A kind of method of fast measuring carbon content in solid catalyst
Technical field
The present invention relates to a kind of mensuration that is used for industries such as Coal Chemical Industry, methanol-to-olefins, petrochemical complex, petroleum refining to carbon content on the catalyzer, specifically, relate to a kind of method of fast measuring carbon content in solid catalyst.
Background technology
The assay method of carbon content in solid catalyst mainly contains at present: 1, thermogravimetry (TG) obtains the sedimental amount of whole carbon distributions (C, H summation); 2, iron and steel is decided carbon method (standard GB/T 223.69-1997), in tubular furnace, under the high temperature blowing air condition carbon perfect combustion on the catalyzer of known weight is generated carbon dioxide, gas after the burning is passed through the standard hydrogen potassium oxide solution, volume differences is the carbon dioxide volume, obtains carbon content on the catalyzer through converting; 3, the carbon dioxide that utilizes the burning back to generate is dissolved into the variation that alkali lye causes electrical conductivity of solution, and the reference material external standard by with known carbon content obtains coke on regenerated catalyst.4, according to standard GB/T7730.5-2000, utilize infrared as detection means, the infrared energy of the carbon dioxide absorption specific wavelength that burning back generates, its absorption can be directly proportional with the concentration of carbon, can obtain carbon content on the catalyzer.5, burning gases gas chromatographic detection method, Xu Chunming etc. (Chinese patent application number 96211983.0) develop a kind of carbon determination method, promptly utilize chromatographic column separation and thermal conductivity detector (TCD) detection in the gas chromatography, the amount of carbon distribution burning generation carbon dioxide on the catalyzer can be measured, thereby carbon content on the catalyzer can be obtained.
In the above-mentioned various assay method, it is complicated that iron and steel is decided general operations such as carbon method and electrical conductivity method, and minute is longer, and need periodic replacement standard alkali lye.The infrared analysis analysis precision is higher, generally is useful in line analysis, and equipment is expensive.Chromatography needs calibrating gas to carry out quantitatively, and aftertreatment needs precision higher.
Because carbon content is bigger to catalyst activity, selectivity influence on the catalyzer, measure timely and accurately in commercial production such as Coal Chemical Industry, methanol-to-olefins, petrochemical complex, petroleum catalytic cracking, petroleum refining especially that carbon content plays an important role to instructing to produce on the catalyzer.
Summary of the invention
The object of the present invention is to provide a kind of method of fast measuring carbon content in solid catalyst.
For achieving the above object, the method of fast measuring carbon content in solid catalyst provided by the invention, the sample at first known to carbon content, that character is identical carries out uv drs and measures, obtain the absorbance of wavelength correspondence, and carbon content and absorbance made regression analysis equation, then unknown carbon content, catalyzer that character is identical are made uv drs spectrum and obtain absorbance, directly obtain carbon content with its absorbance correspondence according to regression analysis equation.
Described method, wherein absorbance is the absorbance of single wavelength, or the formula of the absorbance of a plurality of wavelength calculates.
Described method, wherein testing sample is directly to measure.
Described method, wherein testing sample evenly mixes back mensuration with uv drs with reference material.
Described method, wherein carbon distribution after the catalyzer of the same nature process differential responses process has different regression analysis equations.
Described method, wherein the solid catalyst of same nature has different regression analysis equations after its reaction with after the regeneration when being used for ciculation fluidized reaction.
Assay method provided by the invention is applicable in the industries such as Coal Chemical Industry, methanol-to-olefins, petrochemical complex, petroleum refining the mensuration to carbon content on the catalyzer.
Description of drawings
Fig. 1 is the linear relationship of the different carbon content of catalyzer and absorbance in the embodiment of the invention 1.
Fig. 2 is the linear relationship of the different carbon content of catalyzer and absorbance in the embodiment of the invention 2.
Embodiment
The present invention adopts uv drs spectrographic determination carbon content in solid catalyst.Some at first known to carbon content, that character is identical catalyzer carry out the uv drs spectroscopic assay, and the absorbance and the carbon content of selected a certain wavelength are done regretional analysis, can obtain regression equation and coefficient of determination R
2Also can select the absorbance of a plurality of wavelength, it be carried out formula calculate, the result that it obtains and the carbon content of catalyzer are done regretional analysis, obtain regression equation and coefficient of determination R
2R
2It is good more to approach 1 fitting degree more greatly or more.Then unknown carbon content, catalyzer that character is identical are carried out the uv drs spectroscopic assay,, can directly obtain coke on regenerated catalyst according to regression analysis equation.Carry out catalyzer when measuring with uv drs, can add the reference material that uv drs spectrum uses (as barium sulphate etc.) as required, evenly mix, measure behind the compressing tablet.If the catalyzer of same nature carries out ciculation fluidized reaction, because the character of the catalyst carbon after reaction back and the regeneration and content etc. have certain difference, therefore resulting regression analysis equation also is different.The catalyzer of same nature is through carbon distribution after the differential responses, and the carbon content of catalyzer is different with the regression analysis equation that absorbance is produced.
