A river and lake sediment in-situ ecological restoration agent and its preparation process

Abstract

The invention provides an in-situ ecological restoration agent for river and lake sediment and a preparation process thereof. The in-situ ecological restoration agent for river and lake sediment is mainly composed of the following raw materials in parts by mass: 15-30 parts of coconut shell granular activated carbon, 40-50 parts of montmorillonite particles, 10-20 parts of macroporous anion exchange resin D301, 10-20 parts of macroporous cation exchange resin D113, 5-20 parts of column chromatography silica gel, 5-10 parts of polyethylene glycol, 10-15 parts of dimercaptosuccinic acid, 5-10 parts of ethylenediaminetetraacetic acid, 10-20 parts of carboxyl nitrile rubber modified SBS elastomer and 4-5 parts of crown ether carboxylic acid. The repair agent of the present invention utilizes the principles of physical and chemical stabilization and repair to stabilize and solidify heavy metal ions in river and lake sediments in the repair agent, and at the same time reduces the mobility and toxicity of heavy metal ions through chemical reaction changes, thereby ensuring that the removal rate of heavy metal ions in river and lake sediments after repair reaches more than 95%, and is stable for a long time without release and precipitation, thus meeting the needs of subsequent harmless treatment and resource utilization of the sediment.

Description

Technical Field

[0001] An in-situ ecological restoration agent for river and lake sediments and a preparation process thereof. Background Art

[0002] Bottom mud is the sediment of rivers and lakes and an important part of natural waters. When waters are polluted, some pollutants in the water can be stored in the bottom mud through precipitation or adsorption of particulate matter, and released again under appropriate conditions, becoming a secondary pollution source. With the development of the economy, a large number of rivers in cities are in a semi-closed state, with a large amount of pollution and poor water quality. Through data research and on-site investigation, the pollution characteristics of water bodies are that the water bodies are polluted by oxygen-consuming organic matter, nutrients such as nitrogen and phosphorus, and heavy metals, while the bottom mud is a reservoir of nutrients such as nitrogen and phosphorus, organic matter, and heavy metals, and the water ecology is damaged.

[0003] At present, the methods commonly used to treat heavy metals in river and lake sediments are metal integration and heavy metal solidification and stabilization. However, the cost of the metal integration method is relatively high, and the integration process itself has certain limitations, which makes it impossible to promote and use it on a large scale in the treatment of heavy metals in river and lake sediments. The heavy metal solidification and stabilization technology has uneven stabilization effects for heavy metal ions in different environments, concentrations, and types, and the stability after solidification is not strong. At the same time, the addition of water-hardening materials for solidification will also bring about hardening and increment problems, which is not conducive to the subsequent resource disposal and utilization of sediments.

[0004] Therefore, there is an urgent need for an in-situ ecological restoration agent for river and lake sediments and a preparation process thereof to solve the deficiencies of the existing technical problems. Summary of the invention

[0005] The present invention mainly provides an in-situ ecological restoration agent for river and lake sediments and a preparation method thereof, so as to solve the problem that the current river and lake sediment treatment methods are not conducive to the subsequent resource disposal and utilization of the sediments.

[0006] According to one aspect of the present invention, there is provided an in-situ ecological restoration agent for river and lake sediments, which is mainly composed of the following raw materials in parts by mass: 15-30 parts of coconut shell granular activated carbon, 40-50 parts of montmorillonite particles, 10-20 parts of anion exchange resin, 10-20 parts of cation exchange resin, 5-20 parts of column chromatography silica gel, 5-10 parts of polyethylene glycol, 10-15 parts of dimercaptosuccinic acid, 5-10 parts of ethylenediaminetetraacetic acid, 10-20 parts of carboxyl nitrile rubber modified SBS elastomer and 4-5 parts of crown ether carboxylic acid.

[0007] Preferably, the coconut shell activated carbon particles are 3-5 mm coconut shell activated carbon particles.

[0008] Preferably, the montmorillonite particles are high-purity montmorillonite ore particles.

[0009] Preferably, the anion exchange resin is macroporous anion exchange resin D301.

[0010] Preferably, the cation exchange resin is macroporous cation exchange resin D113.

[0011] Preferably, the column chromatography silica gel is 60-100 mesh column chromatography silica gel particles.

[0012] Preferably, the polyethylene glycol is polyethylene glycol 400.

[0013] Preferably, the dimercaptosuccinic acid is industrial grade dimercaptosuccinic acid.

[0014] Preferably, the ethylenediaminetetraacetic acid is industrial grade ethylenediaminetetraacetic acid.

