CN115808401A - Rapid analysis method for accessibility of acid centers in porous solid particles - Google Patents
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Abstract
The invention relates to a method for rapidly analyzing accessibility of acid centers in porous solid particles, which comprises the following steps: s1, preparing an alkaline probe molecular solution by adopting an organic alkaline compound and a solvent, and putting the alkaline probe molecular solution into a stirring container of an analysis testing system, wherein the analysis testing system can analyze and detect the concentration of the organic solution in real time under an anhydrous condition; s2, starting a testing system, quickly adding 0.1-10 g of a catalyst sample to be tested into the stirring container after a signal to be tested is stable, and continuously monitoring the change of the detection signal in real time; and S3, obtaining an adsorption rate curve of the alkaline probe molecule solution according to the detection signal obtained by real-time monitoring, wherein the initial slope of the curve is a parameter for judging the accessibility of the catalyst acid center, and the adsorption quantity corresponding to the platform of the curve is a parameter for judging the total accessibility of the catalyst acid center. The method is suitable for rapid analysis of the accessibility of the acid center of the porous solid acid catalytic material.
Description
Technical Field
The invention belongs to the field of petrochemical catalyst research, and particularly relates to a rapid analysis method for accessibility of an acid center in porous solid particles.
Background
The heavy oil processing technology can convert heavy oil into high value-added products, and how to convert heavy oil molecules into small molecular compounds to the maximum extent becomes an important issue in the field of petroleum refining at present. The Fluid Catalytic Cracking (FCC) technology is the core technology of heavy oil processing in refineries, and the accessibility of active centers (acid centers) within FCC catalyst particles to heavy oil molecules is the key to limiting the conversion efficiency. Thus, rapid analysis of accessibility of acid sites within catalyst particles is of great significance for evaluation of catalyst performance during catalyst development and use.
Currently, the evaluation of The acid performance of solid acid catalysts is mainly carried out by n-butylamine titration (C. Walling, J. Am. Chem. Soc.72 (1950) 1164-1168.), pyridine adsorption in situ infrared spectroscopy (Py-FTIR) (The Journal ofPhysical Chemistry,1982,86 (10): 1760-1763; journal of Catalysis,1984,89 (2): 185-195), ammonia temperature programmed desorption technique (NH) 3 TPD) (Zeolite, 1984,4 (1): 9-14.) whose information on acid type, acid amount and acid strength distribution was investigated. However, while accessibility of acid sites has been a key factor in influencing FCC catalyst performance, accessibility of acid sites has not been a key parameter for evaluating catalyst performance due to the lack of a rapid and convenient analytical method.
A method that can be used for the study of the accessibility of the acid sites to the solid acid catalyst is the in situ infrared spectroscopy technique, n.s. nesterenko et al (microporus and mesopore materials.2004,71 157-166.) the accessibility of the acid sites within the mordenite channels was studied using CO and alkylpyridines as probe molecules using the in situ infrared spectroscopy technique. However, this method has several disadvantages: firstly, the in-situ infrared spectroscopy requires harsh experimental conditions under vacuum conditions, the experimental process is complicated, and the analysis of a group of samples requires 2-3 days, so that the in-situ infrared spectroscopy is not suitable for rapid analysis; secondly, the method requires the grinding and tabletting treatment of the sample, so the method is not suitable for the analysis and determination of the accessibility of the acid center in the formed catalyst particle; thirdly, the method requires that the selected alkaline probe molecules have higher saturated vapor pressure, so that the method is not suitable for selecting macromolecular alkaline compounds capable of simulating heavy oil molecules to carry out evaluation experiments; and fourthly, because the infrared spectroscopy is a semi-quantitative method, the method cannot accurately quantify the accessibility of the acid center, and in addition, the in-situ infrared spectroscopy also has the defect that the infrared accessory and the infrared spectrometer are expensive, so the method is not suitable for wide popularization.
CN1513112A discloses a method and a device for detecting the accessibility of porous materials to large compounds, the invention relates to a method for detecting the accessibility of porous materials to large compounds of generally high molecular weight and correlating said accessibility to the accessibility of porous materials under application conditions. The method disclosed by the invention only focuses on the accessibility of the macromolecular compound to the catalyst pore channel, and the macromolecular compound is a non-basic compound which cannot realize the evaluation and analysis of the accessibility of the catalyst acid center.