By the following examples the present invention is made detailed description, but the present invention is not limited to these embodiment.
Embodiment 1
Dalian Chemical Physics Research Institute's development methanol-to-olefins catalyzer, the sample of different carbon contents is got in the recirculating fluidized bed reaction in the reactor lower end.Adopt the method for thermogravimetric that the carbon content of each sample is measured, and each sample is carried out uv drs measure, what obtain the results are shown in Table 1.
The carbon content of table 1 catalyzer and uv drs measurement result
The catalyzer numbering |
Carbon content (wt%) |
Absorbance A
1 |
Absorbance A
2 |
Absorbance A
3 |
Absorbance A
4 |
λ
192 |
λ
270 |
λ
641 |
(λ
641-λ
192)/(λ
270-λ
192)
|
D1 |
3.45 |
0.0682 |
0.1783 |
0.1198 |
0.4687 |
D2 |
4.05 |
0.1145 |
0.1996 |
0.1604 |
0.5394 |
D3 |
4.88 |
0.0552 |
0.1830 |
0.1449 |
0.7019 |
D4 |
6.08 |
0.0131 |
0.1713 |
0.1505 |
0.8685 |
D5 |
6.51 |
0.0190 |
0.164 |
0.157 |
0.9517 |
D6 |
6.93 |
0.0635 |
0.2541 |
0.2568 |
1.0142 |
D7 |
7.30 |
0.0220 |
0.2000 |
0.2117 |
1.0657 |
D8 |
7.40 |
0.0174 |
0.2114 |
0.228 |
1.0856 |
D9 |
8.58 |
0.0581 |
0.2437 |
0.3047 |
1.3287 |
To absorbance A
4Make linear relationship with carbon content, obtain equation of linear regression and coefficient of determination, the results are shown in Figure 1.
Unknown carbon content catalyzer D10 carries out uv drs and measures, and the results are shown in Table 2.Again according to equation of linear regression y=6.0709x+0.7184, can obtain directly that carbon content is 6.23wt% on the catalyzer.The thermogravimetric result of this catalyzer is 6.27%, and as being actual value with the thermogravimetric result, the result that uv drs is measured and the absolute error of actual value are 0.04wt%, and relative error is 0.64%.
The unknown carbon content catalyzer of table 2 uv drs measurement result
The catalyzer numbering |
Absorbance A
1 |
Absorbance A
2 |
Absorbance A
3 |
Absorbance A
4 |
λ
192 |
λ
270 |
λ
641 |
(λ
641-λ
192)/(λ
270-λ
192)
|
D10 |
0.0453 |
0.197 |
0.1831 |
0.9084 |
Embodiment 2
Dalian Chemical Physics Research Institute's development methanol-to-olefins catalyzer, the sample of different carbon contents is got in the recirculating fluidized bed reaction in the regenerator lower end.Adopt the method for thermogravimetric that the carbon content of each sample is measured, and each sample is carried out uv drs measure, what obtain the results are shown in Table 3.
The carbon content of table 3 catalyzer and uv drs measurement result
The catalyzer numbering |
Carbon content (wt%) |
Absorbance A
5 |
λ
630 |
D11 |
0.00 |
0.0609 |
D12 |
0.76 |
0.1051 |
D13 |
1.05 |
0.1155 |
D14 |
1.10 |
0.1225 |
D15 |
1.39 |
0.1265 |
D16 |
2.16 |
0.1723 |
D17 |
2.50 |
0.1912 |
D18 |
3.24 |
0.2149 |
D19 |
3.70 |
0.2567 |
D20 |
3.96 |
0.2738 |
To absorbance A
4Make linear relationship with carbon content, obtain equation of linear regression and coefficient of determination, the results are shown in Figure 2.
Unknown carbon content catalyzer D21 carries out uv drs and measures, and the results are shown in Table 4.Can obtain directly according to equation of linear regression y=19.18x-1.1589 again that carbon content is 1.50wt% on the catalyzer.The thermogravimetric result of this catalyzer is 1.51%, and as being actual value with the thermogravimetric result, the result that uv drs is measured and the absolute error of actual value are 0.01wt%, and relative error is 0.67%.
The unknown carbon content catalyzer of table 4 uv drs measurement result
The catalyzer numbering |
Absorbance A
5 |
λ
630 |
D21 |
0.1385 |