An electrochemical method and anti-fouling system for solving titanium metal material contamination

Abstract

The present invention discloses an electrochemical method and antifouling system for solving the problem of titanium metal material fouling. A three-electrode electrochemical antifouling system is constructed with a titanium metal material that is not coated with a conductive coating as a working electrode; the titanium metal material is scanned from the open circuit potential using a linear polarization method, and the applied potential and current range are determined by the current peak; an anodic current is applied to stabilize the potential to the desired potential range to kill microorganisms attached to the surface of the titanium metal material; when the potential is monitored to exceed the warning potential, it is switched to a constant potential mode, and a negative potential is applied to remove the surface film; the above steps are repeated. This method directly utilizes the electrochemical properties of titanium and titanium alloy materials in seawater, and does not require additional conductive coating on the surface of the material to maintain a higher current density, thereby effectively killing attached microorganisms, and the potential and current used are lower than those of electrolytic antifouling, and the energy consumption is relatively low.

Description

Technical Field

[0001] The invention belongs to the technical field, and in particular relates to an electrochemical method and an anti-fouling system for solving the contamination of titanium metal materials. Background Art

[0002] Titanium alloys are ideal materials for marine engineering applications due to their excellent mechanical strength and chemical stability. They are called "marine metals" and are the most promising marine materials in the future. Although titanium and titanium alloys have strong corrosion resistance in the ocean compared to most other metal materials used in marine engineering, they are more susceptible to fouling by marine organisms (such as limeworms, algae and oysters), and the fouling is more serious. When marine organisms foul on titanium hulls, it will increase navigation resistance, resulting in reduced speed and increased fuel consumption, while marine organisms fouling in titanium pipes will block the pipes and reduce water flow. Therefore, it is necessary to effectively control the marine biofouling.

[0003] The existing methods for preventing marine organisms mainly include antifouling coating, electrolytic antifouling, ultrasonic technology, direct release of toxic materials and physical removal, among which antifouling coating and electrochemical antifouling are the two most mature methods, which have been widely used in the fields of ships, marine equipment and seawater pipelines. Electrochemical antifouling mainly focuses on electrolytic antifouling, which was first studied by Japan and the United Kingdom in the 1960s. Its main principle is to generate antifouling products through electrochemical principles to achieve the antifouling effect. There are mainly three types of systems: one is electrolysis of seawater to produce chlorine; the second is electrolytic Cu-M (Fe, Al, etc.) anode antifouling system; the third is Cu-Cl2 antifouling system. One of its disadvantages is that it requires a special electrolytic seawater antifouling device, which consumes a lot of electricity. After the antifouling products are generated by electrolysis, they are transported to the surface of the material that needs to be antifouled. It is only suitable for some seawater pipeline systems. And the latter two categories belong to anode consumption type fouling control technology, which has a limited lifespan, and the copper ions produced will pollute the environment.

[0004] The existing cathodic protection device can apply a certain cathode current to the conductive electrode through the impressed current method, and use it to provide electrons to achieve corrosion protection of marine metal materials. It is one of the commonly used devices for marine materials. Due to the limitations of marine metal materials, most marine metals cannot be directly used as working electrodes to apply anodic current. It is necessary to coat the target material with a conductive film layer, which will increase the material processing steps, change the surface properties of the material and increase costs. For some marine metal materials other than seawater pipeline systems, especially ship hulls, the cost will also increase if both the electrolytic seawater anti-fouling device and the cathodic protection device are loaded at the same time. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies of the prior art and to provide an electrochemical method and an anti-fouling system for solving the contamination of titanium metal materials, thereby solving the problems in the above-mentioned background technology.

[0006] One of the technical solutions adopted by the present invention to solve the technical problem is: providing an electrochemical method for solving the contamination of titanium metal materials, comprising the following steps:

[0007] 1) A titanium metal material without conductive coating is used as a working electrode to form a three-electrode electrochemical antifouling system with an auxiliary electrode and a reference electrode;

[0008] 2) Scanning the titanium metal material from the open circuit potential using a linear polarization method, and determining the applied potential interval and current range by the current peak; wherein the applied current is 1 / 4-1 / 12 of the peak current, and the potential interval is 0.05-0.2V ahead of the peak potential;

[0009] 3) applying an anodic current to the electrochemical antifouling system to stabilize the potential to the potential interval determined in step 2) to kill marine organisms and microorganisms attached to the surface of the titanium metal material;

[0010] 4) Setting the peak potential to move forward 0.05-0.03V as the warning potential, when the potential is detected to exceed the warning potential, switching to the constant potential mode, and applying a negative potential to remove the surface film;

[0011] 5) Repeat steps 3)-4).

[0012] In a preferred embodiment of the present invention, the titanium metal material includes titanium metal and titanium alloy.

[0013] In a preferred embodiment of the present invention, in step 2), the current range is 5-500uA / cm 2 .

[0014] In a preferred embodiment of the present invention, in step 3), the potential interval is 1.3-2.0V.

[0015] In a preferred embodiment of the present invention, in step 4), the warning potential is 2.0V.

[0016] In a preferred embodiment of the present invention, in step 4), the potential range of the negative potential is -1.2V to -0.5V.

[0017] In a preferred embodiment of the present invention, in step 4), the negative potential is applied for a period of 0.5-1 h.

[0018] The second technical solution adopted by the present invention to solve its technical problem is: providing an electrochemical anti-fouling system for solving the contamination of titanium metal materials, including a detection device, a control device, a cable and an electrode; the detection device is used to scan the titanium metal material and collect potential and current signals; the control device is connected to the detection device, and is used to control the direction, interval and time of applying the potential; the cable is used to connect the electrodes; the electrode uses a titanium metal material without a conductive coating as a working electrode, and forms a three-electrode with an auxiliary electrode and a reference electrode.

[0019] In a preferred embodiment of the present invention, it is installed on marine materials, and the marine materials include titanium hulls, marine engineering equipment and seawater pipelines.

[0020] In a preferred embodiment of the present invention, the detection device and the control device are integrated into the electrochemical workstation of the cathodic protection device.

[0021] Compared with the background technology, this technical solution has the following advantages:

[0022] 1. The present invention directly utilizes the electrochemical properties of titanium and titanium alloy materials in seawater, and does not require additional conductive coating on the surface of the material to maintain a high current density, thereby effectively killing attached microorganisms;

[0023] 2. The potential current used in the present invention is lower than that of electrolytic antifouling, and the energy consumption is low;

[0024] 3. The present invention can directly adopt the existing mature cathodic protection device for design and installation, and the purpose of the invention can be achieved by modulating the output voltage and current. There is no need to install an additional anti-pollution device, which saves costs to a great extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of the structure of the anti-fouling device of Example 1.

[0026] Figure 2 This is the linear polarization diagram of Example 1 in natural seawater.

[0027] Figure 3 This is a graph of voltage versus time after a constant current is applied to titanium metal in Example 1.

[0028] Figure 4 This is a graph of current versus time after a constant voltage is applied to titanium metal in Example 1. DETAILED DESCRIPTION

[0029] The working principle of the present invention is as follows: according to the electrochemical characteristics of titanium and titanium alloy materials in seawater, there is a small electrochemically active dissolution zone in the wider electrochemical passivation range. By applying a certain potential current in the active potential current zone, the fouling microorganisms can be directly killed through the electrochemical anode reaction, and the adhesion of the microorganisms to the titanium metal and titanium alloy can be reduced through the cathode defilming method.

[0030] Example 1

[0031] This embodiment provides an electrochemical method for solving the problem of titanium metal material contamination, comprising the following steps:

[0032] 1) Based on the existing cathodic protection device, Figure 1 As shown, a three-electrode electrochemical antifouling system is formed by using titanium metal material as a working electrode, an auxiliary electrode and a reference electrode; the three electrodes are connected to a cathodic protection device through cables, and the detection device and control device integrated in the electrochemical workstation of the cathodic protection device are used to realize the collection and control of various electrical signals;

[0033] 2) Using linear polarization scanning technology, scanning at a rate of 10mV / min from the open circuit potential, we obtain Figure 2 From the curve shown, we can see that there is an obvious current peak between 1.3 and 2.0 V, the peak current is about 100uA, and the peak potential is about 1.85V. This potential range and current peak are the potential and current reference values ​​for the subsequent electrochemical antifouling, thereby determining the applied potential to be 1.65-1.80V and the current range.

[0034] 3) A constant current of 10uA is applied to the system, and the voltage quickly reaches about 1.65V and then increases slowly;

[0035] 4) If Figure 3 As shown, when the voltage reaches 1.80V, the control device automatically switches to constant potential, and a potential of -0.8V is applied for 0.5h, and there will be a stable cathode current for surface de-filming;

[0036] 5) If Figure 4 As shown, it automatically switches to constant current mode and applies a constant current of 10uA. When the potential reaches 1.8V, it switches to constant potential again. The above process is repeated. First, the microorganisms attached to the titanium metal surface are killed by an anodic current of 10uA, and then the surface film is removed using -0.8V to achieve an anti-fouling effect.

[0037] This embodiment directly adopts the existing mature cathodic protection device for design and installation, and directly utilizes the electrochemical properties of titanium and titanium alloy materials in seawater. It does not need to apply an additional conductive coating on the surface of the material to maintain a high current density, thereby effectively killing attached microorganisms.

[0038] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some or all of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An electrochemical method for solving titanium metal material contamination, characterized in that: The steps include: 1) A titanium metal material without conductive coating is used as a working electrode to form a three-electrode electrochemical antifouling system with an auxiliary electrode and a reference electrode; 2) Scanning the titanium metal material from the open circuit potential using a linear polarization method, and determining the applied potential interval and current range by the current peak; wherein the applied current is 1 / 4-1 / 12 of the peak current, the potential interval is 0.05-0.2V ahead of the peak potential, and the current range is 5-500uA / cm 2 ; 3) applying an anodic current to the electrochemical antifouling system to stabilize the potential to the potential interval determined in step 2), wherein the potential interval is 1.3-2.0 V, so as to kill marine organisms and microorganisms attached to the surface of the titanium metal material; 4) Setting the peak potential to move forward 0.05-0.03V as the warning potential, when the potential is detected to exceed the warning potential, switching to the constant potential mode, and applying a negative potential to remove the surface film; 5) Repeat steps 3)-4).

2. The electrochemical method for solving titanium metal material contamination according to claim 1, characterized in that: The titanium metal material includes titanium metal and titanium alloy.

3. The electrochemical method for solving titanium metal material contamination according to claim 1, characterized in that: In step 4), the warning potential does not exceed 2.0V.

4. The electrochemical method for solving titanium metal material contamination according to claim 1, characterized in that: In step 4), the potential range of the negative potential is -1.2V to -0.5V.

5. The electrochemical method for solving titanium metal material contamination according to claim 1, characterized in that: In step 4), the negative potential is applied for 0.5-1 h.

6. An electrochemical anti-fouling system for solving titanium metal material contamination as used in any one of claims 1 to 5, characterized in that: It includes a detection device, a control device, a cable and an electrode; the detection device is used to scan the titanium metal material and collect potential and current signals; the control device is connected to the detection device and is used to control the direction, interval and time of applying the potential; The cable is used to connect electrodes; the electrode uses a titanium metal material not coated with a conductive coating as a working electrode, and forms three electrodes with an auxiliary electrode and a reference electrode.

7. The electrochemical anti-fouling system for solving the contamination of titanium metal materials according to claim 6, characterized in that: It is installed on marine materials, including titanium hulls, marine engineering equipment and seawater pipelines.

8. The electrochemical anti-fouling system for solving the contamination of titanium metal materials according to claim 6, characterized in that: The detection device and the control device are integrated in the electrochemical workstation of the cathode protection device.

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