CN109321254B - Plant heavy metal blocking agent and preparation method thereof - Google Patents

Abstract

The invention discloses a plant heavy metal blocking agent and a preparation method thereof, wherein the blocking agent comprises the following raw materials of selenium methionine, lysine, citric acid and iron salt. The blocking agent can block the enrichment of harmful components such as heavy metals entering a plant body from any way, and has the advantages of short period of the repairing agent, low repairing cost, economy, rapidness, simple and convenient use and obvious effect.

Description

Plant heavy metal blocking agent and preparation method thereof

Technical Field

The invention relates to the technical field of plant heavy metal and organic pollution remediation.

Background

The soil is a source of everything and is the root of human production and life. With the development of modern industry and agriculture, the harmful substances accumulated in soil are increasing continuously, the food safety problem is formed when agricultural production activities are carried out on the polluted soil, the living, the life and the like on the polluted soil can directly harm the health of human beings, besides, part of harmful cost also participates in the natural and ecological system circulation of various forms of solid, liquid, gas and the like, and the harm is caused to human bodies and the nature in a wider range.

Common pollution forms of soil include inorganic pollution and organic pollution, wherein the inorganic pollution is most obvious and most harmful in heavy metal element pollution, and the organic pollution is most obvious and most harmful in chemical fertilizers, pesticides, insecticides and herbicides.

The heavy metal element pollution is typified by five heavy metal elements of lead, cadmium, mercury, arsenic and chromium, and the second is a general heavy metal element with certain toxicity, such as: copper, zinc, nickel, cobalt, tin, and the like. The sources of heavy metal elements in soil, besides the inherent heavy metal components of the soil, the enrichment of industrial waste gas, waste water, dust, waste residue, atmosphere, automobile exhaust, household garbage and the like aggravates the content of the heavy metal elements in the soil. Researches show that after the heavy metal elements enter the soil, the heavy metal elements not only have negative influence on the physical property, the biomass, the population structure, the soil enzyme activity and the whole soil ecosystem, but also interfere the development and the metabolic capability of crops, lead the soil to be hardened, acidified and reduced in fertility, lead the quality and the yield of the crops to be reduced, finally accumulate in the human body continuously through a food chain and cause harm to the health of the human body. Meanwhile, in order to offset the reduction of crop quality, yield, disease resistance and the like caused by heavy metal pollution of soil, a grower often further increases the dosage of pesticides, chemical fertilizers and the like, increases organic pollution, causes the superposition of organic and inorganic pollution, and continuously increases the soil deterioration degree of the polluted soil.

Under the realistic situation of severe inorganic heavy metal pollution and organic pollution, China still faces the problem of non-point source pollution that much of the pollution is difficult to control. The non-point source pollution is also called non-point source pollution, has no fixed pollution discharge place, mainly comprises soil silt particles, nutrient substances such as nitrogen and phosphorus, pesticides, various atmospheric particulates and other various components, enters water, soil or atmospheric environment in the modes of surface runoff, soil erosion, farmland drainage and the like, has the characteristics of randomness, universality, hysteresis, fuzziness, latency and the like, and further increases the difficulty of research, treatment and management policy establishment.

Heavy metals and organic pollutants in soil are absorbed by plant roots, accumulated in plants and further reach human bodies through food chains, so that great threat is brought to human health, and the heavy metals and the organic pollutants are absorbed by other parts of the plants through processes of atmospheric circulation, water circulation and the like and then accumulated, and finally enter the human bodies to damage the human health.

Besides the enrichment of harmful components in plants caused by soil pollution, atmospheric dust, waste gas and waste water can also directly contact parts except plant roots, so that the enrichment of the harmful components in the plants is also caused, and the compound pollution can also cause the reduction of the yield and the quality of the plants. The composite pollution is also an important reason for causing environmental non-point source, and agricultural non-point source pollution in China has the characteristics of large area, mainly medium-light pollution, great treatment difficulty and great harm.

