CN115286119A - A kind of microbial strengthening agent for removing hexavalent chromium using mineral/biomass as carrier and preparation method thereof - Google Patents

Abstract

The invention discloses a microorganism strengthening agent for removing hexavalent chromium by taking minerals/biomass as a carrier and a preparation method thereof, wherein the microorganism strengthening agent is prepared from the following raw materials: clay minerals, waste biomass, microbial feedstocks. The invention combines the waste biomass material and the clay mineral, and adopts the immobilization technology to coat microbial strains, thereby providing long-acting nutrient sources for the microbes, increasing the biomass and improving the capability of removing hexavalent chromium.

Description

A microbial enhancement drug for removing hexavalent chromium with mineral/biomass as carrier Agents and their preparation methods

technical field

The invention belongs to a microbial enhancement agent for removing hexavalent chromium with mineral/biomass as a carrier and a preparation method thereof, in particular to a microbial enhancement agent for removal of hexavalent chromium with mineral/biomass as a carrier and its Preparation.

Background technique

The traditional treatment of heavy metals with flocculants, ion exchange methods, electrochemical methods, and biomass adsorbents has high cost, narrow application range, inconsistent stability, and easy to cause secondary pollution. Microbial enhancement technology is to add carbon sources, nitrogen sources and other nutrient sources and electron donors, which can not only increase microbial biomass, but also restore heavy metals in water and soil. Adding nutrients from exogenous sources can assist the growth of microorganisms, but the structure is relatively simple and the time limit is not long, and it is easy to be washed away by rainwater during soil restoration and treatment. Clay minerals are powerful adsorbents and can act as electron donors for microorganisms, providing nutrients for microorganisms.

With the development of industrialization, the heavy metal content in many chemical plants, industrial clusters and surrounding soil and water sources exceeds the standard, causing serious damage to plants and animals, and eventually enters the human body through the food chain, causing various diseases. Microbial remediation is an environmentally friendly technology. Microbial stimulants can utilize exogenously added nutritional substrates, surfactants, and organic modifiers to strengthen microorganisms.

Contents of the invention

The purpose of the present invention is to provide a microbial enhancement agent for removing hexavalent chromium with mineral/biomass as a carrier and its preparation method, which solves the problem of low efficiency of microorganisms in the prior art for removing hexavalent chromium.

In order to achieve the above object, the present invention adopts the following technical solutions:

A kind of mineral/biomass is used as the preparation method of the microbiological strengthening agent that removes hexavalent chromium, comprises the steps:

Step 1, placing Stenotrophomonas in LB medium to obtain microbial bacterial liquid;

Step 2, treating the waste biomass raw material with sodium hydroxide, drying, crushing, and sieving;

Step 3, grinding and sieving the clay mineral raw material, modifying the clay mineral, drying and finally sieving;

Step 4, configure sodium alginate solution, mix the raw materials in step 2 and step 3 into the sodium alginate solution in proportion; sterilize at 120°C for 15 minutes, and after cooling to room temperature, add the Microbial bacteria liquid, dripped into 4% calcium chloride solution with a syringe, cross-linked for 8 hours, rinsed with normal saline, and obtained immobilized pellets;

Step 5. Gelatinize the starch at 80°C to make a starch solution, pour the gelatin powder into distilled water to make a gelatin solution, mix the above starch solution and gelatin solution at a ratio of 9:1, and then sterilize at 120°C for 15 minutes. The immobilized pellets obtained in step 4 were placed in the mixed solution, and cross-linked for 12 hours to obtain the microbial enhancement agent.

Preferably, the concentration of the sodium hydroxide solution in the step 2 is 0.2%-2%.

Preferably, the clay mineral raw material in step 3 is kaolin.

Preferably, the raw material ratio of the waste biomass raw material treated with sodium hydroxide and the modified clay mineral in step 4 is 3:1.

Preferably, the method for modifying clay minerals in the step 3 is: add chitosan in the acetic acid solution, stir until completely dissolved, add clay minerals and stir in the configured chitosan acetic acid solution in distilled water, and dissolve the solution Adjust the pH to 10, add glutaraldehyde solution, crosslink for 24 hours, wash with distilled water to pH 7 after suction filtration, and dry naturally.

Preferably, the ratio of clay mineral to distilled water is 1g:10ML.

Another technical solution adopted in the present invention: a microbial enhancement agent that uses minerals/biomass as a carrier to remove hexavalent chromium, prepared from the following raw materials: modified clay minerals, waste treated with sodium hydroxide Biomass raw material, Stenotrophomonas, sodium alginate, calcium chloride, starch solution and gelatin solution.

Beneficial effects of the present invention: the present invention combines waste biomass materials and clay minerals, uses immobilization technology to coat microbial strains, provides long-term nutrient sources for microorganisms, increases biomass, and improves the ability to remove hexavalent chromium; The invention has the characteristics of long-term effect, low cost, green, turning waste into treasure, and using waste to control pollution.

Description of drawings

Fig. 1 is a schematic flow chart of a preparation method of a microorganism-enhanced agent for removing hexavalent chromium using mineral/biomass as a carrier in the present invention.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some of the embodiments of the present invention, but not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Example 1

A microbial enhancement agent using mineral/biomass as a carrier to remove hexavalent chromium, prepared from the following raw materials: modified clay minerals, waste biomass raw materials treated with sodium hydroxide, Stenotrophomonas, Sodium alginate, calcium chloride, starch solution and gelatin solution.

As shown in Figure 1, a kind of mineral/biomass is used as the preparation method of the microbial enhancement medicament that removes hexavalent chromium as carrier, comprises the steps:

Step 1, the microbial strains are placed in LB medium for separate culture.

Step 2, using waste biomass as raw material. Treat the straw, peanut shells, and peels with 0.2% to 2% sodium hydroxide, dry them, crush them, sieve them, and mix them evenly according to the ratio of straw, peanut shells, and peels at a ratio of 3:3:1 to obtain a mixed biomass material .

Step 3, using kaolin as the clay mineral raw material, grinding and sieving, and then modifying the clay mineral. The specific steps are as follows: add 1 g of chitosan into 50 ml of 2% acetic acid solution, and stir until completely dissolved with a magnetic stirrer. Add 10g of clay mineral and prepared chitosan solution to 100ml of distilled water, stir for 30min, adjust the pH of the mixed solution to 10 with 0.1mol/L sodium hydroxide solution, add glutaraldehyde solution, crosslink for 24 hours, and filter with suction Finally, wash with distilled water until Ph is 7, dry and finally sieve.

Step 4, configure 4% sodium alginate solution, mix the raw materials in step 2 and step 3 into the sodium alginate solution at a ratio of 1: 1 (mixed biomass material: modified clay mineral), and use ultrasonic cleaning Mix by machine; sterilize at 120°C for 15 minutes, cool to room temperature, add 1ml of the microbial solution in step 1, drip it into 4% calcium chloride solution with a syringe, cross-link for 8 hours, and use 0.7% to 1% Washed with normal saline to obtain immobilized pellets.

Step 5, gelatinize the starch at 80°C to make a 2% starch solution, pour the gelatin powder into distilled water to make a 1% gelatin solution, mix the starch solution and the gelatin solution at a ratio of 9:1, Add 2% glycerol solution, sterilize at 120°C for 15 minutes, place the immobilized pellets obtained in step 4 in this mixed solution, and cross-link for 12 hours to obtain the microbial enhancement agent.

Example 2

A microbial enhancement agent using mineral/biomass as a carrier to remove hexavalent chromium, prepared from the following raw materials: modified clay minerals, waste biomass raw materials treated with sodium hydroxide, Stenotrophomonas, Sodium alginate, calcium chloride, starch solution and gelatin solution.

