Method for analyzing the reactivity of fly ash / slag for geopolymer

Abstract

The present application relates to a kind of fly ash / slag reactivity analysis method for geopolymer, belong to geopolymer technical field.To solve the problem that existing reactivity analysis method is not accurate enough and application range is limited to fly ash, the present application provides a kind of fly ash / slag reactivity analysis method for geopolymer, the mass ratio of SiO2, Al2O3, MgO and CaO existing in crystalline phase and amorphous phase is obtained by XRF analysis to the material to be measured;The mass ratio of SiO2, Al2O3, MgO and CaO existing in crystalline phase is obtained by XRD analysis to the material to be measured;The mass ratio of SiO2, Al2O3, MgO and CaO existing in amorphous phase is calculated;Fly ash / slag activity index is obtained by bringing it into formula.The analysis method of the present application has higher accuracy and wider application range, and the detection and analysis process is faster and simpler, easy to promote.

Description

Technical Field

[0001] This invention belongs to the field of geopolymer technology, and particularly relates to a method for analyzing the reactivity of geopolymers using fly ash / slag. Background Technology

[0002] Fly ash and slag are industrial byproducts from thermal power generation, metal smelting, and other industrial activities. Improper handling can easily lead to soil and water pollution. However, these byproducts, under the action of alkaline or acidic activators, have the potential to replace cement as a gelling material. Alkaline activators can enhance the activity of fly ash, slag, and other powders, leading to their polymerization into geopolymer concrete with a three-dimensional Si, Al, and O network structure. Compared to ordinary cement, geopolymer concrete has advantages such as lower heat of hydration, better freeze-thaw resistance, and stronger corrosion resistance.

[0003] However, geopolymerization is complex and variable. The reactivity of fly ash or slag during the polymerization process determines the degree of geopolymerization. Therefore, accurately and quantitatively determining the reactivity of fly ash or slag in geopolymers plays an important role in predicting the macroscopic mechanical properties and durability of geopolymers.

[0004] The material structure of fly ash and slag is mainly composed of crystalline and amorphous phases, and studies have found that their activity is primarily determined by the amorphous phase composition. Existing methods for evaluating fly ash activity use the product of the glass content and the specific surface area of ​​the fly ash to assess its reactivity. The glass content is measured using a calibration curve method or a profile fitting method based on powder X-ray diffraction. This method assumes that the fly ash particles are spherical and calculates the specific surface area based on the particle size distribution. The calculation process is complex, and the activity calculation formula only reflects the total content of the amorphous phase. It is not precise enough for analyzing the activity of fly ash in geopolymerization reactions, and its application is limited to fly ash. Summary of the Invention

[0005] To address the shortcomings of existing reactivity analysis methods, which are not precise enough and whose application is limited to fly ash, this invention provides a reactivity analysis method for fly ash / slag used in geopolymers.

[0006] The technical solution of the present invention:

[0007] A method for analyzing the reactivity of geopolymers with fly ash / slag includes the following steps:

[0008] Step 1: Perform XRF analysis on the fly ash or slag material to be tested, and calculate the mass percentage ω of all SiO2, Al2O3, MgO and CaO existing in crystalline and amorphous phases in the material. 总SiO2 ω 总Al2O3 ω总MgO ω 总CaO ;

[0009] Step 2: After adding an internal standard to the test material, perform XRD analysis and fit the XRD curve to obtain the mass percentages of amorphous and crystalline phase components in the test material. Calculate the mass percentages ω of SiO2, Al2O3, MgO, and CaO existing in crystalline phases in the test material. 晶相SiO2 ω 晶相Al2O3 ω 晶相MgO ω 晶相CaO ;

[0010] Step 3: Calculate the mass percentage ω of SiO2, Al2O3, MgO, and CaO existing in amorphous phase in the material to be tested. 非晶相SiO2 ω 非晶相Al2O3 ω 非晶相MgO ω 非晶相CaO ;

[0011] Step 4: Calculate the activity index using the formula K = (ω 非晶相CaO +ω 非晶相MgO +ω 非晶相Al2O3 ) / ω 非晶相SiO2 Calculate the activity index of the material to be tested. The higher the activity index, the better the reactivity.

[0012] Furthermore, the internal standard mentioned in step two is zinc oxide, and the amount of zinc oxide added is 15% of the weight of the material to be tested.

