CN113149502A - Method for preparing reinforced concrete rust inhibitor by using eucalyptus tenuifolius leaves - Google Patents
Method for preparing reinforced concrete rust inhibitor by using eucalyptus tenuifolius leaves Download PDFInfo
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- CN113149502A CN113149502A CN202110481863.5A CN202110481863A CN113149502A CN 113149502 A CN113149502 A CN 113149502A CN 202110481863 A CN202110481863 A CN 202110481863A CN 113149502 A CN113149502 A CN 113149502A
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- eucalyptus
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B40/00—Processes, in general, for influencing or modifying the properties of mortars, concrete or artificial stone compositions, e.g. their setting or hardening ability
- C04B40/0028—Aspects relating to the mixing step of the mortar preparation
- C04B40/0039—Premixtures of ingredients
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2103/00—Function or property of ingredients for mortars, concrete or artificial stone
- C04B2103/60—Agents for protection against chemical, physical or biological attack
- C04B2103/61—Corrosion inhibitors
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- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Preventing Corrosion Or Incrustation Of Metals (AREA)
Abstract
The invention relates to the technical field of corrosion resistance and rust resistance of reinforced concrete, and particularly discloses a method for preparing a reinforced concrete rust inhibitor by using eucalyptus tenuifolius leaves, which comprises the following preparation steps of step one, drying; drying folium Eucalypti Robustae to balance weight; step two, preparing powder; grinding the eucalyptus tenuifolius leaves obtained in the step one into powder; step three, extracting; 2-4 parts of the powder collected in the step two and 6-8 parts of distilled water are stirred and mixed until the powder is uniformly mixed; keeping the obtained mixed solution at 20-30 deg.C for 22-30h, and filtering to obtain extractive solution; step four, mixing and preparing; and taking the mass of the extracting solution obtained in the third step as a reference, adding 0.8-1.2% of one or more of triethanolamine, diethanolamine or diethanol monoisopropanolamine into the extracting solution obtained in the third step, and uniformly stirring to obtain the rust inhibitor for reinforced concrete. The rust inhibitor prepared by the method is safe and environment-friendly and has a good rust inhibiting effect.
Description
Technical Field
The invention relates to the technical field of corrosion resistance and rust resistance of reinforced concrete, in particular to a method for preparing a reinforced concrete rust inhibitor by using eucalyptus tenuifolius leaves.
Background
The reinforced concrete composite structure has the advantages of simple construction method, great improvement on the compressive strength and the flexural strength of concrete, good volume stability and the like, and becomes a structural form widely applied to building engineering. When the reinforced concrete structure is in service for a long time, external erosion substances gradually invade a concrete layer to destroy a passivation film formed by the steel bars in the concrete high-alkali environment, so that the steel bars are promoted to be corroded. A large number of reinforced concrete structures are forced to be stopped due to the problem of steel bar corrosion, so that the engineering is overhauled or dismantled for reconstruction, and great economic loss is caused.
The rust inhibitor is an effective means for preventing or delaying the corrosion of the steel bar, and the rust inhibitor added in the concrete stirring process forms a protective film on the surface of the steel bar under the physical or chemical action, so that the effect of inhibiting the anode or cathode reaction of the steel bar is achieved. At present, the traditional rust inhibitor is mainly an inorganic rust inhibitor, including nitrite, molybdate and the like, and has certain toxicity. Some inorganic salts containing sodium can also promote alkali-aggregate reaction of concrete, and bring new hidden trouble to structural engineering. Therefore, the market urgently needs an environment-friendly and non-toxic rust inhibitor.
Disclosure of Invention
The invention aims to provide a method for preparing a reinforced concrete rust inhibitor by using eucalyptus tenuifolius leaves, which aims to solve the problem that the rust inhibitor in the prior art does not have the characteristics of environmental protection and no toxicity, so that the rust inhibitor brings harm to the environment and human bodies.
In order to achieve the above object, the basic scheme of the invention is as follows:
a method for preparing a reinforced concrete rust inhibitor by using eucalyptus tenuifolius leaves comprises the following preparation steps:
step one, drying; drying folium Eucalypti Robustae at 60-65 deg.C to balance weight;
step two, preparing powder; grinding the eucalyptus tenuifolius leaves obtained in the step one by drying into powder;
step three, extracting; 2-4 parts of the powder collected in the step two and 6-8 parts of distilled water are stirred and mixed until the powder is uniformly mixed; keeping the obtained mixed solution at 20-30 deg.C for 22-30h, and filtering to obtain extractive solution;
step four, mixing and preparing; and taking the mass of the extracting solution obtained in the third step as a reference, adding 0.8-1.2% of one or more of triethanolamine, diethanolamine or diethanol monoisopropanolamine into the extracting solution obtained in the third step, and uniformly stirring to obtain the rust inhibitor for reinforced concrete.
Compare the beneficial effect in prior art:
(1) when the scheme is adopted, the eucalyptus leptophylla is one of the earliest eucalyptuses introduced in China, the eucalyptuses are planted in Guangxi, Hainan, Fujian, Guangdong, Guizhou, Yunnan and the like in China in sequence after being introduced from Australia, the distribution of the eucalyptuses is extremely wide in China, the extract of the eucalyptuses is widely applied to the medical field, the application in the building field is only reported, molecules in the eucalyptus leptophylla extracting solution can spontaneously permeate in concrete and be adsorbed on the surface of a steel bar, a single-molecule protective film layer for preventing harmful compounds from permeating is formed on the surface of the steel bar, and the corrosion resistance of the steel bar can be improved.
(2) According to the scheme, the migration type rust inhibitor is formed by matching the eucalyptus tenuifolius extracting solution and triethanolamine, the rust inhibitor is mainly diffused alternately through gas and liquid phases, so that the rust inhibitor migrates from the outside of concrete to the surface of a reinforcing steel bar, the rust inhibitor has strong penetrability in the concrete, the rust inhibitor diffuses in the liquid phase through siphonage at first, and then enters the concrete through micropores and microcracks; the transmission of the organic active ingredients in the rust inhibitor can not only be diffused by capillarity and liquid phase, but also be diffused by gas phase and different modes, so that the protective film is formed at a high speed, and a good rust inhibiting effect can be achieved on the steel bar in the concrete under the condition of low addition of the rust inhibitor.
(3) The rust inhibitor prepared by the scheme is safe and nontoxic, does not harm the environment or human bodies, and is simple in preparation method, low in cost and easy for large-scale industrial production.
(4) The rust inhibitor obtained by matching the eucalyptus tenuifolius extracting solution with one or more of triethanolamine, diethanolamine or diethanol monoisopropanolamine can improve the early strength of concrete after being added into the concrete.
Further, in the first step, the eucalyptus tenuifolius leaves are placed at 15-30 ℃ for 10-24 hours before being dried; so as to stabilize the components of the eucalyptus tenuifolius leaves.
Further, the second step further comprises the step of screening the powder, and the screened powder is used in the third step.
Has the advantages that: and the sieved powder particles are smaller, so that the content of effective components in the extracting solution is favorably improved, and the solid particle residue in the rust inhibitor obtained after the step four is finished is less.
Further, a sieve with the size of 1.25mm is adopted in the screening process; by controlling the particle size of the sieved powder, the finished rust inhibitor has less solid residue.
Further, in the third step, after the powder and the distilled water are stirred and mixed, the mixed solution is subjected to ultrasonic treatment.
Further, the ultrasonic treatment time is 1-5 min; under the time control, the stirring is ensured to be uniform, and the time is saved relatively.
Further, the mixing and preparing of the step four also includes the following operations: adding 0.1-0.2% polyacrylamide into the extracting solution after one or more of triethanolamine, diethanolamine or diethanolisopropanolamine are added into the extracting solution.
Has the advantages that: solid particles which cannot be completely filtered by a filter screen may remain in the solution obtained after filtering in the third step, and after polyacrylamide is added, the viscosity of the solution can be increased, so that trace solid particles in the solution are prevented from settling, and the overall stability of the prepared rust inhibitor is further ensured.
In addition, in the concrete, the addition of polyacrylamide can also reduce the probability of occurrence of concrete bleeding phenomenon.
Furthermore, the polyacrylamide is nonionic polyacrylamide, and the molecular weight of the polyacrylamide is 400-1000 ten thousand.
Further, the reinforced concrete rust inhibitor is added when concrete is stirred, and the mixing amount of the reinforced concrete rust inhibitor relative to the volume of the concrete is as follows: 5-8Kg/m3。
Drawings
FIG. 1 is a process flow diagram of an embodiment of the invention;
FIG. 2 is a graph showing the change of the half-cell potential of the steel bar under different amounts of the corrosion inhibitor and different curing times of the concrete according to the embodiment of the present invention.
Detailed Description
The following is further detailed by way of specific embodiments:
a method for preparing a reinforced concrete rust inhibitor by using eucalyptus tenuifolius leaves comprises the following preparation steps:
step one, drying; collecting waste folium Eucalypti Robustae, standing at 15-30 deg.C for 10-24 hr, and drying in 60-65 deg.C blast drying oven to balance weight.
Step two, preparing powder; naturally cooling the eucalyptus tenuifolius leaves obtained in the step one by drying to room temperature, grinding the eucalyptus tenuifolius leaves, sieving the ground eucalyptus tenuifolius leaves by a 1.25mm sieve, and collecting powder of a sieved part.
Step three, extracting; stirring and mixing 2-4 parts by mass of the powder collected in the step two with 6-8 parts by mass of distilled water, and performing ultrasonic treatment for 1-5min to obtain a mixed solution; keeping the obtained mixture at 20-30 deg.C for 22-30h, and filtering to obtain extractive solution.
Step four, mixing and preparing; taking the mass of the extracting solution actually obtained in the third step as a reference, adding 0.8-1.2% of one or more of triethanolamine, diethanolamine or diethanol monoisopropanolamine and 0.1-0.2% of polyacrylamide (400-ten thousand molecular weight, non-ionic type) into the extracting solution obtained in the third step in sequence, and stirring for 4 hours until the mixture is uniform, thus obtaining the reinforced concrete rust inhibitor prepared by using the waste eucalyptus tenuifolia leaves.
4 specific examples were formed according to the above embodiment.
Example 1: in the first step, the standing time of the collected eucalyptus tenuifolius is controlled to be 10h, the standing temperature is controlled to be 25 ℃, and the temperature of an air-blast drying oven is controlled to be 60 ℃.
In the third step, 4 parts of powder and 6 parts of distilled water are stirred and mixed, and the ultrasonic treatment time is controlled to be 4 min.
In the third step, the temperature of the mixed solution is kept constant at 20 ℃ for 22 h.
In step four, 0.8% triethanolamine and 0.1% polyacrylamide (500 million molecular weight, nonionic) were used.
Example 2 differs from example 1 in that: in the first step, the temperature of the forced air drying oven was set to 65 ℃.
Example 3 differs from example 1 in that: in the third step, the ultrasonic treatment time is controlled to be 5 min.
Example 4 differs from example 1 in that: in the fourth step, the mass of the polyacrylamide is 0.2 percent of the mass of the extracting solution.
To verify the effectiveness of the rust inhibitor of the present invention, the following tests were performed:
the test is realized according to the following steps:
1. the experimental concrete compounding ratio is shown in table 1, the experimental concrete is prepared by stirring according to table 1, different mixing amounts of the rust inhibitor are added in the concrete stirring process, the rust inhibitor adopts the rust inhibitor of the above example 1, and the mixing amount of the reinforced concrete rust inhibitor relative to the concrete volume is as follows: 5-8Kg/m3And preparing a reinforced concrete test block with the size of 100 multiplied by 150 multiplied by 800 mm.
TABLE 1 concrete mix proportion for experiments
| Name (R) | Jinjiu cement P.O 42.5 | Fine aggregate | Coarse aggregate | Water (W) |
| Content (kg) | 360 | 746 | 1064 | 173 |
2. And (3) curing the concrete test block for 10 days in the environment with the temperature of 20 +/-2 ℃ and the humidity of more than or equal to 90%, testing the potential of the reinforcing steel bar half cell in the concrete test block under different rust inhibitor mixing amounts according to a method in DL/T5150 and 2017 hydraulic concrete test regulations, and finally obtaining the result shown in the attached figure 2.
As can be seen from FIG. 1, in the case of no curing of the concrete, the half-cell potential of the concrete reinforcing steel bar is greater than-200 mV no matter the amount of the rust inhibitor is large or small, which indicates that no corrosion occurs to the reinforcing steel bars in all the concrete blocks. For the concrete test block which is maintained for 10 days, the half-cell potential measurement values of the steel bars in the concrete test block are far less than-200 mV, which indicates that the steel bars are obviously corroded; after 10 days of maintenance, the concrete test block with the most rust inhibitor has the largest half-cell potential, which indicates that the concrete test block has the best rust inhibition effect; and with the increase of the mixing amount of the rust inhibitor, the half-cell potential of the steel bar in the concrete test block is gradually increased, which indicates that the corrosion degree of the steel bar is relieved, so that the rust inhibitor prepared by the invention plays a positive role in preventing the steel bar in the concrete from being corroded.
In addition, the rust inhibitor adopts the waste eucalyptus tenuifolius leaves, so that the waste is recycled, and the waste is changed into valuable; meanwhile, the eucalyptus tenuifolius is used as a main body, and the nontoxic triethanolamine and the polyacrylamide are added, so that the prepared rust inhibitor is nontoxic and harmless and cannot cause harm to the environment or human bodies.
In addition, the rust inhibitor prepared by the embodiment is simple in preparation method, low in cost and easy for large-scale industrial production.
The foregoing is merely an example of the present invention and common general knowledge of known specific structures and features of the embodiments is not described herein in any greater detail. It should be noted that, for those skilled in the art, without departing from the structure of the present invention, several changes and modifications can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicability of the patent. The scope of the claims of the present application shall be determined by the contents of the claims, and the description of the embodiments and the like in the specification shall be used to explain the contents of the claims.
Claims (9)
1. A method for preparing a reinforced concrete rust inhibitor by using eucalyptus tenuifolius leaves is characterized by comprising the following manufacturing steps:
step one, drying; drying folium Eucalypti Robustae at 60-65 deg.C to balance weight;
step two, preparing powder; grinding the eucalyptus tenuifolius leaves obtained in the step one by drying into powder;
step three, extracting; 2-4 parts of the powder collected in the step two and 6-8 parts of distilled water are stirred and mixed until the powder is uniformly mixed; keeping the obtained mixed solution at 20-30 deg.C for 22-30h, and filtering to obtain extractive solution;
step four, mixing and preparing; and taking the mass of the extracting solution obtained in the third step as a reference, adding 0.8-1.2% of one or more of triethanolamine, diethanolamine or diethanol monoisopropanolamine into the extracting solution obtained in the third step, and uniformly stirring to obtain the rust inhibitor for reinforced concrete.
2. The method for preparing reinforced concrete rust inhibitor by using eucalyptus tenuifolius leaves as claimed in claim 1, wherein in the first step, the eucalyptus tenuifolius leaves are placed at 15-30 ℃ for 10-24h before being dried.
3. The method for preparing reinforced concrete rust inhibitor by using eucalyptus tenuifolius leaves as claimed in claim 1, wherein the second step further comprises sieving the powder, and the sieved powder is used in the third step.
4. The method for preparing reinforced concrete rust inhibitor by using eucalyptus tenuifolius leaves as claimed in claim 3, wherein a sieve of 1.25mm is used for the sieving.
5. The method for preparing the reinforced concrete rust inhibitor by using the eucalyptus tenuifolius leaves as claimed in claim 1, wherein in the third step, after the powder and the distilled water are stirred and mixed, the mixed solution is subjected to ultrasonic treatment.
6. The method for preparing the reinforced concrete rust inhibitor by using the eucalyptus tenuifolius leaves as claimed in claim 5, wherein the ultrasonic treatment time is 1-5 min.
