CN113884619A

CN113884619A - Titration method

Info

Publication number: CN113884619A
Application number: CN202111159971.7A
Authority: CN
Inventors: 王宇; 王鹏刚; 梁振兴; 顾鹏
Original assignee: Meishan Boya New Material Co ltd
Current assignee: Meishan Boya New Material Co ltd
Priority date: 2021-09-30
Filing date: 2021-09-30
Publication date: 2022-01-04
Anticipated expiration: 2041-09-30
Also published as: CN118209683A; CN113884619B

Abstract

Embodiments of the present disclosure provide a titration method, which includes: for a first titration process, titrating a precipitant into a metal salt solution at a first titration rate; monitoring a first rate of change of pH of the solution in real time during the first titration; the first pH change rate reaches a preset threshold and the first titration process is stopped. For the Nth titration process, wherein N is more than or equal to 2, determining the Nth titration rate; titrating the precipitant into the solution at an nth titration rate; and in the Nth titration process, monitoring the Nth pH change rate of the solution in real time, wherein the Nth titration rate enables the difference value between the Nth pH change rate and the first pH change rate to be within a preset range.

Description

Titration method

Technical Field

The specification relates to the technical field of powder, in particular to a titration method in a powder preparation process.

Background

Powders are one of the important raw materials in the production of crystals (e.g., scintillating crystals) or ceramics (e.g., scintillating ceramics). The process of preparing the powder (e.g., the titration process) can affect the quality of the powder, further affecting the quality of the crystal or ceramic. Therefore, it is necessary to provide a titration method to improve the quality of the powder.

Disclosure of Invention

One of the embodiments of the present specification provides a titration method, including: for a first titration process, titrating a precipitant into a metal salt solution at a first titration rate; monitoring a first rate of change of pH of the solution in real time during the first titration; stopping the first titration process when the first pH change rate reaches a preset threshold; for the Nth titration process, wherein N is more than or equal to 2, determining the Nth titration rate; titrating the precipitant into solution at the nth titration rate; and in the Nth titration process, monitoring the Nth pH change rate of the solution in real time, wherein the Nth titration rate enables the difference value between the Nth pH change rate and the first pH change rate to be within a preset range.

In some embodiments, the first titration process or the nth titration process is achieved by injecting the precipitant.

In some embodiments, the first titration rate is determined based on at least a concentration of the precipitant, a concentration of the metal salt solution, and a pH of the metal salt solution.

In some embodiments, the nth titration rate is greater than the (N-1) th titration rate.

In some embodiments, the determining the nth titration rate comprises: determining the Nth titration rate based on at least the first pH rate of change and a rate determination model.

In some embodiments, the determining the nth titration rate based on at least the first pH rate of change and rate determination model comprises: determining the Nth titration rate based on the first pH change rate, a titration parameter of the (N-1) th titration process, and the rate determination model.

In some embodiments, the determining the nth titration rate based on at least the first pH rate of change and rate determination model comprises: determining the Nth titration rate based on the first pH change rate, a related parameter, and the rate determination model, wherein the related parameter comprises: at least one of a concentration of the metal salt solution, a concentration of the precipitant, the first titration rate, a pH of the solution at the end of the first titration process, a concentration of the solution at the end of the first titration process, a reaction time of the first titration process, a titration rate of at least one of the second to (N-1) th titration processes, a pH of the solution at the end of at least one of the second to (N-1) th titration processes, a concentration of the solution at the end of at least one of the second to (N-1) th titration processes, or a reaction time of at least one of the second to (N-1) th titration processes.

In some embodiments, the relevant parameter further comprises a reaction temperature.

In some embodiments, the determining the nth titration rate based on at least the first pH rate of change and rate determination model comprises: determining a plurality of candidate titration rates; determining a plurality of candidate pH change rates corresponding to the plurality of candidate titration rates respectively based on at least the plurality of candidate titration rates and the rate determination model; selecting the Nth titration rate from the plurality of candidate titration rates based on the plurality of candidate pH change rates and the first pH change rate.

In some embodiments, the method further comprises: after stopping the first titration process or the Nth titration process, filtering the solution.

Drawings

The present description will be further explained by way of exemplary embodiments, which will be described in detail by way of the accompanying drawings. These embodiments are not intended to be limiting, and in these embodiments like numerals are used to indicate like structures, wherein:

fig. 1 is a flow diagram of an exemplary titration method according to some embodiments.

Fig. 2 is a flow chart illustrating an exemplary determination of an nth titration rate according to some embodiments.

FIG. 3A is a graph of pH as a function of time without adjusting the titration rate during titration.