[0013] Furthermore, in step two, the analysis software used to fit the XRD curve was TOPAS software.

[0014] Furthermore, step two XRD analysis revealed that the substances present in the fly ash sample in crystalline form were mullite and quartz.

[0015] Furthermore, the mullite is calculated according to the molecular formula 2.4Al2O3·1.2SiO2; the quartz ratio is calculated according to the molecular formula SiO2. The total mass percentage of SiO2 in mullite and quartz and the mass percentage of Al2O3 in mullite are obtained by calculation.

[0016] Furthermore, step two XRD analysis revealed that the substance present in the slag in crystalline form was gypsum.

[0017] Furthermore, the gypsum is calculated according to the molecular formula CaSO4·2H2O; the mass percentage of CaO in the gypsum is obtained by calculation.

[0018] Furthermore, in step three, ω 非晶相SiO2 ω 非晶相Al2O3 ω 非晶相MgO ω非晶相CaO The calculation formula is:

[0019] ω 非晶相SiO2 =ω 总SiO2 -ω 晶相SiO2 ;

[0020] ω 非晶相Al2O3 =ω 总Al2O3 -ω 晶相Al2O3 ;

[0021] ω 非晶相MgO =ω 总MgO -ω 晶相MgO ;

[0022] ω 非晶相CaO =ω 总CaO -ω 晶相CaO .

[0023] The beneficial effects of this invention are:

[0024] The reactivity analysis method for fly ash / slag used in geopolymers provided by this invention takes the different contributions of various amorphous phase elements to the geopolymerization reactivity as its starting point, focusing on the influence of the amorphous phase contents of Si, Al, Mg, and Ca on the geopolymerization reactivity of fly ash or slag. This invention incorporates the amorphous phase contents of SiO2, Al2O3, MgO, and CaO in fly ash or slag into the reactivity index formula, more accurately and quantitatively analyzing the reactivity of fly ash or slag during geopolymerization. The fitting variance R of this formula is... 2 The accuracy of the analytical method of this invention is 0.97, which proves that the method has high accuracy and provides strong support for the construction and durability prediction of geopolymers prepared from fly ash or slag.

[0025] The reactivity analysis method for fly ash / slag used in geopolymers provided by this invention has a wider range of applications, and it does not require specific surface area testing. The detection and analysis process is faster and simpler, making it easier to promote and apply. Attached Figure Description

[0026] Figure 1 The graph shows the linear fitting results of the activity index and compressive strength after 28 days of alkali activation obtained by analysis and calculation of the test materials in Examples 1-8. Detailed Implementation

[0027] The technical solution of the present invention will be further described below with reference to embodiments, but it is not limited thereto. Any modifications or equivalent substitutions to the technical solution of the present invention without departing from the spirit and scope of the technical solution of the present invention should be covered within the protection scope of the present invention. In the following embodiments, the process equipment or apparatus not specifically specified are all conventional equipment or apparatus in the art. Unless otherwise specified, the raw materials used in the embodiments of the present invention are all commercially available; unless otherwise specified, the technical means used in the embodiments of the present invention are all conventional means well known to those skilled in the art.

[0028] Example 1

[0029] This embodiment provides a method for analyzing the reactivity of fly ash used in geopolymers and applies it to the analysis of fly ash materials.

[0030] The fly ash used in this embodiment was purchased from Yiran Mineral Products Processing Plant in Lingshou County, Hebei Province, and is marked as FA1.

[0031] The reactivity analysis method in this embodiment includes the following steps:

[0032] Step 1: Perform XRF analysis on the fly ash material to be tested, and calculate the mass percentage ω of all SiO2, Al2O3, MgO and CaO existing in crystalline and amorphous phases in the material. 总SiO2 =50.3167%, ω 总Al2O3 =32.61%, ω 总MgO =0.55524%, ω 总CaO =5.46961%;

[0033] Step 2: After adding 15% (by weight) of the internal standard zinc oxide to the test material, XRD analysis was performed. The XRD curves were fitted using TOPAS analysis software to obtain the mass percentages of amorphous and crystalline components in the test material. In the fly ash sample, the crystalline components were mullite and quartz. Mullite was calculated using the molecular formula 2,4Al₂O₃·1,2SiO₂; quartz was calculated using the molecular formula SiO₂. The total mass percentage of SiO₂ in mullite and quartz, and the mass percentage of Al₂O₃ in mullite were calculated.

