CN109777839A

CN109777839A - A kind of citrobacter freundii goes cadmium and the method for generating nano material in water removal

Info

Publication number: CN109777839A
Application number: CN201711104973.XA
Authority: CN
Inventors: 王珅; 郭思瑶; 韩松; 刘力宁; 于杰
Original assignee: Northeast Forestry University
Current assignee: Northeast Forestry University
Priority date: 2017-11-10
Filing date: 2017-11-10
Publication date: 2019-05-21
Anticipated expiration: 2037-11-10
Also published as: CN109777839B

Abstract

It the present invention relates to the use of microculture, water body purification, nano material synthesis technical field, pass through culture citrobacter freundii specifically related to one kind, so that it is removed the heavy metal cadmium in water body in situ and generates nano material precipitating, especially with respect to a kind of nutriment decomposed around culture solution by citrobacter freundii, to generate a large amount of acid ion, part acid ion such as carbonic acid with, phosphate radical etc. is reacted with heavy metal cadmium, form cadmium nanoscale precipitating, it is also synthesized accordingly while removal Heavy Metals in Waters cadmium every nano metal material to reach.

Description

A kind of citrobacter freundii goes cadmium and the method for generating nano material in water removal

Technical field

It the present invention relates to the use of microculture, water body purification, nano material synthesis technical field, and in particular to one kind By cultivating citrobacter freundii, it is made to remove the heavy metal cadmium in water body in situ and generating nano material precipitating, especially About a kind of nutriment decomposed around culture solution by citrobacter freundii, to generate a large amount of acid ion, portion Point acid ion such as carbonic acid is reacted with, phosphate radical etc. with heavy metal cadmium, cadmium nanoscale precipitating is formed, to reach removal Corresponding cadmium nano metal material is also synthesized while Heavy Metals in Waters cadmium.

Background technique

Heavy metal pollution in present China water body is particularly acute, and the pollution of Heavy Metals in Waters is more headed by cadmium pollution Number be due to the exploitation of metal resource, the discharge of chemical industry factory production waste water, farmland fertilizer be excessively used and the tail of automobile Gas.Exist in the form of an ion because heavy metal is most in the liquid phase, this form can be by plant, animal, human consumption to body It is interior, and constantly accumulation in vivo, finally it is detrimental to health.It is logical that the method for previous activated sludge, which removes removing heavy metals majority, It crosses zoogloea to be complexed with the protein that extremely strong adsorptivity and microorganism generate with heavy metal, thus by heavy metals removal. This mode exists to the halfway problem of heavy metals removal, mainly since zoogloea can be due to bacterium surrounding nutrient substance It reduces and disappears, the heavy metal that zoogloea adsorbs after disappearance is released into water again；Heavy metal and protein complexation stroke Chelate can be decomposed by Institute of Micro-biology, and complex compound is not present after decomposition, and heavy metal is released into water again.The present invention is directed to mention For the new degradation pathway of a kind of pair of heavy metal, heavy metal is converted to stable deposit or minerals, in this way with micro- The death of biology, the heavy metal of removal can't reenter in water, but exist in the form of stable precipitating, this precipitating It can collect and be utilized again as nano material, and this removing method can also be generalized in soil, solve soil The problem of middle heavy metal difficulty removes.

Summary of the invention

It is an object of the invention to the degradations for metal to provide new idea and method, and can apply and contain weight it In metal water process or heavy-metal contaminated soil reparation.

To achieve the above object, the present invention takes with scheme:

(1) the citrobacter freundii reference culture (ATCC43864) of initial strain source Yu Guo house fungus library purchase.

(2) peptone, 5g beef extract, 5g sodium chloride, the 40mg caddy for weighing 10g, are dissolved in going for 1000ml In ionized water, after the pH to neutrality of sodium hydrate regulator solution is added, the peptone containing caddy 40mg/L, beef are made Cream culture medium (hereinafter has culture medium of the metal without phosphate), puts it into high-pressure steam sterilizing pan and goes out at 121 DEG C It after bacterium 30min, takes out and is placed in aseptic operating platform, be inoculated with after dropping to room temperature with citric acid bacillus.

(3) peptone, 5g beef extract, 5g sodium chloride, 40mg caddy, the five water phosphoglyceride two of 116mg of 10g are weighed Sodium (molar ratio with cadmium is 1:2), is dissolved in the deionized water of 1000ml, the pH of sodium hydrate regulator solution is added extremely After neutrality, make containing caddy 40mg/L, the peptone of phosphoglyceride disodium 116mg/L, beef extract culture medium (hereinafter The culture medium for referred to as thering is metal to have phosphate), after putting it into high-pressure steam sterilizing pan the 30min that sterilizes at 121 DEG C, take out It is placed in aseptic operating platform, is inoculated with after dropping to room temperature with citric acid bacillus.

(4) will have metal have phosphate, have culture medium of the metal without phosphate in aseptic operating platform fall 150ml in In the conical flask of 250ml, choose from standard citrobacter freundii bacterial strain it is several, be inoculated in pour out there is metal to have phosphoric acid Ester has metal without in the culture medium of phosphate.

(5) by after inoculation to have metal to have phosphate, have metal to be placed in temperature without the culture medium of phosphate be 35 DEG C In shaking table, after culture 6 days, precipitating is extracted out, bacterium solution is taken out.

(6) citrobacter freundii and citrobacter freundii after being tamed after taking out are in Wu Wushui phosphoglycerol The cadmium carbonate that synthesizes under the conditions of ester disodium has the cadmium rock phosphate synthesized under the conditions of five water phosphoglyceride disodiums, this kind domestication can To be repeated as many times, the more citrobacter freundiis of number are stronger to the adaptability of cadmium.

Detailed description of the invention

Fig. 1 citrobacter freundii electron microscope (1000 times of amplification) screenshot

35 DEG C of Fig. 2, there is metal to have phosphate, have culture medium of the metal without phosphate to the removal effect figure of cadmium

Fig. 3 has metal to precipitate XRD retrieval figure without the culture medium of phosphate

The culture medium precipitating XRD retrieval figure that Fig. 4 has metal to have phosphate

Fig. 5 cadmium carbonate electron lens figure

Fig. 6 cadmium rock phosphate electron lens figure

Specific embodiment

1. weigh the peptone of 10g, 5g beef extract, 5g sodium chloride, 40mg caddy, be dissolved in 1000ml go from In sub- water, after the pH to neutrality of sodium hydrate regulator solution is added, the peptone containing caddy 40mg/L, beef extract are made Culture medium (hereinafter has culture medium of the metal without phosphate), puts it into high-pressure steam sterilizing pan and sterilizes at 121 DEG C It after 30min, takes out and is placed in aseptic operating platform, be inoculated with after dropping to room temperature with citric acid bacillus.

2. weighing the peptone of 10g, 5g beef extract, 5g sodium chloride, 40mg caddy, five water phosphoglyceride two of 116mg Sodium (molar ratio with cadmium is 1:2), is dissolved in the deionized water of 1000ml, the pH of sodium hydrate regulator solution is added extremely After neutrality, make containing caddy 40mg/L, the peptone of phosphoglyceride disodium 116mg/L, beef extract culture medium (hereinafter The culture medium for referred to as thering is metal to have phosphate), after putting it into high-pressure steam sterilizing pan the 30min that sterilizes at 121 DEG C, take out It is placed in aseptic operating platform, is inoculated with after dropping to room temperature with citric acid bacillus.

3. will there is metal to have phosphate, there is culture medium of the metal without phosphate to fall 150ml in aseptic operating platform in 250ml Conical flask in, choose from standard citrobacter freundii bacterial strain it is several, be inoculated in pour out there is metal to have phosphate, have gold Belong in the culture medium without phosphate.

4. by thering is metal to have phosphate, there is metal without the culture medium of phosphate to be placed in temperature and be 35 DEG C to shake after inoculation In bed, after culture 6 days, precipitating is extracted out, bacterium solution is taken out.

Fig. 1 shows shape appearance figure of citrobacter freundii under the conditions of amplifying 1000 times, hence it is evident that it can be seen that at bar Shape, and there are many quantity；Fig. 2 is at 35 DEG C, sustaining degradation 6 days, and finally having metal to have one group of chlorination cadmium concentration of phosphate is 0, drop Solution efficiency reaches 100%, and having metal without one group of chlorination cadmium concentration of phosphate is 5mg/L, and degradation effect reaches 87.5%；Fig. 3 is There is metal XRD and to retrieve, obtained search result without testing after the precipitating drying of phosphate, from result, it is apparent that The peak of standard substance cadmium carbonate compares that matching degree is very high with unknown materials, so determination has metal to be precipitated as carbonic acid without phosphate Cadmium；Fig. 4 is to test XRD after having metal to have the precipitating of phosphate to dry and retrieve, and obtained search result can be bright from result Aobvious to find out, peak and the unknown materials of standard substance cadmium rock phosphate compare that matching degree is very high, and main peak corresponds so determining has Metal is precipitated as cadmium carbonate without phosphate；Fig. 5 is the TEM test chart for having precipitating of the metal without phosphate, it is seen that the carbon of formation Sour cadmium pattern is in vertical bar textured, similar to the texture of wood, regular shape；Fig. 6 be have metal have phosphate precipitating TEM Test chart, it is seen that the cadmium rock phosphate of stroke is spherical, and close-packed arrays, and size is uniform, and ball diameter is in 40nm.

In conclusion this method after eliminating the heavy metal cadmium in water body, also prepare a nanometer cadmium material cadmium carbonate, Cadmium rock phosphate, pattern is different, has reached the utilization again to cadmium, converts toxic substance to nontoxic cadmium metal nanometer material Material.

Claims

1. a kind of citrobacter freundii removes heavy metal cadmium and the method for generating cadmium nano metal material in water removal, specific method It is by cultivating citric acid bacillus in the culture medium for having heavy metal cadmium, to reach the mesh removed in situ to heavy metal cadmium , and generate the metal nano material containing cadmium.

2. the content according to claim 1, citrobacter freundii is the reference culture bought from state's house fungus library, i.e. Freund Citric acid bacillus (ATCC43864).

3. the content according to claim 1, citrobacter freundii without containing phosphoglyceride disodium and contains containing cadmium respectively It is cultivated in the fluid nutrient medium that cadmium contains phosphoglyceride disodium.

4. having formula and inoculation operation of the metal without containing phosphoglyceride disodium culture medium according to the content in claim 3 Are as follows: peptone, 5g beef extract, 5g sodium chloride, the 40mg caddy for weighing 10g are dissolved in the deionized water of 1000ml, After the pH to neutrality of sodium hydrate regulator solution is added, the peptone containing caddy 40mg/L, beef extract culture medium are made (hereinafter having culture medium of the metal without phosphate), puts it into the 30min that sterilizes at 121 DEG C in high-pressure steam sterilizing pan Afterwards, it takes out and is placed in aseptic operating platform, be inoculated with after dropping to room temperature with citric acid bacillus；There is metal to contain phosphoglyceride disodium The formula of culture medium and inoculation operation are as follows: weigh peptone, 5g beef extract, 5g sodium chloride, 40mg caddy, the 116mg five of 10g Water phosphoglyceride disodium (molar ratio with cadmium is 1:2), is dissolved in the deionized water of 1000ml, sodium hydroxide is added After the pH to neutrality for adjusting solution, make containing caddy 40mg/L, the peptone of phosphoglyceride disodium 116mg/L, ox Meat extract culture medium (hereinafter has metal to have the culture medium of phosphate), puts it into high-pressure steam sterilizing pan at 121 DEG C It sterilizes after 30min, takes out and be placed in aseptic operating platform, be inoculated with after dropping to room temperature with citric acid bacillus.

5. bacterium is placed in shaking table after inoculation according to the content in claim 4, set temperature is 35 DEG C, is cultivated 6 days.

6. having metal according to the content in claim 4 without phosphoglyceride disodium and thering is metal to have phosphoglyceride disodium Culture medium prescription can increase or reduce simultaneously identical multiple, be conveniently used for small-scale or large-scale culture.

7. cadmium metal concentration can be decreased obviously after 6 days, and have metal without phosphoglyceride according to the content in claim 5 Cadmium carbonate is generated in disodium culture medium, has metal to have generation cadmium rock phosphate in phosphoglyceride disodium culture medium.