Method for preparing an oil leak detection sensor based on metal oxide nanoplatelets

Abstract

The application discloses a kind of oil leakage detection sensor preparation methods based on metal oxide nanosheet, comprising: step (1), the oxalate and potassium chloride powder with mass ratio of 10-30:1 are weighed, and grinding is carried out;Step (2), the mixed powder after grinding uniformly is ball milled, until oxalate powder is crushed and cut into flaky;Step (3), after the mixed powder after ball milling is dried, calcination is carried out, the metal ion decomposed from oxalate is oxidized into metal oxide powder, and potassium ion is modified on the surface of metal oxide;Step (4), after further grinding metal oxide powder, form liquid with deionized water, wherein the mass ratio of metal oxide powder and deionized water is 2-6:1;Step (5), liquid is added on interdigital electrode, and oil leakage detection sensor is obtained.The application can be used in nuclear power plant, oil and gas pipeline, oil tank and other places, and oil substances can be effectively detected whether leakage.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of oil leakage detection, and particularly relates to a preparation method of an oil leakage detection sensor based on metal oxide nanosheets. BACKGROUND

[0002] Fuel oil and crude oil are essential energy materials in the current industrial field, and hydraulic oil and lubricating oil are necessary for the normal operation of nuclear power equipment, aviation generators and other equipment. However, once oil substances leak, it will cause serious safety accidents and incalculable economic damage. In 2004, an oil and gas pipeline in Mexico leaked, causing an explosion that killed five people and caused more than 400 residents to relocate; in 2008, a hydraulic oil leak occurred in a Boeing 737, causing the plane to make an emergency landing and causing more than 100 passengers to be seriously frightened; in 2010, an oil spill occurred in Mexico, causing nearly five million barrels of crude oil to leak into the ocean, resulting in direct economic damage of hundreds of millions of dollars, which is the most serious oil spill event to date; in 2013, an oil leak occurred in a pipeline of a certain petrochemical company, causing a serious explosion, which resulted in 198 deaths and injuries; in 2018, a hydraulic oil leak occurred in a valve of a steam turbine in a power plant, causing a fire in the steam turbine system and causing a serious safety accident; in 2022, nearly 15,000 barrels of crude oil leaked along the coast of Peru, causing serious environmental pollution and preventing hundreds of fishermen from working.

[0003] Oil leakage has caused numerous safety accidents and significant economic damage, so it is necessary to take measures to effectively deal with the leakage of oil substances. Sensors are widely used in the identification and detection of various substances due to their miniaturization, high response and high sensitivity. In the monitoring method of oil substances, there are mainly optical sensors, acoustic sensors and electrochemical sensors. Invention patent CN103649710A discloses a fiber sensor structure for sensing liquid in a sealed oil storage tank. This sensor has the characteristic of being intrinsically safe against explosion, but the high manufacturing and use cost and inconvenient maintenance are the main factors limiting its application. Utility model patent CN202002781U discloses an acousto-optic sensor for oil leakage, which has an optical alarm module and a power indicator module. Invention patent CN110294231A discloses a device for detecting oil leakage at the bottom of an oil storage tank and an electrochemical oil sensing sensor. The sensing device is equipped with an alarm system, which can effectively and quickly realize oil leakage monitoring and alarm. However, a sensing material with high response to oil substances is a problem that needs to be solved in current research, and there is little research in this regard. SUMMARY

[0004] An object of the present application is to solve at least the above problems and to provide at least the advantages described later.

[0005] In view of the problems of low stability and low detection sensitivity of the sensing materials currently available for oil leakage detection, the application provides a two-dimensional metal oxide nanosheet and a preparation method and application of a sensor thereof, so as to effectively solve the above problems.

[0006] The application develops a preparation method of an oil leakage detection sensor based on metal oxide nanosheets. The preparation method first dries oxalate precursors, then oxalate and potassium chloride powders, and then places the ball-milled powder in a vacuum drying box for drying. After that, the above-mentioned powder is calcined in a muffle furnace to obtain metal oxide nanosheet powder. Finally, the preparation of the sensor is completed through ultrasonic dispersion, dripping and drying. The developed potassium ion modified metal oxide nanosheet can quickly and effectively detect oil leakage with high sensitivity.