[0034] ω 晶相SiO2 =10.8387%, ω 晶相Al2O3 =24.7713%, ω 晶相MgO =0%, ω 晶相CaO =0%;

[0035] Step 3: The mass percentages of SiO2, Al2O3, MgO, and CaO existing in amorphous phase in the material to be tested are calculated:

[0036] The mass percentage of SiO2 present in amorphous phase in the material under test:

[0037] ω 非晶相SiO2 =ω 总SiO2 -ω 晶相SiO2 =50.3167% - 10.8387% = 39.478%;

[0038] The mass percentage of Al2O3 existing in the amorphous phase in the tested material:

[0039] ω 非晶相Al2O3 =ω 总Al2O3 -ω 晶相Al2O3 =32.61% - 24.7713% = 7.8387%;

[0040] The mass percentage of MgO in the amorphous phase in the tested material:

[0041] ω 非晶相MgO =ω 总MgO -ω 晶相MgO =0.55524% - 0% = 0.55524%;

[0042] The mass percentage of CaO present in the amorphous phase in the tested material:

[0043] ω 非晶相CaO =ω 总CaO -ω 晶相CaO =5.46961% - 0% = 5.46961%.

[0044] Step 4: Substitute the mass percentages of SiO2, Al2O3, MgO, and CaO existing in amorphous phases into the activity index calculation formula K = (ω 非晶相CaO +ω 非晶相MgO +ω 非晶相Al2O3 ) / ω 非晶相SiO2 Calculate the activity index of fly ash FA1:

[0045] K FA1 = (5.46961 + 0.5524 + 7.8387) / 39.478 = 0.35.

[0046] Example 2

[0047] This embodiment provides a method for analyzing the reactivity of fly ash used in geopolymers and applies it to the analysis of fly ash materials.

[0048] The fly ash used in this embodiment was purchased from Yaoxin Mineral Products Processing Plant in Lingshou County, Hebei Province, and is marked as FA2.

[0049] Step 1: Perform XRF analysis on the fly ash material to be tested, and calculate the mass percentage ω of all SiO2, Al2O3, MgO and CaO existing in crystalline and amorphous phases in the material. 总SiO2 =52.5613%, ω 总Al2O3 =31.661%, ω 总MgO =0.30914%, ω 总CaO =4.08605%;

[0050] Step 2: After adding 15% (by weight) of the internal standard zinc oxide to the test material, XRD analysis was performed. The XRD curves were fitted using TOPAS analysis software to obtain the mass percentages of amorphous and crystalline components in the test material. In the fly ash sample, the crystalline components were mullite and quartz. Mullite was calculated using the molecular formula 2,4Al₂O₃·1,2SiO₂; quartz was calculated using the molecular formula SiO₂. The total mass percentage of SiO₂ in mullite and quartz, and the mass percentage of Al₂O₃ in mullite were calculated.

[0051] ω 晶相SiO2 =16.2388%, ω 晶相Al2O3 =30.5412%, ω 晶相MgO =0%, ω 晶相CaO =0%;

[0052] Step 3: The mass percentages of SiO2, Al2O3, MgO, and CaO existing in amorphous phase in the material to be tested are calculated:

[0053] The mass percentage of SiO2 present in amorphous phase in the material under test:

[0054] ω 非晶相SiO2 =ω 总SiO2 -ω 晶相SiO2 =52.5613% - 16.2388% = 36.3225%;

[0055] The mass percentage of Al2O3 existing in the amorphous phase in the tested material:

[0056] ω 非晶相Al2O3 =ω 总Al2O3 -ω 晶相Al2O3 =31.661% - 30.5412% = 1.1198%;

[0057] The mass percentage of MgO in the amorphous phase in the tested material:

[0058] ω 非晶相MgO =ω 总MgO -ω 晶相MgO=0.30914% - 0% = 0.30914%;

[0059] The mass percentage of CaO present in the amorphous phase in the tested material:

[0060] ω 非晶相CaO =ω 总CaO -ω 晶相CaO =4.08605% - 0% = 4.08605%.

[0061] Step 4: Substitute the mass percentages of SiO2, Al2O3, MgO, and CaO existing in amorphous phases into the activity index calculation formula K = (ω 非晶相CaO +ω 非晶相MgO +ω 非晶相Al2O3 ) / ω 非晶相SiO2 Calculate the activity index of fly ash FA2:

[0062] K FA2 = (4.08605 + 0.30914 + 1.1198) / 36.3225 = 0.15.