[0015] Preferably, the carboxylated nitrile rubber modified SBS elastomer is 10-20 mesh carboxylated nitrile rubber modified SBS elastomer particles.

[0016] Preferably, the crown ether carboxylic acid is 4-benzo-18-crown-6 carbonate.

[0017] According to another aspect of the present invention, there is also provided a method for preparing an in-situ ecological restoration agent for river and lake sediments, comprising the following steps:

[0018] S1, adding the formulated amount of carboxylated nitrile rubber modified SBS elastomer particles and polyethylene glycol 400 to ethylene glycol, adding thionyl chloride dropwise under stirring, and heating for reaction after the addition is completed, which is recorded as the first mixed system;

[0019] S2, adding ethylenediaminetetraacetic acid, 4-benzo-18-crown-6 carbonate and dithiosuccinic acid to the first mixed system obtained in step S1, mechanically stirring to dissolve, adding thionyl chloride dropwise under stirring, heating for reaction, filtering, and obtaining carboxylated nitrile rubber modified SBS elastomer composite ester particles;

[0020] S3, spray water to wet the coconut shell granular activated carbon, evenly sprinkle column chromatography silica gel on the surface of the coconut shell granular activated carbon, and shake it to mix and bond it to obtain a coconut shell granular activated carbon-column chromatography silica gel mixture;

[0021] S4, the carboxylated nitrile rubber modified SBS elastomer composite ester particles obtained in step S2, the coconut shell granular activated carbon-column chromatography silica gel mixture obtained in step S3, montmorillonite particles, anion exchange resin, and cation exchange resin are mixed evenly, put into a nylon bag, and then put into the polyhedral hollow ball.

[0022] Preferably, in step S1, the heating temperature is 55-65° C. and the reaction time is 3 h.

[0023] Preferably, in step S1, the amount of ethylene glycol used is 4 times the weight of the carboxylated nitrile rubber modified SBS elastomer particles.

[0024] Preferably, in step S2, the heating temperature is 55-65° C. and the reaction time is 2-3 h.

[0025] Preferably, both step S1 and step S2 are performed under a nitrogen protection environment.

[0026] Preferably, the polyhedral hollow spheres in step S4 are polyethylene polyhedral hollow spheres.

[0027] The in-situ ecological restoration agent for river and lake bottom mud and the preparation method thereof have the following beneficial effects: the restoration agent utilizes the physical and chemical stable restoration principle, fixes polyethylene glycol to the surface of carboxylated nitrile rubber modified SBS elastomer particles through an esterification reaction, and then performs an esterification reaction on crown ether, ethylenediaminetetraacetic acid, dimercaptosuccinic acid and the hydroxyl group carried by polyethylene glycol to obtain carboxylated nitrile rubber modified SBS elastomer composite ester particles, which can improve the adsorption capacity of heavy metals on the one hand, and reduce the introduction of harmful substances on the other hand; by cooperating with montmorillonite particles, heavy metal ions in aqueous solution can be quickly removed, and the restoration effect on river and lake bottom mud can be improved; by adding anion and cation exchange resins and column chromatography silica gel, nitrogen and phosphorus compounds and other harmful ion groups in river and lake bottom mud can be adsorbed, and the restoration effect can be improved; by adding coconut shell granular activated carbon, on the one hand, the restoration effect on organic pollutants and heavy metals can be improved, and on the other hand, deodorization can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The present invention is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0029] Figure 1 Polyethylene multi-faceted hollow sphere diagram for in-situ ecological restoration of river and lake sediments used in river and lake management; DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] Example 1

[0032] 150g coconut shell granular activated carbon, 400g montmorillonite granules, 100g anion exchange resin, 100g cation exchange resin, 50g column chromatography silica gel, 50g polyethylene glycol, 100g dimercaptosuccinic acid, 50g ethylenediaminetetraacetic acid, 100g carboxylated nitrile rubber modified SBS elastomer, 40g crown ether carboxylic acid.