As shown in Figure 1, a kind of mineral/biomass is used as the preparation method of the microbial enhancement medicament that removes hexavalent chromium as carrier, comprises the steps:

Step 1, the microbial strains are placed in LB medium for separate culture.

Step 2, using waste biomass as raw material. Treat the straw, peanut shells, and peels with 0.2% to 2% sodium hydroxide, dry them, crush them, sieve them, and mix them evenly according to the ratio of straw, peanut shells, and peels at a ratio of 3:3:1 to obtain a mixed biomass material .

Step 3, using kaolin as the clay mineral raw material, grinding and sieving, and then modifying the clay mineral. The specific steps are as follows: add 1 g of chitosan into 50 ml of 2% acetic acid solution, and stir until completely dissolved with a magnetic stirrer. Add 10g of clay mineral and prepared chitosan solution to 100ml of distilled water, stir for 30min, adjust the pH of the mixed solution to 10 with 0.1mol/L sodium hydroxide solution, add glutaraldehyde solution, crosslink for 24 hours, and filter with suction Finally, wash with distilled water until Ph is 7, dry and finally sieve.

Step 4, configure 4% sodium alginate solution, mix the raw materials in step 2 and step 3 into the sodium alginate solution at a ratio of 2: 1 (mixed biomass material: modified clay mineral), and clean with ultrasonic waves Mix by machine; sterilize at 120°C for 15 minutes, cool to room temperature, add 1ml of the microbial solution in step 1, drip it into 4% calcium chloride solution with a syringe, cross-link for 8 hours, and use 0.7% to 1% Washed with normal saline to obtain immobilized pellets.

Step 5. Gelatinize the starch at 80°C to make a 2% starch solution, pour the gelatin powder into distilled water to make a 1% gelatin solution, mix the above two solutions at 9:1, add 2% Glycerol solution was sterilized at 120° C. for 15 minutes, and the immobilized pellets obtained in step 4 were placed in the mixed solution and cross-linked for 12 hours to obtain the microbial enhancement agent.

Example 3

A microbial enhancement agent using mineral/biomass as a carrier to remove hexavalent chromium, prepared from the following raw materials: modified clay minerals, waste biomass raw materials treated with sodium hydroxide, Stenotrophomonas, Sodium alginate, calcium chloride, starch solution and gelatin solution.

As shown in Figure 1, a kind of mineral/biomass is used as the preparation method of the microbial enhancement medicament that removes hexavalent chromium as carrier, comprises the steps:

Step 1, the microbial strains are placed in LB medium for separate culture.

Step 2, using waste biomass as raw material. Treat the straw, peanut shells, and peels with 0.2% to 2% sodium hydroxide, dry them, crush them, sieve them, and mix them evenly according to the ratio of straw, peanut shells, and peels at a ratio of 3:3:1 to obtain a mixed biomass material .

Step 3, using kaolin as the clay mineral raw material, grinding and sieving, and then modifying the clay mineral. The specific steps are as follows: add 1 g of chitosan into 50 ml of 2% acetic acid solution, and stir until completely dissolved with a magnetic stirrer. Add 10g of clay mineral and prepared chitosan solution to 100ml of distilled water, stir for 30min, adjust the pH of the mixed solution to 10 with 0.1mol/L sodium hydroxide solution, add glutaraldehyde solution, crosslink for 24 hours, and filter with suction Finally, wash with distilled water until Ph is 7, dry and finally sieve.

Step 4, configure 4% sodium alginate solution, mix the raw materials in step 2 and step 3 into the sodium alginate solution at a ratio of 3: 1 (mixed biomass material: modified clay mineral), and clean with ultrasonic waves Mix by machine; sterilize at 120°C for 15 minutes, cool to room temperature, add 1ml of the microbial solution in step 1, drip it into 4% calcium chloride solution with a syringe, cross-link for 8 hours, and use 0.7% to 1% Washed with normal saline to obtain immobilized pellets.

Step 5. Gelatinize the starch at 80°C to make a 2% starch solution, pour the gelatin powder into distilled water to make a 1% gelatin solution, mix the above two solutions at 9:1, add 2% Glycerol solution was sterilized at 120° C. for 15 minutes, and the immobilized pellets obtained in step 4 were placed in the mixed solution and cross-linked for 12 hours to obtain the microbial enhancement agent.

Experimental example 1

The microbial enhancement agent prepared in Example 1 has an effect on the pollution of hexavalent chromium in the water body, and the experimental steps are as follows:

Step 1, configure 50g/L hexavalent chromium mother liquor with potassium dichromate, set aside.

Step 2. Pour the mother liquor into the sterilized 1L LB culture solution, and configure the initial hexavalent chromium concentration as 100, 300mg/L. The microbiological strengthening agent of embodiment 1 is put into 100mL initial concentration and is in the Erlenmeyer flask of hexavalent chromium of 100,300mg/L, is pure bacteria control with Stenotrophomonas, does not add the blank agent of bacteria (except not containing Except for Stenotrophomonas, other components are the same as the microbial enhancement agent of Example 1) as a parallel control to measure the removal rate of hexavalent chromium, as shown in Table 1.

Table 1

As can be seen from Table 1, using the method of the present invention, compared with Stenotrophomonas (Stenotrophomonas), the microbial enhancement agent is higher to hexavalent chromium removal rate; When the hexavalent chromium initial concentration is 100,300mg/L, The removal rates of hexavalent chromium by the microbial enhancement agents were 88% and 59.7%, which were 4.3% and 3.4% higher than the removal rates of Stenotrophomonas.

Experimental example 2

The microbial enhancement agent prepared in Example 2 has an effect on the pollution of hexavalent chromium in the water body, and the experimental steps are as follows:

Step 1, configure 50g/L hexavalent chromium mother liquor with potassium dichromate, set aside.

Step 2. Pour the mother liquor into the sterilized 1L LB culture solution, and configure the initial hexavalent chromium concentration as 100, 300mg/L. The microbial enhancement agent of embodiment 2 (same as above-mentioned example 1 preparation method) is put into 100mL initial concentration and is in the hexavalent chromium Erlenmeyer flask of 100,300mg/L, is pure bacteria control with Stenotrophomonas, does not The blank agent added with bacteria (except for Stenotrophomonas, other ingredients are the same as the microbial enhancement agent of Example 1) was used as a parallel control, and the removal rate of hexavalent chromium was measured, as shown in Table 2.

Table 2

As can be seen from Table 2, adopt the method of the present invention, compared with Stenotrophomonas (Stenotrophomonas), microbial enhancement agent is higher to hexavalent chromium removal rate; When hexavalent chromium initial concentration is 100,300mg/L, The removal rates of hexavalent chromium by the microbial enhancement agents were 95.6% and 65.2%, which were 11.9% and 8.9% higher than the removal rates of Stenotrophomonas.

Experimental example 3

The microbial enhancement agent prepared in embodiment 3 has an effect on the pollution of hexavalent chromium in the water body, and the experimental steps are as follows:

Step 1, configure 50g/L hexavalent chromium mother liquor with potassium dichromate, set aside.

Step 2. Pour the mother liquor into the sterilized 1L LB culture solution, and configure the initial hexavalent chromium concentration as 100, 300mg/L. The microbial enhancement agent of embodiment 3 (same as above-mentioned example 1 preparation method) is put into 100mL initial concentration and is the hexavalent chromium conical flask of 100,300mg/L, is pure bacterium control with Stenotrophomonas, does not The blank agent added with bacteria (except for Stenotrophomonas, other ingredients are the same as the microbial enhancement agent in Example 1) was used as a parallel control, and the removal rate of hexavalent chromium was measured, as shown in Table 3.

table 3

As can be seen from Table 3, adopt the method of the present invention, compare with Stenotrophomonas (Stenotrophomonas), the microbial enhancement agent is higher to hexavalent chromium removal rate; When hexavalent chromium initial concentration is 100,300mg/L, The removal rates of hexavalent chromium by the microbial enhancement agents were 98% and 70.3%, which were 14.3% and 11.1% higher than the removal rates of Stenotrophomonas.