In the prior art, a plurality of soil remediation agents exist for soil pollution, and through the passivation and other effects on heavy metal elements in soil, the heavy metal elements are prevented from entering a plant body in an active ionic state or an exchange state, but the heavy metal elements have no effect on preventing other heavy metal elements outside the soil from contacting the plant body from entering the plant body, and the heavy metal elements in the plant body can still continuously enter the soil in transmission, so that even if soil remediation is carried out, heavy metals in the plant body are continuously enriched, and on the other hand, the heavy metal pollution in the soil is difficult to completely eliminate.

In the prior art, a certain research is provided for treating agricultural non-point source pollution, but most of the researches are focused on the preparation and application of preparations for degrading crop residues, the problem of organic pollution of plants can be only partially solved, and the problem of heavy metal pollution of the plants cannot be solved.

For example, in patent application CN1562898A, a method for preparing foliar fertilizer for reducing pesticide residue and promoting crop growth is disclosed, which comprises the following processes: the method comprises the steps of dissolving saccharides including monosaccharide, sugar alcohol and sugar derivatives or oligosaccharide in water, adding rare earth nitrate or rare earth dissolved by dilute acid in advance, adding the rare earth accounting for 0.4-30.8% of the weight of the saccharides, reacting for 24 hours at 10-0 ℃, adjusting the pH value of reaction liquid to 4-7 to obtain liquid foliar fertilizer, further drying and the like to obtain the solid fertilizer, wherein the degradation rate of organophosphorus pesticide can reach more than 80% within a few days of spraying by the inventor, and the yield of crops is increased by 3-20%.

Also disclosed in patent application CN102550553B is a preparation for degrading pesticide residues in plants and a preparation method thereof, wherein the raw materials comprise trichoderma harzianum spore powder, maltose, ferrous sulfate, magnesium sulfate, compound amino acid, boric acid, ethoxy trisiloxane and tween-80 with a concentration of 98%, and the preparation method comprises: adding 5-15 mg of trichoderma harzianum spore powder into 1000ml of water, uniformly mixing, then adding 0.5-1.0 ml of 98% tween-80, then adding 1-5 g of maltose, 0.03-0.07 g of ferrous sulfate, 0.4-0.8 g of magnesium sulfate, 0.4-0.7 g of compound amino acid, 0.02-0.06 g of boric acid and 5ml of ethoxy trisiloxane, and mixing to obtain the preparation.

The preparation can only partially reduce the pollution problem of organic pesticides, and is not helpful for heavy metal pollution of plants and the like.

Disclosure of Invention

The invention aims to provide a blocking agent for plants, which can block the enrichment of harmful components such as heavy metal and the like entering the plants from any way. The invention also aims to provide a barrier agent which can be directly used on soil or/and plant bodies and can effectively reduce heavy metal and organic pollution, and the barrier agent has remarkable effect on repairing non-point source pollution.

The technical scheme of the invention is as follows:

a plant heavy metal blocking agent comprises the following raw materials: selenium methionine, lysine, citric acid and iron salt.

Researches show that heavy metals are generally in two forms of a stable state (solid state) and an exchangeable state in soil and plants, wherein the stable state is hardly adsorbed or accumulated by the plants, the activity is weak, the toxicity is low, and the migration and the movement capabilities are not generated, and the exchangeable state of the heavy metals has the characteristics of super-strong activity, high toxicity, and strong migration and movement capabilities, and the ionic state can be distributed in the soil, the atmosphere and the plants under the action of a liquid phase.

The inventor finds that in the scheme, the selenium methionine, the lysine, the citric acid and the ferric salt have the effects of blocking, degrading and converting heavy metal residues or organic pollutants such as residual pesticides and the like entering the plant body or staying on the surface of the plant under the synergistic effect. The method changes the state of heavy metal in and on the surface of a plant by generating a polymorphic chelating structure, so that the heavy metal is converted into a stable state, and organic pollution components in or on the surface of the plant can be combined in the process, so that the heavy metal is rapidly degraded and converted.

A preferred embodiment of the present invention is: it also comprises one or more of the following raw materials: ammonium thiosulfate, pyroligneous acid, silicate, sodium selenite and wood tar.

The inventor finds that when sodium selenite exists in the scheme, the sodium selenite has the defects of poor water solubility and the like, and needs to be mixed with other components and then subjected to ultrasonic extraction.

It is further preferred that: the blocking agent comprises the following raw materials: selenium methionine, lysine, citric acid, ferric salt, ammonium thiosulfate, wood acetic acid, silicate and wood tar.

Or further preferred thereof: the blocking agent comprises the following raw materials: selenium methionine, lysine, citric acid, ferric salt, ammonium thiosulfate, wood acetic acid, silicate, wood tar and sodium selenite.

In one embodiment of the invention, the silicate is sodium silicate.

In a specific embodiment of the invention, the iron salt is ferrous sulfate.

In a specific embodiment of the invention, the blocking agent comprises, by mass, 3-5 parts of selenium methionine, 1.5-2.0 parts of lysine, 1-3 parts of citric acid, 1-3 parts of iron salt and 100-120 parts of water.

In a specific embodiment of the invention, the blocking agent comprises, by mass, 3-5 parts of selenium methionine, 1.5-2.0 parts of lysine, 1-3 parts of citric acid, 1-3 parts of ferric salt, 3-5 parts of ammonium thiosulfate, 0.1-0.3 part of pyroligneous acid, 0.1-0.3 part of silicate, 0.5-1 part of sodium selenite, 0.1-0.3 part of wood tar and 100-120 parts of water.

The invention also provides a preparation method of the plant barrier agent, which comprises the process of stirring and mixing the raw materials in water completely and uniformly according to the proportion.

Or when the blocking agent contains sodium selenite, the following preparation method is adopted:

(1) adding water into sodium selenite and lysine in a mass ratio of 1:1 to form a mixed solution;

(2) performing ultrasonic extraction on the mixed solution at the temperature of 80-100 ℃ for 1-2 hours to obtain first barrier powder;

(3) and adding the rest raw material components into the first blocking powder in proportion, and uniformly mixing to obtain the plant heavy metal blocking agent.

It is preferable that: the obtained plant heavy metal blocking agent comprises the following raw materials: 3-5 parts of selenium methionine, 1.5-2.0 parts of lysine, 1-3 parts of citric acid, 1-3 parts of ferric salt, 3-5 parts of ammonium thiosulfate, 0.1-0.3 part of pyroligneous acid, 0.1-0.3 part of silicate, 0.5-1 part of sodium selenite, 0.1-0.3 part of wood tar and 100-120 parts of water.

The obtained blocking agent is preferably packaged by a PPC plastic bottle, the packaging bottle is brown to ensure light resistance, and the packaging specification is preferably 120 mL/bottle.

The inventor finds that in practical application, 3 bottles (120 mL/bottle) of the blocking agent can be used for each mu of rice, corn, wheat, vegetables and the like, 60kg of water is added in total, a sprayer, an unmanned aerial vehicle or manual spraying is adopted until the leaves of the plants drip, and the same operation is carried out for every mu of crops at intervals of 3 times in the growth period. Fruit trees, tea leaves and wild tree-like plants can be sprayed by 5 bottles per mu, water is added for 80kg in total, a sprayer, an unmanned aerial vehicle or manual spraying mode can be adopted until the leaf surfaces of the tree-like plants drip, and the tree-like plants are sprayed by 5 times in the growth period per mu at intervals.

The inventor finds that in practical application, the blocking agent of the invention should be stored in a shady place and kept away from light, and the sun exposure is prohibited. The using time period is preferably 6 to 11 am or 4 to 19 pm, and if the rain water is suddenly blown, the complementary spraying is carried out according to the same proportion method after 3 hours.

The invention has the following beneficial effects:

(1) the repairing agent has good blocking, degrading and transforming effects on heavy metals or organic pollutants in a plant body, on the surface of the plant body or in soil and water;

(2) the repairing agent can rapidly and efficiently block the enrichment of heavy metals and organic pollution components in and out of plants;

(3) the repairing agent can be widely applied to repairing of non-point source pollution;

(4) the repairing agent can obviously improve the safety coefficient of crops and block the transmission of harmful ingredients such as heavy metal and the like on a food chain;

(5) after the repairing agent is used, the yield of plants such as grains, vegetables, fruits, medicinal materials and the like can be improved by 10-15%;

(6) after the repairing agent is used, the disease and pest resistance of plants can be enhanced, the immunity of the plants can be enhanced, the protein capacity of the plants can be improved, and the rapid growth and development capacity of the plants can be regulated and controlled;

(7) the repairing agent has the advantages of short period, low repairing cost, economy, rapidness, simple and convenient use and obvious effect.

Detailed Description

The plant heavy metal blocking agent is prepared by the following steps:

firstly, when the blocking agent does not contain sodium selenite, the raw materials of the blocking agent are fully stirred and mixed evenly in water according to a proportion.

Wherein the raw materials comprise selenium methionine, lysine, citric acid and iron salt.

Or preferably: the raw material also comprises one or more of the following components: ammonium thiosulfate, pyroligneous acid, silicate and wood tar.

Secondly, or when the blocking agent contains sodium selenite, adopting the following process:

(1) adding water into sodium selenite powder and lysine powder in a mass ratio of 1:1 to form a mixed solution;

(2) performing ultrasonic extraction on the mixed solution at the temperature of 80-100 ℃ for 1-2 h, and then concentrating and drying to obtain first barrier powder;

(3) and adding the rest raw materials and water into the first blocking powder in proportion, and uniformly mixing to obtain the plant heavy metal blocking agent.

Wherein: the feedstock may include: selenium methionine, lysine, citric acid, iron salt and sodium selenite.

Preferably, the raw material further comprises one or more of ammonium thiosulfate, pyroligneous acid, silicate and wood tar.

In the two preparation processes:

the obtained blocking agent is preferably packaged by a PPC plastic bottle, the packaging bottle is brown to ensure light resistance, and the packaging specification is preferably 120 mL/bottle.

The silicate can be sodium silicate.

The iron salt can be ferrous sulfate.

The blocking agent comprises, by mass, 3-5 parts of selenium methionine, 1.5-2.0 parts of lysine, 1-3 parts of citric acid, 1-3 parts of ferric salt and 100-120 parts of water.

Or the blocking agent comprises, by mass, 3-5 parts of selenium methionine, 1.5-2.0 parts of lysine, 1-3 parts of citric acid, 1-3 parts of ferric salt, 3-5 parts of ammonium thiosulfate, 0.1-0.3 part of pyroligneous acid, 0.1-0.3 part of silicate, 0.5-1 part of sodium selenite, 0.1-0.3 part of wood tar and 100-120 parts of water.

The obtained blocking agent contains selenium methionine, lysine, citric acid, ferric salt, ammonium thiosulfate, silicate and sodium selenite as solids, and wood tar and wood vinegar as liquids, and the raw materials can be purchased from the market.

The water mentioned in the above embodiments is neutral water such as deionized water or distilled water.

On the basis of the above detailed description, the present invention further provides some examples to further illustrate.

Example 1

Uniformly mixing 3-5 parts of selenium methionine, 1.5-2.0 parts of lysine, 1-3 parts of citric acid, 1-3 parts of ferrous sulfate and 100-120 parts of water to obtain the plant heavy metal blocking agent.

Example 2

The plant heavy metal blocking agent is prepared by the following steps:

(1) uniformly mixing sodium selenite powder with the purity of 98% with lysine powder with a small amount of water, wherein the mass ratio of the sodium selenite powder to the lysine powder is 1:1, uniformly stirring the mixed solution, filling the mixed solution into an extraction tank, and adding water with the mass 100 times of the total mass of the solid powder for dissolving to obtain mixed solution;

(2) performing ultrasonic extraction on the mixed solution at 80 ℃ for 2 hours, and concentrating and drying the extracting solution to obtain first blocking powder;

(3) adding the rest raw material components into the first blocking powder in proportion, uniformly mixing, and subpackaging into 120 mL/bottle to obtain the plant heavy metal blocking agent;

wherein all the raw materials comprise:

3 parts of selenium methionine, 1.5 parts of lysine, 1 part of citric acid, 1 part of ferrous sulfate, 3 parts of ammonium thiosulfate, 0.1 part of pyroligneous acid, 0.1 part of sodium silicate, 0.5 part of sodium selenite, 0.1 part of wood tar and 100 parts of water.

