Calcium ferroaluminate compound, cement admixture and process for producing same, and cement composition

A technology of calcium ferric aluminate and compound, applied in the direction of iron compound, chemical instrument and method, preparation of alkaline earth metal aluminate/alumina/aluminum hydroxide, etc., can solve the problem of not confirming the effect of nitrite acid resistance and the like , to achieve excellent anti-rust effect, sufficient operating time, and the effect of infiltration inhibition

Active Publication Date: 2013-01-09
DENKA CO LTD
View PDF7 Cites 12 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the effect of nitrite imparting acid resistance was not confirmed

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Calcium ferroaluminate compound, cement admixture and process for producing same, and cement composition
  • Calcium ferroaluminate compound, cement admixture and process for producing same, and cement composition
  • Calcium ferroaluminate compound, cement admixture and process for producing same, and cement composition

Examples

Experimental program
Comparison scheme
Effect test

Embodiment

[0063] (specification of the crystal structure of the compound)

[0064] Synthetic calcium ferrite (C 2 F), calcium aluminum ferrite (C 4 AF, C 6 A 2 F, C 6 AF 2 ), calcium aluminate, calcium aluminate (CA 2 ).

[0065] figure 1 Show calcium ferrite (C 2 F) and calcium aluminum ferrite (C 4 AF, C 6 A 2 F, C 6 AF 2 ) XRD measurement result. Depend on figure 1 It can be seen that these have the same crystal structure.

[0066] on the other hand, figure 2 Calcium aluminate and calcium aluminate (CA 2 ) XRD measurement result. It can be seen that calcium aluminum ferrite maintains CA 2 While the structure, Fe 2 o 3 solid solution. In addition, if Fe 2 o 3 If it exceeds 15%, there will be no solid solution, and the precipitation of magnetite can be seen. It has been confirmed from the above that calcium aluminate ferrite is different from the previously known CaO-Al 2 o3 -Fe 2 o 3 The calcium aluminum ferrite system compound is a completely different co...

experiment example 1

[0068] Calcium carbonate of reagent grade 1 and aluminum oxide of reagent grade 1 were compounded so that the molar ratios shown in Table 1 were obtained in terms of oxides, and iron oxide of reagent grade 1 was adjusted to the ratio shown in Table 1 with respect to the complex. Fe 2 o 3 The method of content is compounded and fired in an electric furnace. CaO / Al 2 o 3 The substance with a molar ratio of 0.7 is at 1400°C, CaO / Al 2 o 3 The substance with a molar ratio of 0.6 is at 1450°C, CaO / Al 2 o 3 The substance with a molar ratio of 0.4 is at 1500°C, CaO / Al 2 o 3 The substances with a molar ratio of 0.15 were respectively calcined at 1550° C. for 3 hours, and then slowly cooled to synthesize them. All Blaine values ​​adjusted to 4,000cm 2 / g. In addition, for comparison, for the case of not adding iron oxide, containing SiO 2 case, containing R 2 The case of O is also synthesized in the same manner. The presence or absence of unreacted substances was evaluated...

experiment example 2

[0078] Cement compositions were prepared by mixing 7 parts of the CFA compounds shown in Table 2 with 100 parts of cement compositions consisting of cement and CFA compounds, and mortars with a water / binder ratio of 0.5 were prepared in accordance with JIS R 5201. Using this mortar, setting time, antirust effect, compressive strength, chloride penetration depth, Ca ion infiltration, and sulfate resistance were investigated. The results are also listed in Table 1. In addition, the test was performed at an ambient temperature of 30°C.

[0079]

[0080] CFA compound A: mix the calcium carbonate of the reagent grade 1 with the alumina of the reagent grade 1 in a specified ratio, and use Fe 2 o 3 The iron oxide of grade 1 of the reagent is mixed so that the content becomes 3%, and it is synthesized by firing in an electric furnace at 1550°C in the same manner as in Experimental Example 1, and then slowly cooling CaO / Al 2 o 3 Molar ratio 0.1, Blaine value 4,000cm 2 / g

[008...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
specific surface areaaaaaaaaaaa
Login to view more

Abstract

Provided is a cement admixture which gives cured cement concrete that imparts excellent non-corrodible properties to the reinforcing bars present therein, has resistance to external infiltration of chloride ions, and can be inhibited from becoming porous because Ca-ion eluviation occurs little and that has self-healing ability. Also provided is a cement composition. The cement admixture is characterized by comprising a calcium ferroaluminate compound which is based on CaO, Al2O3, and Fe2O3, has a Fe2O3 content of 0.5-15 mass%, and has a CaO2Al2O3 structure, the CaO/Al2O3 ratio being in the range of 0.15-0.7 by mole. It is preferred that the admixture have a degree of fineness of 2,000-7,000 cm2/g in terms of Blaine specific surface area and that a latent hydraulic substance and/or a pozzolanic substance (pozzolanic substance and the like) be used in combination with the calcium ferroaluminate compound. The pozzolanic substance and the like preferably comprise one or more substances selected from a group consisting of ground granulated blast furnace slag, fly ash, silica fume, metakaolin, incineration ash of pulp sludge, incineration ash of sewage sludge, and waste glass powder. It is preferred that the ratio of the calcium ferroaluminate compound to the pozzolanic substance and the like be from 10/1 to 1/10 by mass. The cement composition comprises cement and the cement admixture.

Description

technical field [0001] The present invention mainly relates to cement admixtures and cement compositions used in civil engineering and construction industries. Background technique [0002] CaO-Al used as cement admixture 2 o 3 -Fe 2 o 3 The compound of the system is known as calcium aluminum ferrite. Calcium aluminum ferrite known as 4CaO·Al 2 o 3 · Fe 2 o 3 (C 4 AF), 6CaO 2Al 2 o 3 · Fe 2 o 3 (C 6 A 2 F), 6CaO·Al 2 o 3 2Fe 2 o 3 (C 6 AF 2 )Wait. [0003] These aluminum calcium ferrites have 2CaO·Fe as one of the calcium ferrites 2 o 3 (C 2 F) Crystal structure. Namely, Al 2 o 3 Much solid solution in C 2 While F, the crystal structure remains C 2 The structure of F, to obtain Al with various compositions 2 o 3 / Fe 2 o 3 The molar ratio of. C 2 The crystal structure of F is orthorhombic, [0004] On the other hand, CaO·2Al is known as one type of calcium aluminate 2 o 3 (CA 2 ). CA 2 The crystal structure is monoclinic, ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C04B22/08C01G49/00
CPCC04B22/0093C04B7/32C01P2002/72C04B2111/26C01G49/0036C01G49/0045C01F7/16C04B28/02Y02W30/91C04B2103/0088C04B14/106C04B14/22C04B18/08C04B18/10C04B18/141C04B18/146
Inventor 森泰一郎田原和人山本贤司盛冈实樋口隆行
Owner DENKA CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap