Method used for reinforced electric restoration of arsenic chromium composite polluted soil with reducing agent/chelating agent

A combined pollution and electric repair technology, applied in the field of soil remediation, can solve the problems of reducing the remediation rate and prolonging the remediation period, and achieves the effects of convenient operation, efficient removal and low cost

Inactive Publication Date: 2019-05-03
SHANGHAI UNIV
View PDF9 Cites 8 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, in this method, microorganisms—Acidothiobacillus thiooxidans are added to realize the activation and dissolution of metal ions in the soil. It takes 7 days to activate the heavy metals after the bacteria are added, which reduces the repair rate and prolongs the repair cycle.

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 used for reinforced electric restoration of arsenic chromium composite polluted soil with reducing agent/chelating agent
  • Method used for reinforced electric restoration of arsenic chromium composite polluted soil with reducing agent/chelating agent
  • Method used for reinforced electric restoration of arsenic chromium composite polluted soil with reducing agent/chelating agent

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0020] A reducing agent / chelating agent strengthens the method for electrically repairing arsenic-chromium composite polluted soil, and its specific steps are as follows:

[0021] a. Air-dry 600g of arsenic-chromium composite polluted soil, crush it, remove gravel and plant residue, and pass through a 20-mesh sieve to obtain arsenic-chromium composite polluted soil powder, which is stored for later use;

[0022] b. 5.55g (50mmol) calcium chloride (CaCl 2 ) and 6.04g (25mmol) aluminum chloride hexahydrate (AlCl 3 ·6H 2 O) Stir evenly to obtain a mixed solution; under the condition of filling nitrogen, slowly pour 50ml of sodium hydroxide (NaOH) solution into the above mixed solution while stirring, stir for 60min, and prepare a layered double hydroxide (CaCl 2 and AlCl 3 ·6H 2 (0) solution; then stirred at room temperature for 23 hours, then suction filtered, placed in a 105°C oven for drying, took out the solid sample, and then washed repeatedly with distilled water under ...

Embodiment 2

[0026] The method for remediating arsenic-chromium composite polluted soil in Example 2 is the same as Example 1, except that the reducing agent in step c in Example 2 is 0.05M citric acid combined with 0.05M EDTA-2Na. After the reaction, the average removal rates of arsenic and chromium in the repaired soil were determined to be 41.2% and 46.8%, respectively. from figure 2 (b) and image 3 (b) It can be seen that in the six sampling points from S1 to S6, the proportion of residual arsenic and chromium in the soil to the total amount of original arsenic and chromium (C / C 0 ) are less than 1, indicating that the arsenic-chromium composite polluted soil has been restored.

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

No PUM Login to view more

Abstract

The invention discloses a method used for reinforced electric restoration of arsenic chromium composite polluted soil with a reducing agent/a chelating agent. The method comprises following steps: a,arsenic chromium composite polluted soil is subjected to air drying and crushing so as to obtain arsenic chromium composite polluted soil powder; b, calcium chloride and aluminium chloride hexahydrateare stirred to be uniform so as to obtain a mixed solution; with nitrogen gas introduction and stirring, a sodium hydroxide solution is added into the mixed solution so as to obtain a layered doublehydroxide solution; with nitrogen gas introduction, washing, drying, and grinding are carried out so as to obtain a layered double hydroxide powder; and c, the arsenic chromium composite polluted soilpowder and the layered double hydroxide powder are introduced into the space between two permeable reactive barriers of an electrokinetic remediation-permeable reactive barrier (EK-PRB) restoration device, reducing agents or composite reagents such as ascorbic acid and sodium citrate are added into the polluted soil, an obtained product is allowed to stand, and is provided with electricity for restoration. The method is capable of removing arsenic and chromium in soil with high efficiency; operation is convenient; cost is low; period is short; and the layered double hydroxide CaAl-LDH is recoverable.

Description

technical field [0001] The invention relates to a method for repairing arsenic-chromium compound polluted soil by a reducing agent / chelating agent enhanced electrokinetic-permeable reaction wall (EK-PRB), and belongs to the technical field of soil restoration. Background technique [0002] In recent years, the situation of soil pollution in my country has become increasingly severe. The "National Soil Pollution Survey Bulletin" released in 2014 pointed out that heavy metal pollution is very serious. Among them, the over-standard rate of arsenic pollution points was 2.7%, and the over-standard rate of chromium pollution points was 1.1%. The combined pollution of arsenic and chromium in soil is mainly caused by the massive use of preservatives containing arsenic and chromium in the wood preservation industry. The commonly used reagents for wood preservation and prolonging the service life of wood are mainly inorganic preservatives such as copper chromium arsenic (CCA-C). The...

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): B09C1/08B09C1/00C01F11/02
Inventor 许云峰张亮刘秋龙王昕夏薇钱光人
Owner SHANGHAI 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.

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