CN1400461A - Method for determining content of Pt, Eu and Ce elements in reformed catalyst - Google Patents

Method for determining content of Pt, Eu and Ce elements in reformed catalyst Download PDF

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CN1400461A
CN1400461A CN 01123762 CN01123762A CN1400461A CN 1400461 A CN1400461 A CN 1400461A CN 01123762 CN01123762 CN 01123762 CN 01123762 A CN01123762 A CN 01123762A CN 1400461 A CN1400461 A CN 1400461A
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platinum
europium
content
cerium
elements
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CN1156690C (en
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高萍
顾若晶
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Sinopec Research Institute of Petroleum Processing
China Petroleum and Chemical Corp
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Sinopec Research Institute of Petroleum Processing
China Petroleum and Chemical Corp
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Abstract

The invention is a method of determining the content of platinum, europium and and cerium element in the reforming catalyst. The method is as follows: determine the prepared standard sample containing the platinum, europium and cerium element by the X-ray fluorescent spectrum to get the apparent content and then revise the apparent content to get the real content of platinum, europium and cerium element by the experience equation. The method resolves the problem that the platinum content determining error exceeds the admitted range, brought because of the effect that the europium and cerium element absorbs the platinum in the platinum reforming catalyst containing the europium and cerium element and it has the advantages of easy operation and rapid analysis speed.

Description

A kind of method of measuring platinum in the reforming catalyst, europium, Ce elements content
Technical field
The invention relates to a kind of method of measuring platinum in the reforming catalyst, europium, Ce elements content, the method for further saying so and measuring platinum, europium, Ce elements content in the reforming catalyst with x-ray fluorescence spectrometry about a kind of.
Background technology
Along with the development of petroleum refining industry and the development and the exploitation of catalysis material, very big variation has also taken place in the composition of reforming catalyst, by non-platinum metal oxides catalyzer,, the many metal component catalyzer development two to platiniferous of single platinum (Pt) catalyzer.Recently the adding of research and development the reforming catalyst of rare earth elements europium (Eu) and cerium (Ce), impel people that the content analysis of the Pt in this catalyzer, Eu and Ce element has been proposed new requirement.
To the analysis of each constituent content in the reforming catalyst, have following method to adopt in the prior art:
Spectrophotometric method described in the ASTM 4642-86 can be used for the content of Pt in the analysis of catalyst, and this method is with hydrochloric acid, hydrogen peroxide dissolved samples, behind the adding stannous chloride, goes out Pt content with spectrophotometric determination.This methods analyst takes longer, and sample of unitary determination needs 4 hours, and can not provide the content of Eu and Ce.
Emission of ions spectroscopic methodology described in the GB/T 16484.3 can be used for analyzing the content of rare earth chloride, nitric acid rare earth light rare earth.This method be with sample 120 ℃ of dryings 1 hour, use dissolving with hydrochloric acid again, carry out spectroscopic assay with the plasma light source activation.Because sample will pass through processing procedures such as oven dry, dissolving, take longer, sample need of unitary determination 4 hours, and can not provide the content of Pt simultaneously.
Put down in writing among the RIPP 135-90 and adopted x-ray fluorescence spectrometry to measure the method for reforming catalyst Pt content, but this method is in the reforming catalyst that contains rare earth element Eu, Ce during the Pt Determination on content, can produce following problem, the existence of Eu and Ce, can disturb the Pt Determination on content, Pt content error is 0.03%-0.04%, and this quantitative test for noble metal is unallowed, and this method can not provide the content of Eu and Ce equally.
Summary of the invention
The objective of the invention is on the basis of existing technology, a kind of method that adopts x-ray fluorescence spectrometry can accurately measure platinum in the reforming catalyst, europium and Ce elements content simultaneously is provided.
The method of platinum, europium and Ce elements content comprises the following steps: in the mensuration reforming catalyst provided by the invention
(1) prepares the standard solution of concentration in 0.1-10 mg/ml scope of platinum, europium, cerium respectively;
(2) prepare the catalyzer standard model that different platinum, europium, cerium content and surplus aluminium oxide are formed with the standard solution of step (1);
(3) platinum, europium and cerium characteristic spectral line intensity I in the catalyzer standard model of determination step (2) i, obtain X i=aI i 2+ bI i+ c, wherein, X iBe the apparent content of platinum, europium, cerium, I iBe characteristic spectral line intensity, a, b, c are the coefficient of typical curve equation;
(4) by empirical equation W i=(aI i 2+ bI i+ c) (1+ ∑ A jW j), obtain correction coefficient A j, in empirical equation, ∑ A jW jBe matrix correction item, W jContent for matrix element (j);
(5) measure platinum, the europium of unknown reforming catalyst sample, line strength of Ce elements respectively, obtain the content of platinum, europium, Ce elements by the empirical equation simultaneous solution.
In assay method provided by the invention, said reforming catalyst, it contains by weight the cerium of the platinum of 0.2-0.5%, the europium of 0.02-0.8%, 0.02-0.8% and the alumina support of surplus in forming.
In the said X-fluorescence diffraction assay method, the condition determination of platinum element is that rhodium target, L α analytical line, 2 θ angles are 38.15 °, exciting voltage 30-50KV, excitation current 30-50mA, analyzing crystal LiF1, scintillation counter, gate time 10-30 second.
The condition determination of said europium element and Ce elements is respectively 63.59 ° and 79.09 ° except 2 θ angles, and other condition is identical with platinum element determination condition.