Fig. 3B is a graphical representation of pH as a function of time during an exemplary titration process, according to some embodiments.

FIG. 4 is a schematic diagram of a titration apparatus according to some embodiments.

Detailed Description

In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings used in the description of the embodiments will be briefly described below. It is obvious that the drawings in the following description are only examples or embodiments of the present description, and that for a person skilled in the art, the present description can also be applied to other similar scenarios on the basis of these drawings without inventive effort. Unless otherwise apparent from the context, or otherwise indicated, like reference numbers in the figures refer to the same structure or operation.

As used in this specification and the appended claims, the terms "a," "an," "the," and/or "the" are not intended to be inclusive in the singular, but rather are intended to be inclusive in the plural, unless the context clearly dictates otherwise. In general, the terms "comprises" and "comprising" merely indicate that steps and elements are included which are explicitly identified, that the steps and elements do not form an exclusive list, and that a method or apparatus may include other steps or elements.

Flow charts are used in this description to illustrate operations performed by a system according to embodiments of the present description. It should be understood that the preceding or following operations are not necessarily performed in the exact order in which they are performed. Rather, the various steps may be processed in reverse order or simultaneously. Meanwhile, other operations may be added to the processes, or a certain step or several steps of operations may be removed from the processes.

Some embodiments of the present disclosure provide a titration method, which may include at least two titration processes, in each titration process, titrating a precipitant into a solution (a solution obtained by a first titration process corresponding to an initial metal salt solution and a subsequent titration process corresponding to a reaction between the precipitant and the metal salt solution) at a specific titration rate, so that a difference between pH change rates of the solutions in any two titration processes is within a preset range, and further, the reaction rate or the precipitation rate of the entire titration process is kept stable, so as to ensure that the quality of a precipitate prepared in each titration process is as consistent as possible, thereby improving the quality of a finally prepared powder. For convenience of description, some contents in this specification are specifically described by taking the preparation of the scintillating powder as an example. The titration method described in the present specification may also be used to prepare other powders, and is not limited to the preparation of scintillating powders.

Fig. 1 is a flow diagram of an exemplary titration method according to some embodiments. In some embodiments, the process 100 may be performed by one or more components of a titration apparatus (e.g., titration apparatus 400). In some embodiments, the process 100 may be performed automatically by a control system. For example, the process 100 may be implemented by control instructions, and the control system controls each component to complete each operation of the process 100 based on the control instructions. In some embodiments, the process 100 may be performed semi-automatically. For example, one or more of the operations of the process 100 may be performed manually by an operator. In some embodiments, one or more additional operations not described may be added and/or one or more operations discussed herein may be deleted upon completion of flow 100. Additionally, the order of the operations shown in FIG. 1 is not intended to be limiting. As shown in fig. 1, the process 100 includes the following steps.

For the first titration process, the precipitant is titrated into the metal salt solution at a first titration rate, step 110.

In some embodiments, the metal salt solution can be obtained by dissolving a metal oxide and/or a metal salt (e.g., a metal oxide or a metal salt used to prepare the scintillation powder) in an acid solution. In some embodiments, the acid solution may include at least one of nitric acid, sulfuric acid, or hydrochloric acid. In some embodiments, the mass of the metal oxide and/or metal salt may be calculated based on the mass of the powder to be produced.

Taking the preparation of the GAGG scintillating powder as an example, the metal oxide may include gallium oxide, gadolinium oxide, and aluminum oxide. The metal salt may include gallium salts (e.g., gallium nitrate, gallium sulfate, gallium chloride, etc.), gadolinium salts (e.g., gadolinium nitrate, gadolinium sulfate, gadolinium chloride, etc.), aluminum salts (e.g., aluminum nitrate, aluminum sulfate, aluminum chloride, aluminum ammonium sulfate, etc.), and the like.

In some embodiments, the pH of the metal salt solution is related to the nature of the metal oxide (or metal salt) and the acid (e.g., strong acid, weak acid). In some embodiments, the pH of the metal salt solution can be less than 7, equal to 7, or greater than 7.

In some embodiments, the amount of acid solution may be in slight excess to allow sufficient dissolution of the metal oxide. In some embodiments, the pH of the metal salt solution can be in the range of 4-6. In some embodiments, the pH of the metal salt solution may be in the range of 4.2-5.8. In some embodiments, the pH of the metal salt solution may be in the range of 4.4-5.6. In some embodiments, the pH of the metal salt solution may be in the range of 4.6-5.4. In some embodiments, the pH of the metal salt solution may be in the range of 4.8-5.2.