Example 3

The plant heavy metal blocking agent is prepared by the following steps:

(1) uniformly mixing sodium selenite powder with the purity of 98% with lysine powder with a small amount of water, wherein the mass ratio of the sodium selenite powder to the lysine powder is 1:1, uniformly stirring the mixed solution, filling the mixed solution into an extraction tank, and adding water with the mass 100 times of the total mass of the solid powder for dissolving to obtain mixed solution;

(2) performing ultrasonic extraction on the mixed solution at 100 ℃ for 1h, and concentrating and drying the extracting solution to obtain first blocking powder;

(3) adding the rest raw material components into the first blocking powder in proportion, uniformly mixing, and subpackaging into 120 mL/bottle to obtain the plant heavy metal blocking agent;

wherein all the raw materials comprise:

5 parts of selenium methionine, 2.0 parts of lysine, 3 parts of citric acid, 3 parts of ferrous sulfate, 5 parts of ammonium thiosulfate, 0.3 part of pyroligneous acid, 0.3 part of sodium silicate, 1 part of sodium selenite, 0.3 part of wood tar and 120 parts of water.

Example 4

The inventor uses the blocking agent prepared in example 2 to carry out pollution restoration treatment on 1 mu of a field in which rice is planted in X plots of a certain village in Chongzhou city, wherein 0.5 mu of a test field and 0.5 mu of a comparison field are used, 1.5 bottles of the blocking agent are used in the test field, the blocking agent is sprayed for 3 times at intervals, 90kg of water is added, and the blocking agent is manually sprayed and compared with the spraying water in the comparison field.

And (3) detecting the heavy metal content of the rice in the mature and harvested test field and the rice in the contrast field according to the following standard detection method:

the detection result (among them) shows:

(1) the detection results of the straws and the rice in the control field are respectively as follows:

A. and (3) detecting the straw:

cadmium content: 0.25 mg/kg;

arsenic content: 0.45 mg/kg;

lead content: 310 mg/kg;

content of chromium: 92 mg/kg;

mercury content: 0.33 mg/kg;

B. and (3) rice detection results:

cadmium content: 0.31 mg/kg;

arsenic content: 0.35 mg/kg;

lead content: 290 mg/kg;

content of chromium: 80 mg/kg;

mercury content: 0.45 mg/kg;

(2) the detection results of the straws and the rice in the test field are respectively as follows:

A. and (3) detecting the straw:

cadmium content: 0.08 mg/kg;

arsenic content: 0.15 mg/kg;

lead content: 105 mg/kg;

content of chromium: 50 mg/kg;

mercury content: 0.15 mg/kg;

B. and (3) rice detection results:

cadmium content: 0.02 mg/kg;

arsenic content: 0.05 mg/kg;

lead content: 80 mg/kg;

content of chromium: 35 mg/kg;

mercury content: 0.07 mg/kg.

The results show that the heavy metal content of the rice straws of the test group is respectively reduced by 0.17mg/kg of cadmium, 0.30mg/kg of arsenic, 205mg/kg of lead, 42mg/kg of chromium and 0.18mg/kg of mercury compared with the heavy metal content of the rice straws of the comparison group; the heavy metal content of the test rice is respectively reduced by 0.29mg/kg of cadmium, 0.30g/kg of arsenic, 90mg/kg of lead, 210mg/kg of chromium and 0.38mg/kg of mercury compared with the heavy metal content of the test rice;

example 5

The inventor uses the blocking agent prepared in the embodiment 3 to carry out remediation and treatment on heavy metal pollution of three vegetables, namely asparagus lettuce, Chinese cabbage and hot pepper, on 1 mu of dry land in a certain village X in double-flow county, and the heavy metal pollution is respectively set as follows:

comparison group: including comparative group a: 0.1 mu of asparagus lettuce; comparative group B: 0.1 mu of Chinese cabbage; comparative group C: 0.1 mu of pepper; in the 3-month growth period, the A, B, C comparison group is subjected to fertilization management according to a conventional planting method;

test groups: included in trial group a: 0.1 mu of asparagus lettuce; test group B: 0.1 mu of Chinese cabbage; test group C: 0.1 mu of pepper;

for the experimental group, the ratio of 0.1 mL: metering 10mL, adding 10kg of water into the blocking agent, and manually spraying by using a sprayer; spraying 1 time every month for 3 times.