Disclosure of Invention
In order to solve the problems of the prior art described above, it is an object of the present invention to provide a method for rapidly analyzing accessibility of acid sites within catalyst particles. The method is suitable for the analysis departments of petrochemical research institutes and petroleum refineries to quickly evaluate the acid performance of the catalyst.
To this end, the present invention provides a method for rapid analysis of accessibility of acid centers within porous solid particles, comprising the steps of:
s1, preparing an alkaline probe molecular solution by adopting an organic alkaline compound and a solvent, and putting the alkaline probe molecular solution into a stirring container of a test system, wherein the test system can analyze the concentration of the organic solution in real time under an anhydrous condition;
s2, starting a testing system, quickly adding a sample to be tested into the stirring container after a signal to be tested is stable, and continuously monitoring the change of the detection signal in real time;
and S3, obtaining the concentration of the corresponding alkaline probe molecule solution according to the detection signal obtained by real-time monitoring, then calculating the real-time adsorption quantity of the sample to be detected to the alkaline probe molecules, and then drawing by the square root of the real-time adsorption quantity and time to obtain an adsorption rate curve of the alkaline probe molecule solution, wherein the initial slope of the curve is a parameter for judging the accessibility of the acid centers in the sample to be detected, and the adsorption quantity corresponding to the platform of the curve is a parameter for judging the total accessibility of the acid centers in the sample to be detected.
The rapid analysis method according to the present invention is preferably such that the test system comprises: a stirring vessel capable of being isolated from water vapor, an on-line analysis detector for the concentration of the organic solution, a circulating pump, and a pipe fitting for connecting the above components.
In the rapid analysis method according to the present invention, it is preferable that the stirring container capable of being isolated from water vapor is a container protected by an inert gas (gas that does not react with the sample to be measured and the alkaline probe molecule solution), and the volume of the container is 50 to 500ml.
In the rapid analysis method according to the present invention, it is preferable that the on-line organic solution concentration analysis detector is an ultraviolet or fluorescence detector equipped with an in-situ cell.
The rapid analysis method according to the present invention, wherein the in-situ cell is preferably a cuvette, and the volume of the cuvette is 5 μ l to 1.5ml, preferably 50 μ l to 500 μ l.
The rapid analysis method according to the present invention, wherein the circulation pump is preferably a small-volume peristaltic pump or a plunger pump with a smooth flow rate.
In the rapid analysis method according to the present invention, it is preferable that the basic probe molecules in the basic probe molecule solution include a basic organic compound having a pyridine nitrogen group and an amino nitrogen group, and at least one selected from quinoline, acridine and naphthylamine molecules is preferable.
In the rapid analysis method according to the present invention, it is preferable that the solvent in the basic probe molecule solution is a nonpolar organic solution, preferably selected from the group consisting of C7-C10 normal or iso-alkanes or their mixtures, C6-C8 aromatic hydrocarbons or their mixtures, carbon tetrachloride, chloroform and CS 2 At least one of (a).
The rapid analysis method according to the present invention, wherein the concentration of the alkaline probe molecule solution is preferably 10 -9 ～10 -2 mol/L, more preferably 10 -7 ～10 -2 mol/L, more preferably 0.1 to 10mmol/L; the sampling amount of the sample to be tested is 0.1-10 g, and more preferably 0.5-2 g.
In the rapid analysis method according to the present invention, it is preferable that the porous solid particles are spherical granular porous solids having a particle size of 5 to 150 μm.
The rapid analysis method according to the present invention, wherein the porous solid is preferably an FCC catalyst, and the FCC catalyst includes fresh FCC catalyst, used FCC catalyst and deactivated FCC catalyst.
In the rapid analysis method according to the present invention, preferably, the porous solid is a porous solid acid catalyst, and the porous solid acid catalyst requires a dehydration treatment of the catalyst, and more preferably, the dehydration treatment temperature is 100 to 350 ℃.
