Nm-class calcium carbonate carbonization process

A technology of nano-calcium carbonate and process method, which is applied in the field of nano-powder preparation, can solve the problems of large investment in equipment, no discovery of nano-calcium carbonate, poor control of inclusion particles, etc., and achieve the effect of shortening the reaction time

Active Publication Date: 2007-05-16
TSINGHUA UNIV
View PDF28 Cites 24 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The method has high efficiency in producing nano-calcium carbonate, good economic benefits, and can realize automatic large-scale production. The particle size is easy to control, and high-quality and stable nano-calcium carbonate can be produced. The disadvantage is that the equipment investment is large, and it is easy to control if it is not good. Incompletely carbonized inclusion particles
Including: "Method for preparing nano calcium carbonate particle" (CN1631789-A), "Method for preparing nano precipitated calcium carbonate from industrial waste water by sodium bicarbonate process" (CN1699176-A), "Process for preparing high activitycateactive nano CN1491893-A), "Preparation method of n

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
  • Nm-class calcium carbonate carbonization process
  • Nm-class calcium carbonate carbonization process

Examples

Experimental program
Comparison scheme
Effect test

Example Embodiment

[0042] Example 1:

[0043] The lime was digested with hot water at 85°C, aged for 8 hours, and the ratio of grey to water was 1:4. The concentration of carbon dioxide in the mixed gas is 30%; the density of calcium hydroxide suspension is 1.055g / cm 3 , the concentration is 9.6%, and the sedimentation volume is 3.35ml / g. The additive citric acid is chemically pure, and the weight percentage of citric acid added before carbonization is 0.42%. Using a new carbonization process with circulation and strong shear mixing, the reaction time of the entire carbonization process lasted 31 minutes, the initial temperature was 18 °C, and the reaction end point was 33.5 °C; when the pH value of the suspension dropped to 7, the reaction was stopped, and the slurry settled. The volume is 5.84ml / g, filtered and dried. The particle size of the nano-calcium carbonate product is between 60-85nm, the crystal morphology is a regular cubic structure, and the specific surface area of ​​the nano-cal...

Example Embodiment

[0044] Example 2:

[0045] The lime was digested with hot water at 85°C, aged for 15 hours, and the ratio of grey to water was 1:4. The carbon dioxide concentration in the mixed gas is 30%; the density of the calcium hydroxide suspension is 1.055g / cm3, the concentration is 9.6%, and the sedimentation volume is 3.35ml / g. The additive citric acid is chemically pure, and the weight percentage of citric acid added before carbonization is 1.68%. Adopting a new carbonization process with circulation and strong shear mixing, the reaction time of the entire carbonization process lasted 32 minutes, the initial temperature was 18 °C, and the reaction end temperature was 34 °C; when the pH value of the suspension dropped to 7, the reaction was stopped, and the slurry The sedimentation volume is 3.54ml / g, filtered and dried, the particle size of the nano calcium carbonate product is between (50-60)×330nm, the crystal morphology is a chain structure, and the specific surface area of ​​the...

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
Granularityaaaaaaaaaa
Specific surface areaaaaaaaaaaa
Granularityaaaaaaaaaa
Login to view more

Abstract

The invention discloses a carbonizing technological method of nanometer calcium carbonate in the nanometer powder making technological domain, which comprises the following steps: allocating calcium hydroxide solution with density at 8-12%(m) and density at 1.04-1.07g/cm3; setting the starting temperature at 15-20Deg C; pouring into intermittent stirring reacting autoclave; stirring completely; circulating the slurry; introducing composite gas of carbon dioxide into circulating pipe and strong cutting blender to blend with circulating suspension liquid; entering into buffer tank or autoclave through circulating pipe; stopping reacting until the pH value of suspension liquid is 7-7.5; maintaining 30-70min for entire carbonizing course; setting the terminal temperature within 30-40Deg C.

Description

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

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
Owner TSINGHUA UNIV
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.

© 2023 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap