassium dichromate；

Solwution method is used to eliminate or substantially eliminate matrix effect and advantage is in particular in:

(1) liquor sample eliminates the intrinsic inhomogeneities of solid sample and physical-chemical effect, and the analysis obtained is tied Fruit more can represent whole analysis sample；

(2) composition of Macrodilution based on solvent, sample and standard specimen is close to the composition of solvent, and solvent is mainly by light unit Element composition, absorption-enhancement effect becomes the least, and matrix effect substantially can not consider；It is additionally, since X-ray to penetrate deeply Degree is relatively deep, and fluorescent radiation absorbs less, so higher absolute sensitivity can be obtained；

(3) if solution made by the sample that standard specimen is difficult to obtain, calibration curve can use standard reagent to synthesize, and estimates the back of the body The blank sample of the factors such as scape is readily made；

(4) sample constant volume after water-soluble is imitated to certain volume, the matrix that in test liquid, Cr element is produced by K, H, O, N element Should be the least, it is negligible.

Use and have the beneficial effects that produced by technique scheme:

1, the present invention utilizes solwution method eliminate or substantially eliminate matrix effect, directly with energy dispersion type XRF light Spectrometry Accurate Determining goes out the chromium content in fireworks and firecrackers potassium dichromate, and method is simple to operate, and labor intensity is low and to operator Member is less demanding.

2, the present invention is after establishing calibration curve, whole mensuration process only include sample weighing, dissolve, shift constant volume, 4 easy steps such as examination with computer, total time-consuming less than 2h, labor intensity is low and less demanding to operator.

3, using the method for the present invention to detect, accuracy is good, and precision is high.

Accompanying drawing explanation

The present invention is further detailed explanation with detailed description of the invention below in conjunction with the accompanying drawings.

Fig. 1 is the calibration curve of the mass percent concentration-fluorescence intensity of the Cr that inventive embodiments 1 obtains；The most horizontal seat Being designated as the mass percent concentration of Cr in each chromium working solution, unit is %；Vertical coordinate is and the mass percent concentration of above-mentioned Cr Corresponding fluorescence intensity, unit is cps/mA.

Detailed description of the invention

With specific embodiment, the invention will be further described below, but the invention is not limited in following embodiment.

Embodiment 1:

1) calibration curve is made

1.1) preparation chromium working solution (requiring that in the chromium working solution of gained, the mass concentration of Cr is 0.03g/L～0.58g/L):

Concrete compound method is with reference to as follows:

Accurately weigh 2.0g potassium dichromate reference material (being accurate to 0.1mg), be placed in 300mL beaker, add 100mL～ 150mL water, is placed in beaker on electric furnace heating 10min～15min, is transferred to 500mL volumetric flask after solution is cooled to room temperature, Addition 10mL～30mL nitric acid adds water and is settled to scale, obtains chromium solution；Wherein, HNO in nitric acid₃Mass percent be 10% ～30%.

Prepare 10 parts of chromium working solutions: pipette respectively the chromium solution 5mL after above-mentioned constant volume, 10mL, 15mL, 20mL, 30mL, 40mL, 50mL, 60mL, 70mL and 80mL, in one group of 100mL volumetric flask, are diluted with water to scale, mixing, respectively numbered work 1, the chromium working solution of work 2, work 3, work 4, work 5, work 6, work 7, work 8, work 9 and work 10, in 10 parts of chromium working solutions, Cr concentration is shown in Table 1；

1.2) detect and draw calibration curve:

2a) with energy dispersion type Xray fluorescence spectrometer (power & light company of the U.S. (Thermo Electron Corporation) producing, model is QUANT ' X EDXRY Analyzer) it is detecting instrument, suppose with 0.8g for calibration curve Sample size, by step 1) mass concentration of Cr is become the percent mass of Cr by following formula scales in many parts of chromium working solutions preparing Specific concentration, the results are shown in Table 1；

C r % = \frac{c \times 0.5}{0.8} \times 100 %

Wherein, Cr% represents the mass percent concentration of Cr in chromium working solution, and unit is %；C represents Cr in chromium working solution Mass concentration, unit is g/L；0.5 represents the volume supposing sample size constant volume, and unit is L；0.8 represents that calibration curve supposes Sample size, unit is g.