In assay method provided by the invention, platinum described in the step (1), europium, cerium standard solution are to select one or more concentration value preparations in 0.1-10 mg/ml scope, preferably in the concentration range of 0.5-3 mg/ml, select one or more concentration value preparations, the content lower limit of content in catalyst sample of particularly considering europium and cerium is lower, when the standard solution of preparation europium and cerium, general preparation is the standard solution of two or more low and higher concentration values.
In assay method provided by the invention, the preparation of the standard model described in the step (2) is in the catalyzer possibility compositing range of considering, accurately take by weighing alumina support respectively in agate mortar, moistening with distilled water, the platinum standard solution that in agate mortar, accurately adds step (1) preparation again, europium standard solution and cerium standard solution, constantly stir, under infrared lamp, dry then, the cooling back adds ethanol its grinding is uniform powder, powder is changed in the porcelain crucible, in muffle furnace 500-700 ℃ roasting 0.1-10 hour, put into the sample preparation of aluminum sample box after the cooling.Said method for making sample generally is to put into the sample of aluminum sample box, and utilizing compression mold to be pressed into diameter with 5 tons pressure on sheeter is 25 millimeters disk.
Empirical coefficient method is to be used to overcome a kind of Mathematical Correction Method of disturbing between the element, in the methods of the invention, empirical coefficient method is used for proofreading and correct apparent concentration content, and it describes the line strength of element in the sample and the funtcional relationship of content with straight line or quafric curve.In method provided by the invention, said empirical equation W i=(aI 2+ bI+c) (1+ ∑ A jW j) be typical curve equation (aI 2+ bI+c) with matrix correction item ∑ A jW jCombination, it finds the solution the correction coefficient A that obtains between element by the known content of tested element in the standard model series and the relation of line strength j, and then platinum, europium, the cerium line strength of the catalyst sample by measuring unknown element content obtain the constituent content after calibrated.
Assay method provided by the invention has solved in the platinum-reforming catalyst that contains europium and cerium because the platinum content error at measurment that europium and cerium bring the absorption effect of platinum exceeds the problem of allowed band, can be met the content of the platinum element of accuracy and precision requirement.
Assay method provided by the invention is easy and simple to handle, and analysis speed is fast, and under the situation that instrument turns round continuously, the platinum of a sample of unitary determination, europium, cerium content only need 30 minutes.
Embodiment
The following examples will the present invention is described further, but not thereby limiting the invention.
In an embodiment, it is pure that employed nitric acid and hydrochloric acid are analysis, Beijing chemical reagent work product; Platinum filament is a Shanghai Alloy Plant product, and specification is 99.99%; Europium oxide and cerium oxide are spectroscopic pure, chemical reagent station, Shanghai packing manufacturer product; Aluminium oxide is a spectroscopic pure, Shanghai reagent one factory's product.
Used x-ray fluorescence spectrometry instrument is Japanese 3271E x-ray fluorescence spectrometry instrument of science.
Embodiment
1, the preparation of standard solution:
The platinum standard solution of platiniferous 3 mg/ml: platinum filament is washed with watery hydrochloric acid, cleans oven dry with distilled water again.Therefrom accurately take by weighing 0.7502 gram platinum filament then, put into beaker, add 60 milliliters of chloroazotic acid (HCl: HNO 3=3: 1), heating makes it whole dissolvings, transfers to after the cooling in 250 milliliters of volumetric flasks, is diluted with water to scale and shakes equal.
Contain the europium standard solution that europium is respectively 3 mg/ml and 0.5 mg/ml: with europium oxide 500 ℃ of following roastings after 1 hour, accurately taking by weighing 0.8685 gram and 0.1158 restrains in two beakers, add about 60 milliliters of nitric acid of 1: 1 respectively, add and make it whole dissolvings, quantitatively transfer to respectively after the cooling in the volumetric flask of 250 milliliters and 200 milliliters, be diluted with water to scale and shake up.
Contain the cerium standard solution that cerium is respectively 3 mg/ml and 0.5 mg/ml: with cerium oxide 500 ℃ of following roastings after 1 hour, accurately taking by weighing 0.9231 gram and 0.1229 restrains in two beakers, add about 60 milliliters of nitric acid of 1: 1 respectively, add and make it whole dissolvings, quantitatively transfer to respectively after the cooling in the volumetric flask of 250 milliliters and 200 milliliters, be diluted with water to scale and shake up.