The method for rapidly analyzing the accessibility of the acid centers in the porous solid particles, disclosed by the invention, has the advantages of rapidness, convenience and low price.
The invention discloses a method for rapidly analyzing accessibility of acid centers in porous solid particles, which specifically comprises the following steps:
the method comprises the following steps: preparation of analytical instruments and reagents
The method needs a set of analysis and test system capable of analyzing and detecting the concentration change of the alkaline probe molecule solution in real time under the anhydrous condition, and the analysis and test system comprises: an air-insulated stirrable vessel, an on-line monitoring detector, a circulation pump, and tubing connecting these components.
Suitable organic basic compounds are screened as basic probe molecules, which may comprise all basic organic compounds with pyridine nitrogen and amino nitrogen groups.
Step two: preparation of analysis solution
The method requires that alkaline probe molecules and a solvent are strictly dehydrated and purified, alkaline organic compounds with certain mass (volume) are accurately weighed (measured), firstly dissolved in a small amount of solvent, and then transferred into a volumetric flask for constant volume to prepare a solution with certain concentration for later use. The alkaline probe molecule solution is a dilute solution, and the specific concentration depends on the dissolution condition of the selected solute in the selected solvent, and is particularly selectable within the range of 0.1-10 mmol/L.
Step three: preparation of samples to be tested
The method requires that the particle size distribution of a sample to be tested is narrow, so that the catalyst sample needs to be screened, and the selection of the particle size depends on the most probable particle size of the tested catalyst sample, and is particularly selectable within the range of 5-150 mu m; the method requires that a sample to be detected is subjected to activation treatment, so that the sample to be detected needs to be subjected to dehydration treatment, the roasting temperature of the activation treatment depends on the actually-tolerated roasting temperature of the sample to be detected, and the roasting temperature is selected from the range of 150-600 ℃, and is preferably 150-350 ℃; and the sample does not contact water vapor in the whole experimental process for standby.
Step four: specific experimental operating process
Firstly, quickly transferring a quantitative solution into a stirring container of the analysis and test system in the first step, starting a circulating system, starting a detector to record a signal of the initial solution, quickly adding a quantitative sample to be analyzed in the second step after the signal to be detected is stable, continuously monitoring the signal change in real time, wherein the sampling amount of the catalyst is 0.1-10 g, preferably 0.5-2 g.
Step five: data result processing
Calculating the real-time adsorption quantity of a sample to be detected to the basic probe molecule according to the solution concentration corresponding to the detection signal recorded in real time, and then drawing a graph by using the square root of the real-time adsorption quantity and time to obtain an adsorption rate curve of the basic probe molecule solution, wherein the initial slope of the curve is a parameter for judging the accessibility of the catalyst acid center, and the adsorption quantity corresponding to the platform of the curve is a parameter for judging the accessibility total quantity of the catalyst acid center.
The set of analysis and test system capable of monitoring the concentration change of the alkaline probe molecular solution in real time in the step one is characterized in that the stirring container capable of isolating water vapor is a round-bottomed flask or a self-made container protected by nitrogen atmosphere, and the proper volume is 50-500 ml.
The analysis and test system capable of monitoring the concentration change of the alkaline probe molecule solution in real time in the step one is characterized in that the online detector is an ultraviolet detector or a fluorescence detector, the online detector is required to be capable of automatically recording data, and the counting frequency is not lower than 1 time/second during automatic detection, so that the change of the solution concentration can be monitored online in real time. An ultraviolet spectrophotometer is preferred as the detector, and the wavelength selected depends on the nature of the probe molecule and the solvent.
The set of online analysis test system capable of monitoring the concentration change of the alkaline probe molecule solution in real time in the step one specifically needs to be realized by arranging a special flowing cuvette, specifically requires that the volume of the selected cuvette is small, specifically 5-1.5 ml can be selected, and 50-500 μ l is preferred, so that the change of the solution concentration can be reflected as soon as possible by a signal at a detector end.
The analysis and test system capable of monitoring the concentration change of the alkaline probe molecule solution in real time is characterized in that the circulating pump can be a small-size peristaltic pump or a piston pump, the flow rate of the pump is required to be stable, the conveying speed can be 1-50ml/min, and the change of the concentration of the solution can be reflected as soon as possible by signals at the detector end.