After 3 months, each group of vegetables is sampled to detect the heavy metal content, and the results are as follows:

comparative group a: 0.28mg/kg of cadmium, 0.25mg/kg of arsenic, 195mg/kg of lead, 70mg/kg of chromium and 0.32mg/kg of mercury;

comparative group B: 0.27mg/kg of cadmium, 0.32mg/kg of arsenic, 135mg/kg of lead, 75mg/kg of chromium and 0.35mg/kg of mercury;

comparative group C: 0.29mg/kg of cadmium, 0.37mg/kg of arsenic, 125mg/kg of lead, 64mg/kg of chromium and 0.31mg/kg of mercury;

the heavy metal contents of the groups are all higher, and the groups belong to unqualified agricultural products;

test group a: 0.05mg/kg of cadmium, 0.08mg/kg of arsenic, 65mg/kg of lead, 15mg/kg of chromium and 0.10mg/kg of mercury;

test group B: 0.03mg/kg of cadmium, 0.10mg/kg of arsenic, 20mg/kg of lead, 28mg/kg of chromium and 0.07mg/kg of mercury;

test group C: 0.02mg/kg of cadmium, 0.10mg/kg of arsenic, 10mg/kg of lead, 20mg/kg of chromium and 0.10mg/kg of mercury.

Comparing the heavy metal content of the comparative group A with that of the experimental group A: cadmium is reduced by 0.23mg/kg, arsenic is reduced by 0.17mg/kg, lead is reduced by 130mg/kg, chromium is reduced by 55mg/kg, mercury is reduced by 0.22 mg/kg;

comparing the heavy metal content of the comparative group B with that of the test group B: cadmium is reduced by 0.24mg/kg, arsenic is reduced by 0.22mg/kg, lead is reduced by 115mg/kg, chromium is reduced by 47mg/kg, and mercury is reduced by 0.28 mg/kg;

comparing the heavy metal content of the comparative group C with that of the test group C: cadmium decreased by 0.27mg/kg, arsenic decreased by 0.27mg/kg, lead decreased by 115mg/kg, chromium decreased by 44mg/kg, mercury decreased by 0.21 mg/kg.

Example 6

Preparing multiple groups of plant heavy metal blocking agents by the following two processes:

firstly, when the components contain sodium selenite:

(1) uniformly mixing sodium selenite powder with the purity of 98% with lysine powder with a small amount of water, wherein the mass ratio of the sodium selenite powder to the lysine powder is 1:1, uniformly stirring the mixed solution, filling the mixed solution into an extraction tank, and adding water with the mass 100 times of the total mass of the solid powder for dissolving to obtain mixed solution;

(2) performing ultrasonic extraction on the mixed solution at 90 ℃ for 1.5h, and concentrating and drying the extracting solution to obtain first blocking powder;

(3) adding the rest raw material components into the first blocking powder in proportion, uniformly mixing, and subpackaging into 120 mL/bottle to obtain the plant heavy metal blocking agent;

secondly, when the components do not contain sodium selenite:

and (3) adding water into all the raw material components and uniformly mixing to obtain the plant heavy metal blocking agent.

