Thickening suspending agent containing modified palygorskite and its use

Abstract

The application discloses thickening suspending agent containing modified palygorskite and application thereof, and belongs to the technical field of thickening suspending agent, wherein the content of impurities on the surface of palygorskite is reduced, the surface area and porous property are increased after acidification treatment, the loading rate of zero-valent iron can be improved, the zero-valent iron is uniformly loaded in the tubular channel or surface of palygorskite in the form of nanoparticles, the surface roughness of the composite powder is increased, stronger steric hindrance can be formed around the pesticide particles, the pesticide particles are prevented from gathering and becoming larger due to collision, thereby the settlement is reduced, the good suspending property and dispersing property are achieved, and the loading of zero-valent iron can endow the thickening suspending agent with the ability of chelating heavy metals; through twice intercalation treatment, the modified zero-valent iron composite palygorskite powder can be uniformly loaded between the layers of graphene oxide, the dispersion of palygorskite can be assisted by graphene oxide to avoid agglomeration, and the presence of graphene oxide can increase the thermal stability of the thickening suspending agent.

Description

Technical Field

[0001] This invention belongs to the field of thickening and suspending agent technology, specifically a thickening and suspending agent containing modified attapulgite and its application. Background Technology

[0002] Attapulgite, as a natural one-dimensional nanomaterial, is inexpensive and abundant, making it a promising reinforcing agent capable of improving the mechanical properties of polymers. However, attapulgite itself is prone to aggregation and has poor compatibility with polymer matrices. Currently, multidimensional nanocomposites prepared from nanomaterials of different dimensions are becoming a research hotspot. By utilizing the differences in aggregation modes of nanomaterials of different dimensions to assemble them into specific structures, these differences can be used to inhibit each other's aggregation, thereby improving compatibility with polymers. At the same time, such multidimensional nanocomposites combine the advantages of both materials.

[0003] Chinese patent CN116035000A discloses a stable fluorinated amine suspension agent and its preparation method. In this method, modified attapulgite is prepared. After acidification and sodium treatment, the attapulgite is subjected to high-temperature treatment to remove some soluble impurities and bound water, thereby increasing its surface area. At high temperature, sodium ions react with the acidic active sites in the attapulgite, thereby improving the acid value of the attapulgite and increasing its hydrophilic and oleophilic properties. Then, the attapulgite is further treated with hexadecyltrimethylammonium bromide, which allows long-chain organic carbon chains to enter the interlayer gaps generated by the attapulgite, further improving the suspension performance.

[0004] However, attapulgite, as a "nanorod" with a diameter of 10-30 nm and a length of 1-2 μm, tends to entangle into aggregates due to its high surface energy. In the above-mentioned scheme, attapulgite is still prone to agglomeration, and when it is compounded with different types of wetting and penetrating agents, defoamers, antifreeze agents and thixotropic agents, it cannot achieve the best effect. Summary of the Invention

[0005] The purpose of this invention is to provide a thickening suspending agent containing modified attapulgite and its application. After acidification treatment, the impurity content on the surface of attapulgite is reduced, and the surface area and porosity are increased, which can improve the loading rate of zero-valent iron. Zero-valent iron is uniformly loaded as nanoparticles on the tubular channels or surface of attapulgite, further increasing the surface roughness of the composite powder. This can form stronger steric hindrance around pesticide particles, preventing pesticide particles from agglomerating and growing due to collision, thereby reducing sedimentation and giving it good suspension and dispersibility. Furthermore, the loading of zero-valent iron can endow the thickening suspending agent containing modified attapulgite with the ability to chelate heavy metals, avoiding the harm of heavy metals in pesticides to crops.

[0006] The objective of this invention can be achieved through the following technical solutions:

[0007] A thickening suspending agent containing modified attapulgite is prepared by the following steps:

[0008] Step 1: Using the liquid-phase reduction method, acidified attapulgite powder is used as a carrier. Iron ions are reduced on the surface of the acidified attapulgite powder by sodium borohydride to obtain zero-valent iron composite attapulgite powder.

[0009] Step 2: Treat the zero-valent iron composite attapulgite powder with γ-aminopropyltriethoxysilane to obtain modified zero-valent iron composite attapulgite powder.

[0010] Step 3: Intercalate graphene oxide with sodium dodecyl sulfonate, and then combine the resulting graphene oxide sheets with modified zero-valent iron composite attapulgite powder through electrostatic assembly to obtain modified attapulgite composite powder.