In the set of analysis and test system capable of monitoring the concentration change of the alkaline probe molecule solution in real time in the step one, in order to prevent catalyst particles from entering a detection system to interfere with a detection signal, the solution can leave the stirring container only after strict filtration.
In the analysis and test system capable of monitoring the concentration change of the alkaline probe molecular solution in real time in the step one, the solution circulates between the stirring container and the detector and needs a pipeline of a connection system, the material of the connection pipe needs oil resistance and alkali corrosion resistance, the pipe diameter size is selected according to the conveying speed of the pump, and is preferably selected from 1-10mm, and is preferably selected from 3-6mm.
And step five, specifically processing the data result, namely preparing a series of solutions with known concentrations by using the optimized alkaline probe molecules, drawing a standard curve, and obtaining the corresponding relation between the detection signals of the detector and the concentrations of the solutions. Therefore, the detection signals recorded in real time in the experimental analysis process can be converted into the corresponding solution concentration in real time, the real-time relative concentration and the square root of time are plotted, the initial slope of the obtained curve can represent the adsorption rate of the sample to be detected on the probe molecules, the opposite number of the slope value is defined as the parameter of the accessibility of the acid center of the sample to be detected and is named as the ACI value, and the concentration value corresponding to the platform of the curve can be used for calculating the total accessibility of the acid center of the catalyst.
The invention has the following beneficial effects:
the testing device required by the technology of the invention has low hardware price, simple operation and no special requirement on operators, can finish one-time testing within 30 minutes, meets the requirement of rapid analysis on accessibility of acid centers in porous solid particles (such as porous solid acid catalysts and catalytic cracking catalyst particles), and can be widely applied to rapid evaluation work of acidic solid catalysts.
Drawings
FIG. 1 is a graph showing the relative concentration change of the alkaline probe A-1 n-octane solution adsorbed by four FCC catalysts (Cat-1, 2,3, 4) measured in example 1.
FIG. 2 is a graph showing the relative concentration change of the solution of the alkaline probe A-2 in n-octane adsorbed by four FCC catalysts (Cat-1, 2,3, 4) measured in example 1.
FIG. 3 is a graph showing the relative concentration change of the solution of the non-basic probe NA-1 n-octane adsorbed by the four FCC catalysts (Cat-1, 2,3, 4) measured in example 2.
FIG. 4 is a graph of the acid center accessibility of two FCC catalysts (Cat-1, 4) as measured by in situ infrared spectroscopy in example 5.
Detailed Description
The following examples illustrate the invention in detail: the present example is carried out on the premise of the technical scheme of the present invention, and detailed embodiments and processes are given, but the scope of the present invention is not limited to the following examples, and the experimental methods without specific conditions noted in the following examples are generally performed according to conventional conditions.
Examples 1-1 to 1-4
The method comprises the following steps: preparation of analytical instruments and reagents
The analysis test system capable of monitoring the concentration change of the alkaline probe molecule solution in real time comprises: a magnetic stirrer, a 250ml three-neck round-bottom flask, a UV-1801 model ultraviolet-visible spectrophotometer, a 25 mu l flow cell cuvette, a peristaltic pump hose with an inner diameter of 3mm as a connecting pipe, a porous metal filter with a pore diameter of 1 mu m, and a computer for recording detection signals of the ultraviolet-visible spectrophotometer in real time. In this example, acridine was selected as an alkaline probe molecule, and pure octane was analyzed as a solvent.
Step two: preparation of analysis solution
The purchased analysis alkaline probe molecules A-1 (quinoline) and n-octane are dehydrated by a 5A molecular sieve, a certain amount (see table 1) of A-1 is accurately weighed, firstly dissolved in a small amount of n-octane, then transferred into a 1000ml volumetric flask, and subjected to constant volume by using n-octane to prepare a solution with the concentration of 1mmol/l for later use.
Step three: preparation of catalyst samples
In this example, a series of fresh FCC catalysts (Cat-1, 2,3,4 correspond to examples 1-1 to 1-4, respectively) were selected as analytical samples, sieved, 300-200 mesh (53-75 μm) samples were retained (the catalyst samples were not crushed), calcined at 350 ℃ overnight, and the calcined samples were air-cooled for future use.
