Method for strengthening azo dye biodegradation by utilizing zero-valent iron

An azo dye, biodegradation technology, applied in chemical instruments and methods, water pollutants, water/sludge/sewage treatment, etc., can solve the problems of microbial reaction rate limitation, inability to achieve complete mineralization of azo dyes, etc. Achieve the effect of rapid COD removal, rapid degradation, and promotion of recovery

Active Publication Date: 2015-06-24
GUANGDONG INST OF MICROBIOLOGY GUANGDONG DETECTION CENT OF MICROBIOLOGY
View PDF2 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The reduction of zero-valent iron (ZVI) can promote the reductive degradation of azo dyes, but the complete mineralization of azo dyes cannot be achieved
At the same time, the iron-reducing bacteria existing in the environment can utilize Fe under anaerobic conditions. 3+ As an electron acceptor, it realizes the transformation of azo dyes, but the microbial reaction rate is limited by conditions such as oxygen environment and dye toxicity

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 strengthening azo dye biodegradation by utilizing zero-valent iron
  • Method for strengthening azo dye biodegradation by utilizing zero-valent iron
  • Method for strengthening azo dye biodegradation by utilizing zero-valent iron

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0015] Example 1: Effect of adding zero-valent iron on the removal of amaranth in reactor

[0016] Artificially prepared azo dye wastewater was used as reaction influent. With sucrose-C, (NH4) 2 SO 4 -N, KH 2 PO 4 -P is used as carbon source, nitrogen source and phosphorus source, its COD:N:P ratio is 200:5:1, the initial influent COD is 500mg / L; the trace element is CoCl 2 .6H 2 O:0.5g·L -1 , NiCl.6H 2 O:0.05g·L -1 、CuSO 4 .5H 2 O:0.0465g·L -1 , ZnSO 4 :0.0893g·L -1 、H 3 BO 3 :0.05g·L -1 , MnCl 2 .4H 2 O:0.5g·L -1 , (NH 4 ) 6 Mo 7 o 24 .2H 2 O:0.01g·L -1 ; Amaranth concentration from 0.025mmol L -1 Gradually increase to 0.4mmol·L -1 , pH8.0, the balance is water. See the run time for each amaranth concentration gradient figure 2 . The anoxic-aerobic-anoxic sequencing batch reactor process is adopted, and the process parameters are: hydraulic retention time is 48h: anaerobic section 24h, aerobic section 12h, anaerobic section 10h, idle 2h, and the...

Embodiment 2

[0017] Example 2: The effect of adding zero-valent iron on the pH of the effluent under the condition of high COD load in the reactor

[0018] Artificial water distribution formula, reactor design (reactor R1 is only inoculated with activated sludge, and reactor R2 is inoculated with activated sludge based on adding zero-valent iron, and the dosage is 6mmol L -1 ), the operating parameters were the same as those in Example 1, when running for 38 days, the COD of the influent was adjusted from 500mg / L to 1000mg / L, and the pH changes of the effluent of the reactor with added parts iron and zero-valent iron were compared. The result is as image 3 As shown, when the COD is 500mg / L, the pH of the effluent from reactors R1 and R2 is about 7.0, and the COD removal rate is 85%. When the COD rises to 1000mg / L, the effluent from the reactor is acidic, the pH of the effluent from the reactor R1 is 3.3-5.0, and the pH of the effluent from the reactor R2 is 5.4-6.8. At the same time, th...

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 strengthening azo dye biodegradation by utilizing zero-valent iron. The method comprises the following steps of: adding zero-valent iron into an active-sludge containing reactor for treating the azo dye wastewater; and realizing the azo dye biodegradation by adopting an anoxic-aerobiotic-anoxic sequencing type reactor process. According to the method, the anoxic-aerobiotic-anoxic sequencing type reactor process is adopted, and azo-containing wastewater and zero-valent iron are added, so that on one hand, zero-valent iron is used for chemical reduction of the azo dye at a first anoxic stage, on the other hand, zero-valent iron is used as an electron donor for promoting the microorganism growth, and therefore, the azo dye is catalyzed for being reduced and degraded into an aromatic compound; at an aerobiotic stage, the aerobiotic microorganisms are used for oxidizing and mineralizing the aromatic compound; meanwhile, the generated Fe<2+> is oxidized into Fe<3+>; at a second anoxic stage, generated Fe<3+> is used as an electron mediator or an electron receptor, so that the reduction activity of the microorganisms is promoted to be recovered, and COD (Chemical Oxygen Demand) is further removed, and therefore, preparation is made for taking in the fresh azo dye wastewater.

Description

technical field [0001] The invention belongs to the field of biotechnology, and in particular relates to a method for using zero-valent iron to strengthen the biodegradation of azo dyes. Background technique: [0002] With the development of the modern chemical industry, dyes are widely used in the dyeing and printing processes of various industries. The annual discharge of printing and dyeing wastewater in the world is about 280,000 tons. Among them, azo dyes are used in the largest amount, and about 70% of synthetic dyes are made on the basis of azo chemistry. There are more than 3,000 kinds of azo dyes currently in use, almost all of which are synthetic products, which have high chemical stability and are difficult to biodegrade, and most azo dyes and their metabolic intermediates are strongly mutagenic and carcinogenic , teratogenicity and other toxicity, direct discharge into the water body will pose a threat to the ecological environment and cause harm to human health...

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): C02F3/30C02F101/38
Inventor 许玫英周庆方云陈杏娟孙国萍
Owner GUANGDONG INST OF MICROBIOLOGY GUANGDONG DETECTION CENT OF MICROBIOLOGY
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