In some embodiments, the type of precipitant may be determined based on the pH of the metal salt solution. In some embodiments, the precipitating agent may comprise a strongly basic solution and/or a weakly basic solution. In some embodiments, the precipitating agent may include sodium hydroxide, ammonia, ammonium bicarbonate, and the like. In some embodiments, the precipitating agent may be a single precipitating agent or a mixed precipitating agent. For example, the precipitant may be a mixed solution of ammonia and ammonium bicarbonate.

In some embodiments, the concentration of the precipitating agent may be determined based on the concentration of the metal salt solution and the pH of the metal salt solution.

In some embodiments, the concentration of the metal salt solution, the concentration of the acid, and the concentration of the precipitating agent may be determined from empirical parameters. In some embodiments, the concentration of the metal salt solution, the concentration of the acid, and the concentration of the precipitating agent may also be determined by other means. E.g., by user customization, statistical data, etc.

The titration rate may refer to the volume or mass of precipitant added to the metal salt solution per unit time (e.g., 1 second, 1 minute) during the titration. Accordingly, the first titration rate may refer to the volume or mass of the precipitant added to the metal salt solution per unit time during the first titration. In some embodiments, the titration rate of the precipitating agent into the metal salt solution may be controlled and detected by a flow meter (e.g., an ultrasonic flow meter, an electromagnetic flow meter).

In some embodiments, the first titration rate may be determined in a variety of ways.

In some embodiments, the first titration rate may be determined based on a concentration of the precipitant, a concentration of the metal salt solution, and a pH of the metal salt solution. Taking preparation of the GAGG scintillation powder as an example, the concentration of ammonia water as a precipitator is 3mol/L, the concentration of a metal salt solution is 0.3mol/L, and when the pH value of the metal salt solution is less than 7, the first drop rate can be within the range of 8mL/min to 12 mL/min; the first titration rate may be in the range of 4mL/min to 6mL/min when the pH of the metal salt solution is in the range of 7 to 8.

In some embodiments, the first titration rate may also be determined by other means (e.g., empirical parameters, statistical data, user customization, etc.).

In the initial stage of titration, because the concentration of the metal salt solution is relatively high, if the first titration rate is too high, the precipitant and the metal salt solution may form crystal nuclei due to the phenomenon of "local over-concentration", and the crystal nuclei may affect the quality of the precipitate, thereby reducing the quality of the powder. In the examples of the present specification, the nucleation rate may be referred to as a nucleation rate. In some embodiments, the first titration rate may be less than the nucleation titration rate to avoid nucleation during the titration process, which may affect the quality of the precipitate.

In a first titration process, a first rate of change of pH of the solution is monitored in real time, step 120.

The rate of change of pH may refer to the amount of change in the pH of the solution per unit time. Accordingly, the first pH change rate may refer to the amount of change in the pH of the solution per unit time during the first titration. In some embodiments, the pH of the solution may be monitored by a pH sensor in real time, so as to obtain the change of pH with time (e.g., a pH change with time curve as shown in fig. 3A and 3B, wherein the slope of the curve corresponding to each time is the instantaneous pH change rate at the corresponding time).

The precipitant is titrated into the metal salt solution, and reacts with the metal ions to generate precipitates on one hand, and reacts with the hydrogen ions contained in the excessive acid to generate neutralization reaction on the other hand. Thus, the rate of change in pH may reflect the rate of the precipitation reaction.

The first pH change rate reaches a preset threshold and the first titration process is stopped, step 130.

In the initial stage of titration, the overall reaction is relatively fast after the precipitant is added, due to the relatively large concentration of the metal salt solution. Accordingly, the rate of change of the pH of the solution gradually increases (or remains substantially stable). With the continuous addition of the precipitant, the metal ions in the solution continuously react with the precipitant to precipitate. On the one hand, the formed precipitate influences the continuation of the titration reaction, and on the other hand, the gradual reduction of the concentration of the metal ions in the solution leads to the reduction of the precipitation reaction rate. Accordingly, the rate of change of pH of the solution may begin to decrease after a certain threshold is reached. For example, as shown in FIG. 3A, the slope of the curve gradually increases (or remains substantially constant) from the origin to time tm, and the slope of the curve begins to decrease from time tm. Therefore, when the first pH change rate reaches a preset threshold (e.g., the pH change rate corresponding to the time tm shown in fig. 3A or a pH change rate threshold set according to the process requirement (e.g., the pH change rate corresponding to the time tm)), it is necessary to stop the first titration process in time and determine and/or adjust the titration rates of the subsequent titration processes so that the pH change rates of each titration process are equivalent to ensure that the quality of the precipitates is consistent.

In some embodiments, the preset threshold may correspond to a turning point (a turning point from increasing or substantially stabilizing to decreasing) of the rate of change of the pH of the solution. In some embodiments, the predetermined threshold may be set according to process requirements. In some embodiments, the preset threshold may be determined by empirical parameters, statistical data, user customization, and the like.

In some embodiments, after stopping the first titration process, the solution may be further filtered to obtain a precipitate generated by the first titration process, and the subsequent titration process may be continued on the filtered solution.

In step 140, for the Nth titration process (where N ≧ 2), the Nth titration rate is determined.

In connection with step 110, the nth titration rate may refer to the volume or mass of precipitant added to the metal salt solution per unit time during the nth titration.

At step 150, the precipitant is titrated into solution at the nth titration rate.

In some embodiments, after the nth titration rate is determined, the precipitant can be titrated into the solution at the nth titration rate. For the precipitant and the related contents of titrating the precipitant into the solution, reference may be made to the description related to step 110 of this specification, and details are not repeated here.

And step 160, monitoring the Nth pH change rate of the solution in real time in the Nth titration process, wherein the Nth titration rate enables the difference value between the Nth pH change rate and the first pH change rate to be within a preset range.

In some embodiments, the nth titration rate may be determined based at least on the first pH rate of change and the rate determination model.

In some embodiments, the rate determination model may include a statistical model, an empirical model, a model determined by modeling, a model determined by data fitting, and the like.

In some embodiments, the rate determination model may comprise a machine learning model.

In some embodiments, the nth titration rate may also be determined based on the first pH rate of change, the titration parameters and the rate determination model for the (N-1) th titration process to achieve continuous control of the entire titration process.

In some embodiments, the titration parameters of the (N-1) th titration process may include, but are not limited to, the (N-1) th titration rate, the (N-1) th pH change rate, the reaction time of the (N-1) th titration process, the pH of the solution at the end of the (N-1) th titration process, the concentration of the solution at the end of the (N-1) th titration process, and the like.

In some embodiments, the nth titration rate may also be determined based on the first pH rate of change, the related parameter, and the rate determination model to improve the accuracy and overall suitability of the nth titration rate.

In some embodiments, the relevant parameters may include a concentration of the metal salt solution, a concentration of the precipitant, a first titration rate, a pH of the solution at the end of the first titration process, a concentration of the solution at the end of the first titration process, a reaction time of the first titration process, a titration rate of at least one of the second to (N-1) th titration processes, a pH of the solution at the end of at least one of the second to (N-1) th titration processes, a concentration of the solution at the end of at least one of the second to (N-1) th titration processes, a reaction time of at least one of the second to (N-1) th titration processes, a concentration of the solution corresponding to any time during the entire titration process, a pH of the solution corresponding to any time during the entire titration process, or the like or any combination thereof.

In some embodiments, the relevant parameter may also include the reaction temperature. In some embodiments, the reaction temperature may include an average reaction temperature for each titration process, a corresponding instantaneous temperature at each time, and the like.

In some embodiments, the relevant parameters may also include other parameters related to the titration process, such as reaction humidity, air index, and the like.

In some embodiments, the model may be determined by a plurality of sample training rates. For convenience of description, the metal salt solution and the precipitant involved in the model training process are respectively referred to as "sample metal salt solution" and "sample precipitant", and the parameters involved in the model training process are referred to as "sample parameters". In some embodiments, during the model training process, the input of the model may include any combination of any one or more of the sample parameters corresponding to the above parameters and the sample candidate titration rate; the output of the model may be a sample pH rate of change of the sample solution; the training label (model-trained label) is the actual pH change rate of the sample solution.

Accordingly, after model training is completed, the rate determination model may output solution pH change rates corresponding to a plurality of candidate titration rates based on the multidimensional correlation parameter associated with the metal salt solution. Further, a final nth titration rate may be screened from the plurality of candidate titration rates based on the pH change rates and the first pH change rate corresponding to the plurality of candidate titration rates.

In some embodiments, the parameters of the rate determination model may also be dynamically updated based on updated experimental data, improving the comprehensive learning capabilities of the rate determination model to determine a more appropriate nth titration rate.

For a description of determining the nth titration rate based on at least the first pH change rate and the rate determination model, reference may be made to other parts of the description (e.g., fig. 2 and its associated description) and further description thereof is omitted here.

In some embodiments, the difference between the nth pH rate of change and the first pH rate of change may refer to a difference between an average pH rate of change of the nth titration procedure and an average pH rate of change of the first titration procedure. For example, as shown in fig. 3B, the difference between the second rate of pH change and the first rate of pH change may be the difference between the average rate of pH change for the second titration process and the average rate of pH change for the first titration process: AB/(t2-t1) -OA/t 1.

In some embodiments, the difference between the nth pH rate of change and the first pH rate of change may refer to a difference between an instantaneous NpH th rate of change at a time during the nth titration and an instantaneous first pH rate of change at a time during the first titration (a time corresponding to a time during the nth titration). In some embodiments, assuming that the reaction time of the first titration process and the reaction time of the nth titration process are T1 and Tn, respectively, the X-th time in the first titration process corresponds to the (XTn/T1) th time in the nth titration process, wherein X is not greater than any value of T1. For example, if the reaction time of the first titration process is 10 minutes and the reaction time of the nth titration process is 5 minutes, the 4 th minute in the first titration process corresponds to the 2 nd minute in the nth titration process.

In some embodiments, the nth pH rate of change may reflect the reaction rate of the nth titration process. And controlling the Nth titration rate to enable the difference value between the Nth pH change rate and the first pH change rate to be within a preset range, so that the reaction rate of the Nth titration process can be close to that of the first titration process, and the precipitation reaction rate in each titration process is further kept stable, so that the quality of the finally prepared powder is improved.

In some embodiments, the predetermined range may be determined by empirical parameters, statistical data, user customization, and the like.

In some embodiments, the titration rate during the same titration may be a fixed value or may be dynamically varied. For example, the nth titration rate may be dynamically adjusted such that the difference between the nth pH change rate and the first pH change rate is within a preset range.

Along with the continuous addition of the precipitant, the metal ions in the solution continuously react with the precipitant to precipitate, and the concentration of the metal ions in the solution is gradually reduced. Therefore, in some embodiments, the nth titration rate may be greater than the (N-1) th titration rate, so that the reaction rate of the metal ions and the precipitant is kept as stable as possible during each titration without generating crystal nuclei, thereby reducing quality problems such as uneven particle size of the powder. For example, in the first titration process, the concentration of metal ions in the metal salt solution is the greatest, and the first titration rate may be the smallest to prevent the "local over-concentration" phenomenon from nucleating. When entering the second titration process, a second titration rate, which is greater than the first titration rate, may be used due to the reduced concentration of metal ions in the solution. When entering the third titration process, the third titration rate may be greater than the second titration rate as the concentration of metal ions in the solution further decreases, and so on.

In some embodiments, similar to the first titration process, when the (N-1) th pH change rate reaches a preset threshold, the (N-1) th titration process may be stopped and the solution filtered to obtain a precipitate generated by the (N-1) th titration process, and the N titration process may be continued on the filtered solution. In some embodiments, the preset threshold values for the pH change rates for different titration processes may be the same or different. For example only, as shown in fig. 3B, at point a, the first pH change rate reaches a preset threshold, the first titration process (e.g., the curve of section OA shown in fig. 3) ends, and the second titration process is entered. At point B, the second pH change rate reaches a predetermined threshold, the second titration process (shown as the AB plot in fig. 3) ends, and a third titration process is performed. The pH change rate shown at point a and the pH change rate shown at point B may be the same or different.

In some embodiments, the first titration process or the nth titration process may be implemented by spraying a precipitant to contact and react the precipitant with the metal salt solution in the form of droplets, so that the reaction surface area may be increased and the reaction efficiency may be improved.

In some embodiments, during the titration, the solution may be stirred to mix the precipitating agent with the metal ions sufficiently to facilitate the precipitation reaction. In some embodiments, the solution may be stirred in a fixed direction. In some embodiments, the direction of agitation may be changed periodically, for example, clockwise followed by counterclockwise. Periodically changing the direction of agitation can improve the mixing effect and promote the precipitation reaction.

In some embodiments, the agitation rate for different titration processes may be the same or different. For example, during the first titration, the solution may be stirred at a greater stirring speed. During the nth titration, the solution may be stirred at a slower stirring speed.

In some embodiments, after stopping the nth titration process, the solution may be filtered to collect a precipitate resulting from the nth titration process. In some embodiments, the precipitates collected from each titration process may be pooled and further processed (e.g., dried, milled, etc.) to produce the final powder.

It should be noted that the above description of the process 100 is for illustration and description only, and does not limit the scope of the application of the present disclosure. Various modifications and alterations to process 100 will become apparent to those skilled in the art in light of the present description. However, such modifications and variations are intended to be within the scope of the present description. For example, during each titration period, a parameter other than pH (e.g., the concentration of the metal ion) may be monitored so that the rate of decrease in the concentration of the metal ion during each titration period is comparable to ensure that the rate of reaction during each titration period is stable. The other parameters in the examples of the present specification are not limited as long as they reflect the reaction rate of the titration process.

Fig. 2 is a flow chart illustrating an exemplary determination of an nth titration rate according to some embodiments. In some embodiments, the process 200 may be performed by a processing device of a control system. As shown in fig. 2, the process 200 includes the following steps.

At step 210, a plurality of candidate titration rates are determined.

In some embodiments, the candidate titration rates may be determined by statistical data, empirical parameters, or user customization. In some embodiments, the candidate titration rates may be determined based on the (N-1) th titration rate. For example, the candidate titration rate may be greater than the (N-1) th titration rate, and the difference between the two is within a preset range. In some embodiments, the preset range may be determined based on statistical data, empirical parameters, or user customization.

In some embodiments, the plurality of candidate titration rates may be arranged in an arithmetic progression. For example, the plurality of candidate titration rates may be 5ml/min, 10ml/min, 15ml/min, 20ml/min, and the like. In some embodiments, the plurality of candidate titration rates may be arranged in an arithmetic progression of numerical increments or decrements. For example, 5ml/min, 6ml/min, 8ml/min, 11ml/min, 15ml/min, etc. The number of candidate titration rates may not be limited in the embodiments of the present specification. In some embodiments, the number of candidate titration rates may be increased as appropriate in order to obtain a more appropriate nth titration rate.

Step 220, determining a plurality of candidate pH change rates corresponding to the plurality of candidate titration rates, respectively, based on at least the plurality of candidate titration rates and the rate determination model.

In some embodiments, as described in connection with fig. 1, a plurality of candidate titration rates and one or more associated parameters may be input to a rate determination model that outputs a plurality of candidate pH change rates corresponding to the plurality of candidate titration rates, respectively. For a particular candidate titration rate, the candidate pH change rate may represent a simulated change in pH of the solution based on the particular candidate titration rate.

An nth titration rate is selected from the plurality of candidate titration rates based on the plurality of candidate pH change rates and the first pH change rate, step 230.

In some embodiments, the difference between the plurality of candidate pH change rates and the first pH change rate may be calculated, respectively, and it may be determined whether the minimum difference is within a preset range. If yes, determining the candidate titration rate corresponding to the minimum difference value as the Nth titration rate. If not, further multiple other candidate titration rates are determined and the above steps are repeated.

In some embodiments, the next set of candidate titration rates may be adjusted based on the minimum difference. For example, if the minimum difference corresponding to the previous set of candidate titration rates still deviates from the preset range to a large extent, the next set of input candidate titration rates may be adjusted to a larger extent. For another example, if the minimum difference corresponding to the previous set of candidate titration rates is slightly different from the preset range, the next set of input candidate titration rates may be adjusted with a small amplitude.

It should be noted that the above description related to the flow 200 is only for illustration and description, and does not limit the applicable scope of the present specification. Various modifications and alterations to flow 200 will be apparent to those skilled in the art in light of this description. However, such modifications and variations are intended to be within the scope of the present description.

FIG. 3A is a graph of pH as a function of time without adjusting the titration rate during titration. Figure 3B is a schematic of a graph of pH versus time with titration rates adjusted during titration according to some embodiments of the present description.

As shown in FIG. 3A, the same titration rate is maintained throughout the titration, the slope of the curve remains substantially constant first, and the slope of the curve begins to decrease from time tm.

As shown in fig. 3B, according to some embodiments of the present disclosure, the titration rates of different titration processes are dynamically adjusted during the whole titration process, such that the slope of the curve corresponding to each titration process at a corresponding specific time (e.g., the xth time in the first titration process corresponds to the XTn/T1 time in the nth titration process) is comparable, and further, the reaction rate of the whole titration process can be kept stable.

As shown in fig. 4, the titration apparatus 400 may include at least two titration assemblies (illustrated as two titration assemblies, a first titration assembly 410 and an nth titration assembly 420, respectively, where N is an integer no less than 2) and a collection assembly 430.

The first titration assembly 410 may be used to perform a first titration process. In some embodiments, the first titration assembly 410 may include a first titration vessel 411 and a first titration head 412.

In some embodiments, the first titration vessel 411 may be a vessel containing a metal salt solution, and may also provide a location where the precipitant and the metal salt solution undergo the first titration reaction. In some embodiments, the material of the first dropping container 411 may include any material that does not react with the metal salt solution and the precipitating agent.

In some embodiments, a first titration showerhead 412 may be used to inject a precipitant into the first titration vessel 411. In some embodiments, the first titration showerhead 412 may be positioned above the metal salt solution and within or above the first titration vessel 411.

In some embodiments, the first titration assembly 410 may further comprise a first metal salt solution input tube 413 for inputting a metal salt solution into the first titration container 411.

