Simple determination method for effective components of ionic liquid for desulfurization

Abstract

The invention discloses a simple determination method for effective components of an ionic liquid for desulfurization, belongs to the technical field of ionic liquid application, and aims to solve the problems of complex instruments, long time consumption and high cost of a traditional determination method. The method comprises the following steps: S1, dissolving 2ml of an ionic liquid sample into 40ml of deionized water to prepare a mixed solution to be detected; s2, heating the liquid to be detected at 105 DEG C for 30 minutes; s3, supplementing deionized water to the volume before heating; s4, titrating with 0.5 mol / L hydrochloric acid until the pH value is 2.32, recording the consumption, titrating with 0.5 mol / L sodium hydroxide until the pH value is 10, and recording the consumption; and S5, calculating the mass concentration of the effective component according to a formula C% = 0.09 * cNaOH * VNaOH / Vsample. The method only needs basic instruments, consumes less time, is low in cost, is suitable for quaternary ammonium salt and imidazole desulfurization ionic liquids, has a detection repeatability error of less than or equal to 1.2% and a standard recovery rate of 98.5-102.3%, can efficiently provide data support for desulfurization process parameter adjustment and ionic liquid regeneration efficiency evaluation, and is suitable for daily quality monitoring of industrial sites.

Description

Technical Field

[0001] This invention relates to the field of ionic liquid application technology, specifically a simplified method for determining the effective components of ionic liquids used in desulfurization. Background Technology

[0002] In desulfurization processes, ionic liquids are widely used due to their unique properties. However, accurate determination of the effective components in ionic liquids is crucial for ensuring desulfurization efficiency and process optimization. Currently, traditional determination methods have some shortcomings. For example, some methods require complex instruments and equipment, are cumbersome to operate, and are costly; others are time-consuming, failing to meet the rapid detection needs of actual production; furthermore, the accuracy and repeatability of some methods need improvement, making it difficult to accurately reflect the true content of the effective components in the ionic liquid. These problems have brought certain challenges to the application and management of ionic liquids in the desulfurization field. This paper will propose a series of optimization measures to address these issues, improving the efficiency and reliability of effective component determination in ionic liquids and supporting their promotion in industrial desulfurization applications. Summary of the Invention

[0003] The purpose of this invention is to solve the above problems and provide a simple method for determining the effective components of ionic liquids used for desulfurization.

[0004] The specific solution of this invention is: a simplified method for determining the effective components of ionic liquids used in desulfurization, comprising the following steps:

[0005] S1 Sample preparation: Dissolve the ionic liquid sample in deionized water to obtain the mixed solution to be tested;

[0006] S2 Heating treatment: The mixed solution to be tested is heated at a set temperature for a set duration;

[0007] S3 Volume replenishment: After heating is complete, add deionized water to the volume of the mixed solution to be tested as stated before heating;

[0008] S4 Acid-Base Titration: First, titrate with a hydrochloric acid solution of a set concentration until the pH of the mixed solution reaches the first set value, and record the volume of hydrochloric acid solution consumed; then titrate with a sodium hydroxide solution of a set concentration until the pH of the mixed solution reaches the second set value, and record the volume of sodium hydroxide solution consumed.

[0009] S5 Result Calculation: Based on the recorded volume of sodium hydroxide solution consumed, the concentration of sodium hydroxide solution, and the volume of the ionic liquid sample, the mass concentration of the effective component in the ionic liquid is calculated using the calculation formula.

[0010] The detection of the active ingredient is based on the pH buffering effect formed by the absorption characteristics of the active ingredient in the ionic liquid on SO2. This buffering effect is released by heating and hydrochloric acid, and then the buffering effect is determined by titration with sodium hydroxide, thereby realizing the calculation of the concentration of the active ingredient.

[0011] Furthermore, in S1, 2 ml of the ionic liquid sample is dissolved in 40 ml of deionized water.

[0012] Furthermore, in S2, the set temperature is 105°C and the set duration is 30 minutes.

[0013] Furthermore, in S4, the concentration of the hydrochloric acid solution is 0.5 mol / L, and the first set pH value is 2.32; the concentration of the sodium hydroxide solution is 0.5 mol / L, and the second set pH value is 10.

[0014] Furthermore, in S5, the calculation formula is: C% = 0.09 × cNaOH × VNaOH / Vsample, where C% is the mass concentration of the effective component of the ionic liquid, cNaOH is the concentration of the sodium hydroxide solution, VNaOH is the volume of sodium hydroxide solution consumed, and Vsample is the volume of the ionic liquid sample.

[0015] Furthermore, the ionic liquid is a quaternary ammonium salt desulfurization ionic liquid or an imidazole desulfurization ionic liquid.

[0016] The present invention has the following beneficial effects:

[0017] 1. Ease of operation and equipment versatility

[0018] This assay method employs common acid-base titration procedures, requiring only basic laboratory equipment such as burettes, beakers, and heating devices. It eliminates the need for large, sophisticated equipment like high-performance liquid chromatography (HPLC) and mass spectrometry (MS), significantly lowering the barrier to entry. Even non-professional testing personnel can quickly master the operating procedures with simple training. It is particularly suitable for daily quality monitoring in desulfurization industrial settings, avoiding the operational barriers caused by the complexity of equipment in traditional methods.

[0019] 2. Dual optimization of cost and efficiency

[0020] The heating process at 105℃ takes only 30 minutes, and the acid-base titration process takes no more than 15 minutes per cycle. The entire process, from sample preparation to result calculation, can be completed within one hour, reducing the time by more than 60% compared to traditional spectroscopic analysis methods. Furthermore, only common chemicals such as hydrochloric acid and sodium hydroxide are used as reagents, keeping the cost per sample below 5 yuan, reducing consumable costs by more than 80% compared to traditional methods. This makes it particularly suitable for batch testing of ionic liquids in large-scale industrial production, effectively improving the real-time control efficiency of desulfurization processes.

[0021] 3. Accuracy and reliability assurance

[0022] A titration system was designed utilizing the pH buffering properties of the active ingredient in the ionic liquid for SO2 absorption. Heating at 105℃ simulated desulfurization conditions, making the sample pretreatment process more closely resemble real-world applications. Experimental data showed that the repeatability error for thiosulfate detection using this method was ≤1.2%, with spiked recoveries ranging from 98.5% to 102.3%, representing a 15% improvement in accuracy compared to traditional potentiometric titration. The calculation formula C% = 0.09 × cNaOH × VNaOH / Vsample directly correlates the titration volume with the concentration of the active ingredient, avoiding complex instrument parameter calibration and ensuring industrial-grade reliability of the detection results.

[0023] 4. Process adaptability and application scalability

[0024] This method is specifically designed for the characteristics of the effective components in desulfurization ionic liquids. The combined heating-titration process eliminates interference from volatile impurities in the sample and accurately captures the chemical behavior of the effective components through a pH buffer. Testing has shown that this method is applicable to various desulfurization ionic liquid systems, including quaternary ammonium salts and imidazoles, and can accurately determine the effective component concentration in samples ranging from 5% to 30%. It can directly provide data support for adjusting desulfurization tower operating parameters and evaluating ionic liquid regeneration efficiency, promoting the development of desulfurization processes towards lower cost and higher efficiency. Detailed Implementation

[0025] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0026] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0027] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the meaning of "and / or" throughout the text includes three parallel solutions; for example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0028] A specific embodiment of a simplified method for determining the effective components of ionic liquids used in desulfurization includes the following steps:

[0029] S1 Sample preparation: Dissolve the ionic liquid sample in deionized water to obtain the mixed solution to be tested;

[0030] S2 Heating treatment: The mixed solution to be tested is heated at a set temperature for a set duration;

[0031] S3 Volume replenishment: After heating is complete, add deionized water to the volume of the mixed solution to be tested as stated before heating;

[0032] S4 Acid-Base Titration: First, titrate with a hydrochloric acid solution of a set concentration until the pH of the mixed solution reaches the first set value, and record the volume of hydrochloric acid solution consumed; then titrate with a sodium hydroxide solution of a set concentration until the pH of the mixed solution reaches the second set value, and record the volume of sodium hydroxide solution consumed.

[0033] S5 Result Calculation: Based on the recorded volume of sodium hydroxide solution consumed, the concentration of sodium hydroxide solution, and the volume of the ionic liquid sample, the mass concentration of the effective component in the ionic liquid is calculated using the calculation formula.

[0034] The detection of the active ingredient is based on the pH buffering effect formed by the absorption characteristics of the active ingredient in the ionic liquid on SO2. This buffering effect is released by heating and hydrochloric acid, and then the buffering effect is determined by titration with sodium hydroxide, thereby realizing the calculation of the concentration of the active ingredient.

[0035] In this embodiment, in step S1, 2 ml of ionic liquid sample is dissolved in 40 ml of deionized water.

[0036] In this embodiment, in S2, the set temperature is 105°C and the set duration is 30 minutes.

[0037] In this embodiment, in step S4, the concentration of the hydrochloric acid solution is 0.5 mol / L, and the first set pH value is 2.32; the concentration of the sodium hydroxide solution is 0.5 mol / L, and the second set pH value is 10.

[0038] In this embodiment, in S5, the calculation formula is: C% = 0.09 × cNaOH × VNaOH / Vsample, where C% is the mass concentration of the effective component of the ionic liquid, cNaOH is the concentration of the sodium hydroxide solution, VNaOH is the volume of sodium hydroxide solution consumed, and Vsample is the volume of the ionic liquid sample.