Through the two preparation processes, the plant heavy metal blocking agent with a plurality of formulas is prepared by the following raw materials (in parts by mass):

composition (I)	Formulation 1	Formulation 2	Formulation 3	Formulation 4	Formulation 5	Formulation 6	Formulation 7	Formulation 8	Formulation 9	Formulation 10
											Selenium methionine	20	14	10	7	85	10	9	8	6	5
Lysine	/	6	4	3	6	/	/	2	2	3
											Citric acid	/	/	6	5	5	/	/	/	3	3
Ferrous sulfate	/	/	/	5	2	/	/	/	3	3
											Ammonium thiosulfate	/	/	/	/	2	10	9	8	6	5
Wood vinegar	/	/	/	/	/	/	0.7	0.5	0.3	0.3
											Sodium silicate	/	/	/	/	/	/	0.7	0.5	0.3	0.3
Selenious acidSodium salt	/	/	/	/	/	/	/	1	/	1
											Wood tar	/	/	/	/	/	/	0.7	0.5	0.3	0.3
Water (W)	100	100	100	100	100	100	100	100	100	100

The field to be treated is divided into a test field and a comparison field with the same area, wherein the test field is treated by the prepared barrier agent, and the comparison field is subjected to the same operation process, but only water is sprayed during each spraying.

The treatment process of the test field comprises the following steps:

the prepared heavy metal blocking agents of different groups of plants are mixed according to the weight ratio of 1: diluting with 120 parts of water, spraying every 40 days for 3 times in total, and after 120 days, respectively sampling 1kg of rice to detect the heavy metal content, wherein the detection results are as follows (the heavy metal content unit is mg/kg, the yield unit is kg):

detecting items	Contrast field	Formulation 1	Formulation 2	Formulation 3	Formulation 4	Formulation 5	Formulation 6	Formulation 7	Formulation 8	Formulation 9	Formulation 10
												Cadmium Cd	0.39	0.19	0.18	0.17	0.10	0.08	0.18	0.17	0.18	0.05	0.01
Hg	0.15	0.12	0.10	0.10	0.05	0.03	0.10	0.11	0.10	0.01	0.001
												Lead Pb	0.38	0.20	0.19	0.18	0.12	0.09	0.19	0.16	0.18	0.07	0.005
Arsenic As	0.21	0.18	0.15	0.14	0.10	0.09	0.17	0.16	0.16	0.02	0.003
												Chromium Cr	0.37	0.20	0.20	0.18	0.13	0.12	0.18	0.17	0.15	0.11	0.05
Yield of the product	155	158	158.5	158.8	162	161.5	159	158	160	166	168.5

From the comparison, the formulas 1-10 have certain heavy metal barrier agent yield increasing effect, wherein the formula 10 is the most obvious in barrier effect and yield increasing effect, and the formulas 4, 5, 9 and 10 containing selenium methionine, lysine, citric acid and ferrous sulfate are adopted.

It is to be understood that the above-described embodiments are merely illustrative of some of the presently preferred embodiments of the invention, and that the present invention is not limited to the processes, operations, and parameters provided by the above-described embodiments.

Claims (5)

1. A plant heavy metal blocking agent is characterized in that: the blocking agent comprises the following raw materials: 6 parts of selenium methionine, 2 parts of lysine, 3 parts of citric acid, 3 parts of ferric salt, 6 parts of ammonium thiosulfate, 0.3 part of wood vinegar, 0.3 part of silicate and 0.3 part of wood tar.

2. A plant heavy metal blocking agent is characterized in that: the blocking agent comprises the following raw materials: the feed additive comprises 3-5 parts of selenium methionine, 1.5-2.0 parts of lysine, 1-3 parts of citric acid, 1-3 parts of ferric salt, 3-5 parts of ammonium thiosulfate, 0.1-0.3 part of pyroligneous acid, 0.1-0.3 part of silicate, 0.5-1 part of sodium selenite, 0.1-0.3 part of wood tar and 100-120 parts of water.

3. The plant heavy metal blocking agent according to claim 1 or 2, characterized in that: the silicate is sodium silicate.

4. The plant heavy metal blocking agent according to claim 1 or 2, characterized in that: the iron salt is ferrous sulfate.

5. The method for preparing a plant heavy metal blocking agent according to claim 2, wherein: the method comprises the following steps:

(1) adding water into sodium selenite and lysine in a mass ratio of 1:1 to form a mixed solution;

(2) performing ultrasonic extraction on the mixed solution at the temperature of 80-100 ℃ for 1-2 hours to obtain first barrier powder;

(3) and adding the rest raw material components into the first blocking powder in proportion, and uniformly mixing to obtain the plant heavy metal blocking agent.