This shows that from Table 1 to Table 3, it can be seen that the proportion of ingredients in Example 3 is the best.

The invention combines waste biomass materials and clay minerals, uses immobilization technology to coat microbial strains, provides long-term nutrient sources for microorganisms, increases biomass, and improves the ability to remove hexavalent chromium. This invention has the characteristics of long-term effect, low cost, green, turning waste into treasure, and using waste to control pollution.

Although the content of the present invention has been described in detail through the above preferred embodiments, it should be understood that the above description should not be considered as limiting the present invention. Various modifications and alterations to the present invention will become apparent to those skilled in the art upon reading the above disclosure. Therefore, the protection scope of the present invention should be defined by the appended claims.

Claims (7)

1. A preparation method of a microorganism strengthening agent taking minerals/biomass as a carrier for removing hexavalent chromium is characterized by comprising the following steps:

step 1, placing stenotrophomonas in an LB culture medium to obtain a microbial liquid;

step 2, processing the waste biomass raw material by sodium hydroxide, drying in the sun, smashing and sieving;

step 3, grinding and sieving the clay mineral raw material, modifying the clay mineral, drying and finally sieving;

step 4, preparing a sodium alginate solution, and mixing the raw materials in the step 2 and the step 3 into the sodium alginate solution in proportion; sterilizing at 120 ℃ for 15min, cooling to room temperature, adding the microbial inoculum obtained in the step 1, dripping into a 4% calcium chloride solution by using an injector, crosslinking for 8h, and washing by using normal saline to obtain immobilized beads;

step 5, gelatinizing starch at 80 ℃ to prepare starch solution, pouring gelatin powder into distilled water to prepare gelatin solution, and mixing the starch solution and the gelatin solution according to the weight ratio of 9:1, sterilizing for 15min at 120 ℃, and placing the immobilized beads obtained in the step 4 in the mixed solution for crosslinking for 12h to obtain the microbial enhancing agent.

2. The method of claim 1, wherein the concentration of sodium hydroxide solution in step 2 is 0.2-2%.

3. The method for preparing a microbe-strengthening chemical using minerals/biomasses as carriers for removing hexavalent chromium according to claim 2, wherein the clay mineral material in the step 3 is kaolin.

4. The method for preparing a microbe-strengthening chemical using minerals/biomasses as carriers for removing hexavalent chromium according to claim 1, wherein the raw material ratio of the waste biomass raw material subjected to the sodium hydroxide treatment in the step 4 to the modified clay minerals is 3:1.

5. the method for preparing a mineral/biomass-based microbial enhancing agent for hexavalent chromium removal according to claim 1, wherein the clay mineral modification in the step 3 is performed by: adding chitosan into acetic acid solution, stirring to completely dissolve, adding clay mineral and prepared chitosan acetic acid solution into distilled water, stirring, adjusting pH of the solution to 10, adding glutaraldehyde solution, crosslinking for 24h, filtering, washing with distilled water until pH is 7, and naturally drying.

6. The method of claim 5, wherein the ratio of the clay mineral to distilled water is 1g:10ML.

7. The mineral/biomass-based microbial enhancing agent for hexavalent chromium removal according to any one of claims 1 to 6, which is prepared from the following raw materials: modified clay minerals, waste biomass raw materials treated by sodium hydroxide, stenotrophomonas, sodium alginate, calcium chloride, starch solution and gelatin solution.

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