Coloring agent for safety warning of gas leakage
By preparing the ZIF-8 composite powder of titanium dioxide microspheres loaded with bromothymol blue and sodium fluorescein, the problem of easy olfactory leakage and stability of gas leakage odorants is solved, and reliable visual warning and olfactory supplementation in extreme environments is achieved, which improves gas safety.
Patent Information
- Application Number
- CN202510536392.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-27
- Publication Date
- 2025-07-08
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
Existing gas leak odorants rely on olfactory perception to easily cause leakage judgments. Traditional visual colorants have poor stability and fail at extreme temperatures, making it impossible to build a reliable dual early warning system.
Titanium dioxide microspheres were prepared as bromothymol blue carrier by hydrothermal synthesis. Combined with ZIF-8 and sodium fluorescein, the composite powder was formed by ball milling and dispersing agent to achieve complementary olfactory and visual signals, and even dispersed in polyvinyl alcohol.
It significantly extends the color rendering life of the adder, improves safety performance and stability, can effectively warn in extreme environments, and improves the early warning reliability and dispersion stability of gas leakage.
Smart Images
Figure SMS_1
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of gas safety, and particularly relates to a colorant for gas leakage safety warning. Background Art
[0002] As a rich natural resource stored in nature, natural gas has become an important pillar of the modern social energy system with the characteristics of high efficiency, convenience, cleanness and environmental protection, marking a major progress of mankind in the field of energy utilization. With its in-depth popularization in the fields of industry, people's livelihood, etc., the safe use of natural gas has become a key issue of global concern. However, gas leakage accidents still occur frequently, and the current mainstream odorant technologies have significant limitations: relying on a single mode of olfactory perception, it is prone to misjudgment in the case of olfactory fatigue and complex odor environments; traditional visual colorants mostly use organic dyes, which have safety hazards such as low ignition point and easy chemical reaction with gas; existing products are prone to color change failure below -20°C or above 60°C, and have poor stability; therefore, developing a new type of colorant with safety, stability and visual warning functions, and constructing a "olfactory + visual" dual warning system has become an urgent need to break through the existing technical bottlenecks and ensure gas safety. Summary of the Invention
[0003] To solve the above problems, the present invention proposes a colorant for gas leakage safety warning.
[0004] The present invention provides a colorant for gas leakage safety warning, comprising the following raw materials in parts by mass: 60 - 80 parts of composite powder, 60 - 70 parts of solvent, 10 - 15 parts of polyvinyl alcohol, and 3 - 5 parts of stabilizer.
[0005] Preferably, the composite powder is prepared by the following method: Mix the loaded product, MOF powder and odor additive, perform the first ball milling, add nano-silica and dispersant, and perform the second ball milling to obtain the composite powder.
[0006] Preferably, the loaded product is prepared by the following method: A1. Add titanium oxysulfate to deionized water, stir, adjust the pH, transfer to a high-pressure reaction kettle, heat and react for 10 - 15 h, centrifuge, wash, and dry to obtain titanium dioxide microspheres; A2. Add titanate coupling agent to deionized water, stir; add titanium dioxide microspheres, heat and stir, centrifuge, wash, and dry to obtain modified titanium dioxide microspheres; A3. Add bromothymol blue to deionized water, adjust the pH, stir, add modified titanium dioxide microspheres, stir, centrifuge, and dry to obtain the loaded product.
[0007] Preferably, the components in the step A1 include the following parts by mass: 15-20 parts of titanium oxysulfate and 80-100 parts of deionized water; the components in the step A2 include the following parts by mass: 1-2 parts of titanate coupling agent, 10-15 parts of titanium dioxide microspheres, and 60-80 parts of deionized water; the components in the step A3 include the following parts by mass: 0.5-1 part of bromothymol blue, 8-15 parts of modified titanium dioxide microspheres, and 60-80 parts of deionized water.
[0008] Preferably, the odor additive includes at least one of tetrahydrothiophene, butanethiol, and dimethyl sulfide.
[0009] Preferably, the dispersant includes at least one of polyvinylpyrrolidone, sodium dodecyl sulfate, and chitosan.
[0010] Preferably, the titanate coupling agent includes at least one of isopropyl tris(dioctylpyrophosphato)titanate and isopropyl di(dioctylphosphite)titanate.