2, preparation standard model.Each standard specimen weight is 3 grams, according to 12 standard models of content proportioning preparation of each element shown in the table 1.
Table 1
The standard specimen numbering Platinum (Pt) Europium (Eu) Cerium (Ce) Aluminium oxide (gram)
Standard solution (milliliter) Weight (milligram) Heavy % Standard solution (milliliter) Weight (milligram) Heavy % Standard solution (milliliter) Weight (milligram) Heavy %
??1 ????2.0 ????6.0 ??0.20 ????8.0 ????24.0 ??0.80 ????1.2 ????0.6 ??0.02 ??2.9694
??2 ????2.5 ????7.5 ??0.25 ????1.2 ????0.60 ??0.02 ????2.5 ????7.5 ??0.25 ??2.9844
??3 ????3.0 ????9.0 ??0.30 ????1.5 ????4.5 ??0.15 ????1.5 ????4.5 ??0.15 ??2.9820
??4 ????3.5 ????10.5 ??0.35 ????3.6 ????1.8 ??0.06 ????8.0 ????24.0 ??0.80 ??2.9637
??5 ????4.0 ????12.0 ??0.40 ????2.0 ????6.0 ??0.20 ????4.0 ????12.0 ??0.40 ??2.9700
??6 ????4.5 ????13.5 ??0.45 ????4.0 ????12.0 ??0.40 ????3.0 ????9.0 ??0.30 ??2.9655
??7 ????5.0 ????15.0 ??0.50 ????3.0 ????9.0 ??0.30 ????5.0 ????15.0 ??0.50 ??2.9610
??8 ????2.0 ????6.0 ??0.20 ????7.0 ????21.0 ??0.70 ????2.0 ????6.0 ??0.20 ??2.9670
??9 ????2.5 ????7.5 ??0.25 ????6.0 ????3.0 ??0.10 ????6.0 ????3.0 ??0.10 ??2.9865
??10 ????3.0 ????9.0 ??0.30 ????5.0 ????15.0 ??0.50 ????7.0 ????21.0 ??0.70 ??2.9550
??11 ????3.5 ????10.5 ??0.35 ????6.0 ????18.0 ??0.60 ????6.0 ????18.0 ??0.60 ??2.9535
??12 ????5.0 ????15.0 ??0.50 ????2.5 ????7.5 ??0.25 ????3.6 ????1.8 ??0.06 ??2.9757
The concrete process for preparation of standard sample is: aluminium oxide after 850 ℃ of roastings, is accurately taken by weighing in agate mortar, and water is moistening; Press the platinum shown in the table 1, europium, cerium content, the standard solution that accurately adds platinum, europium, cerium respectively in the agate mortar, stir, under infrared lamp, dry, the cooling back adds ethanol grinds it for uniform powder, changes powder over to porcelain crucible, 650 ℃ of roastings 1 hour, take by weighing 1.5 grams after the cooling and put into aluminum sample box, on sheeter, be compressed to the disk of 25 millimeters of diameters with 5 tons of pressure.
3, the sample disk is packed into put into the sample chamber behind the sample box of instrument, measure line strength of each sample according to condition determination, wherein the X-fluorescence diffraction condition determination of platinum element is rhodium target, L α analytical line, 38.1 5 ° of 2 θ angles, exciting voltage 50KV, excitation current 50mA, analyzing crystal LiF1, scintillation counter, gate time 20 seconds.
The X-fluorescence diffraction condition determination of europium element and Ce elements is respectively 63.59 ° and 79.09 ° except 2 θ angles, and other condition is identical with the condition determination of platinum element.
Obtain the relation curve X of apparent concentration and line strength by the content of platinum, europium, cerium in the standard sample and corresponding line strength match thereof i=aI i 2+ bI i+ c, its coefficient is respectively:
Platinum: a=0, b=0.040389, c=-0.048091;
Europium: a=0, b=0.21078, c=-0.073535;
Cerium: a=0, b=0.80802, c=-0.056898.
4, by empirical equation W i=(aI i 2+ bI i+ c) (1+ ∑ A jW j), obtain correction coefficient A jBe respectively:
When measuring the platinum element, A Eu=0.15225, A Ce=0.11031;
When measuring the europium element, A Pt=-0.035977, A Ce=0.073535;
When measuring Ce elements, A Pt=-0.053913, A Eu=-0.017229.
5, the catalyst sample of 5 unknown content is measured.
Respectively with the correction coefficient A of aforementioned calculation jAnd in coefficient a, b, the c input computing machine, with the sample sample preparation and measure line strength, find the solution the content that obtains platinum, europium, cerium by simultaneous equations, the constituent content measurement result of sample sees Table 2.
As a comparison, the sample of above-mentioned 5 the unknowns adopts the described spectrophotometric method of ASTM 4642-86 to obtain the content of platinum element, adopts GB/T 16484.3 described emission of ions spectroscopic methodologies to obtain the content of rare-earth europium and Ce elements, the results are shown in Table 2.
Table 2
Sample number into spectrum Pt (heavy %) Eu (heavy %) Ce (heavy %)
This method ??ASTM ?4642-86 This method ??GB/T ?16484.3 This method ??GB/T ?16484.3
?1 ?0.27 ???0.29 ?0.13 ?0.12 ?0.28 ?0.28
?2 ?0.28 ???0.27 ?0.24 ?0.24 ?0.62 ?0.60
?3 ?0.34 ???0.33 ?0.28 ?0.27 ?0.17 ?0.18
?4 ?0.28 ???0.28 ?0.045 ?0.049 ?0.046 ?0.055
?5 ?0.29 ???0.29 ?0.052 ?0.054 ?0.14 ?0.14
As can be seen from Table 2, adopt the result of platinum that assay method provided by the invention obtains, europium, Ce elements content, with with existing method ASTM 4642-86 and GB/T 16484.3 through measuring resulting basically identical as a result respectively, and the inventive method has the advantages that to provide three kinds of constituent contents simultaneously.

