Method for treating Cr6+ in waste water and method for preparing montmorillonite-base nano magnetite used thereof

A montmorillonite-based, nano-magnet technology, applied in water/sewage treatment, adsorption water/sewage treatment, water/sludge/sewage treatment, etc., can solve problems such as secondary pollution and inability to restore hexavalent chromium, and achieve The effect of easy recovery, strong adsorption, and large specific surface area

Inactive Publication Date: 2008-07-09
GUANGZHOU INST OF GEOCHEMISTRY - CHINESE ACAD OF SCI
View PDF4 Cites 20 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to overcome the deficiency that the prior art cannot reduce hexavalent chromium to trivalent chromium with low toxicity, and the adsorbed hexavalent chromium may s

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
  • Method for treating Cr6+ in waste water and method for preparing montmorillonite-base nano magnetite used thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0021] Example 1: Preparation of montmorillonite-based nano-magnetite adsorption material

[0022] 1) Weigh 170g FeCl 3 ·6H 2 O with 122gFeCl 2 4H 2 O, placed in a reactor filled with 5L of distilled water, stirred to dissolve.

[0023] 2) Heat the suspension to 60°C and keep it warm; under continuous stirring conditions, slowly add ammonia solution with a concentration of 10% (mass percentage) into the suspension, and stop dripping when the pH value of the suspension reaches 9. Add, continue to keep warm, stir for 2 hours.

[0024] 3) Centrifuging the suspension, and centrifuging and rinsing the magnetite wet precipitate with distilled water for 6 times, so that the pH value of the centrifuged supernatant is neutral. Then, 3 L of 0.01 mol / L hydrochloric acid was added to the obtained magnetite wet precipitate, fully stirred to disperse it evenly, and then the precipitate was centrifuged.

[0025] 4) Add 2 L of distilled water to the separated precipitate and stir thorou...

Embodiment 2

[0030] Potassium dichromate (K 2 Cr 2 o 7 ) for Cr 6+ source, formulated Cr 6+300ml of simulated wastewater with a concentration of 200mg / L and a pH value of 3.0. Weigh 36.6 g of the montmorillonite-based nano-magnetite adsorption material prepared in Example 1, add it to the prepared wastewater, stir for 5 minutes, and let stand for 15 minutes. Then use a common circular magnet with a diameter of 16cm to absorb the precipitate to achieve solid-liquid separation. After testing, the pH of the treated water is neutral, where Cr 6+ The concentration is lower than 0.01mg / L, which meets the discharge standard.

Embodiment 3

[0032] Potassium dichromate (K 2 Cr 2 o 7 ) for Cr 6+ source, formulated Cr 6+ 600ml of simulated wastewater with a concentration of 100mg / L and a pH value of 6.0. Weigh 68.2 g of the montmorillonite-based nano-magnetite adsorption material prepared in Example 1, add it into the prepared wastewater, stir for 5 minutes, and let stand for 15 minutes. Then use a common circular magnet with a diameter of 16cm to absorb the precipitate to achieve solid-liquid separation. After testing, the pH of the treated water is neutral, where Cr 6+ The concentration is lower than 0.01mg / L, which meets the discharge standard.

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
Particle sizeaaaaaaaaaa
Diameteraaaaaaaaaa
Login to view more

Abstract

Provided is a process for treating Cr6+ in waste water, which comprises: adding nano magnetite of montmorillonite substrate in waste water containing hexavalent chromium, stirring for 5 minutes to 2 hours at normal temperature and then placing for 15 minutes to 2 hours, employing magnet or additional magnetic field to recycle adsorption materials. The process for preparation by employing the nano magnetite of montmorillonite substrate comprises that mixing ferric salt and ferrous iron salt solution, adding by ammonia spirit, adding by hydrochloric acid after filtering, rinsing and solid-liquid separation treatment, adding by montmorillonite then solid-liquid separating, drying and dewatering and the like. The invention of treating waste water containing Cr6+ has the advantages of high efficiency, low cost, simple operation and the like, and can be widely used for waste water treatment in a plurality of fields, such as tanning, plating, metallurgy, pharmacy, ferrochrome smelting, pigment, chromic salt chemical industry and the like.

Description

technical field [0001] The invention relates to a kind of Cr in waste water 6+ The processing method and the preparation method of the montmorillonite-based nano-magnetite adsorption material used. Background technique [0002] Hexavalent chromium (Cr 6+ , or Cr(VI)) is a highly toxic heavy metal pollutant. It is mainly produced in the industrial wastewater discharged from industries such as tanning, metallurgy and electroplating. Because hexavalent chromium is extremely harmful to environmental safety and human health, my country has listed hexavalent chromium as the first category of pollutants in the comprehensive sewage discharge standard (GB8978-1996), and stipulated that its emission concentration must be lower than 0.5mg / L . Treatment of Cr in Industrial Wastewater 6+ It has been highly valued by relevant departments, scientific research institutions and business circles. Common treatments contain Cr 6+ Wastewater methods mainly include chemical reduction method...

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
IPC IPC(8): C02F1/64C02F1/28B01J20/30
Inventor 袁鹏何宏平樊明德杨丹朱建喜颜文昌
Owner GUANGZHOU INST OF GEOCHEMISTRY - CHINESE ACAD OF SCI
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