[0063] Example 3

[0064] This embodiment provides a method for analyzing the reactivity of fly ash used in geopolymers and applies it to the analysis of fly ash materials.

[0065] The fly ash used in this embodiment was purchased from Shijiazhuang Yunjia Trading Co., Ltd., and is marked as FA3.

[0066] The reactivity analysis method in this embodiment includes the following steps:

[0067] Step 1: Perform XRF analysis on the fly ash material to be tested, and calculate the mass percentage ω of all SiO2, Al2O3, MgO and CaO existing in crystalline and amorphous phases in the material. 总SiO2 =53.6349%, ω 总Al2O3 =27.3491%, ω 总MgO =0.50904%, ω 总CaO =6.01468%;

[0068] Step 2: After adding 15% (by weight) of the internal standard zinc oxide to the test material, XRD analysis was performed. The XRD curves were fitted using TOPAS analysis software to obtain the mass percentages of amorphous and crystalline components in the test material. In the fly ash sample, the crystalline components were mullite and quartz. Mullite was calculated using the molecular formula 2,4Al₂O₃·1,2SiO₂; quartz was calculated using the molecular formula SiO₂. The total mass percentage of SiO₂ in mullite and quartz, and the mass percentage of Al₂O₃ in mullite were calculated.

[0069] ω 晶相SiO2 =8.56597%, ω 晶相Al2O3 =14.614%, ω 晶相MgO =0%, ω 晶相CaO =0.05211%;

[0070] Step 3: The mass percentages of SiO2, Al2O3, MgO, and CaO existing in amorphous phase in the material to be tested are calculated:

[0071] The mass percentage of SiO2 present in amorphous phase in the material under test:

[0072] ω 非晶相SiO2 =ω 总SiO2 -ω 晶相SiO2 =53.6349% - 8.56597% = 45.06893%;

[0073] The mass percentage of Al2O3 existing in the amorphous phase in the tested material:

[0074] ω 非晶相Al2O3 =ω 总Al2O3 -ω 晶相Al2O3 =27.3491% - 14.614% = 12.7351%;

[0075] The mass percentage of MgO in the amorphous phase in the tested material:

[0076] ω 非晶相MgO =ω 总MgO -ω 晶相MgO =0.50904% - 0% = 0.50904%;

[0077] The mass percentage of CaO present in the amorphous phase in the tested material:

[0078] ω 非晶相CaO =ω 总CaO -ω 晶相CaO =6.01468% - 0.05211% = 5.96257%.

[0079] Step 4: Substitute the mass percentages of SiO2, Al2O3, MgO, and CaO existing in amorphous phases into the activity index calculation formula K = (ω 非晶相CaO +ω 非晶相MgO +ω 非晶相Al2O3 ) / ω 非晶相SiO2 Calculate the activity index of fly ash FA3:

[0080] K FA3 = (5.96257 + 0.50904 + 12.7351) / 45.06893 = 0.43.

[0081] Example 4

[0082] This embodiment provides a method for analyzing the reactivity of fly ash used in geopolymers and applies it to the analysis of fly ash materials.

[0083] The fly ash used in this embodiment was purchased from Yongqi Mineral Products Co., Ltd. in Lingshou County, Hebei Province, and is marked as FA4.

[0084] The reactivity analysis method in this embodiment includes the following steps:

[0085] Step 1: Perform XRF analysis on the fly ash material to be tested, and calculate the mass percentage ω of all SiO2, Al2O3, MgO and CaO existing in crystalline and amorphous phases in the material. 总SiO2 =50.5856%, ω 总Al2O3 =31.7799%, ω 总MgO =0.39754%, ω 总CaO =7.15184%;

[0086] Step 2: After adding 15% (by weight) of the internal standard zinc oxide to the test material, XRD analysis was performed. The XRD curves were fitted using TOPAS analysis software to obtain the mass percentages of amorphous and crystalline components in the test material. In the fly ash sample, the crystalline components were mullite and quartz. Mullite was calculated using the molecular formula 2,4Al₂O₃·1,2SiO₂; quartz was calculated using the molecular formula SiO₂. The total mass percentage of SiO₂ in mullite and quartz, and the mass percentage of Al₂O₃ in mullite were calculated.

[0087] ω 晶相SiO2 =7.22522%, ω 晶相Al2O3 =19.4648%, ω 晶相MgO =0%, ω 晶相CaO =0%;

[0088] Step 3: The mass percentages of SiO2, Al2O3, MgO, and CaO existing in amorphous phase in the material to be tested are calculated:

[0089] The mass percentage of SiO2 present in amorphous phase in the material under test:

[0090] ω 非晶相SiO2 =ω 总SiO2 -ω 晶相SiO2 =50.5856% - 7.22522% = 43.36038%;

[0091] The mass percentage of Al2O3 existing in the amorphous phase in the tested material:

[0092] ω 非晶相Al2O3 =ω 总Al2O3 -ω 晶相Al2O3 =31.7799% - 19.4648% = 12.3151%;

[0093] The mass percentage of MgO in the amorphous phase in the tested material:

[0094] ω 非晶相MgO =ω 总MgO -ω 晶相MgO =0.39754% - 0% = 0.39754%;

[0095] The mass percentage of CaO present in the amorphous phase in the tested material:

[0096] ω 非晶相CaO =ω 总CaO -ω 晶相CaO =7.15184% - 0% = 7.15184%.

[0097] Step 4: Substitute the mass percentages of SiO2, Al2O3, MgO, and CaO existing in amorphous phases into the activity index calculation formula K = (ω 非晶相CaO +ω 非晶相MgO +ω 非晶相Al2O3 ) / ω 非晶相SiO2 Calculate the activity index of fly ash FA4:

[0098] K FA4 = (7.15184 + 0.39754 + 12.3151) / 43.36038 = 0.46.

[0099] Example 5

[0100] This embodiment provides a method for analyzing the reactivity of fly ash used in geopolymers and applies it to the analysis of fly ash materials.

[0101] The fly ash used in this embodiment was purchased from Shengyun Mineral Products Processing Plant in Lingshou County, Hebei Province, and is marked as FA5.

[0102] The reactivity analysis method in this embodiment includes the following steps:

[0103] Step 1: Perform XRF analysis on the fly ash material to be tested, and calculate the mass percentage ω of all SiO2, Al2O3, MgO and CaO existing in crystalline and amorphous phases in the material. 总SiO2 =47.57%, ω 总Al2O3 =15.0596%, ω 总MgO =2.49973%, ω 总CaO =19.0716%;

[0104] Step 2: After adding 15% (by weight) of the internal standard zinc oxide to the test material, XRD analysis was performed. The XRD curves were fitted using TOPAS analysis software to obtain the mass percentages of amorphous and crystalline components in the test material. In the fly ash sample, the crystalline components were mullite and quartz. Mullite was calculated using the molecular formula 2,4Al₂O₃·1,2SiO₂; quartz was calculated using the molecular formula SiO₂. The total mass percentage of SiO₂ in mullite and quartz, and the mass percentage of Al₂O₃ in mullite were calculated.

[0105] ω 晶相SiO2 =10.04%, ω 晶相Al2O3 =0%, ω 晶相MgO =0%, ω 晶相CaO =0%;

[0106] Step 3: The mass percentages of SiO2, Al2O3, MgO, and CaO existing in amorphous phase in the material to be tested are calculated:

[0107] The mass percentage of SiO2 present in amorphous phase in the material under test:

[0108] ω 非晶相SiO2 =ω 总SiO2 -ω 晶相SiO2 =47.57% - 10.04% = 37.53%;

[0109] The mass percentage of Al2O3 existing in the amorphous phase in the tested material:

[0110] ω 非晶相Al2O3 =ω 总Al2O3 -ω 晶相Al2O3 =15.0596% - 0% = 15.0596%;

[0111] The mass percentage of MgO in the amorphous phase in the tested material:

[0112] ω 非晶相MgO =ω 总MgO -ω 晶相MgO =2.49973% - 0% = 2.49973%;

[0113] The mass percentage of CaO present in the amorphous phase in the tested material:

[0114] ω 非晶相CaO =ω 总CaO -ω 晶相CaO =19.0716% - 0% = 19.0716%.

[0115] Step 4: Substitute the mass percentages of SiO2, Al2O3, MgO, and CaO existing in amorphous phases into the activity index calculation formula K = (ω 非晶相CaO +ω 非晶相MgO +ω 非晶相Al2O3 ) / ω 非晶相SiO2 Calculate the activity index of fly ash FA5:

[0116] K FA5 = (19.0716 + 2.49973 + 15.0596) / 37.53 = 0.98.

[0117] Example 6

[0118] This embodiment provides a method for analyzing the reactivity of slag used in geopolymers and applies it to the analysis of slag materials.

[0119] The slag used in this embodiment was purchased from Shijiazhuang Jinming Mining Development Co., Ltd., and is marked as GGBS1.

[0120] The reactivity analysis method in this embodiment includes the following steps:

[0121] Step 1: Perform XRF analysis on the slag material to be tested, and calculate the mass percentage ω of all SiO2, Al2O3, MgO and CaO existing in crystalline and amorphous phases in the material. 总SiO2 =29.5544%, ω 总Al2O3 =11.9931%, ω 总MgO =7.50212%, ω 总CaO =47.1054%;

[0122] Step 2: After adding 15% (by weight) of the internal standard zinc oxide to the test material, XRD analysis was performed. The XRD curves were fitted using TOPAS software to obtain the mass percentages of the amorphous and crystalline phase components in the test material. The crystalline component in the slag was gypsum, calculated using the molecular formula CaSO4·2H2O. The calculated mass percentage of CaO in the gypsum was:

[0123] ω 晶相SiO2 =0%, ω 晶相Al2O3 =0%, ω 晶相MgO =0%, ω 晶相CaO =0.89569%;

[0124] Step 3: The mass percentages of SiO2, Al2O3, MgO, and CaO existing in amorphous phase in the material to be tested are calculated:

[0125] The mass percentage of SiO2 present in amorphous phase in the material under test:

[0126] ω 非晶相SiO2 =ω 总SiO2 -ω 晶相SiO2 =29.5544% - 0% = 29.5544%;

[0127] The mass percentage of Al2O3 existing in the amorphous phase in the tested material:

[0128] ω 非晶相Al2O3 =ω 总Al2O3 -ω 晶相Al2O3 =11.9931% - 0% = 11.9931%;

[0129] The mass percentage of MgO in the amorphous phase in the tested material:

[0130] ω 非晶相MgO =ω 总MgO -ω 晶相MgO =7.50212% - 0% = 7.50212%;

[0131] The mass percentage of CaO present in the amorphous phase in the tested material:

[0132] ω 非晶相CaO =ω 总CaO -ω 晶相CaO =47.1054% - 0.89569% = 46.20971%.

[0133] Step 4: Substitute the mass percentages of SiO2, Al2O3, MgO, and CaO existing in amorphous phases into the activity index calculation formula K = (ω 非晶相CaO +ω 非晶相MgO+ω 非晶相Al2O3 ) / ω 非晶相SiO2 Calculate slag K GGBS1 Activity index:

[0134] K GGBS1 = (46.20971 + 7.50212 + 11.9931) / 29.5544 = 2.22

[0135] Example 7

[0136] This embodiment provides a method for analyzing the reactivity of slag used in geopolymers and applies it to the analysis of slag materials.

[0137] The slag used in this embodiment was purchased from Shijiazhuang Chengtian Building Materials Co., Ltd., and is marked as GGBS2.

[0138] The reactivity analysis method in this embodiment includes the following steps:

[0139] Step 1: Perform XRF analysis on the slag material to be tested, and calculate the mass percentage ω of all SiO2, Al2O3, MgO and CaO existing in crystalline and amorphous phases in the material. 总SiO2 =27.7495%, ω 总Al2O3 =13.9711%, ω 总MgO =6.68152%, ω 总CaO =48.1349%;

[0140] Step 2: After adding 15% (by weight) of the internal standard zinc oxide to the test material, XRD analysis was performed. The XRD curves were fitted using TOPAS software to obtain the mass percentages of the amorphous and crystalline phase components in the test material. The crystalline component in the slag was gypsum, calculated using the molecular formula CaSO4·2H2O. The calculated mass percentage of CaO in the gypsum was:

[0141] ω 晶相SiO2 =0.41%, ω 晶相Al2O3 =0%, ω 晶相MgO =0%, ω 晶相CaO =0%;

[0142] Step 3: The mass percentages of SiO2, Al2O3, MgO, and CaO existing in amorphous phase in the material to be tested are calculated:

[0143] The mass percentage of SiO2 present in amorphous phase in the material under test:

[0144] ω 非晶相SiO2 =ω 总SiO2 -ω 晶相SiO2=27.7495% - 0.41% = 27.3395%;

[0145] The mass percentage of Al2O3 existing in the amorphous phase in the tested material:

[0146] ω 非晶相Al2O3 =ω 总Al2O3 -ω 晶相Al2O3 =13.9711% - 0% = 13.9711%;

[0147] The mass percentage of MgO in the amorphous phase in the tested material:

[0148] ω 非晶相MgO =ω 总MgO -ω 晶相MgO =6.68152% - 0% = 6.68152%;

[0149] The mass percentage of CaO present in the amorphous phase in the tested material:

[0150] ω 非晶相CaO =ω 总CaO -ω 晶相CaO =48.1349% - 0% = 48.1349%.

[0151] Step 4: Substitute the mass percentages of SiO2, Al2O3, MgO, and CaO existing in amorphous phases into the activity index calculation formula K = (ω 非晶相CaO +ω 非晶相MgO +ω 非晶相Al2O3 ) / ω 非晶相SiO2 Calculate slag K GGBS2 Activity index:

[0152] K GGBS2 = (48.1349 + 6.68152 + 13.9711) / 27.3395 = 2.52.

[0153] Example 8

[0154] This embodiment provides a method for analyzing the reactivity of slag used in geopolymers and applies it to the analysis of slag materials.

[0155] The slag used in this embodiment was purchased from Lingshou County Boheng Mineral Products Trading Co., Ltd., and was marked as GGBS3.

[0156] Step 1: Perform XRF analysis on the slag material to be tested, and calculate the mass percentage ω of all SiO2, Al2O3, MgO and CaO existing in crystalline and amorphous phases in the material. 总SiO2 =30.2061%, ω 总Al2O3 =13.4561%, ω 总MgO=6.60313%, ω 总CaO =47.3969%;

[0157] Step 2: After adding 15% (by weight) of the internal standard zinc oxide to the test material, XRD analysis was performed. The XRD curves were fitted using TOPAS software to obtain the mass percentages of the amorphous and crystalline phase components in the test material. The crystalline component in the slag was gypsum, calculated using the molecular formula CaSO4·2H2O. The calculated mass percentage of CaO in the gypsum was:

[0158] ω 晶相SiO2 =0%, ω 晶相Al2O3 =0%, ω 晶相MgO =0%, ω 晶相CaO =0%;

[0159] Step 3: The mass percentages of SiO2, Al2O3, MgO, and CaO existing in amorphous phase in the material to be tested are calculated:

[0160] The mass percentage of SiO2 present in amorphous phase in the material under test:

[0161] ω 非晶相SiO2 =ω 总SiO2 -ω 晶相SiO2 =30.2061% - 0% = 30.2061%;

[0162] The mass percentage of Al2O3 existing in the amorphous phase in the tested material:

[0163] ω 非晶相Al2O3 =ω 总Al2O3 -ω 晶相Al2O3 =13.4561% - 0% = 13.4561%;

[0164] The mass percentage of MgO in the amorphous phase in the tested material:

[0165] ω 非晶相MgO =ω 总MgO -ω 晶相MgO =6.60313% - 0% = 6.60313%;

[0166] The mass percentage of CaO present in the amorphous phase in the tested material:

[0167] ω 非晶相CaO =ω 总CaO -ω 晶相CaO =47.3969% - 0% = 47.3969%.

[0168] Step 4: Substitute the mass percentages of SiO2, Al2O3, MgO, and CaO existing in amorphous phases into the activity index calculation formula K = (ω 非晶相CaO +ω 非晶相MgO +ω 非晶相Al2O3 ) / ω 非晶相SiO2 Calculate slag K GGBS3 Activity index:

[0169] K GGBS3 = (47.3969 + 6.60313 + 13.4561) / 30.2061 = 2.23.

[0170] The accuracy of the reactivity analysis method of the present invention was verified by measuring the compressive strength of the slurry test blocks prepared from fly ash or slag at different curing ages as analyzed in Examples 1-8.

[0171] Mechanical property testing methods:

[0172] All experiments used NaOH granules to prepare 3M NaOH solutions. The study found that 3M NaOH solution provides [OH-]. - The concentration was sufficient to completely dissolve the amorphous phase in fly ash and slag. Preliminary experiments showed that a constant water-cement ratio (w / b) of 0.43 was the minimum water-cement ratio within the normal flowability range for all eight materials in Examples 1-8. The required slurry mixing ratio was 100 grams of raw material and 48.5 grams of NaOH solution (3M).