Nth titration component 420 may be configured to perform an nth titration procedure. In some embodiments, nth titration assembly 420 may include an nth titration vessel 421, a saline delivery tube 422, and an nth titration showerhead 423.

In some embodiments, the nth titration vessel 421 may be the same or different from the first titration vessel 411. In some embodiments, the nth titration vessel 421 may be used to contain a salt solution and may also provide a location for the precipitant to perform the nth titration reaction with the salt solution.

In some embodiments, saline delivery tube 422 may be used to input saline after the (N-1) th titration process is completed to Nth titration component 420.

In some embodiments, nth titration showerhead 423 may be the same as or different from first titration showerhead 412. In some embodiments, nth titration spray head 423 may be used to spray a precipitant into nth titration vessel 421. In some embodiments, the nth titration showerhead 423 may be positioned above the saline solution.

In some embodiments, the Nth titration component 420 can further include an Nth filter 424 for filtering the salt solution produced by the (N-1) th titration process to collect the precipitate produced by the (N-1) th titration process.

The collection assembly 430 can be used to filter and collect the precipitate resulting from the nth titration procedure. In some embodiments, collection assembly 430 may include a collection container 431, a collection line 432, and a collection filter 433.

In some embodiments, collection container 431 can be used to hold the filtrate resulting from the filtration of the saline solution of the nth titration procedure. In some embodiments, the collection container 431 can be the same or different from the first titration container 411.

In some embodiments, the collection line 432 may be used to input the saline solution after the nth titration process is complete to the collection assembly 430.

In some embodiments, the collection filter 433 may be used to filter the salt solution produced by the nth titration process to collect the precipitate produced by the nth titration process.

In some embodiments, at least one of the at least two titration assemblies may further comprise an agitation member (not shown) for agitating the salt solution to substantially react the precipitant with the metal ion.

In some embodiments, the titration apparatus 400 may further include a pH sensor (not shown) for monitoring the pH of the saline solution.

In some embodiments, the titration apparatus 400 may further include a processing device for generating a time-dependent change in pH of the saline solution (e.g., a rate of change in pH) based on the pH of the saline solution detected by the pH sensor. In some embodiments, the processing device may also determine an nth titration rate. In some embodiments, the processing device may also determine a rate determination model. For the description of determining the nth titration rate and determining the rate determination model, reference may be made to other parts of the present specification (for example, fig. 1, fig. 2 and the related description thereof), and details thereof are not repeated herein.

The beneficial effects that may be brought by the embodiments of the present description include, but are not limited to: (1) the method comprises at least two titration processes, wherein each titration process titrates a precipitator into a salt solution at a specific titration rate, so that the difference value of the pH change rates of the solutions in any two titration processes in the at least two titration processes is within a preset range, the reaction rate of the whole titration process can be kept stable, the quality of precipitates prepared in each titration process is ensured to be consistent as much as possible, and the quality of finally prepared powder is improved. (2) Through a rate determination model, multidimensional parameters are integrated, and pH change conditions under different titration rates are simulated, so that the Nth titration rate is determined, and the Nth titration rate can be more appropriate and accurate.

Having thus described the basic concept, it will be apparent to those skilled in the art that the foregoing detailed disclosure is to be regarded as illustrative only and not as limiting the present specification. Various modifications, improvements and adaptations to the present description may occur to those skilled in the art, although not explicitly described herein. Such modifications, improvements and adaptations are proposed in the present specification and thus fall within the spirit and scope of the exemplary embodiments of the present specification.

Also, the description uses specific words to describe embodiments of the description. Reference throughout this specification to "one embodiment," "an embodiment," and/or "some embodiments" means that a particular feature, structure, or characteristic described in connection with at least one embodiment of the specification is included. Therefore, it is emphasized and should be appreciated that two or more references to "an embodiment" or "one embodiment" or "an alternative embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, some features, structures, or characteristics of one or more embodiments of the specification may be combined as appropriate.

Additionally, the order in which the elements and sequences of the process are recited in the specification, the use of alphanumeric characters, or other designations, is not intended to limit the order in which the processes and methods of the specification occur, unless otherwise specified in the claims. While various presently contemplated embodiments of the invention have been discussed in the foregoing disclosure by way of example, it is to be understood that such detail is solely for that purpose and that the appended claims are not limited to the disclosed embodiments, but, on the contrary, are intended to cover all modifications and equivalent arrangements that are within the spirit and scope of the embodiments herein. For example, although the system components described above may be implemented by hardware devices, they may also be implemented by software-only solutions, such as installing the described system on an existing server or mobile device.

