CN-122016772-A - Test paper for rapidly detecting content of phosphoric acid in asphalt, and preparation method and application method thereof

CN122016772ACN 122016772 ACN122016772 ACN 122016772ACN-122016772-A

Abstract

The invention discloses a rapid test paper for the content of phosphoric acid in asphalt, a preparation method and a use method thereof, wherein the rapid test paper for the content of phosphoric acid in asphalt comprises a base layer, a leaching layer, a reaction layer and a color development layer which are sequentially laminated from bottom to top; the leaching layer is adsorbed with dilute nitric acid, the reaction layer is obtained by impregnating and drying a mixed solution of ammonium molybdate and ascorbic acid, and the color development layer is obtained by impregnating and drying a sodium citrate solution. By implementing the invention, the content of phosphoric acid in asphalt can be rapidly and stably detected, and data support is provided for subsequent asphalt performance research.

Inventors

Kuang qiang
Lin Mengmiao
SHAN NAN
MOU TAO
LI YUKUN
Chen Tuhao
ZENG WANGQIANG
OU CANHUI
LI CHENXIAO
LI YAOHUI

Assignees

佛山市公路桥梁工程监测站有限公司
海南公路建设项目管理有限公司
海南路桥工程有限公司

Dates

Publication Date: 20260512
Application Date: 20260113

Claims (10)

1. A test paper for rapidly detecting the content of phosphoric acid in asphalt is characterized by comprising a base layer, an extraction layer, a reaction layer and a color development layer which are sequentially stacked from bottom to top, wherein dilute nitric acid is adsorbed on the extraction layer, the reaction layer is obtained by dipping and drying a mixed solution of ammonium molybdate and ascorbic acid, and the color development layer is obtained by dipping and drying a sodium citrate solution.
2. The rapid test paper for detecting the content of phosphoric acid in asphalt according to claim 1, wherein the leaching layer is absorbent cotton fibers adsorbed with dilute nitric acid, the porosity of the absorbent cotton fibers is 75% -85%, the concentration of the dilute nitric acid is 0.3-0.6 mol/L, and the adsorption amount is 0.15-0.25 mL/piece.
3. The rapid test paper for detecting the content of phosphoric acid in asphalt according to claim 1, wherein the reaction layer is quantitative filter paper which is immersed in a mixed solution of ammonium molybdate and ascorbic acid and dried, the pore diameter of the quantitative filter paper is 3-5 μm, the pH of the mixed solution of ammonium molybdate and ascorbic acid is 1.2-1.5, the mass fraction of ammonium molybdate in the mixed solution is 1.5-2.5%, and the mass fraction of ascorbic acid is 0.5-1.5%.
4. The rapid test paper for detecting the content of phosphoric acid in asphalt according to claim 1, wherein the color development layer is quantitative filter paper which is immersed in sodium citrate solution and dried, the pore diameter of the quantitative filter paper is 1-3 μm, and the mass fraction of the sodium citrate solution is 0.25-0.75%.
5. The rapid test paper for detecting the content of phosphoric acid in asphalt according to claim 1, wherein holes are formed in the base layer, and the leaching layer completely covers the holes.
6. The rapid test strip for detecting the content of phosphoric acid in asphalt according to claim 1, further comprising a protective layer covering the base layer, the leaching layer, the reaction layer and the color development layer; The protective layer is a transparent polyethylene film, and the thickness of the protective layer is 0.01 mm-0.03 mm; the thickness of the base layer is 0.2 mm-0.4 mm.
7. A method for preparing the test paper for rapidly detecting the content of phosphoric acid in asphalt according to any one of claims 1 to 6, comprising the following steps: soaking the leaching layer material in dilute nitric acid for 4-6 min, and extruding excessive dilute nitric acid to obtain the leaching layer; adding nitric acid into water, regulating the pH value to be 1.2-1.5, and respectively adding ammonium molybdate and ascorbic acid to obtain an ammonium molybdate and ascorbic acid mixed solution, soaking a reaction layer material in the ammonium molybdate and ascorbic acid mixed solution for 12-20 min, and carrying out forced air drying at 50-70 ℃ for 2-4 h to obtain the reaction layer; Soaking a color development layer material in a sodium citrate solution for 8-12 min, and carrying out forced air drying at 50-70 ℃ for 1-3 h to obtain the color development layer; And overlapping the base layer, the leaching layer, the reaction layer and the color development layer to obtain the test paper for rapidly detecting the phosphoric acid content in the asphalt.
8. The method for preparing a test paper for rapidly detecting the content of phosphoric acid in asphalt according to claim 7, wherein holes are formed in the base layer, and the leaching layer is completely covered on the holes; and covering the protective layer on the base layer, the leaching layer, the reaction layer and the color development layer by adopting a hot-pressing lamination process.
9. A method for using the rapid test paper for detecting the content of phosphoric acid in asphalt according to any one of claims 1 to 6, which is characterized by comprising the following steps: sampling to obtain an asphalt sample; the leaching layer of the rapid test paper for the content of phosphoric acid in the asphalt is tightly attached to an asphalt sample, and 25-35 s are pressed; placing the test paper for rapidly detecting the phosphoric acid content in the asphalt horizontally for 4-7 min; And observing the color of the color development layer to obtain the phosphoric acid content range.
10. The method of claim 9, wherein if the color of the color layer is almost colorless or bluish, the phosphoric acid content is less than 0.05%; if the color of the color development layer is light blue, the content of phosphoric acid is more than or equal to 0.05 percent and less than 0.1 percent; If the color of the color-developing layer is medium blue, the content of phosphoric acid is more than or equal to 0.1% and less than 0.5%; If the color of the color development layer is dark blue, the content of phosphoric acid is more than or equal to 0.5% and less than 1%; If the color of the color-developing layer is ink blue, the phosphoric acid content is more than 1%.