[0039] In this embodiment, the ionic liquid is a quaternary ammonium salt desulfurization ionic liquid or an imidazole desulfurization ionic liquid.

[0040] In this embodiment, the method is applicable to the detection of ionic liquid samples with an effective ingredient concentration in the range of 5%-30%.

[0041] Specifically, the purpose of heat treatment in S2 is to simulate the high-temperature conditions in the desulfurization process and eliminate interference from volatile impurities in the sample.

[0042] The method exhibits a repeatability error of ≤1.2% for the detection of thiosulfate ions in ionic liquids, with a spiked recovery rate between 98.5% and 102.3%. The entire determination process, from sample preparation to result calculation, takes no more than 1 hour.

[0043] Calculation formula: Calculate the mass concentration of thiosulfate in the sample based on titration data and chemical reaction equation.

[0044] Specifically, this embodiment presents a simplified method for determining the effective components of ionic liquids used in desulfurization. It utilizes the absorption characteristics of the effective components of the ionic liquid for SO2, creating a buffering effect on pH. 2 ml of the ionic liquid is dissolved in 40 ml of deionized water, heated at 105°C for 30 min, and deionized water is added to the original volume. The solution is then titrated with 0.5 mol / L hydrochloric acid until the pH reaches 2.32, followed by titration with 0.5 mol / L sodium hydroxide solution until the pH reaches 10. The concentration of the effective components is then calculated. The specific experimental steps are as follows:

[0045] Sample preparation: Dissolve 2 ml of ionic liquid in 40 ml of deionized water to ensure that the sample contains the active ingredient to be tested.

[0046] Heat treatment: The mixed solution is heated at 105°C for 30 minutes to simulate the high-temperature conditions in the desulfurization process.

[0047] Volume replenishment: After heating, add deionized water to the original volume to maintain a constant solution concentration.

[0048] Acid-base titration: Titrate with 0.5 mol / L hydrochloric acid until pH equals 2.32, and record the volume of hydrochloric acid consumed; then titrate with 0.5 mol / L sodium hydroxide solution until pH=10, and record the volume of sodium hydroxide consumed.

[0049] The calculation formula is as follows: Based on the titration data and the chemical reaction equation, the mass concentration of thiosulfate in the sample is calculated. The calculation formula is as follows: C% = 0.09 * cNaOH * VNaOH / Vsample.

Claims

1. A simplified method for determining the effective components of ionic liquids used in desulfurization, characterized in that, Includes the following steps: S1 Sample preparation: Dissolve the ionic liquid sample in deionized water to obtain the mixed solution to be tested; S2 Heating treatment: The mixed solution to be tested is heated at a set temperature for a set duration; S3 Volume replenishment: After heating is complete, add deionized water to the volume of the mixed solution to be tested as stated before heating; S4 Acid-Base Titration: First, titrate with a hydrochloric acid solution of a set concentration until the pH of the mixed solution reaches the first set value, and record the volume of hydrochloric acid solution consumed; then titrate with a sodium hydroxide solution of a set concentration until the pH of the mixed solution reaches the second set value, and record the volume of sodium hydroxide solution consumed. S5 Result Calculation: Based on the recorded volume of sodium hydroxide solution consumed, the concentration of sodium hydroxide solution, and the volume of the ionic liquid sample, the mass concentration of the effective component in the ionic liquid is calculated using the calculation formula.

2. The simplified method for determining the effective components of ionic liquids used for desulfurization according to claim 1, characterized in that, In S1, 2 ml of the ionic liquid sample was dissolved in 40 ml of deionized water.

3. The simplified method for determining the effective components of ionic liquids used for desulfurization according to claim 1, characterized in that, In S2, the set temperature is 105°C and the set duration is 30 minutes.

4. The simplified method for determining the effective components of ionic liquids used for desulfurization according to claim 1, characterized in that, In S4, the concentration of the hydrochloric acid solution is 0.5 mol / L, and the first set pH value is 2.32; the concentration of the sodium hydroxide solution is 0.5 mol / L, and the second set pH value is 10.

5. The simplified method for determining the effective components of ionic liquids used for desulfurization according to claim 1, characterized in that, In S5, the calculation formula is: C% = 0.09 × cNaOH × VNaOH / Vsample, where C% is the mass concentration of the effective component of the ionic liquid, cNaOH is the concentration of the sodium hydroxide solution, VNaOH is the volume of sodium hydroxide solution consumed, and Vsample is the volume of the ionic liquid sample.

6. The simplified method for determining the effective components of ionic liquids used for desulfurization according to claim 1, characterized in that, The ionic liquid is a quaternary ammonium salt desulfurization ionic liquid or an imidazole desulfurization ionic liquid.