[0007] In order to achieve these objects and other advantages according to the application, a preparation method of an oil leakage detection sensor based on metal oxide nanosheets is provided, and a potassium ion modified metal oxide nanosheet is used as a key material of the sensor for oil leakage detection. The preparation method of the potassium ion modified metal oxide nanosheet and the oil leakage detection sensor comprises the following steps:

[0008] Step (1), taking oxalate (including oxalate hydrate) as a precursor, two portions of oxalate with a mass of 2g each are weighed on two beakers, and phosphorus pentoxide is weighed on a beaker as a drying agent and dehydrating agent. The three beakers are placed in a vacuum drying box for vacuum drying treatment to remove the crystal water contained in the oxalate;

[0009] Two portions of potassium chloride powder with a mass of 0.1g are weighed, and the dried oxalate and potassium chloride powder are poured into a mortar according to the mass ratio of oxalate to potassium chloride of 20:1 for grinding, while stirring to mix them evenly;

[0010] Step (2), the above two portions of powder are poured into a ball milling tank containing a plurality of agate balls of different sizes for ball milling treatment. In the ball milling process, the oxalate powder is crushed and cut into thin sheets by the high impact force and shear force of the agate balls. The potassium ions have the effect of dispersing the oxalate powder in the ball milling process, which is beneficial to the size and distribution of the oxalate nanosheet powder being more uniform.

[0011] Step (3), the ball-milled powder is poured into two crucibles respectively and dried in a vacuum drying box to remove the crystal water formed in the ball milling process. The two crucibles are placed in a muffle furnace for high-temperature calcination in an air environment. The calcination process can decompose the oxalate, and the decomposed metal ions are oxidized into metal oxides with stable structure. Secondly, the calcination temperature is controlled to prevent the potassium chloride from being decomposed, so that the potassium ions are modified on the surface of the metal oxide.

[0012] Step (4), the powder in the crucible is poured into a mortar for grinding, and after sufficient grinding, the powder is bottled and labeled to complete the preparation of the potassium ion modified metal oxide nanosheet;

[0013] The above powder 20 mg is weighed in a beaker, 5 ml of deionized water is measured by a measuring cylinder and poured into the beaker containing the powder, and then a glass cup is used for stirring and placed in an ultrasonic cleaning instrument for ultrasonic dispersion;

[0014] Step (5), the above solution is sucked by a pipette, and the liquid is dropped on the interdigital electrode, and after the dropping is completed, it is placed in a drying oven for drying to complete the fixation of the material, and an oil leakage detection sensor is obtained.

[0015] Preferably, in step (1), the mass of the weighed phosphorus pentoxide is 1g, the vacuum drying condition is 80℃ for 12 hours, and the used phosphorus pentoxide needs harmless treatment, which needs to react with hot water to produce orthophosphoric acid, and then the PH value is adjusted to neutral by alkali liquor.

[0016] Preferably, in step (2), the number of large-sized agate balls is 20, the diameter is 10mm, the number of small-sized agate balls is 50, the diameter is 6mm, and the volume of the ball mill jar is 100ml.

[0017] Preferably, in step (2), the rated speed of the ball mill is 530rpm, the rated power is 1.5kW, the ball milling time is 12 hours, and during the ball milling, the powder deposited at the bottom is stirred uniformly every 1 hour to make the powder uniformly ball milled.

[0018] Preferably, in step (3), the vacuum drying temperature is 60℃, and the drying time is 6 hours.

[0019] Preferably, in step (3), the temperature rising process of the muffle furnace is controlled by a program, first rising to 200℃ at a speed of 1℃ / min, then rising to 380℃ at a speed of 2℃ / min, and keeping at 380℃ for 2 hours, and after the calcination is completed, the furnace is cooled to 60℃ before taking out.

[0020] Preferably, in step (4), the rated power of the ultrasonic cleaning instrument is 54w, the ultrasonic time is 30 minutes, and an ice bag is added during ultrasonic to maintain the water temperature below 30℃.

[0021] Preferably, in step (5), the liquid suctioning amount of the pipette is 1ml, the drying temperature is 60℃, and the drying time is 2 hours.

[0022] The present application at least includes the following beneficial effects:

[0023] 1. This patent invention relates to a method for preparing an oil leak detection sensor based on metal oxide nanosheets. The potassium ion-modified metal oxide nanosheets have a large specific surface area and excellent stability, enabling highly sensitive oil leak detection at room temperature and effectively and reliably determining the oil leak situation.

[0024] 2. The potassium ion-modified metal oxide nanosheet material of this invention can be combined with other materials to prepare composite materials with better performance, and can also be directly applied to fields such as sensing and catalysis. Different types of sensors made from this metal oxide nanosheet material can be used in nuclear power plants, oil and gas pipelines, oil storage tanks and other places, and can effectively detect whether oil substances are leaking.

[0025] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Attached Figure Description

[0026] Figure 1 It is the prepared K + / FESEM surface morphology of CuO nanosheets;

[0027] Figure 2 It is the prepared K + / TEM surface morphology of CuO nanosheets;

[0028] Figure 3 It is the prepared K + / TEM surface morphology of CuO nanosheets;

[0029] Figure 4 It is the prepared K + XRD pattern of CuO nanosheets;

[0030] Figure 5 It is the prepared K + / CuO nanosheets BET test image;

[0031] Figure 6 It is the prepared K + / Image of a CuO nanosheet resistive sensor;

[0032] Figure 7 It is the prepared K + / Performance test diagram of CuO nanosheet resistive sensor. Detailed Implementation

[0033] The present invention will now be described in further detail with reference to the accompanying drawings, so that those skilled in the art can implement it based on the description.

[0034] It should be understood that the terms such as "have", "contain" and "include" used in the patent do not exclude the presence or addition of one or more other elements or combinations thereof.

[0035] The patent uses the strong physical impact force and shear force of the unique interval mechanical ball milling method to impact the oxalate and potassium chloride powder into potassium ion doped oxalate nanosheet powder, and then prepares small size potassium ion modified metal oxide nanosheet powder with two-dimensional planar structure through high temperature calcination and grinding, so that the oil leakage detection sensitive material with large specific surface area and high stability is successfully prepared.

[0036] The potassium ion modified metal oxide nanosheet material of the present application has the characteristics of large specific surface area, high stability and high response speed, which can timely feedback the oil leakage information to the technical personnel and timely handle the leakage problem.

[0037] The oxalate in the method of the present application includes but is not limited to copper oxalate, tin oxalate, cobalt oxalate, vanadyl oxalate, barium oxalate, niobium oxalate, strontium oxalate, ferrous oxalate, cerium oxalate hydrate, zinc oxalate dihydrate, nickel oxalate hydrate. + Preparation and performance test of modified CuO nanosheet and resistance sensor.

[0038] K + Effect: ①The ball milling and grinding process can effectively disperse the oxalate, and obtain potassium ion modified metal oxide nanosheet with more uniform size distribution; ②The presence of potassium ions can improve the carrier mobility of the sensing material, effectively improving the response speed and recovery speed of the sensor.

[0039] Example

[0040] K + Preparation of modified CuO nanosheet and resistance sensor:

[0041] Step (1), preparation of K +The modified CuO nanosheets used copper oxalate powder as a precursor. First, two 2g portions of copper oxalate powder were weighed into two beakers using an electronic balance. Separately, 1g of phosphorus pentoxide was weighed into a beaker as a desiccant and dehydrating agent. All three beakers were placed in a vacuum drying oven for vacuum drying to remove the water of crystallization from the oxalate. The vacuum drying conditions were 80℃ for 12 hours. After drying, two 0.1g portions of potassium chloride powder were weighed. The dried oxalate and potassium chloride powders were then poured into a mortar and ground in a 20:1 mass ratio, while simultaneously stirring thoroughly to ensure a homogeneous mixture.

[0042] Step (2): Pour the two powders into a ball mill jar containing multiple agate balls of different sizes for ball milling. There are 20 large agate balls with a diameter of 10mm and 50 small agate balls with a diameter of 6mm. The volume of the ball mill jar is 100ml.

[0043] Step (3): The ball-milled powder is poured into two crucibles and placed in a vacuum drying oven to remove the water of crystallization formed during the ball milling process. The vacuum drying temperature is 60℃ and the drying time is 6 hours. After drying, the two crucibles are placed in a muffle furnace and calcined at high temperature in air. The heating process of the muffle furnace is controlled by a program. First, the temperature is raised to 200℃ at a heating rate of 1℃ / min, and then raised to 380℃ at a heating rate of 2℃ / min. The temperature is held at 380℃ for 2 hours. After calcination, the powder is cooled to 60℃ with the furnace before being removed.

[0044] Step (4): Finally, pour the powder in the crucible into a mortar and grind it. After grinding, put the powder into a bottle and label it to complete the preparation of potassium ion modified metal oxide nanosheets.

[0045] Figure 1 For K + FESEM surface morphology image of CuO powder. From the image, we can see that K + / CuO nanomaterials are relatively uniformly distributed and have a sheet-like surface; Figure 2 , 3 For K + TEM surface morphology image of CuO powder, from which K can be clearly seen. + The size distribution of CuO nanomaterials is generally less than 50 nm. Figure 4 For K +The XRD pattern of CuO powder shows obvious diffraction peaks at diffraction angles of 32.5°, 35.5°, 38.7°, 48.8°, 53.5°, 58.3°, 61.5°, 66.1° and 68.0°. After comparison with PDF card number 48-1548, the corresponding crystal planes are (110), (111), (111), (202), (020), (202), (113), (311) and (220) respectively. Figure 5 For K + The BET specific surface area test chart of CuO powder shows that K can be obtained from the chart. + The specific surface area of ​​CuO powder reached 28.9126 m². 2 / g, with a large specific surface area.

[0046] Take 20mg K + CuO powder was placed in a beaker, and 5 ml of deionized water was added. The beaker was then placed in an ultrasonic cleaner and ultrasonicated at 54 W for 30 minutes. During ultrasonication, ice packs were added to maintain the water temperature below 30°C, yielding K. + / CuO nanosheet dispersion solution, then use a 1ml pipette to drop the solution onto the interdigitated electrode, and finally dry it at 60℃ for 2 hours to obtain K + Resistive sensors fabricated from CuO nanosheets, such as Figure 6 As shown.

[0047] Sensor performance verification

[0048] The experimental environment was 26℃ and 55%RH. The prepared sensor electrodes were connected to an LCR digital bridge, model UC2858B+. Hydraulic oil was used for the experiment. Before adding hydraulic oil, the sensor resistance decreased with increasing frequency at different frequencies. After adding hydraulic oil, the sensor resistance also decreased with increasing frequency at different frequencies, with the highest sensitivity at 100Hz, increasing from 83.7kΩ to 126.7kΩ, and a response value of 51.37%. The test results are as follows. Figure 7 As shown, this sensor has a response time of 0.5s at 100Hz, exhibiting an extremely fast response speed for detecting hydraulic oil leaks.

[0049] The sensor prepared by this invention includes metal oxide nanosheets modified with potassium ions for industrial synthesis and oil leak detection sensing materials with high sensitivity, high response, and high stability. Using these materials as the sensitive materials of the oil leak detection sensor can stably, timely, and effectively feed back the oil leak situation to the staff to avoid causing safety accidents.

[0050] As described above, this patent invention presents a method for fabricating an oil leak detection sensor based on metal oxide nanosheets. These potassium-ion-modified metal oxide nanosheets possess a large specific surface area and excellent stability, enabling highly sensitive oil leak detection at room temperature and providing effective and reliable information on oil leaks. Furthermore, the potassium-ion-modified metal oxide nanosheet material of this invention can be combined with other materials to prepare composite materials with superior performance, and can also be directly applied to sensing, catalysis, and other fields. Different types of sensors fabricated from this metal oxide nanosheet material can be used in nuclear power plants, oil and gas pipelines, oil storage tanks, and other locations, effectively detecting whether oil leaks are occurring.

[0051] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A method for fabricating an oil leak detection sensor based on metal oxide nanosheets, characterized in that, Includes the following steps: Step (1): Weigh out oxalate and potassium chloride powder in a mass ratio of 10 to 30:1 and grind them. Step (2): The uniformly ground powder is ball-milled until the oxalate is crushed and cut into flakes; Step (3): After drying the ball-milled mixed powder, it is calcined to oxidize the metal ions decomposed from oxalate into metal oxide powder, and to modify the surface of the metal oxide with potassium ions. Step (4): The metal oxide powder is further ground and then mixed with deionized water to form a liquid, wherein the mass ratio of metal oxide powder to deionized water is 2 to 6:

1. Step (5): A certain amount of mixed liquid formed in step (4) is dropped onto the interdigitated electrode. After drying, an oil leak detection sensor is obtained. In step (3), the mixed powder after ball milling is poured into a crucible and placed in a vacuum drying oven to remove the crystal water formed during ball milling; the vacuum drying temperature is 60°C and the drying time is 6 hours; the mixed powder after drying is placed in a muffle furnace and calcined at high temperature in an air environment. The calcination process is as follows: first, the temperature is raised to 200°C at a heating rate of 1°C / min, then raised to 380°C at a heating rate of 2°C / min, and held at 380°C for 2 hours. After calcination, the powder is cooled to 60°C in the furnace and then taken out.

2. The method for fabricating an oil leak detection sensor based on metal oxide nanosheets as described in claim 1, characterized in that, Before step (1), the procedure also includes: Weigh a certain amount of oxalate into a beaker, and weigh a certain amount of phosphorus pentoxide into a beaker as a desiccant and dehydrating agent. Place the beaker containing oxalate and the beaker containing phosphorus pentoxide into a vacuum drying oven for vacuum drying to remove the water of crystallization contained in oxalate. The mass ratio of oxalate to phosphorus pentoxide is 2:1, and the vacuum drying conditions are 80℃ for 12 hours.

3. The method for fabricating an oil leak detection sensor based on metal oxide nanosheets as described in claim 1, characterized in that, In step (2), the uniformly ground powder is poured into a ball mill jar containing multiple agate balls of different sizes for ball milling; there are 20 large agate balls with a diameter of 10mm and 50 small agate balls with a diameter of 6mm, and the volume of the ball mill jar is 100ml.

4. The method for fabricating an oil leak detection sensor based on metal oxide nanosheets as described in claim 3, characterized in that, In step (2), the rated speed of the ball mill is 530 rpm, the rated power is 1.5 kW, the ball milling time is 12 hours, and the ball milling jar is opened every hour during the ball milling process to stir the powder deposited at the bottom evenly before continuing the ball milling.

5. The method for fabricating an oil leak detection sensor based on metal oxide nanosheets as described in claim 1, characterized in that, In step (4), the ground metal oxide powder is mixed with deionized water, poured into a glass cup for stirring, and placed in an ultrasonic cleaner for ultrasonic dispersion. The ultrasonic cleaner has a rated power of 54W and an ultrasonic time of 30 minutes. During the ultrasonic cleaning process, ice packs are added to maintain the water temperature below 30℃.

6. The method for fabricating an oil leak detection sensor based on metal oxide nanosheets as described in claim 1, characterized in that, In step (5), a pipette is used to draw up a mixture of metal oxide powder and deionized water, and a certain amount of the mixture formed in step (4) is dropped onto the interdigitated electrode. After the drop is completed, the interdigitated electrode is placed in a drying oven for drying to complete the fixation of the material. The drying temperature is 60°C and the drying time is 2 hours.

7. The method for fabricating an oil leak detection sensor based on metal oxide nanosheets as described in claim 1, characterized in that, In step (1), the mass ratio of oxalate and potassium chloride powder is 20:1; in step (4), the mass ratio of metal oxide powder to deionized water is 4:1.

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