Similarly, it should be noted that in the preceding description of embodiments of the present specification, various features are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure aiding in the understanding of one or more of the embodiments. This method of disclosure, however, is not intended to imply that more features than are expressly recited in a claim. Indeed, the embodiments may be characterized as having less than all of the features of a single embodiment disclosed above.

Numerals describing the number of components, attributes, etc. are used in some embodiments, it being understood that such numerals used in the description of the embodiments are modified in some instances by the use of the modifier "about", "approximately" or "substantially". Unless otherwise indicated, "about", "approximately" or "substantially" indicates that the number allows a variation of ± 20%. Accordingly, in some embodiments, the numerical parameters used in the specification and claims are approximations that may vary depending upon the desired properties of the individual embodiments. In some embodiments, the numerical parameter should take into account the specified significant digits and employ a general digit preserving approach. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the range are approximations, in the specific examples, such numerical values are set forth as precisely as possible within the scope of the application.

For each patent, patent application publication, and other material, such as articles, books, specifications, publications, documents, etc., cited in this specification, the entire contents of each are hereby incorporated by reference into this specification. Except where the application history document does not conform to or conflict with the contents of the present specification, it is to be understood that the application history document, as used herein in the present specification or appended claims, is intended to define the broadest scope of the present specification (whether presently or later in the specification) rather than the broadest scope of the present specification. It is to be understood that the descriptions, definitions and/or uses of terms in the accompanying materials of this specification shall control if they are inconsistent or contrary to the descriptions and/or uses of terms in this specification.

Finally, it should be understood that the embodiments described herein are merely illustrative of the principles of the embodiments of the present disclosure. Other variations are also possible within the scope of the present description. Thus, by way of example, and not limitation, alternative configurations of the embodiments of the specification can be considered consistent with the teachings of the specification. Accordingly, the embodiments of the present description are not limited to only those embodiments explicitly described and depicted herein.

Claims

1. A titration method, characterized in that it comprises:

for the first titration period of time it is preferred,

titrating the precipitant into the metal salt solution at a first titration rate;

monitoring a first rate of change of pH of the solution in real time during the first titration;

stopping the first titration process when the first pH change rate reaches a preset threshold;

for the Nth titration process, where N.gtoreq.2,

determining an Nth titration rate;

titrating the precipitant into solution at the nth titration rate;

and in the Nth titration process, monitoring the Nth pH change rate of the solution in real time, wherein the Nth titration rate enables the difference value between the Nth pH change rate and the first pH change rate to be within a preset range.

2. The titration method according to claim 1, wherein the first titration process or the Nth titration process is achieved by means of injecting the precipitant.

3. The titration method according to claim 1, wherein the first titration rate is determined based on at least a concentration of the precipitant, a concentration of the metal salt solution, and a pH of the metal salt solution.

4. The titration method according to claim 1, wherein the nth titration rate is greater than the (N-1) th titration rate.

5. The titration method according to claim 1, wherein said determining an nth titration rate comprises:

determining the Nth titration rate based on at least the first pH rate of change and a rate determination model.

6. The titration method according to claim 5, wherein said determining the Nth titration rate based on at least the first pH rate of change and rate determination model comprises:

determining the Nth titration rate based on the first pH change rate, a titration parameter of the (N-1) th titration process, and the rate determination model.

7. The titration method according to claim 5, wherein said determining the Nth titration rate based on at least the first pH rate of change and rate determination model comprises:

determining the Nth titration rate based on the first pH change rate, a related parameter, and the rate determination model, wherein the related parameter comprises:

at least one of a concentration of the metal salt solution, a concentration of the precipitant, the first titration rate, a pH of the solution at the end of the first titration process, a concentration of the solution at the end of the first titration process, a reaction time of the first titration process, a titration rate of at least one of the second to (N-1) th titration processes, a pH of the solution at the end of at least one of the second to (N-1) th titration processes, a concentration of the solution at the end of at least one of the second to (N-1) th titration processes, or a reaction time of at least one of the second to (N-1) th titration processes.

8. The titration method according to claim 8, wherein the relevant parameter further comprises a reaction temperature.

9. The titration method according to claim 5, wherein said determining the Nth titration rate based on at least the first pH rate of change and rate determination model comprises:

determining a plurality of candidate titration rates;

determining a plurality of candidate pH change rates corresponding to the plurality of candidate titration rates respectively based on at least the plurality of candidate titration rates and the rate determination model;

selecting the Nth titration rate from the plurality of candidate titration rates based on the plurality of candidate pH change rates and the first pH change rate.

10. The titration method according to claim 1, wherein the method further comprises:

after stopping the first titration process or the Nth titration process, filtering the solution.