Cr concentration and the fluorescence intensity of correspondence in table 1 chromium working solution

2b) at energy dispersion type Xray fluorescence spectrometer, 8.8mm X-ray light pipe collimator is installed, it is ensured that detector Temperature prepares to set up assay method after being down to 190K；Analysis method is set up by the intensity correction method of X fluorescence spectrum quantitative analysis, Using aluminum filter, arranging voltage is 12kV, and analysis time is 50s, and energy range is 0～20keV, during counting rate is, and Ring Border is air, and electric current is that matrix effect is not for consider automatically.The each method ginseng of described energy dispersion type Xray fluorescence spectrometer Number is as shown in table 2；

Table 2 energy dispersion type Xray fluorescence spectrometer parameter

Filter

Voltage

Electric current

Analysis time

Counting rate

Gaseous environment

Matrix effect

Energy range

Aluminum

12kv

Automatically

50s

In

Air

Do not consider

0～20kev

2c) start sample introduction one by one with the Cr mass percent concentration after conversion in table 1 for initial data and adopt spectrum, each sample introduction Sample liquid thickness be 15mm, record the fluorescence intensity of each sample introduction, the mass percent concentration of Cr in each chromium working solution is as horizontal stroke Coordinate, with corresponding fluorescence intensity as vertical coordinate, makes calibration curve, as shown in Figure 1.

Embodiment 2: use the method for the invention that fireworks and firecrackers potassium dichromate reference material or chromium standard solution are entered The controlled trial that row measures

Test with fireworks and firecrackers potassium dichromate reference material listed in table 3 and chromium standard solution, wherein weigh chromium The chromium nominal content of acid potassium reference material and chromium standard solution is as shown in table 3；When using the method for the invention to measure, weight Neutral potassium chromate reference material carries out chrome determination after preparing test liquid as follows again.

1) preparation test liquid:

Prepare test liquid with the reference material of numbering 1 for sample, weigh 3 parts of 0.7g～0.9g sample, be accurate to when weighing 0.1mg, the 1st part of sample is placed in 300mL beaker, adds 100mL water, is placed on electric furnace heating 10min, by filter paper mistake while hot Filter to 500mL volumetric flask, repeatedly rinse repeatedly with water, after filtrate is cooled to room temperature, add 5mL～10mL concentration be 10%～ The nitric acid of 30%, then be settled to 500mL with water and obtain the 1st part of test liquid；Repeat said method, obtain the 3 of No. 1 reference material Part test liquid；

2) mensuration of chromium in reference material:

By embodiment 1 step 2b) testing conditions, by 3 parts of test liquid sample introductions one by one of the reference material of numbering 1, sample introduction Sample liquid thickness be 15mm, the fluorescence intensity of display on grapher, the calibration determined according to embodiment 1 with this fluorescence intensity is bent Line reads corresponding Cr mass percent concentration value；

The mass percent concentration of chromium in the reference material of calculating numbering 1 the most as follows:

ω = ω_{0} \times \frac{0.8}{m} \times \frac{V}{500}

Wherein, ω represents the mass percent concentration of chromium in sample, and unit is %；ω₀Represent and read according to calibration curve Cr mass percent concentration value, unit is %；M represents the quality of the actual weighing of sample, and unit is g, typically weigh 0.7g～ 0.9g；V represents the volume of constant volume after sample dissolution, and unit is mL.

Take the chromium content of the reference material that meansigma methods is numbering 1 of wherein three result of calculation values, result as indicated at 3, and Calculate its response rate, the results are shown in Table 3.

By above-mentioned steps 1) and step 2) method, the test liquid of reference material of preparation numbering 2 and 3, calculates it respectively Chromium content and the response rate, the results are shown in Table 3.

The most directly carry out the above-mentioned 2nd as the chromium standard solution in table 3) step, each chromium titer do equally 3 parts parallel Sample, takes the meansigma methods chromium content as chromium standard solution of three result of calculation values, and result as indicated at 3, and calculates its response rate, The results are shown in Table 3.

Table 3 controlled trial data

As shown in Table 3, the method for the invention is to different main content fireworks and firecrackers potassium dichromate reference materials and series In chromium standard solution, the chromium element determination of different content has good accuracy.

Embodiment 3: use the method for the invention to the testing result of the potassium dichromate reference material of different main content Precision test

The present embodiment tries with the fireworks and firecrackers potassium dichromate reference material of numbered 4,5 and 6 in table 3 for sample Test.

1) preparation test liquid:

Prepare test liquid with the reference material of numbering 1 for sample, weigh 4 parts of 0.7g～0.9g sample, be accurate to when weighing 0.1mg, the 1st part of sample is placed in 300mL beaker, adds 100mL water, is placed on electric furnace heating 10min, by filter paper mistake while hot Filter to 500mL volumetric flask, repeatedly rinse repeatedly with water, after filtrate is cooled to room temperature, add 5mL～10mL concentration be 10%～ The nitric acid of 30%, then be settled to 500mL with water and obtain the 1st part of test liquid；Repeat said method, obtain 4 parts of No. 4 reference materials Test liquid.