[0011] Preferably, the MOF powder is prepared by the following method: B1. Disperse zinc nitrate and cobalt acetate in deionized water, add 2-methylimidazole, stir, place in a microwave reactor, react for 35-50 min, centrifuge, wash, and dry to obtain ZIF-8; B2. Mix ZIF-8 with sodium fluorescein, ultrasonically disperse in methanol, heat and stir for 10-12 h, centrifuge, and dry to obtain MOF powder.
[0012] Preferably, the components in the step B1 include the following parts by mass: 5-8 parts of zinc nitrate, 0.5-2 parts of cobalt acetate, 6-10 parts of 2-methylimidazole, and 100-150 parts of deionized water; the components in the step B2 include the following parts by mass: 10-15 parts of ZIF-8, 1-4 parts of sodium fluorescein, and 80-100 parts of methanol.
[0013] Preferably, the composite powder includes the following parts by mass: 20-30 parts of the loaded product, 25-35 parts of MOF powder, 15-20 parts of odor additive, 8-15 parts of nano-silica, and 1-3 parts of dispersant.
[0014] Preferably, the first ball milling includes: at room temperature, ball milling at a rate of 300-400 rpm for 2-3 h, controlling the ball-to-material ratio to be 15:1, selecting zirconia balls with a ball diameter of 3 mm.
[0015] Preferably, the second ball milling includes: at room temperature, ball milling at a rate of 180-260 rpm for 5-7 h, controlling the ball-to-material ratio to be 15:1, selecting zirconia balls with a ball diameter of 3 mm.
[0016] The present invention also provides a preparation method of a colorant for gas leakage safety warning, comprising the following steps: Add a solvent into a reaction kettle, heat it, add polyvinyl alcohol while stirring, stir evenly, add a composite powder, perform ultrasonic dispersion, then add a stabilizer, stir evenly, and seal and age for 12 - 24 h to obtain the colorant for gas leakage safety warning.
[0017] Preferably, the solvent includes at least one of dipropylene glycol butyl ether, dipropylene glycol methyl ether, and butyl acetate.
[0018] Preferably, the stabilizer includes at least one of citric acid, tea polyphenols, and tartaric acid.
[0019] The present invention has the following beneficial effects: The present invention prepares titanium dioxide microspheres with a porous structure through a hydrothermal synthesis process and uses them as carriers for bromothymol blue. The three-dimensional pore system of the titanium dioxide microspheres can achieve stable immobilization of bromothymol blue through physical adsorption and intermolecular forces. Its loading amount can be precisely controlled by regulating the duration of the hydrothermal reaction, thereby constructing an indicator slow-release system and significantly extending the color development life. The prepared nanoscale titanium dioxide microspheres have inert chemical properties, no chemical reaction activity with gas components such as natural gas and liquefied petroleum gas, and a far higher ignition point than organic dyes, which improves the safety performance of the colorant from the material essence. The present invention uses zinc nitrate, cobalt acetate, and 2-methylimidazole as raw materials to synthesize ZIF-8 metal-organic framework through a coordination self-assembly reaction. ZIF-8 and sodium fluorescein are ultrasonically assisted for loading, and the spatial confinement effect of its regular pores and coordination bond action are used to achieve the encapsulation and stabilization of sodium fluorescein molecules. This loading system effectively isolates the photodegradation, solvent extraction, and chemical decomposition of sodium fluorescein by the external environment, which is significantly better than the traditional process of directly adding organic dyes, and further improves the problem of color development failure in extreme environments.