Step four: specific experimental operating process
Firstly, 100ml of quinoline solution prepared in the second step is measured and added into the 250ml three-neck flask extracted in the first step, nitrogen is adopted to replace air to conduct water vapor isolation treatment, and a peristaltic pump is started to start circulation of the solution in the system. Taking an n-octane solution as a reference solution, setting a spectrophotometer to be 0, detecting once per second by adopting a wavelength of 314nm and starting to record a signal of an initial solution, adding 1g of FCC catalyst prepared in the third step into the solution after the signal to be detected is stable (about 10 minutes), starting magnetic stirring, continuously monitoring the signal change in real time, and recording for 10 minutes.
Step five: and (3) processing data results, calculating solution concentration values corresponding to the absorbances according to a drawn standard curve according to absorbance signal values recorded by an ultraviolet-visible spectrophotometer in real time, drawing a graph by the square root of relative concentration and time, and calculating the ACI value of each catalyst for the alkaline probe A-1, wherein the obtained results are shown in figure 1, figure 2 and table 1.
Table 1 shows the ACI and AAI values for each FCC catalyst calculated from the curves obtained in figures 1,2 and 3, respectively, and the BAA value for the catalyst obtained from the in situ infrared spectroscopy technique of figure 4, and a comparison of the average time spent in each set of data.
Examples 1 to 11
This example is substantially the same as example 1-1, except that: the type and amount of the alkaline probe molecules, alkaline probe molecule A-2, referred to as acridine, are shown in Table 1.
Examples 1 to 21
This example is substantially the same as examples 1-2, except that: the type and amount of the alkaline probe molecules, alkaline probe molecule A-2, referred to as acridine, are shown in Table 1.
Examples 1 to 31
This example is substantially the same as examples 1-3, except that: the type and amount of the alkaline probe molecules, alkaline probe molecule A-2, referred to as acridine, are shown in Table 1.
Examples 1 to 41
This example is substantially the same as examples 1-4, except that: the type and amount of the alkaline probe molecules, alkaline probe molecule A-2, referred to as acridine, are shown in Table 1.
Comparative examples 1 to 1
This comparative example 1-1 is substantially the same as example 1-1 except that:
the probe molecule used in this comparative example was a non-basic compound, NA-1 porphyrin (the probe molecule used in this comparative example was CN 1513112A), and the value of the Accessibility Index (AAI) of each catalyst was calculated to compare the difference between the results of experiments using basic and non-basic organic compounds as probe molecules, and the results obtained in this example are shown in FIG. 3 and Table 1.
Comparative examples 1 to 2
Comparative examples 1-2 are substantially the same as examples 1-2, except that:
the probe molecule selected in this comparative example was a non-basic compound NA-1 porphyrin (the probe molecule used in this comparative example was CN 1513112A), and the AAI value of each catalyst was calculated to compare the difference in the experimental results obtained by using the basic and non-basic organic compounds as probe molecules, and the results obtained in this example are shown in FIG. 3 and Table 1.
Comparative examples 1 to 3
Comparative examples 1 to 3 are substantially the same as examples 1 to 3 except that:
the probe molecule used in this comparative example was a non-basic compound NA-1 porphyrin (the probe molecule used in this comparative example belongs to the publication CN 1513112A), and the AAI value of each catalyst was calculated to compare the difference between the experimental results obtained by using basic and non-basic organic compounds as probe molecules, and the results obtained in this example are shown in FIG. 3 and Table 1.
Comparative examples 1 to 4
Comparative examples 1 to 4 are substantially the same as examples 1 to 4 except that:
the probe molecule selected in this example is non-basic compound NA-1 porphyrin (the probe molecule used in this example belongs to the published patent CN 1513112A), and the AAI value of each catalyst is calculated to compare the difference between the experimental results obtained by using basic and non-basic organic compounds as probe molecules, and the results obtained in this example are shown in FIG. 3 and Table 1.
Example 3
This example is substantially the same as example 1-1, except that:
the solvent used in this example was petroleum ether (90-120 deg.C), and the difference between the mixed alkane solvent and n-octane solvent was compared, and the results confirmed that cheaper petroleum ether (90-120 deg.C) could be used instead of n-octane.
Example 4
This example is substantially the same as example 1-1, except that:
the solvent selected in this example is xylene, and the difference between the aromatic hydrocarbon solvent and the n-octane solvent is compared, and as a result, it is found that, for the same catalyst sample, the ACI value obtained by using xylene as the solvent is smaller, and it can be considered that a certain competitive adsorption relationship exists between the aromatic hydrocarbon solvent and the aromatic basic probe molecules on the catalyst.
However, the order of the ACI values obtained with xylene as solvent for the different catalyst samples was consistent with the results obtained in example 1. Thus, to avoid the influence of the solvent, the series of comparative experiments required the use of the same solvent.
Example 5
In this example, an in-situ infrared spectroscopy technology was used to test the accessibility of the acid center of a catalyst sample, and a Frontier fourier transform infrared spectrometer (Perkin-Elmer, usa) was used in conjunction with an in-situ high vacuum adsorption and desorption apparatus (manufactured by the institute of chemico-physical research, mass of the chinese academy) (note that the apparatus is expensive, and has high maintenance difficulty and cost).
Preparation of samples: firstly, grinding microspherical catalyst samples with the particle size of 100 mu m into powder (note: catalyst particles need to be crushed), and then pressing into two self-supporting thin slices (15 +/-0.5 mg/cm) with the same mass as much as possible by a tablet press 2 ) (this step requires a high level of operator skill);
acid center test: two sets of the same vacuum systems are needed, firstly, the vacuum systems are vacuumized for 2 hours in advance, two sample pieces are respectively arranged in a specially-made quartz in-situ infrared absorption pool with CaF2 window pieces, the temperature is raised and heated to 673K, and the sample pieces are subjected to high vacuum (10) -3 Pa), naturally cooling to room temperature, respectively adsorbing two alkaline probe molecules (A-4 pyridine and A-3, 6-dimethylpyridine) with different sizes for 1h, then vacuumizing at 150 deg.C for desorption for 1h, cooling to room temperature, and scanning infrared spectrogram. Characteristic bridge hydroxyl on the catalyst before and after the adsorption of alkaline probe molecules (3640 cm) -1 ，
Acid centers) can calculate the accessibility index of such acid centers: (
Identification access availability, BAA value). The infrared data of two alkaline probes with different sizes are required to be tested for the acid center accessibility test of each catalyst sample, the BAA values of Cat-1 and Cat-4 are respectively measured to be 0.55 and 0.30 according to the ratio of the two, the testing process of each alkaline probe needs at least 8 hours, and the total time is 16 hours. Thus, the acid center accessibility test for one catalyst sample requires at least 2 working days, which is very time consuming.
TABLE 1
Compared with the AAI index obtained by adopting non-basic probe molecules such as porphyrin or asphaltene in the comparative example and the capacity of distinguishing accessibility of pore passages in different porous materials, the AAI index obtained by adopting the non-basic probe molecules such as alkaline probe molecules in the examples 1-1 to 1-4 and the non-basic probe molecules in the comparative example are more suitable for distinguishing accessibility of pore passages in different porous materials, and the invention adopts two alkaline probe molecules with different molecular sizes to carry out ACI index determination, so that the difference of accessibility of acid centers on different catalysts can be effectively distinguished, for example, the difference of accessibility of Cat-1 and Cat-4 in the comparative examples 1-1 and 1-4 to the two probes A-1 and A-2 shows that the method is more effective compared with the comparative method, and the method is favorable for analyzing the accessibility of catalytic activity centers of the porous catalysts and provides guiding significance for the design level of the catalysts.
Comparing examples 1-1 to 1-4 using alkaline probe molecules with example 5 using A-3/A-4, it is shown that the accessibility of the acid sites on the catalyst measured by the method of the present invention is consistent with the results provided by example 5, but the time consumption of the analytical test process is greatly reduced, and the rapidity and convenience of the method are fully demonstrated.
Fig. 1 to 4 illustrate the following: FIGS. 1 and 2 are graphs of adsorption rates of alkaline probe molecules of different molecular sizes, respectively, and the difference in adsorption rates is related to the number and accessibility of acid sites in catalyst channels. FIG. 3 shows that the difference of the pore structure difference of the catalyst sample caused by the adsorption rate of the probe molecules is measured by using a non-basic probe NA-1 (porphyrin) provided in the comparative patent method as the adsorbate. FIG. 4 is quantitative data provided in example 5 for the accessibility of the pyridine and 4, 6-lutidine molecules by the acid centers of Cat-1 and Cat-4 catalysts, respectively.
The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and it is therefore intended that all such changes and modifications as fall within the true spirit and scope of the invention be considered as within the following claims.
Claims (12)
1. A method for rapid analysis of accessibility of acid centers within porous solid particles, comprising the steps of:
s1, preparing an alkaline probe molecular solution by adopting an organic alkaline compound and a solvent, and putting the alkaline probe molecular solution into a stirring container of an analysis testing system, wherein the analysis testing system can analyze and detect the concentration of the organic solution in real time under an anhydrous condition;
s2, starting a testing system, quickly adding a sample to be tested into the stirring container after a signal to be tested is stable, and continuously monitoring the change of the detection signal in real time;
and S3, obtaining the concentration of the corresponding alkaline probe molecule solution according to the detection signal obtained by real-time monitoring, then calculating the real-time adsorption quantity of the sample to be detected to the alkaline probe molecules, and then drawing by the square root of the real-time adsorption quantity and time to obtain an adsorption rate curve of the alkaline probe molecule solution, wherein the initial slope of the curve is a parameter for judging the accessibility of the acid centers in the sample to be detected, and the adsorption quantity corresponding to the platform of the curve is a parameter for judging the total accessibility of the acid centers in the sample to be detected.
2. The rapid analysis method according to claim 1, wherein the analysis test system comprises: a stirring vessel capable of being isolated from water vapor, an on-line analysis detector for the concentration of an organic solution, a circulating pump, and a pipe fitting for connecting the above components.
3. The rapid analysis method according to claim 1, wherein the stirring container capable of being isolated from water vapor is a container protected by an inert gas atmosphere, and the volume of the container is 50 to 500ml.
4. The rapid analysis method according to claim 1, wherein the organic solution concentration online analysis detector is an ultraviolet or fluorescence detector equipped with an in-situ cell.
5. The rapid assay method according to claim 1, wherein the in-situ cell is a cuvette having a volume of 5 μ l to 1.5ml, preferably 50 μ l to 500 μ l.
6. The rapid analysis method according to claim 1, wherein the circulation pump is a small-volume peristaltic pump or a plunger pump with a smooth flow rate.
7. The rapid analysis method according to claim 1, wherein the basic probe molecules in the basic probe molecule solution comprise a basic organic compound having pyridine nitrogen and amino nitrogen groups, preferably at least one selected from quinoline, acridine and naphthylamine molecules.
8. The rapid analysis method according to claim 1, wherein the solvent in the basic probe molecule solution is a non-polar organic solution, preferably selected from the group consisting of C7-C10 normal or iso-alkanes or their mixtures, C6-C8 aromatic hydrocarbons or their mixtures, carbon tetrachloride, chloroform and CS 2 At least one of (1).
9. The rapid assay method according to claim 1, wherein the concentration of the alkaline probe molecule solution is 10 -9 ～10 -2 mol/L, preferably 10 -7 ～10 -2 mol/L, more preferably 0.1 to 10mmol/L; the sampling amount of the sample to be detected is 0.1-10 g, and preferably 0.5-2 g.
10. The rapid analysis method according to claim 1, wherein the porous solid particles are spherical particle-shaped porous solids having a particle diameter of 5 to 150 μm.
11. The rapid analysis method of claim 1, wherein the porous solid is an FCC catalyst, and the FCC catalyst comprises fresh FCC catalyst, used FCC catalyst, and deactivated FCC catalyst.
12. The rapid analysis method according to claim 1, wherein the porous solid is a porous solid acid catalyst, and the porous solid acid catalyst is subjected to dehydration treatment, preferably, the dehydration treatment temperature is 100-350 ℃.
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