Method for removing and recycling hexavalent chromium ions by using chitosan-iron complex

A technology of hexavalent chromium ions and iron complexes, applied in chemical instruments and methods, water pollutants, water/sewage treatment, etc., can solve the problems of cumbersome preparation, new material removal efficiency needs to be improved, and inconvenient operation. Simplicity, improved adsorption performance, and low cost

Inactive Publication Date: 2011-02-16
ZHEJIANG UNIV
View PDF3 Cites 22 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the removal efficiency of these new materials needs to be improved,

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 removing and recycling hexavalent chromium ions by using chitosan-iron complex
  • Method for removing and recycling hexavalent chromium ions by using chitosan-iron complex
  • Method for removing and recycling hexavalent chromium ions by using chitosan-iron complex

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0030] Prepare 0.05mol / L FeCl 3 Solution 50mL (0.0025mol), slowly add chitosan monomer 2.67g (molecular weight is 1,000,000, deacetylation degree is 91%), make chitosan monomer and Fe 3+ The molar ratio of the chitosan-iron complex is 6:1, keep stirring for 2 hours to make the two fully react, then slowly add 50mL of ethanol and stir slowly at the same time, after the chitosan-iron complex precipitation is gradually formed, centrifuge and wash with absolute ethanol to unreacted Fe 3+ , then add 25% glutaraldehyde 5mL, cross-linking reaction for 2h, and finally use absolute ethanol to wash glutaraldehyde again, centrifuge, dry at 80°C, grind finely, and prepare reduction-adsorption bifunctional chitosan-iron Complexes.

Embodiment 2

[0032] Prepare 0.1mol / L FeCl 3 Solution 50mL (0.005mol), slowly add chitosan monomer 2.67g (molecular weight is 1,000,000, deacetylation degree is 91%), make chitosan monomer and Fe 3+ The molar ratio of the chitosan-iron complex is 3:1, keep stirring for 2 hours to make the two fully react, then slowly add 50mL of ethanol and stir slowly at the same time, after the chitosan-iron complex precipitation is gradually formed, centrifuge and wash with absolute ethanol to unreacted Fe 3+ , then add 25% glutaraldehyde 5mL, cross-linking reaction for 2h, finally use absolute ethanol to wash the glutaraldehyde again, centrifuge, dry at 80°C, and grind finely to obtain the reduction-adsorption bifunctional chitosan-iron complex Thing, structure is as shown in formula (I):

[0033]

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 for removing and recycling hexavalent chromium ions by using a chitosan-iron complex. The method comprises the following steps: adding the chitosan-iron complex in which the molar ratio of the chitosan to the iron ions is 3 to 6:1 into an aqueous solution containing 10 to 200 mg/L hexavalent chromium ions and having a pH value of 3 to 10; stirring the mixture, centrifuging and filtering; drying the filter cake to obtain the chitosan-iron complex adsorbing the hexavalent chromium ions, wherein the iron ions are ferric ions; adding the chitosan-iron complex adsorbing the hexavalent chromium ions into an alkaline aqueous solution; and stirring the mixture and filtering, wherein the obtained filtrate is the solution of the recycled hexavalent chromium ions, and the alkaline aqueous solution is the aqueous solution of NaOH, Na2CO3 or NaHCO3. The method for removing and recycling the hexavalent chromium ions by using the chitosan-iron complex has the advantages of simple implementation, environmental protection and low cost.

Description

technical field [0001] The invention relates to the field of post-treatment of heavy metal ions in waste water, in particular to a method for removing and recovering heavy metal hexavalent chromium ions in waste water by using a chitosan-iron complex with dual functions of reduction and adsorption. Background technique [0002] Chromium (Cr) is one of the common toxic heavy metal elements, which mainly exist in two valence states of trivalent chromium (Cr(III)) and hexavalent chromium (Cr(VI)) in the environment. Among them, Cr(VI) is widely used in tanning, textile production, printing and dyeing, pigments, and electroplating industries. It is highly toxic, difficult to be biodegraded, and difficult to handle. It is a ubiquitous pollutant. Especially in the electroplating industry, only 10% of the chromium is plated on the plated parts in the chrome plating process, and 30-73% of the chromium is discharged along with the production wastewater, and the pollution to the envir...

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): C02F1/62C02F101/22
Inventor 文岳中沈忱思刘维屏
Owner ZHEJIANG 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