[0020] The present invention mixes a loaded product, MOF powder, and tetrahydrothiophene, and after ball milling, nano-silica and a dispersant are introduced; the loaded product can undergo a color change due to contact with air humidity, acidic gas, or temperature change through a surface-modified pH / environment-responsive dye during gas leakage, thereby achieving environmentally sensitive visual warning; the MOF powder utilizes the high adsorption capacity and stability of the MOF porous structure to uniformly disperse and slowly release sodium fluorescein, emitting fluorescence at a specific wavelength under ultraviolet or natural light to enhance visual recognition; then, an odor additive is introduced to achieve signal complementarity between smell and vision, solve the problem of false negative caused by fatigue or high-concentration odor environment in single olfactory warning, and improve the reliability of safety warning. The introduction of nano-silica can prevent particle agglomeration and ensure that the composite powder can be uniformly dispersed in polyvinyl alcohol; the introduction of the dispersant coats the particle surface, reduces the interfacial tension, improves the dispersibility of the powder in polyvinyl alcohol, and thus extends the service life of the colorant. Nano-silica inhibits particle agglomeration through a physical barrier effect, and in cooperation with the steric hindrance effect of the dispersant, significantly improves the dispersion uniformity of the composite powder in the polyvinyl alcohol base material, effectively avoiding sedimentation inactivation and extending the functional life of the colorant during storage and use. This composite system realizes multi-modal output of warning signals, enhanced environmental adaptability, and improved dispersion stability through the synergistic effect of multiple components, providing a systematic solution for the accurate detection of gas leakage. Detailed implementation mode
[0021] Sodium fluorescein was purchased from Shandong Qiyuan Chemical Co., Ltd., with an active ingredient content of 99%; tetrahydrothiophene was purchased from Shandong Qiangsen Chemical Co., Ltd.; nano-silica was purchased from Zhejiang Manli Nano Technology Co., Ltd., model: ML-SiO2-N21, particle size 20 nm; bromothymol blue was purchased from Shandong Duoju Chemical Co., Ltd., chemically pure; polyvinyl alcohol was purchased from Zhengzhou Shuoyuan Biotechnology Co., Ltd., model: 26-99L.
[0022] Example 1 A colorant for gas leakage safety warning comprises the following raw materials in parts by mass: 60 parts of composite powder, 60 parts of solvent, 10 parts of polyvinyl alcohol, and 3 parts of stabilizer.
[0023] Among them, the composite powder is prepared by the following method: Mix the loaded product, MOF powder and odor additive, and conduct the first ball milling at room temperature at a rate of 300 rpm for 2 h, control the ball-to-material ratio to be 15:1, select zirconia balls with a ball diameter of 3 mm, add nano-silica and a dispersant, then conduct the second ball milling at room temperature at a rate of 180 rpm for 5 h, control the ball-to-material ratio to be 15:1, select zirconia balls with a ball diameter of 3 mm to obtain a composite powder; among them, there are 20 parts of the loaded product, 25 parts of MOF powder, 15 parts of odor additive, 8 parts of nano-silica, and 1 part of dispersant; among them, the odor additive is tetrahydrothiophene and the dispersant is polyvinylpyrrolidone.
[0024] Among them, the loaded product is prepared by the following method: A1. Add titanium oxysulfate to deionized water, stir at 100 rpm for 15 min, adjust the pH to 1, transfer it to a high-pressure reactor, heat to 150 °C, conduct a hydrothermal reaction for 10 h, centrifuge at 3000 rpm for 3 min, wash 3 times with deionized water, and dry at 60 °C for 4 h to obtain titanium dioxide microspheres; among them, there are 15 parts of titanium oxysulfate and 80 parts of deionized water; A2. Add a titanate coupling agent to deionized water, stir at 80 rpm for 5 min; add titanium dioxide microspheres, heat to 60 °C, stir at 100 rpm for 2 h, centrifuge at 3000 rpm for 3 min, wash 3 times with deionized water, and dry at 60 °C for 4 h to obtain modified titanium dioxide microspheres; among them, there is 1 part of titanate coupling agent, 10 parts of titanium dioxide microspheres, and 60 parts of deionized water, and the titanate coupling agent is isopropyl tri(dioctylpyrophosphate acyl) titanate; A3. Add bromothymol blue to deionized water, adjust the pH to 4, stir at 60 rpm for 5 min, add modified titanium dioxide microspheres, stir at 60 rpm for 5 h, centrifuge at 3000 rpm for 3 min, and dry at 60 °C for 4 h to obtain the loaded product; among them, there are 0.5 parts of bromothymol blue, 8 parts of modified titanium dioxide microspheres, and 60 parts of deionized water.
[0025] Among them, the MOF powder is prepared by the following method: B1. Disperse zinc nitrate and cobalt acetate in deionized water, add 2-methylimidazole, stir at 100 rpm for 20 min, then place it in a microwave reactor, control the power to be 400 W, react for 35 min, centrifuge at 4000 rpm for 5 min, wash 3 times with deionized water, and dry at 50 °C for 5 h to obtain ZIF-8; among them, there are 5 parts of zinc nitrate, 0.5 parts of cobalt acetate, 6 parts of 2-methylimidazole, and 100 parts of deionized water; B2. Mix ZIF-8 with sodium fluorescein, ultrasonically disperse it in methanol, ultrasonically disperse it at 20 kHz for 10 min, then heat it to 60 °C, stir it at 100 rpm for 10 h, centrifuge it at 4000 rpm for 5 min, and dry it at 50 °C for 5 h to obtain MOF powder; among them, 10 parts of ZIF-8, 1 part of sodium fluorescein, and 80 parts of methanol.
[0026] A preparation method of a colorant for gas leakage safety warning, comprising the following steps: Add the solvent to the reaction kettle, heat it to 40 °C, control the stirring rate to 100 rpm, add polyvinyl alcohol while stirring, stir for 10 min, add the composite powder, ultrasonically disperse it at 20 kHz for 20 min, then add the stabilizer, stir at 100 rpm for 20 min, and seal and age it at room temperature for 12 h to obtain the colorant for gas leakage safety warning; among them, the solvent is dipropylene glycol monobutyl ether, and the stabilizer is citric acid.
[0027] Example 2 A colorant for gas leakage safety warning, comprising the following raw materials in parts by mass: 80 parts of composite powder, 70 parts of solvent, 15 parts of polyvinyl alcohol, and 5 parts of stabilizer.
[0028] Among them, the composite powder is prepared by the following method: Mix the loaded product, MOF powder and odor additive, ball mill for the first time, at room temperature, ball mill at a rate of 400 rpm for 3 h, control the ball-to-material ratio to 15:1, select zirconia balls with a ball diameter of 3 mm, add nano-silica and dispersant, ball mill for the second time, at room temperature, ball mill at a rate of 260 rpm for 7 h, control the ball-to-material ratio to 15:1, select zirconia balls with a ball diameter of 3 mm, to obtain the composite powder; among them, 30 parts of the loaded product, 35 parts of MOF powder, 20 parts of odor additive, 15 parts of nano-silica, and 3 parts of dispersant; among them, the odor additive is butanethiol, and the dispersant is sodium dodecyl sulfate.
[0029] Among them, the loaded product is prepared by the following method: A1. Add titanium oxysulfate to deionized water, stir at 150 rpm for 120 min, adjust the pH to 3, transfer it to a high-pressure reaction kettle, heat it to 180 °C, carry out hydrothermal reaction for 15 h, centrifuge at 4000 rpm for 5 min, wash it with deionized water 3 times, and dry it at 70 °C for 6 h to obtain titanium dioxide microspheres; among them, 20 parts of titanium oxysulfate and 100 parts of deionized water; A2. Add the titanate coupling agent to deionized water, stir at 100 rpm for 10 min; add titanium dioxide microspheres, heat to 80 °C, stir at 150 rpm for 3 h, centrifuge at 4000 rpm for 5 min, wash 3 times with deionized water, and dry at 70 °C for 6 h to obtain modified titanium dioxide microspheres; among them, 2 parts of titanate coupling agent, 15 parts of titanium dioxide microspheres, and 80 parts of deionized water; the titanate coupling agent is tetra-isopropyl di(dioctylphosphite) titanate; A3. Add bromothymol blue to deionized water, adjust the pH to 6, stir at 80 rpm for 8 min, add modified titanium dioxide microspheres, stir at 80 rpm for 8 h, centrifuge at 4000 rpm for 5 min, and dry at 70 °C for 6 h to obtain the loaded product; among them, 1 part of bromothymol blue, 15 parts of modified titanium dioxide microspheres, and 80 parts of deionized water.