[0033] S1, adding the formulated amount of carboxylated nitrile rubber modified SBS elastomer particles and polyethylene glycol 400 to 400g of ethylene glycol, adding thionyl chloride dropwise under nitrogen protection and stirring, heating at 55°C for 3h after the addition is complete, and recording as the first mixed system;

[0034] S2, adding the formulated amount of ethylenediaminetetraacetic acid, 4-benzo-18-crown-6 carbonate and dimercaptosuccinic acid to the first mixed system obtained in step S1, protecting with nitrogen, mechanically stirring to dissolve, adding thionyl chloride dropwise under stirring, heating at 55° C. for 3 h, filtering, and obtaining carboxylated nitrile rubber modified SBS elastomer composite ester particles;

[0035] S3, spray water to wet the coconut shell granular activated carbon in the formula, evenly sprinkle column chromatography silica gel on the surface of the coconut shell granular activated carbon, shake it to mix and bond it, and obtain a coconut shell granular activated carbon-column chromatography silica gel mixture;

[0036] S4, the carboxylated nitrile rubber modified SBS elastomer composite ester particles obtained in step S2, the coconut shell granular activated carbon-column chromatography silica gel mixture obtained in step S3, montmorillonite particles, anion exchange resin, and cation exchange resin are mixed evenly, put into a nylon bag, and then put into a polyethylene polyhedral hollow ball. Figure 1 shown.

[0037] Example 2

[0038] 200g coconut shell granular activated carbon, 450g montmorillonite granules, 150g anion exchange resin, 150g cation exchange resin, 150g column chromatography silica gel, 70g polyethylene glycol, 120g dimercaptosuccinic acid, 70g ethylenediaminetetraacetic acid, 150g carboxylated nitrile rubber modified SBS elastomer, 45g crown ether carboxylic acid.

[0039] S1, adding the formulated amount of carboxylated nitrile rubber modified SBS elastomer particles and polyethylene glycol 400 to 600g of ethylene glycol, adding thionyl chloride dropwise under nitrogen protection and stirring, and heating at 60°C for 3h after the addition is complete, which is recorded as the first mixed system;

[0040] S2, adding the formulated amount of ethylenediaminetetraacetic acid, 4-benzo-18-crown-6 carbonate and dimercaptosuccinic acid to the first mixed system obtained in step S1, protecting with nitrogen, mechanically stirring to dissolve, adding thionyl chloride dropwise under stirring, heating at 60° C. for 3 h, filtering, and obtaining carboxylated nitrile rubber modified SBS elastomer composite ester particles;

[0041] S3, spray water to wet the coconut shell granular activated carbon in the formula, evenly sprinkle column chromatography silica gel on the surface of the coconut shell granular activated carbon, shake it to mix and bond it, and obtain a coconut shell granular activated carbon-column chromatography silica gel mixture;

[0042] S4, the carboxylated nitrile rubber modified SBS elastomer composite ester particles obtained in step S2, the coconut shell granular activated carbon-column chromatography silica gel mixture obtained in step S3, montmorillonite particles, anion exchange resin, and cation exchange resin are mixed evenly, put into a nylon bag, and then put into a polyethylene polyhedral hollow ball. Figure 1 shown.

[0043] Example 3

[0044] 300g coconut shell granular activated carbon, 500g montmorillonite granules, 200g anion exchange resin, 200g cation exchange resin, 200g column chromatography silica gel, 100g polyethylene glycol, 150g dimercaptosuccinic acid, 100g ethylenediaminetetraacetic acid, 200g carboxylated nitrile rubber modified SBS elastomer, 50g crown ether carboxylic acid.

[0045] S1, adding the formulated amount of carboxylated nitrile rubber modified SBS elastomer particles and polyethylene glycol 400 to 800g of ethylene glycol, adding thionyl chloride dropwise under nitrogen protection and stirring, and heating at 65°C for 3h after the addition is complete, which is recorded as the first mixed system;

[0046] S2, adding the formulated amount of ethylenediaminetetraacetic acid, 4-benzo-18-crown-6 carbonate and dimercaptosuccinic acid to the first mixed system obtained in step S1, protecting with nitrogen, mechanically stirring to dissolve, adding thionyl chloride dropwise under stirring, heating at 65° C. for 3 h, filtering, and obtaining carboxylated nitrile rubber modified SBS elastomer composite ester particles;

[0047] S3, spray water to wet the coconut shell granular activated carbon in the formula, evenly sprinkle column chromatography silica gel on the surface of the coconut shell granular activated carbon, shake it to mix and bond it, and obtain a coconut shell granular activated carbon-column chromatography silica gel mixture;

[0048] S4, the carboxylated nitrile rubber modified SBS elastomer composite ester particles obtained in step S2, the coconut shell granular activated carbon-column chromatography silica gel mixture obtained in step S3, montmorillonite particles, anion exchange resin, and cation exchange resin are mixed evenly, put into a nylon bag, and then put into a polyethylene polyhedral hollow ball. Figure 1 shown.

[0049] Example 4

[0050] 150g coconut shell granular activated carbon, 400g montmorillonite granules, 200g anion exchange resin, 200g cation exchange resin, 200g column chromatography silica gel, 100g polyethylene glycol, 150g dimercaptosuccinic acid, 100g ethylenediaminetetraacetic acid, 200g carboxylated nitrile rubber modified SBS elastomer, 50g crown ether carboxylic acid.

[0051] S1, adding the formulated amount of carboxylated nitrile rubber modified SBS elastomer particles and polyethylene glycol 400 to 800g of ethylene glycol, adding thionyl chloride dropwise under nitrogen protection and stirring, and heating at 60°C for 3h after the addition is complete, which is recorded as the first mixed system;

[0052] S2, adding the formulated amount of ethylenediaminetetraacetic acid, 4-benzo-18-crown-6 carbonate and dimercaptosuccinic acid to the first mixed system obtained in step S1, protecting with nitrogen, mechanically stirring to dissolve, adding thionyl chloride dropwise under stirring, heating at 60° C. for 3 h, filtering, and obtaining carboxylated nitrile rubber modified SBS elastomer composite ester particles;

[0053] S3, spray water to wet the coconut shell granular activated carbon in the formula, evenly sprinkle column chromatography silica gel on the surface of the coconut shell granular activated carbon, shake it to mix and bond it, and obtain a coconut shell granular activated carbon-column chromatography silica gel mixture;

[0054] S4, the carboxylated nitrile rubber modified SBS elastomer composite ester particles obtained in step S2, the coconut shell granular activated carbon-column chromatography silica gel mixture obtained in step S3, montmorillonite particles, anion exchange resin, and cation exchange resin are mixed evenly, put into a nylon bag, and then put into a polyethylene polyhedral hollow ball. Figure 1 shown.

[0055] Example 5

[0056] 300g coconut shell granular activated carbon, 500g montmorillonite granules, 100g anion exchange resin, 100g cation exchange resin, 50g column chromatography silica gel, 50g polyethylene glycol, 100g dimercaptosuccinic acid, 50g ethylenediaminetetraacetic acid, 100g carboxylated nitrile rubber modified SBS elastomer, 40g crown ether carboxylic acid.

[0057] S1, adding the formulated amount of carboxylated nitrile rubber modified SBS elastomer particles and polyethylene glycol 400 to 400g of ethylene glycol, adding thionyl chloride dropwise under nitrogen protection and stirring, and heating at 60°C for 3h after the addition is complete, which is recorded as the first mixed system;

[0058] S2, adding the formulated amount of ethylenediaminetetraacetic acid, 4-benzo-18-crown-6 carbonate and dimercaptosuccinic acid to the first mixed system obtained in step S1, protecting with nitrogen, mechanically stirring to dissolve, adding thionyl chloride dropwise under stirring, heating at 60° C. for 3 h, filtering, and obtaining carboxylated nitrile rubber modified SBS elastomer composite ester particles;

[0059] S3, spray water to wet the coconut shell granular activated carbon in the formula, evenly sprinkle column chromatography silica gel on the surface of the coconut shell granular activated carbon, shake it to mix and bond it, and obtain a coconut shell granular activated carbon-column chromatography silica gel mixture;

[0060] S4, the carboxylated nitrile rubber modified SBS elastomer composite ester particles obtained in step S2, the coconut shell granular activated carbon-column chromatography silica gel mixture obtained in step S3, montmorillonite particles, anion exchange resin, and cation exchange resin are mixed evenly, put into a nylon bag, and then put into a polyethylene polyhedral hollow ball. Figure 1 shown.

[0061] Comparative Example 1

[0062] Same as Example 1, except that dimercaptosuccinic acid, ethylenediaminetetraacetic acid and crown ether carboxylic acid are not added.

[0063] Comparative Example 2

[0064] Same as Example 1, except that no anion exchange resin, cation exchange resin and column chromatography silica gel are added.

[0065] Comparative Example 3

[0066] Same as Example 1, except that no montmorillonite particles are added.

[0067] Mainly containing Cd, Cu, Cr, Pb, Hg, As, NO3 - PO4 3- The polluted river and lake sediment samples were taken as the repair treatment objects, and the repair agents of Examples 1 to 5 and Comparative Examples 1 to 3 were added respectively. The added repair dosage was 5% of the mass of the treated sediment (calculated based on a water content of 60%). The placement time after addition was 7 days. The leaching experiment was carried out according to the national HJ / T 299 solid waste leaching toxicity leaching method. The specific results are shown in Table 1 below.