[0173] To prepare the alkali-activated adhesive, the solid materials were first mixed for 3 minutes, then the alkali solution was gradually added and stirred for another 3 minutes. After mixing, the fresh slurry was poured into a mold with dimensions of 50mm × 50mm × 50mm and vibrated on a vibration table for 2 minutes. Subsequently, the sample was stored in an environment of 20℃ ± 1℃ and relative humidity greater than 95% until the 7 / 28-day strength test was conducted. The test results and the corresponding activity index K are shown in Table 1.

[0174] Table 1

[0175]

[0176] Linear fitting was performed on the strength of all materials from Examples 1-8 after alkali activation for 28 days and the activity index calculated from the amorphous phase content. The results are as follows: Figure 1 As shown, the obtained fitting variance R 2 =0.97, thus proving the correctness of the results obtained by the reaction activity analysis method of the present invention.

Claims

1. A method for analyzing the reactivity of fly ash / slag in geopolymers, characterized in that, The steps include the following: Step 1: Perform XRF analysis on the fly ash or slag material to be tested, and calculate the mass percentage ω of all SiO2, Al2O3, MgO and CaO existing in crystalline and amorphous phases in the material to be tested. 总SiO2 ω 总Al2O3 ω 总MgO , ω 总CaO ; Step 2: After adding an internal standard to the test material, perform XRD analysis, fit the XRD curve, and calculate the mass percentage ω of SiO2, Al2O3, MgO, and CaO existing in crystalline form in the test material. 晶相SiO2 ω 晶相Al2O3 ω 晶相MgO ω 晶相CaO ; Step 3: Calculate the mass percentage ω of SiO2, Al2O3, MgO, and CaO existing in amorphous phase in the material to be tested. 非晶相SiO2 ω 非晶相Al2O3 ω 非晶相MgO ω 非晶相CaO ; Step 4: Calculate the activity index using the formula K = (ω...) 非晶相CaO +ω 非晶相MgO +ω 非晶相Al2O3 ) / ω 非晶相SiO2 Calculate the activity index of the material to be tested. The higher the activity index, the better the reactivity.

2. The method for analyzing the reactivity of fly ash / slag for geopolymers according to claim 1, characterized in that, The internal standard mentioned in step two is zinc oxide, and the amount of zinc oxide added is 15% of the weight of the material to be tested.

3. The method for analyzing the reactivity of fly ash / slag for geopolymers according to claim 1 or 2, characterized in that, Step two involves fitting the XRD curve using TOPAS software.

4. The method for analyzing the reactivity of fly ash / slag for geopolymers according to claim 3, characterized in that, Step 2, XRD analysis, revealed that the substances present in the fly ash sample in crystalline form were mullite and quartz.

5. The method for analyzing the reactivity of fly ash / slag for geopolymers according to claim 4, characterized in that, The mullite was calculated according to the molecular formula 2,4Al2O3·1,2SiO2; the quartz was calculated according to the molecular formula SiO2. The total mass percentage of SiO2 in mullite and quartz and the mass percentage of Al2O3 in mullite were calculated respectively.

6. The method for analyzing the reactivity of fly ash / slag for geopolymers according to claim 5, characterized in that, Step two, XRD analysis, revealed that the substance in the slag existing in crystalline form was gypsum.

7. The method for analyzing the reactivity of fly ash / slag for geopolymers according to claim 6, characterized in that, The gypsum is calculated according to the molecular formula CaSO4·2H2O; the mass percentage of CaO in the gypsum is obtained by calculation.

8. The method for analyzing the reactivity of fly ash / slag for geopolymers according to claim 7, characterized in that, In step three, ω 非晶相SiO2 ω 非晶相Al2O3 ω 非晶相MgO ω 非晶相CaO The calculation formula is: oh 非晶相SiO2 =ω 总SiO2 -oh 晶相SiO2 ; oh 非晶相Al2O3 =ω 总Al2O3 -oh 晶相Al2O3 ; oh 非晶相MgO =ω 总MgO -oh 晶相MgO ; oh 非晶相CaO =ω 总CaO -oh 晶相CaO 。

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