CN108047795A - A kind of zinc silicate anti-corrosion paint with warning function - Google Patents

Abstract

The invention belongs to Environmental Chemistry fields, and in particular to a kind of zinc silicate anti-corrosion paint with warning function and preparation method thereof.Using " treating different things alike " preparation process, realize that carbon dots absorption in part is sandwiched on the surface of zinc silicate and part carbon dots inside zinc silicate, so as to achieve the effect that carbon dots securely modifies zinc silicate.Carbon dots modification nano anti-corrosive pigment obtained not only has good Corrosion Protection, but also carbon dots modification zinc silicate anti-corrosion paint, under the ultraviolet light of 365nm, can launch the fluorescence of blueness；When metal corrodes, and touches iron ion, Fluorescence-quenching can occur for the zinc silicate anti-corrosion paint of carbon dots modification, so as to fulfill the warning function to metal erosion.

Description

A Zinc Silicate Anticorrosion Pigment with Early Warning Function

technical field

The invention belongs to the technical field of environmental chemistry, and in particular relates to a zinc silicate anticorrosion pigment with a metal corrosion early warning function.

Background technique

Zinc silicate is an important inorganic salt, widely used in catalysis, anti-corrosion and other fields. Therefore, it is of practical significance to explore new preparation techniques and application fields.

There have been some research reports on the preparation and application of zinc silicate materials. For example, the invention with application number CN2016100155251 discloses a preparation method of zinc silicate hollow microspheres. The method firstly adds thiourea solution into zinc acetate solution, mixes evenly, and reacts hydrothermally at a temperature of 100-220° C. for 6-30 hours to prepare monodisperse zinc sulfide microspheres; dry the monodisperse zinc sulfide microspheres, Add ethanol, ammonia water and ethyl orthosilicate in sequence under stirring, and after stirring, monodisperse zinc sulfide silica core-shell structure spheres are prepared, and after drying, calcinate at 800-1000°C for 18-48h to obtain zinc silicate hollow microns ball. The invention of application number CN2015105238519 relates to a method for preparing manganese-doped zinc silicate green fluorescent powder by molten salt method, comprising the following steps: (1) using NaCl- _ZnCl mixed molten salt as the molten salt system, and adding divalent manganese chloride , silicon oxide, and grind to obtain a mixed powder; (2) react the mixed powder in the air under normal pressure conditions, 400-500 ° C molten salt for 2-6 hours; (3) after the reaction, use deionized water The molten salt is dissolved and removed, centrifuged, and dried to obtain manganese-doped zinc silicate green fluorescent powder. Application number CN2014103061543 discloses a method for synthesizing nano-zinc silicate luminescent material by using waste silicon powder hydrothermal method. The specific steps of the method are as follows: (1) Zn(CH ₃ COO) ₂ 2H ₂ O, Mn (NO ₃ ) ₂ ·4H ₂ O and cetyltrimethylammonium bromide were dissolved in deionized water, then waste silicon powder was added, stirred for 15 minutes, then sodium hydroxide or 25% ammonia water was added, stirred for 10 minutes , to obtain a mixed solution; (2) the mixed solution prepared in step (1) is put into a reactor lined with polytetrafluoroethylene, the reactor is sealed, and the temperature is put into an oven at 130-200° C. to react for 12 -48h, then take it out and cool it down to room temperature naturally, wash the product with distilled water, centrifuge and dry it naturally to obtain a zinc silicate luminescent material. Application number CN2013101667658 discloses crystallized mesoporous zinc silicate/silicon oxide composite powder and its preparation method. The composite powder has a two-dimensional hexagonal mesoporous structure. Silicon oxide composition. The preparation method is firstly preparing mesoporous silicon oxide, and then dissolving zinc inorganic salt in ethanol to prepare zinc salt solution. According to the composition of the prepared powder, the mesoporous silicon oxide is added into the zinc salt solution, wherein the molar ratio of the mesoporous silicon oxide to the zinc salt is 2-25. After fully stirring, the mesoporous silica is uniformly dispersed in the zinc salt solution, and at the same time, the stirring is continued at room temperature, and the ethanol is volatilized to obtain a powder, and then vacuum-dried and calcined to obtain a crystallized mesoporous zinc silicate/silicon oxide composite powder . Application number CN2012105881976 discloses a method for preparing zinc silicate nanomaterials, which uses amorphous nano-silicon dioxide and soluble zinc salts as raw materials, and is characterized in that it includes the following steps: step A, weighing the stoichiometric ratio of non- Crystalline nano-silicon dioxide and soluble zinc salt are prepared into a suspended aqueous solution, and the pH value is adjusted to 5-13, and stirred; step B, the suspended aqueous solution in step A is transferred into a hydrothermal reaction kettle, and heated at 160-230°C Reaction for 2-24 hours; step C, cooling the reaction system after the reaction, washing and drying the reaction product to obtain zinc silicate nanomaterials. Application number CN2011103289202 discloses a layered multi-level zinc silicate and its preparation method and application. The layered multi-level zinc silicate provided by this invention is obtained according to the method comprising the following steps: using silicon source and soluble zinc salt as raw materials, under the joint action of inorganic ammonium salt and ammonia water, through a one-step hydrothermal method The layered multi-level zinc silicate is prepared. The purpose of the invention of application number CN2010105722701 is to provide a preparation method of zinc silicate catalyst. The invention uses an alkali metal silicate aqueous solution to titrate a soluble zinc salt solution to undergo a copolymerization precipitation reaction, and the precipitate is activated, dried, pulverized and sieved. The application number CN2007100237322 discloses a micron-scale bulk silicon-based composite assembled with silicon oxide or zinc silicate nanowires and a preparation method thereof. The complex is formed on the silicon substrate with a micron-scale hollow block embedded in the silicon substrate, and an array of silicon oxide or zinc silicate nanowires is formed on the inner wall of the micron-scale hollow block; the method is to cover the silicon substrate and the surface The zinc carbonate powder with zinc powder is placed in a flowing argon atmosphere, wherein the silicon substrate is located downstream of the zinc carbonate powder covered with zinc powder on the surface, and reacted at 900-1100°C for 10-20min or 50-70min to obtain A micron-scale bulk silicon-based composite assembled with silicon oxide or zinc silicate nanowires, the purity of the zinc powder is ≥99.99wt%, the fineness is 150-250 mesh, and the purity of the zinc carbonate powder is ≥ 99.9 wt%, the fineness is 150-250 mesh, and the flowing argon atmosphere is 50-70 sccm argon. The invention of application number CN2009100037895 relates to a synthesis method of a stable polysilicate zinc polysilicate flocculant, and belongs to the field of flocculant synthesis. The preparation method is to acidify the diluted alkali metal silicate with acid, age it, raise the pH to 3-5 with the reserved alkali metal silicate solution, and then add solid inorganic zinc salt and stabilizer aluminum salt, After dissolution the pH was adjusted back to 1-3 with acid. The application number is CN2006100404227, which discloses a composite hollow sphere composed of radially closely packed zinc silicate nanowires and a preparation method thereof. Hollow spheres include zinc oxide hollow spheres, especially zinc silicate nanowires closely arranged along the radial direction in the zinc oxide hollow spheres, the length of which is 15-25 μm and the diameter is 80-100 nm; the method includes vapor deposition, especially the preparation The steps are (1) first mix the carbonate and carbon powder at a molar ratio of 2:0.8-1.2, and then cover the mixture with zinc powder with a thickness of 1-3 mm; (2) first coat the carbon powder covered with zinc powder The mixture and the silicon wafer are kept at 400-500°C in an argon atmosphere for 3-7 minutes, and then at 900-1100°C in an argon atmosphere for 1-3 hours to prepare radially closely packed zinc silicate nanoparticles. The composite hollow sphere is composed of wires, the carbonate is zinc carbonate, magnesium carbonate or manganese carbonate, and the distance between the zinc powder-coated mixture and the silicon sheet is 6-10 cm.

By comparing the existing reports on the preparation of zinc silicate materials, it can be seen that this material only protects metals in the field of anti-corrosion, but cannot give corrosion warning information, especially in the early stages of corrosion, which can be detected to avoid corrosion The occurrence of corrosion will greatly reduce the economic loss caused by corrosion. Therefore, it is of great significance to develop zinc silicate-based anti-corrosion pigments with early warning functions.

Contents of the invention

The present invention creatively designs a new type of zinc silicate anti-corrosion pigment with early warning function, adopts "one pot cooking" to realize the adsorption of some carbon points on the surface of zinc silicate and the entry of some carbon points into the crystal of zinc silicate to realize carbon Point to strong modification of zinc silicate.

The carbon dots used in the present invention are all prepared in the following manner: take 800 mg of citric acid, 50 mL of deionized water and 5 mL of ammonia water, place them in a high-pressure hydrothermal reactor, react at a constant temperature of 200 °C for 3 hours, and cool to room temperature Finally, dialyze with a 1000 Da dialysis bag for 4-6 hours until the pH of the system is 7-8 to obtain a light yellow-brown solution, which can be freeze-dried to obtain a dark green carbon dot solid.

The specific steps of the carbon dot modified zinc silicate anticorrosion pigment of the present invention are as follows: a, weigh an appropriate amount of carbon dots, and dissolve it with deionized water; b, slowly add the prepared zinc nitrate solution dropwise until the carbon dots are dissolved c. Slowly drop sodium silicate solution into the above system b under ultrasonic conditions; d. After the reaction is complete, transfer the precipitate to a hydrothermal reaction kettle, and prepare carbon dots through the "one-pot cooking" process modifying the nano-zinc silicate anticorrosion pigment; e. After the precipitate is suction-filtered and washed, then spray-dried and ground to obtain the zinc silicate anticorrosion pigment modified with carbon dots.

In the zinc silicate anticorrosion pigment modified with carbon dots in the present invention, the mass ratio of carbon dots to zinc silicate is 1:100-100:100.

A zinc silicate anticorrosion pigment modified with carbon dots in the present invention adopts "one-pot cooking" to realize the adsorption of some carbon dots on the surface of zinc silicate and the incorporation of some carbon dots into the crystal of zinc silicate, so as to achieve the effect of carbon dots on silicon Strong modification of zinc acid anti-corrosion pigments.

A zinc silicate anticorrosion pigment with an early warning function in the present invention is characterized in that the hydrothermal reaction time is 2 to 12 hours, and the hydrothermal reaction temperature is 160 to 200 ^o C.

A zinc silicate anticorrosion pigment modified with carbon dots in the present invention uses spray drying to dry the final product carbon dot modified zinc silicate anticorrosion pigment.

The present invention has the following advantages:

(1) In view of the current situation that the existing zinc silicate anti-corrosion pigments do not have the warning function, for the first time, the present invention adopts the "one-pot cooking" process to realize the firm modification of carbon dots on zinc silicate materials, and the obtained carbon-dot modified zinc silicate anti-corrosion pigments The impedance value can reach 234.6 kΩ.

(2) The carbon dot modified zinc silicate anticorrosion pigment prepared by the present invention can emit blue fluorescence under the irradiation of 365nm ultraviolet light. When the carbon dot modified zinc silicate anticorrosion pigment comes into contact with iron ions, the phenomenon of fluorescence quenching will occur, thus playing an early warning function for metal corrosion, which is of great significance for reducing the loss caused by corrosion.

(3) The carbon-dot modified zinc silicate anti-corrosion pigment prepared by the present invention has good anti-corrosion performance, simple preparation process, and does not produce three wastes pollution.

Description of drawings

Figure 1 is a transmission electron microscope image of a zinc silicate anticorrosion pigment modified with carbon dots.

Detailed ways

Through embodiment, the present invention is described further.

Example 1:

Weigh 0.22 g of carbon dots into a beaker, add 100 mL of deionized water, and after it is completely dissolved, add 200 mL of 1 mol/L zinc nitrate solution dropwise, and stir well to make it evenly mixed. Under ultrasonic working conditions, slowly add 100 mL of 1 mol/L sodium silicate solution dropwise into the beaker until the addition is complete. The precipitate was transferred to a hydrothermal reactor and reacted at 160 °C for 2 hours. After the reaction is finished, filter and wash the precipitate with suction and then spray dry to obtain the carbon dot modified zinc silicate anticorrosion pigment, which can emit blue fluorescence under the irradiation of 365nm ultraviolet light. After the anti-corrosion coating is made, the impedance value of the paint film reaches 150.3 kΩ.