Claims (4)

1, a kind of method of measuring platinum in the reforming catalyst, europium, Ce elements content is characterized in that this method comprises the following steps:
(1) prepares the standard solution of concentration in 0.1-10 mg/ml scope of platinum, europium, cerium respectively;
(2) prepare the catalyzer standard model that different platinum, europium, cerium content and surplus aluminium oxide are formed with the standard solution of step (1);
(3) platinum, europium and cerium characteristic spectral line intensity I in the catalyzer standard model of determination step (2) i, obtain X i=aI i 2+ bI i+ c, wherein, X iBe the apparent content of platinum, europium, cerium, I iBe characteristic spectral line intensity, a, b, c are the coefficient of typical curve equation;
(4) by empirical equation W i=(aI i 2+ bI i+ c) (1+ ∑ A jW j), obtain correction coefficient A j, in empirical equation, ∑ A jW jBe matrix correction item, W jContent for matrix element (j);
(5) measure platinum, the europium of unknown reforming catalyst sample, line strength of Ce elements respectively, obtain the content of platinum, europium, Ce elements by the empirical equation simultaneous solution.
2,, it is characterized in that containing by weight the cerium of the platinum of 0.2-0.5%, the europium of 0.02-0.8%, 0.02-0.8% and the alumina support of surplus in the composition of described reforming catalyst according to the said method of claim 1.
3, according to the said method of claim 1, it is characterized in that in the condition determination of platinum element, europium element and Ce elements, 2 θ angles are respectively 38.15 °, 63.59 ° and 79.09 °, and other conditions are rhodium target, L α analytical line, exciting voltage 30-50KV, excitation current 30-50mA, analyzing crystal LiF1, scintillation counter, gate time 10-30 second.
4,, it is characterized in that said platinum, europium, cerium standard solution are to select one or more concentration value preparations in the concentration range of 0.5-3 mg/ml according to the said method of claim 1.
CNB011237627A 2001-07-31 2001-07-31 Method for determining content of Pt, Eu and Ce elements in reformed catalyst Expired - Lifetime CN1156690C (en)

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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN100454008C (en) * 2005-06-22 2009-01-21 重庆大学 Method of measuring single solute solution concentration using compton scattering
CN100491979C (en) * 2006-04-12 2009-05-27 新源动力股份有限公司 A method for determining proton exchange film fuel cell film electrode platinum loading
CN101799437B (en) * 2009-02-06 2011-12-07 中国石油天然气股份有限公司 Method for measuring contents of phosphorus and iron in cocatalyst by X-ray fluorescence method
CN101750404B (en) * 2008-12-12 2012-05-23 中国科学院沈阳自动化研究所 Method for correcting plasma emission spectral line self-absorption effect
CN105717151A (en) * 2014-12-03 2016-06-29 中国石油天然气股份有限公司 Method for measuring platinum and samarium elements in reforming catalyst
CN105738386A (en) * 2016-03-09 2016-07-06 陈立 Method for analyzing total quantity of light-rear-earth lanthanum metal and its compounds by using Gamma-spectroscopy
CN105806854A (en) * 2016-03-09 2016-07-27 邓晓钦 Method for analyzing grades of light rare earth ore and concentrate thereof by gamma energy spectrum method
CN108663389A (en) * 2017-03-29 2018-10-16 上海宝钢工业技术服务有限公司 The x-ray fluorescence assay method of lead and rapid determination of content of cadmium element in aluminium alloy

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN100454008C (en) * 2005-06-22 2009-01-21 重庆大学 Method of measuring single solute solution concentration using compton scattering
CN100491979C (en) * 2006-04-12 2009-05-27 新源动力股份有限公司 A method for determining proton exchange film fuel cell film electrode platinum loading
CN101750404B (en) * 2008-12-12 2012-05-23 中国科学院沈阳自动化研究所 Method for correcting plasma emission spectral line self-absorption effect
CN101799437B (en) * 2009-02-06 2011-12-07 中国石油天然气股份有限公司 Method for measuring contents of phosphorus and iron in cocatalyst by X-ray fluorescence method
CN105717151A (en) * 2014-12-03 2016-06-29 中国石油天然气股份有限公司 Method for measuring platinum and samarium elements in reforming catalyst
CN105717151B (en) * 2014-12-03 2018-11-16 中国石油天然气股份有限公司 Method for measuring platinum and samarium elements in reforming catalyst
CN105738386A (en) * 2016-03-09 2016-07-06 陈立 Method for analyzing total quantity of light-rear-earth lanthanum metal and its compounds by using Gamma-spectroscopy
CN105806854A (en) * 2016-03-09 2016-07-27 邓晓钦 Method for analyzing grades of light rare earth ore and concentrate thereof by gamma energy spectrum method
CN108663389A (en) * 2017-03-29 2018-10-16 上海宝钢工业技术服务有限公司 The x-ray fluorescence assay method of lead and rapid determination of content of cadmium element in aluminium alloy

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