Description

Test paper for rapidly detecting content of phosphoric acid in asphalt, and preparation method and application method thereof Technical Field The invention relates to the technical field of highway engineering material detection, in particular to rapid detection test paper for the content of phosphoric acid in asphalt, and a preparation method and a use method thereof. Background The sources of phosphoric acid components (mainly phosphate radicals) in asphalt mainly comprise raw material impurities, additive residues and the like, and in order to explore the potential influence of the phosphoric acid content in the asphalt on the core performances such as the adhesiveness, the ageing resistance and the interface action with aggregates of the asphalt, a detection method of the phosphoric acid content in the asphalt needs to be established. The existing detection methods of the phosphoric acid content mainly comprise a molybdenum blue spectrophotometry, an ion chromatography method, a kit detection method and the like. The method comprises the steps of carrying out high-temperature ashing at 550-600 ℃ to destroy an organic matrix, wherein asphalt is a high-viscosity and high-carbon-content organic system, phosphate radical is wrapped by carbonized residues in the ashing process, the extraction rate of the phosphate radical is only 30-50%, the detection stability is poor, carrying out wet digestion on the asphalt by using nitric acid and perchloric acid in the ion chromatography, colloid and asphaltene in the asphalt are easy to react with perchloric acid severely, the risk of bumping exists, residual organic impurities in the digested solution pollute a chromatographic column, the maintenance cost of the instrument is increased, meanwhile, aromatic possibly existing in the asphalt can interfere the detection result, the quantitative deviation can reach +/-30%, the industrial phosphate radical rapid detection kit (such as a general kit of Hash company) is mainly used for water samples or low-viscosity industrial samples, the high-viscosity asphalt samples are difficult to be fully mixed with the kit, the reagent cannot penetrate the asphalt organic matrix to extract the phosphate radical, and the actual reference value of the detection result is low. Disclosure of Invention The invention aims to solve the technical problem of providing the test paper for rapidly detecting the content of phosphoric acid in asphalt, the preparation method and the use method thereof, which can rapidly and stably detect the content of phosphoric acid in asphalt and provide data support for subsequent asphalt performance research. In order to solve the problems, the invention discloses a test paper for rapidly detecting the content of phosphoric acid in asphalt, which comprises a base layer, an extraction layer, a reaction layer and a color development layer which are sequentially stacked from bottom to top, wherein dilute nitric acid is adsorbed on the extraction layer, the reaction layer is immersed and dried by a mixed solution of ammonium molybdate and ascorbic acid, and the color development layer is immersed and dried by a sodium citrate solution. As improvement of the technical scheme, the leaching layer is absorbent cotton fibers adsorbed with dilute nitric acid, the porosity of the absorbent cotton fibers is 75% -85%, the concentration of the dilute nitric acid is 0.3-0.6 mol/L, and the adsorption quantity is 0.15-0.25 mL/piece. According to the technical scheme, the reaction layer is quantitative filter paper which is immersed in a mixed solution of ammonium molybdate and ascorbic acid and dried, the aperture of the quantitative filter paper is 3-5 microns, the pH value of the mixed solution of ammonium molybdate and ascorbic acid is 1.2-1.5, the mass fraction of ammonium molybdate in the mixed solution is 1.5-2.5%, and the mass fraction of ascorbic acid is 0.5-1.5%. As improvement of the technical scheme, the color developing layer is quantitative filter paper which is immersed in sodium citrate solution and dried, the aperture of the quantitative filter paper is 1-3 mu m, and the mass fraction of the sodium citrate solution is 0.25-0.75%. As an improvement of the technical scheme, holes are formed in the base layer, and the leaching layer completely covers the holes. As an improvement of the technical scheme, the rapid test paper for the content of phosphoric acid in asphalt also comprises a protective layer, wherein the protective layer covers the base layer, the leaching layer, the reaction layer and the color development layer; The protective layer is a transparent polyethylene film, and the thickness of the protective layer is 0.01 mm-0.03 mm; the thickness of the base layer is 0.2 mm-0.4 mm. Correspondingly, the invention also discloses a preparation method for preparing the rapid test paper for detecting the content of phosphoric acid in asphalt, which comprises the following steps: soaking the leaching layer mate