[0068] Table 1 Comparison of the results of the examples and comparative examples

[0069]

[0070] It can be seen from Table 1 that the pollutants in the river and lake sediments are greatly reduced after restoration using the river and lake sediment in-situ ecological restoration agent of the present application. Comparative Example 1 shows that dimercaptosuccinic acid, ethylenediaminetetraacetic acid and crown ether carboxylic acid can complex heavy metal ions to a greater extent. The data from Comparative Example 2 show that anion exchange resin, cation exchange resin and column chromatography silica gel can remove nitrogen and phosphorus pollutants to a greater extent. Comparative Example 3 shows that montmorillonite particles can also have an adsorption and removal effect on heavy metal ions. This shows that the river and lake sediment in-situ ecological restoration agent of the present invention can not only remove heavy metal pollutants, but also remove nitrogen and phosphorus pollutants, and the restoration effect is relatively ideal.

[0071] Of course, the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by ordinary technicians in this technical field within the essential scope of the present invention also fall within the protection scope of the present invention.

Claims

1. An in-situ ecological restoration agent for river and lake sediments, characterized in that: The invention is mainly composed of the following raw materials in parts by weight: 15-30 parts of coconut shell granular activated carbon, 40-50 parts of montmorillonite particles, 10-20 parts of anion exchange resin, 10-20 parts of cation exchange resin, 5-20 parts of column chromatography silica gel, 5-10 parts of polyethylene glycol, 10-15 parts of dimercaptosuccinic acid, 5-10 parts of ethylenediaminetetraacetic acid, 10-20 parts of carboxylated nitrile rubber modified SBS elastomer and 4-5 parts of crown ether carboxylic acid; The preparation method of the river and lake bottom mud in-situ ecological restoration agent is as follows: S1, adding the formulated amount of carboxylated nitrile rubber modified SBS elastomer particles and polyethylene glycol 400 to ethylene glycol, adding thionyl chloride dropwise under stirring, and heating for reaction after the addition is completed, which is recorded as the first mixed system; S2, adding ethylenediaminetetraacetic acid, 4-benzo-18-crown-6 carbonate and dithiosuccinic acid to the first mixed system obtained in step S1, mechanically stirring to dissolve, adding thionyl chloride dropwise under stirring, heating for reaction, filtering, and obtaining carboxylated nitrile rubber modified SBS elastomer composite ester particles; S3, spray water to wet the coconut shell granular activated carbon, evenly sprinkle column chromatography silica gel on the surface of the coconut shell granular activated carbon, and shake it to mix and bond it to obtain a coconut shell granular activated carbon-column chromatography silica gel mixture; S4, the carboxylated nitrile rubber modified SBS elastomer composite ester particles obtained in step S2, the coconut shell granular activated carbon-column chromatography silica gel mixture obtained in step S3, montmorillonite particles, anion exchange resin, and cation exchange resin are mixed evenly, put into a nylon bag, and then put into the polyhedral hollow ball.

2. The in-situ ecological restoration agent for river and lake sediments according to claim 1, characterized in that: The coconut shell activated carbon particles are 3-5 mm coconut shell activated carbon particles; The montmorillonite particles are high-purity montmorillonite ore particles; The anion exchange resin is macroporous anion exchange resin D301; The cation exchange resin is macroporous cation exchange resin D113; The column chromatography silica gel is 60-100 mesh column chromatography silica gel particles; The polyethylene glycol is polyethylene glycol 400; The dimercaptosuccinic acid is industrial grade dimercaptosuccinic acid; The ethylenediaminetetraacetic acid is industrial grade ethylenediaminetetraacetic acid; The carboxylated nitrile rubber modified SBS elastomer is carboxylated nitrile rubber modified SBS elastomer particles; The crown ether carboxylic acid is 4-benzo-18-crown-6 carbonate.

3. The in-situ ecological restoration agent for river and lake sediments according to claim 1, characterized in that: In the step S1, the heating temperature is 55-65° C. and the reaction time is 2-3 hours.

4. The in-situ ecological restoration agent for river and lake sediments according to claim 1, characterized in that: In the step S1, the amount of ethylene glycol used is 4 times the weight of the carboxylated nitrile rubber modified SBS elastomer particles.

5. The in-situ ecological restoration agent for river and lake sediments according to claim 1, characterized in that: In step S2, the heating temperature is 55-65° C. and the reaction time is 2-3 hours.

6. The in-situ ecological restoration agent for river and lake sediments according to claim 3, characterized in that: The steps S1 and S2 are both performed under a nitrogen protection environment.

7. The in-situ ecological restoration agent for river and lake sediments according to claim 1, characterized in that: The polyhedral hollow spheres in step S4 are polyethylene polyhedral hollow spheres.

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