Example 2:

Weigh 2.2 g of carbon dots into a beaker, add 100 mL of deionized water, and after it is completely dissolved, add 200 mL of 1 mol/L zinc nitrate solution dropwise, and stir well to make it evenly mixed. Under ultrasonic working conditions, slowly add 100 mL of 1 mol/L sodium silicate solution dropwise into the beaker until the addition is complete. The precipitate was transferred to a hydrothermal reactor and reacted at 160 °C for 12 hours. After the reaction is finished, filter and wash the precipitate with suction and then spray dry to obtain the carbon dot modified zinc silicate nano anticorrosion pigment. The anticorrosion pigment can emit blue fluorescence under the irradiation of 365 nm ultraviolet light. After the anti-corrosion coating is made, the impedance value of the paint film reaches 167.1 kΩ.

Example 3:

Weigh 22.0 g of carbon dots into a beaker, add 100 mL of deionized water, and after it is completely dissolved, add 200 mL of 1 mol/L zinc nitrate solution dropwise, and stir well to make it evenly mixed. Under ultrasonic working conditions, slowly add 100 mL of 1 mol/L sodium silicate solution dropwise into the beaker until the addition is complete. The precipitate was transferred to a hydrothermal reactor and reacted at 160 °C for 8 hours. After the reaction is finished, filter and wash the precipitate with suction and then spray dry to obtain the carbon dot modified zinc silicate nano anticorrosion pigment. The anticorrosion pigment can emit blue fluorescence under the irradiation of 365 nm ultraviolet light. After the anti-corrosion coating is made, the impedance value of the paint film reaches 234.6 kΩ.

Example 4:

Weigh 11.0 g of carbon dots in a beaker, add 100 mL of deionized water, and after it is completely dissolved, add 200 mL of 1 mol/L zinc nitrate solution dropwise, and stir well to make it evenly mixed. Under ultrasonic working conditions, slowly add 100 mL of 1 mol/L sodium silicate solution dropwise into the beaker until the addition is complete. The precipitate was transferred to a hydrothermal reactor and reacted at 200 °C for 6 hours. After the reaction is finished, filter and wash the precipitate with suction and then spray dry to obtain the carbon dot modified zinc silicate nano anticorrosion pigment. The anticorrosion pigment can emit blue fluorescence under the irradiation of 365nm ultraviolet light. After the anti-corrosion coating is made, the impedance value of the paint film reaches 185.6 kΩ.

Claims (3)

1. a kind of zinc silicate anti-corrosion paint with warning function, it is characterised in that in the zinc silicate anti-corrosion paint component carbon dots and The mass ratio of zinc silicate is 1:100~100:100, it is as follows：A, appropriate carbon dots is weighed, with deionized water to it It is dissolved；B, prepared zinc nitrate solution is slowly added dropwise into the carbon dots solution dissolved；C, item is disperseed in ultrasonic wave Under part sodium silicate solution is slowly dropped into above-mentioned b systems；D, after complete reaction, precipitation is transferred in hydrothermal reaction kettle, Carbon dots modification zinc silicate corrosion-inhibiting pigment, some carbon in the step are produced by using simple and convenient " treating different things alike " technique Point can be adsorbed on the surface of zinc silicate, some carbon dots can enter the crystals of zinc silicate, so as to fulfill carbon dots to silicon The secured modification of sour zinc；E, by after the precipitation filtering and washing obtained in Step d, then be spray-dried, it is polished obtain having it is pre- The carbon dots modification zinc silicate anti-corrosion paint of alert function, carbon dots modification zinc silicate anti-corrosion paint, in the ultraviolet light of 365nm Under, blue fluorescence can be launched；When touching iron ion, it may occur that Fluorescence-quenching, so as to fulfill rotten to metal The warning function of erosion.

2. a kind of zinc silicate anti-corrosion paint with warning function, it is characterised in that when the time of hydro-thermal reaction is 2 ~ 12 small.

3. a kind of zinc silicate anti-corrosion paint with warning function, it is characterised in that the temperature of hydro-thermal reaction is 160 ~ 200^oC。