7. The method for preparing reinforced concrete rust inhibitor by using eucalyptus tenuifolius leaves as claimed in claim 1, wherein the mixing and formulating of the step four further comprises the following operations:
adding 0.1-0.2% polyacrylamide into the extracting solution after one or more of triethanolamine, diethanolamine or diethanolisopropanolamine are added into the extracting solution.
8. The method for preparing reinforced concrete rust inhibitor by using eucalyptus tenuifolius leaves as claimed in claim 7, wherein the polyacrylamide is non-ionic polyacrylamide, and the molecular weight of polyacrylamide is 400-1000 ten thousand.
9. The use method of the reinforced concrete rust inhibitor prepared according to any one of claims 1 to 8, characterized in that the reinforced concrete rust inhibitor is added during concrete mixing, and the relative mixing amount of the reinforced concrete rust inhibitorThe concrete volume is as follows: 5-8Kg/m3。
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001348307A (en) * | 1999-07-21 | 2001-12-18 | Oji Paper Co Ltd | Method for producing extract from eucalyptus |
| CN103304178A (en) * | 2013-05-17 | 2013-09-18 | 河海大学 | Kelp extracting solution steel bar corrosion inhibitor and application thereof |
| CN105731853A (en) * | 2016-02-29 | 2016-07-06 | 冯丽娟 | Reinforcing bar rusty retardant agent produced by vegetable waste extracts and application method of rusty retardant agent |
| CN108249800A (en) * | 2018-01-10 | 2018-07-06 | 河海大学 | A kind of plant type reinforcing steel bar corrosion inhibitor and its preparation method and application |
| CN109437636A (en) * | 2018-11-13 | 2019-03-08 | 河海大学 | A kind of reinforcing steel bar corrosion inhibitor and methods for making and using same fallen leaves using discarded plant |
-
2021
- 2021-04-30 CN CN202110481863.5A patent/CN113149502A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001348307A (en) * | 1999-07-21 | 2001-12-18 | Oji Paper Co Ltd | Method for producing extract from eucalyptus |
| CN103304178A (en) * | 2013-05-17 | 2013-09-18 | 河海大学 | Kelp extracting solution steel bar corrosion inhibitor and application thereof |
| CN105731853A (en) * | 2016-02-29 | 2016-07-06 | 冯丽娟 | Reinforcing bar rusty retardant agent produced by vegetable waste extracts and application method of rusty retardant agent |
| CN108249800A (en) * | 2018-01-10 | 2018-07-06 | 河海大学 | A kind of plant type reinforcing steel bar corrosion inhibitor and its preparation method and application |
| CN109437636A (en) * | 2018-11-13 | 2019-03-08 | 河海大学 | A kind of reinforcing steel bar corrosion inhibitor and methods for making and using same fallen leaves using discarded plant |
Non-Patent Citations (6)
| Title |
|---|
| A. M. ABDEL‑GABER ER AL: "Eucalyptus leaf extract as a eco‑friendly corrosion inhibitor for mild steel in sulfuric and phosphoric acid solutions", 《INTERNATIONAL JOURNAL OF INDUSTRIAL CHEMISTRY》 * |
| A.M.ABDEL-GABER ER.AL: ""Electrochemical Corrosion Behavior of Mild Steel in HCl and H2SO4 Solutions in Presence of Loquat Leaf Extract"", 《INTERNATIONAL JOURNAL OF ELECTROCHEMICAL SCIENCE》 * |
| M. ABDULLAH DAR: "A review: plant extracts and oils as corrosion", 《INDUSTRIAL LUBRICATION AND TRIBOLOGY》 * |
| NABIL AL-AKHRAS ET AL: "Potential use of eucalyptus leaves as green corrosion inhibitor of", 《JOURNAL OF BUILDING ENGINEERING》 * |
| 朱效荣编著: "《数字量化混凝土实用技术》", 31 May 2016, 中国建材工业出版社 * |
| 高颖波等: ""钢筋阻锈剂的应用与展望"", 《厦门大学学报（自然科学版）》 * |
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