[0030] Among them, the MOF powder is prepared by the following method: B1. Disperse zinc nitrate and cobalt acetate in deionized water, add 2-methylimidazole, stir at 150 rpm for 30 min, then place it in a microwave reactor, control the power at 450 W, react for 50 min, centrifuge at 5000 rpm for 8 min, wash 3 times with deionized water, and dry at 60 °C for 7 h to obtain ZIF-8; among them, 8 parts of zinc nitrate, 2 parts of cobalt acetate, 10 parts of 2-methylimidazole, and 150 parts of deionized water; B2. Mix ZIF-8 with sodium fluorescein, ultrasonically disperse in methanol, ultrasonically disperse at 30 kHz for 15 min, then heat to 70 °C, stir at 150 rpm for 12 h, centrifuge at 5000 rpm for 8 min, and dry at 60 °C for 7 h to obtain MOF powder; among them, 15 parts of ZIF-8, 4 parts of sodium fluorescein, and 100 parts of methanol.
[0031] A preparation method of a colorant for gas leakage safety warning includes the following steps: Add the solvent to the reaction kettle, heat to 50 °C, control the stirring rate at 200 rpm, add polyvinyl alcohol while stirring, stir for 20 min, add the composite powder, ultrasonically disperse at 30 kHz for 30 min, then add the stabilizer, stir at 150 rpm for 30 min, and seal and age at room temperature for 24 h to obtain the colorant for gas leakage safety warning; among them, the solvent is dipropylene glycol methyl ether; the stabilizer is tea polyphenols.
[0032] Example 3 A colorant for gas leakage safety warning, comprising the following raw materials in parts by mass: 70 parts of composite powder, 65 parts of solvent, 13 parts of polyvinyl alcohol, and 4 parts of stabilizer.
[0033] Among them, the composite powder is prepared by the following method: Mix the loaded product, MOF powder and odor additive, and perform the first ball milling. At room temperature, ball mill at a rate of 350 rpm for 2.5 h, control the ball-to-material ratio to be 15:1, select zirconia balls with a ball diameter of 3 mm, add nano-silica and dispersant, and perform the second ball milling. At room temperature, ball mill at a rate of 220 rpm for 6 h, control the ball-to-material ratio to be 15:1, select zirconia balls with a ball diameter of 3 mm, to obtain the composite powder; among them, 25 parts of the loaded product, 30 parts of MOF powder, 18 parts of odor additive, 13 parts of nano-silica, and 2 parts of dispersant; among them, the odor additive is dimethyl sulfide; the dispersant is chitosan.
[0034] Among them, the loaded product is prepared by the following method: A1. Add titanium oxysulfate to deionized water, stir at 130 rpm for 18 min, adjust the pH to 2, transfer it to a high-pressure reaction kettle, heat to 170 °C, perform hydrothermal reaction for 13 h, centrifuge at 3500 rpm for 4 min, wash with deionized water 3 times, and dry at 65 °C for 5 h to obtain titanium dioxide microspheres; among them, 18 parts of titanium oxysulfate and 90 parts of deionized water; A2. Add titanate coupling agent to deionized water, stir at 90 rpm for 7 min; add titanium dioxide microspheres, heat to 70 °C, stir at 130 rpm for 2.5 h, centrifuge at 3500 rpm for 4 min, wash with deionized water 3 times, and dry at 65 °C for 5 h to obtain modified titanium dioxide microspheres; among them, 1.5 parts of titanate coupling agent, 13 parts of titanium dioxide microspheres, and 70 parts of deionized water; the titanate coupling agent is isopropyl tri(dioctylpyrophosphate acyl) titanate; A3. Add bromothymol blue to deionized water, adjust the pH to 5, stir at 70 rpm for 7 min, add modified titanium dioxide microspheres, stir at 70 rpm for 6 h, centrifuge at 3500 rpm for 4 min, and dry at 65 °C for 5 h to obtain the loaded product; among them, 0.8 part of bromothymol blue, 12 parts of modified titanium dioxide microspheres, and 70 parts of deionized water.
[0035] Among them, the MOF powder is prepared by the following method: B1. Disperse zinc nitrate and cobalt acetate in deionized water, add 2-methylimidazole, stir at 130 rpm for 25 min, then place it in a microwave reactor, control the power to be 430 W, react for 45 min, centrifuge at 4500 rpm for 7 min, wash with deionized water 3 times, and dry at 55 °C for 6 h to obtain ZIF-8; among them, 7 parts of zinc nitrate, 1 part of cobalt acetate, 8 parts of 2-methylimidazole, and 130 parts of deionized water; B2. Mix ZIF-8 with sodium fluorescein, ultrasonically disperse in methanol, ultrasonically disperse at 25 kHz for 12 min, then heat to 65 °C, stir at 130 rpm for 11 h, centrifuge at 4500 rpm for 7 min, and dry at 55 °C for 6 h to obtain MOF powder; among them, 12 parts of ZIF-8, 3 parts of sodium fluorescein, and 90 parts of methanol.