2) mensuration of chromium content in reference material:

By embodiment 1 step 2b) testing conditions, by 4 parts of test liquid sample introductions one by one of the reference material of numbering 1, every part Test liquid measures 11 times, and each sample introduction makes sample liquid thickness be 15mm, and on grapher, the fluorescence intensity of the Cr of display, glimmering with this The calibration curve that light intensity determines according to embodiment 1 reads corresponding K mass percent concentration value；

Calculating the mass percent concentration of chromium in the reference material of numbering 1 the most as follows, result is as shown in table 5.

ω = ω_{0} \times \frac{0.8}{m} \times \frac{V}{500}

Wherein, ω represents the mass percent concentration of chromium in sample, and unit is %；ω₀Represent and read according to calibration curve Cr mass percent concentration value, unit is %；0.8 represents the sample size that calibration curve supposes, unit is g；M represents that sample is real The quality that border weighs, unit is g, typically weighs 0.7g～0.9g；V represents the volume of constant volume after sample dissolution, and unit is mL； 500 represent the volume supposing sample size constant volume, and unit is mL.

By above-mentioned steps 1) and step 2) method, the test liquid of reference material of preparation numbering 5 and 6 respectively, and calculating Their chromium content, the results are shown in Table 4.

Table 4 uses the precision test data that the inventive method is carried out

As shown in Table 4, chromium element determination in different main content potassium dichromate reference materials is had by the method for the invention Good precision, maximum allowable difference is 0.4%.

Embodiment 4

The mensuration of chromium content in actual fireworks and firecrackers potassium dichromate

1, for the fireworks and firecrackers sample of detection:

1#: sample combines fireworks display potassium dichromate raw materials from Pubei County, Guangxi fireworks station-service in 36 produced.

2#: sample produces the smog class former material of fireworks potassium dichromate from being used for of producing of Lingshan County, Guangxi fireworks factory Material.

2, use the method for the invention that above-mentioned fireworks sample is detected:

Using the calibration curve that embodiment 1 determines, fireworks sample detection step is specific as follows:

2.1) preparation test liquid:

Weigh 1# potassium dichromate raw material sample 0.7g～3 parts of 0.9g sample respectively, when weighing, be accurate to 0.1mg, 3 parts of examinations Sample is placed in 300mL beaker, is separately added into 100mL, 120mL, 150mL water, be placed on electric furnace heat respectively 10min, 13min, 15min, be filtered hot to 500mL volumetric flask with filter paper, repeatedly rinses repeatedly with water, after filtrate is cooled to room temperature, (in this step, it is 30%, 20% and that 3 parts of samples are respectively adopted weight/mass percentage composition to be separately added into 5mL, 8mL, 10mL nitric acid The nitric acid of 10%), then be settled to 500mL with water and obtain the 1st part of test liquid；Repeat said method, obtain the 3 of No. 1 reference material Part test liquid.

2) mensuration of chromium content in reference material:

By embodiment 1 step 2b) testing conditions, by 3 parts of test liquid sample introductions one by one of 1# firework medicament sample, load sample The sample path length of product cup is 15mm, and grapher shows the fluorescence intensity of Cr, determines according to embodiment 1 with this fluorescence intensity Calibration curve reads corresponding Cr mass percent concentration value；

Calculating the mass percent concentration of chromium in 1# firework medicament sample the most as follows, result is as shown in table 5.

ω = ω_{0} \times \frac{0.8}{m} \times \frac{V}{500}

Wherein, ω represents the mass percent concentration of chromium in sample, and unit is %；ω₀Represent and read according to calibration curve Cr mass percent concentration value, unit is %；0.8 represents the sample size that calibration curve supposes, unit is g；M represents that sample is real The quality that border weighs, unit is g；V represents the volume of constant volume after sample dissolution, and unit is mL；500 represent supposition sample size constant volume Volume, unit is mL.

By the compound method of the test liquid of above-mentioned 1# potassium dichromate raw material sample, prepare 2# potassium dichromate raw material sample Test liquid, and calculate its chromium content, the results are shown in Table 5.

While measuring above-mentioned firework medicament potassium dichromate raw material sample by this method, it is also adopted by existing traditional Credit analysis method (" fireworks and firecrackers mensuration the 15th part of chemical raw material key index: potassium dichromate " (SN/ T3056.15-2011)) being detected above-mentioned sample, result is as described in Table 5.

The determination data table of chromium content in table 5 actual fireworks and firecrackers potassium dichromate

Claims

1. one kind measures the method for chromium content in fireworks and firecrackers potassium dichromate, it is characterised in that it comprises the steps:

1) calibration curve is drawn:

1.1) preparation chromium working solution: weigh the reference material containing chromium element, adds water and dissolves, be transferred to volumetric flask, then add Enter appropriate nitric acid, be settled to certain volume with water, obtain certain density chromium solution, pipette many parts of different volumes the most respectively Chromium solution, to multiple volumetric flasks constant volume, obtains the chromium working solution of different quality concentration；Make the mass concentration of chromium in chromium working solution For 0.03g/L～0.58g/L；

1.2) detect and draw calibration curve: with energy dispersion type Xray fluorescence spectrometer as detecting instrument, with 0.8g for calibration The sample size that curve supposes, the X-ray light pipe collimator using aperture to be 8.8mm～14mm, it is possible to filter energy and be less than The filter of the X-ray of 5.968KeV, arranging voltage is 8kV～16kV, and analysis time is 30s～80s, energy range be 0～ 40keV, and use the intensity correction method of X fluorescence spectrum quantitative analysis to set up analysis method；

By step 1.1) in chromium working solution in the mass concentration of Cr be converted into the mass percent concentration of Cr, enter the most one by one Sample, records the fluorescence intensity of the Cr of each sample introduction, and the mass percent concentration of Cr in chromium working solution is as abscissa, with correspondence Fluorescence intensity is vertical coordinate, makes calibration curve；

C r % = \frac{c \times 0.5}{0.8} \times 100 %

Wherein, Cr% represents the mass percent concentration of Cr in chromium working solution, and unit is %；C represents the matter of Cr in chromium working solution Amount concentration, unit is g/L；0.5 represents the volume supposing sample size constant volume, and unit is L；0.8 represents the sample that calibration curve supposes This amount, unit is g；

2) the chromium content in potassium dichromate is quickly measured:

2.1) preparation test liquid: with fireworks and firecrackers potassium dichromate as sample, during preparation test liquid, weighs sample and is accurate to 0.1mg, is placed in beaker, adds 100mL～150mL water, beaker is placed on electric furnace heating 10min～15min, while hot with filter Paper filters, and filtrate is filtered to volumetric flask, adds a certain amount of nitric acid, and add water after the solution in volumetric flask is cooled to room temperature constant volume To scale；On the basis of 0.7g～0.9g sample constant volume to 500mL, calculate sample during constant volume answer the concrete volume of constant volume；By 5mL ～10mL amount adds nitric acid, the mass percent concentration of nitric acid is 10%～30%；

2.2) detection test liquid: by step 1.2) testing conditions, test liquid is loaded specimen cup, sample liquid thickness >=15mm, note The fluorescence intensity of display on record instrument, then according to step 1.2) in the calibration curve drawn read corresponding Cr mass hundred Proportion by subtraction concentration value ω₀；

2.3) content of chromium in calculating sample:

ω = ω_{0} \times \frac{0.8}{m} \times \frac{V}{500}

Wherein, ω represents the mass percent concentration of simple substance chromium in sample, and unit is %；ω₀Represent according to calibration curve reading Cr mass percent concentration value, unit is %；0.8 represents the sample size that calibration curve supposes, unit is g；M represents that sample is actual The quality weighed, unit is g；V represents the volume of constant volume after sample dissolution, and unit is mL, and 500 represent and suppose sample size constant volumes Volume, unit is mL.

The most according to claim 1 a kind of measure the method for chromium content in fireworks and firecrackers potassium dichromate, it is characterised in that Described step 1.1) in, the chromium solution pipetting 5～15 parts of different volumes prepares chromium working solution.

The most according to claim 1 a kind of measure the method for chromium content in fireworks and firecrackers potassium dichromate, it is characterised in that Described step 1.1) in, the reference material containing chromium element is potassium dichromate, and the volume of described nitric acid is 10mL～30mL, in nitric acid HNO₃Mass percent concentration is 10%～30%.

The most according to claim 1 a kind of measure the method for chromium content in fireworks and firecrackers potassium dichromate, it is characterised in that Described step 1.2) in, the X-ray light pipe collimator using aperture to be 8.8mm～14mm during detection, use aluminum filter, electricity is set Pressure is 12kV, and analysis time is 50s, and energy range is 0～20keV.

The most according to claim 1 a kind of measure the method for chromium content in fireworks and firecrackers potassium dichromate, it is characterised in that Described step 2.1) in, the quality weighing sample is 0.7g～0.9g.

The most according to claim 1 a kind of measure the method for chromium content in fireworks and firecrackers potassium dichromate, it is characterised in that Described step 2.1) in, HNO in described nitric acid₃Mass percent concentration is 10%～30%.

The most according to claim 1 a kind of measure the method for chromium content in fireworks and firecrackers potassium dichromate, it is characterised in that Described step 2.2) in, sample liquid thickness is 15mm～30mm.