[0036] A preparation method of a colorant for gas leakage safety warning, comprising the following steps: Add the solvent to the reaction kettle, heat to 45 °C, control the stirring rate at 150 rpm, add polyvinyl alcohol while stirring, stir for 15 min, add the composite powder, ultrasonically disperse at 25 kHz for 25 min, then add the stabilizer, stir at 130 rpm for 25 min, and seal and age at room temperature for 18 h to obtain the colorant for gas leakage safety warning; among them, the solvent is butyl acetate and the stabilizer is tartaric acid.
[0037] Comparative Example 1 Comparative Example 1 is the same as Example 1, the only difference is that the preparation method of the composite powder is different, specifically as follows: The composite powder is prepared by the following method: Mix the supported product, MOF powder, odor additive, nano-silica and dispersant, ball mill at a rate of 300 rpm at room temperature for 5 h, control the ball-to-material ratio at 15:1, select zirconia balls with a ball diameter of 3 mm to obtain the composite powder; among them, 20 parts of the supported product, 25 parts of MOF powder, 15 parts of odor additive, 8 parts of nano-silica, and 1 part of dispersant; among them, the odor additive is tetrahydrothiophene and the dispersant is polyvinylpyrrolidone.
[0038] Comparative Example 2 Comparative Example 2 is the same as Example 1, the only difference is that the preparation method of the composite powder is different, specifically as follows: The composite powder is prepared by the following method: Mix bromothymol blue, MOF powder and odor additive, ball mill for the first time, ball mill at a rate of 300 rpm at room temperature for 2 h, control the ball-to-material ratio at 15:1, select zirconia balls with a ball diameter of 3 mm, add nano-silica and polyvinylpyrrolidone, ball mill for the second time, ball mill at a rate of 180 rpm at room temperature for 5 h, control the ball-to-material ratio at 15:1, select zirconia balls with a ball diameter of 3 mm to obtain the composite powder; among them, 20 parts of bromothymol blue, 25 parts of MOF powder, 15 parts of odor additive, 8 parts of nano-silica, and 1 part of dispersant; among them, the odor additive is tetrahydrothiophene and the dispersant is polyvinylpyrrolidone.
[0039] Comparative Example 3 Comparative Example 3 is the same as Example 1, except that the preparation method of the composite powder is different, which is specifically as follows: The composite powder was prepared by the following method: Mix the loaded product, sodium fluorescein and the odor additive, and perform the first ball milling. At room temperature, ball mill at a rate of 300 rpm for 2 h, control the ball-to-material ratio to be 15:1, select zirconia balls with a ball diameter of 3 mm, add nano-silica and a dispersant, and perform the second ball milling. At room temperature, ball mill at a rate of 180 rpm for 5 h, control the ball-to-material ratio to be 15:1, select zirconia balls with a ball diameter of 3 mm, to obtain the composite powder; wherein, there are 20 parts of the loaded product, 25 parts of the MOF powder, 15 parts of the odor additive, 8 parts of nano-silica, and 1 part of the dispersant; wherein, the odor additive is tetrahydrothiophene and the dispersant is polyvinylpyrrolidone.
[0040] Comparative Example 4 Comparative Example 4 is the same as Example 1, except that the preparation method of the composite powder is different, which is specifically as follows: Among them, the composite powder was prepared by the following method: Mix the loaded product, MOF powder and the odor additive, and perform the first ball milling. At room temperature, ball mill at a rate of 300 rpm for 2 h, control the ball-to-material ratio to be 15:1, select zirconia balls with a ball diameter of 3 mm, add a dispersant, and perform the second ball milling. At room temperature, ball mill at a rate of 180 rpm for 5 h, control the ball-to-material ratio to be 15:1, select zirconia balls with a ball diameter of 3 mm, to obtain the composite powder; wherein, there are 20 parts of the loaded product, 25 parts of the MOF powder, 15 parts of the odor additive, and 1 part of the dispersant; wherein, the odor additive is tetrahydrothiophene and the dispersant is polyvinylpyrrolidone.
[0041] Comparative Example 5 Comparative Example 5 is the same as Example 1, except that the preparation method of the composite powder is different, which is specifically as follows: Among them, the composite powder was prepared by the following method: Mix the loaded product, MOF powder and the odor additive, and perform the first ball milling. At room temperature, ball mill at a rate of 300 rpm for 2 h, control the ball-to-material ratio to be 15:1, select zirconia balls with a ball diameter of 3 mm, add nano-silica, and perform the second ball milling. At room temperature, ball mill at a rate of 180 rpm for 5 h, control the ball-to-material ratio to be 15:1, select zirconia balls with a ball diameter of 3 mm, to obtain the composite powder; wherein, there are 20 parts of the loaded product, 25 parts of the MOF powder, 15 parts of the odor additive, and 8 parts of nano-silica; wherein, the odor additive is tetrahydrothiophene.
[0042] Performance Test Control the ratio of the amount of the colorant added to the amount of natural gas to be 18 mg: 1 m 3; The gas pressure difference is regulated by a pressure regulating valve, and the colorant is injected into the main gas pipeline through a microporous colorant injection tube. At the same time, the mixing uniformity is enhanced by a baffle or a flow disturbance structure. The following performance tests are carried out on the colorants for gas leakage safety warning prepared in Examples 1-3 and Comparative Examples 1-5: Color response characteristics: The color change ΔE value before and after leakage is measured by a color difference meter, and the leakage environment is simulated (the relative humidity is controlled at 80% and the H2S concentration is 5 ppm) to trigger the color change characteristics of the colorant; Odor irritation intensity test: Twenty judges are selected to evaluate the odor irritation intensity by olfaction, and the grades are divided into 6 levels: level 1 (no peculiar smell) to level 6 (intolerable); Stability test: The colorant is placed in a high and low temperature alternating test chamber, kept at -30°C for 24 h, then heated to 80°C and kept for 24 h. This is regarded as a complete temperature cycle. The above cycle operation is repeated for a total of ten cycles. After each cycle, the color change ΔE value of the colorant is detected by a color difference meter (according to the ISO11664-4 standard) to evaluate its color stability in an extreme temperature fluctuation environment; The test results are as follows: Table 1 Performance test results
[0043] The performance data of Example 1 and Comparative Example 1 show that ball milling the loaded product, MOF powder and tetrahydrothiophene can break the interparticle agglomeration and achieve initial uniform dispersion. Moreover, tetrahydrothiophene is adsorbed on the surfaces of the loaded product and MOF powder during mechanical collision, laying a foundation for secondary dispersion; the second low-speed and long-time ball milling forms a core-shell composite structure with the loaded product, MOF powder, and tetrahydrothiophene as the core, a polyvinylpyrrolidone layer coated on the surface and nano-silica embedded, thereby improving the subsequent compatibility with the resin matrix, fully improving the dispersibility and stability, and being able to achieve a long-term slow-release effect.
[0044] According to the test results of Example 1 and Comparative Examples 2-3, the bromothymol blue-loaded nano-titanium dioxide microspheres and the fluorescein sodium-loaded MOF powder can construct a more stable functional carrier structure for the colorant by virtue of their unique inorganic framework structure and porous coordination network. Compared with the unloaded control sample, this composite system can effectively inhibit the component failure or structure collapse caused by environmental factors during long-term use, thereby significantly improving the service life and warning performance stability of the colorant.
[0045] According to the test results of Example 1 and Comparative Examples 4-5, it can be seen that the synergistic introduction of nano-silica and dispersant plays a key role in optimizing the dispersion performance of colorant. Through the steric hindrance effect of nano-sized particles and the interfacial modification effect of polymer dispersants, the particle agglomeration phenomenon in the composite system is significantly improved, which can effectively delay the functional decay of colorant during storage and use, and has important technical significance for extending its actual application life.
[0046] This specific embodiment is only an interpretation of the present invention, and it is not a limitation of the present invention. After reading this specification, those skilled in the art can make modifications to this embodiment without creative contributions as needed, but as long as they are within the scope of the claims of the present invention, they are protected by the patent law.
Claims
1. A colorant for gas leakage safety warning, characterized in that, It includes raw materials in the following parts by mass: 60 - 80 parts of composite powder, 60 - 70 parts of solvent, 10 - 15 parts of polyvinyl alcohol, 3 - 5 parts of stabilizer.
2. The colorant for gas leakage safety warning according to claim 1, characterized in that, The composite powder is prepared by the following method: Mix the loaded product, MOF powder and odor additive, conduct the first ball milling, add nano - silica and dispersant, and conduct the second ball milling to obtain the composite powder.
3. A colorant for gas leakage safety warning according to claim 2, characterized in that, The loaded product is prepared by the following method: A1. Add titanium oxysulfate to deionized water, stir, adjust the pH, transfer it to a high - pressure reactor, heat and react for 10 - 15 h, centrifuge, wash, and dry to obtain titanium dioxide microspheres; A2. Add titanate coupling agent to deionized water and stir; Add the titanium dioxide microspheres, heat and stir, centrifuge, wash, and dry to obtain modified titanium dioxide microspheres; A3. Add bromothymol blue to deionized water, adjust the pH, stir, add the modified titanium dioxide microspheres, stir, centrifuge, and dry to obtain the loaded product.
4. A colorant for gas leakage safety warning according to claim 3, characterized in that, In step A1, it includes the following components in parts by mass: 15 - 20 parts of titanium oxysulfate, 80 - 100 parts of deionized water; in step A2, it includes the following components in parts by mass: 1 - 2 parts of titanate coupling agent, 10 - 15 parts of titanium dioxide microspheres, 60 - 80 parts of deionized water; in step A3, it includes the following components in parts by mass: 0.5 - 1 part of bromothymol blue, 8 - 15 parts of modified titanium dioxide microspheres, 60 - 80 parts of deionized water.
5. A colorant for gas leakage safety warning according to claim 2, characterized in that, The MOF powder is prepared by the following method: B1. Disperse zinc nitrate and cobalt acetate in deionized water, add 2 - methylimidazole, stir, place it in a microwave reactor, react for 35 - 50 min, centrifuge, wash, and dry to obtain ZIF - 8; B2. Mix ZIF - 8 and sodium fluorescein, ultrasonically disperse it in methanol, heat and stir for 10 - 12 h, centrifuge, and dry to obtain the MOF powder.
6. The colorant for gas leakage safety warning according to claim 5, characterized in that, In step B1, it includes the following components in parts by mass: 5 - 8 parts of zinc nitrate, 0.5 - 2 parts of cobalt acetate, 6 - 10 parts of 2 - methylimidazole, 100 - 150 parts of deionized water; in step B2, it includes the following components in parts by mass: 10 - 15 parts of ZIF - 8, 1 - 4 parts of sodium fluorescein, 80 - 100 parts of methanol.
7. The colorant for gas leakage safety warning according to claim 2, characterized in that, The composite powder includes the following components in parts by mass: 20 - 30 parts of loaded product, 25 - 35 parts of MOF powder, 15 - 20 parts of odor additive, 8 - 15 parts of nano - silica, 1 - 3 parts of dispersant.
8. The colorant for gas leakage safety warning according to claim 2, characterized in that, The first ball milling includes: at room temperature, ball - mill at a rate of 300 - 400 rpm for 2 - 3 h, control the ball - to - material ratio to be 15:1, select zirconia balls with a ball diameter of 3 mm; the second ball milling includes: at room temperature, ball - mill at a rate of 180 - 260 rpm for 5 - 7 h, control the ball - to - material ratio to be 15:1, select zirconia balls with a ball diameter of 3 mm.
9. A preparation method of a colorant for gas leakage safety warning according to any one of claims 1-8, characterized in that, It includes the following steps: Add the solvent to the reaction kettle, heat, add polyvinyl alcohol while stirring, stir evenly, add the composite powder, ultrasonically disperse it, then add the stabilizer, stir evenly, and seal and age for 12 - 24 h to obtain the colorant for gas leakage safety warning.
10. The preparation method of a colorant for gas leakage safety warning according to claim 9, characterized in that, The solvent includes at least one of dipropylene glycol butyl ether, dipropylene glycol methyl ether, and butyl acetate; the stabilizer includes at least one of citric acid, tea polyphenols, and tartaric acid.