[0011] Step 4: Using fluorinated amine, modified attapulgite composite powder, sodium diisooctyl succinate sulfonate, silicone defoamer, polyethylene glycol antifreeze, xanthan gum, and deionized water as raw materials, the mixture is subjected to high-speed shearing and grinding to obtain a thickening suspending agent containing modified attapulgite.

[0012] Furthermore, the acidified attapulgite powder is obtained by acidifying attapulgite powder with an average particle size of 5 μm with hydrochloric acid.

[0013] Furthermore, the specific preparation steps for zero-valent iron composite attapulgite powder are as follows:

[0014] Ferric sulfate heptahydrate, acidified attapulgite powder, and deionized water were added to a reaction vessel and stirred for 40-50 minutes at 20-25℃ and 500-600 rpm. Stirring was continued for 2-3 hours under a nitrogen atmosphere. Then anhydrous ethanol was added and stirring was continued for 30-40 minutes. Next, a 1 mol / L sodium borohydride solution was added and stirring was continued for 30-40 minutes. The mixture was centrifuged at 5000-6000 rpm for 5-6 minutes. The product was washed 2-4 times with deionized water and anhydrous ethanol, respectively, and then vacuum dried at 60-80℃ for 1-2 hours to obtain zero-valent iron composite attapulgite powder.

[0015] Furthermore, the ratio of ferric sulfate heptahydrate, acidified attapulgite powder, deionized water, anhydrous ethanol, and sodium borohydride solution is 40-50g: 40-42g: 500-520mL: 120-140mL: 150-170mL.

[0016] Furthermore, the specific preparation steps for modified zero-valent iron composite attapulgite powder are as follows:

[0017] Ethanol, zero-valent iron composite attapulgite powder, and γ-aminopropyltriethoxysilane were added to a reaction vessel and stirred for 40-50 minutes at 20-25℃ and 500-600 r / min. The mixture was then heated to 80-90℃ and stirred for another 3-4 hours. The mixture was filtered, and the precipitate was collected. The precipitate was washed 2-4 times with deionized water and anhydrous ethanol, respectively, and then dried under vacuum at 60-80℃ for 1-2 hours to obtain modified zero-valent iron composite attapulgite powder.

[0018] Furthermore, the ratio of ethanol, zero-valent iron composite attapulgite powder, and γ-aminopropyltriethoxysilane is 1.5-1.7L: 30-35g: 10-20g.

[0019] Furthermore, the specific preparation steps of the modified attapulgite composite powder are as follows:

[0020] Graphene oxide and deionized water were added to a reaction vessel and stirred for 40-50 min at 20-25℃ and 500-600 r / min. Sodium dodecyl sulfonate was then added, and stirring was continued for 1-2 h. The mixture was then ultrasonically dispersed for 40-60 min. Modified zero-valent iron composite attapulgite powder and deionized water were then added, and stirring was continued for 2-3 h. The mixture was allowed to stand for 12-14 h, filtered, and the precipitate was collected. The precipitate was washed 2-4 times with deionized water and anhydrous ethanol, respectively, and then vacuum dried at 60-80℃ for 1-2 h to obtain modified attapulgite composite powder.

[0021] Furthermore, the ratio of graphene oxide, deionized water, sodium dodecyl sulfonate, modified zero-valent iron composite attapulgite powder, and deionized water is 0.4-0.8g: 2-3L: 5-10g: 20-25g: 1.8-2L.

[0022] Furthermore, the ratio of the following components is as follows: fluorinated amine, modified attapulgite composite powder, sodium diisooctyl succinate sulfonate, organosilicon defoamer, polyethylene glycol, xanthan gum, and deionized water is 30-40g: 0.5-0.7g: 9-10g: 0.5-0.7g: 1-2g: 0.1-0.2g: 60-70g.

[0023] The beneficial effects of this invention are:

[0024] 1. The thickening and suspending agent containing modified attapulgite prepared by this invention reduces the impurity content on the surface of attapulgite after acidification treatment, and increases its surface area and porosity, thereby improving the loading rate of zero-valent iron. Zero-valent iron is uniformly loaded as nanoparticles onto the tubular channels or surface of attapulgite, further increasing the surface roughness of the composite powder. This creates stronger steric hindrance around pesticide particles, preventing them from agglomerating and growing due to collisions, thus reducing sedimentation and giving it good suspension and dispersibility. Furthermore, the loading of zero-valent iron endows the thickening and suspending agent containing modified attapulgite with the ability to chelate heavy metals, preventing heavy metals in pesticides from harming crops.

[0025] 2. The modified attapulgite composite powder of the present invention is prepared by modifying zero-valent iron composite attapulgite powder with γ-aminopropyltriethoxysilane to carry positively charged amino groups on its surface. Then, graphene oxide is intercalated with sodium dodecyl sulfonate, and then electrostatic assembly is used to intercalate the modified zero-valent iron composite attapulgite powder with graphene oxide. Through two intercalation treatments, the modified zero-valent iron composite attapulgite powder can be uniformly loaded between the graphene oxide layers. Graphene oxide can assist in the dispersion of attapulgite and prevent agglomeration. Furthermore, the presence of graphene oxide can increase the thermal stability of the thickening suspending agent.

[0026] 3. This invention utilizes electrostatic assembly to intercalate modified zero-valent iron composite attapulgite powder into graphene oxide. Graphene oxide itself is negatively charged in aqueous solution due to its rich surface content of carboxyl and hydroxyl oxygen-containing functional groups. When sodium dodecyl sulfonate is intercalated into the interlayer of graphene oxide, the hydrophilic groups of sodium dodecyl sulfonate face outwards, further enhancing the overall electronegativity. The carboxyl groups in graphene oxide are edge carboxyl groups. After attapulgite is modified with silane, it carries amino groups. The amino groups combine with the carboxyl groups of graphene oxide. However, the spatial position of the edge carboxyl groups prevents some attapulgite from effectively entering the interlayer. After surfactant intercalation, on the one hand, the interlayer spacing increases, and on the other hand, the increased electronegativity of the sulfonic acid groups and the electrostatic attraction of the positively charged amino groups in the attapulgite promote more attapulgite intercalation into the interlayer of graphene oxide. Detailed Implementation

[0027] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0028] Example 1: A thickening suspending agent containing modified attapulgite, prepared by the following steps:

[0029] S1: Under a nitrogen atmosphere, attapulgite was ground and pulverized to obtain attapulgite powder with an average particle size of 5 μm. 60 g of attapulgite powder and 600 g of deionized water were added to a reaction vessel and stirred for 50 min at 25 °C and 600 r / min. Then, 12 mL of 1 mol / L hydrochloric acid solution was added to adjust the pH to 4. The mixture was heated to 70 °C and stirred for another 3 h. The mixture was filtered, and the precipitate was collected. The precipitate was washed four times with deionized water and four times with anhydrous ethanol, and then dried under vacuum at 80 °C for 2 h to obtain acidified attapulgite powder.

[0030] S2: Add 50g of ferric sulfate heptahydrate, 42g of acidified attapulgite powder, and 520mL of deionized water to a reaction vessel. Stir at 25℃ and 600r / min for 50min. Continue stirring for 3h under a nitrogen atmosphere. Then add 140mL of anhydrous ethanol and stir for 40min. Then add 170mL of 1mol / L sodium borohydride solution and stir for 40min. Centrifuge at 6000r / min for 6min. Wash the product four times with deionized water and anhydrous ethanol, respectively. Dry under vacuum at 80℃ for 2h to obtain zero-valent iron composite attapulgite powder.

[0031] S3: Add 1.7L of ethanol, 35g of zero-valent iron composite attapulgite powder and 20g of γ-aminopropyltriethoxysilane to a reaction vessel, stir for 50min at 25℃ and 600r / min, heat to 90℃, continue stirring for 4h, filter, collect the precipitate, wash the precipitate 4 times with deionized water and anhydrous ethanol respectively, and vacuum dry at 80℃ for 2h to obtain modified zero-valent iron composite attapulgite powder.

[0032] S4: Add 0.8g of graphene oxide and 3L of deionized water to the reactor and stir for 50min at 25℃ and 600r / min. Then add 10g of sodium dodecyl sulfonate and continue stirring for 2h. Ultrasonically disperse for 60min, then add 25g of modified zero-valent iron composite attapulgite powder and 2L of deionized water. Continue stirring for 3h, let stand for 14h, filter, collect the precipitate, wash the precipitate four times with deionized water and anhydrous ethanol respectively, and vacuum dry at 80℃ for 2h to obtain modified attapulgite composite powder.

[0033] S5: Add 40g of fluopyram, 0.7g of modified attapulgite composite powder, 10g of sodium diisooctyl succinate sulfonate, 0.7g of organosilicon defoamer, 2g of polyethylene glycol antifreeze and 0.2g of xanthan gum to 70g of deionized water, and disperse at a high speed of 2200r / min for 30min. Then grind until the solid particle size in the mixture is 20μm to obtain a thickening suspending agent containing modified attapulgite.

[0034] Example 2: The thickening suspending agent containing modified attapulgite provided in this example differs from Example 1 in that the ratio of attapulgite powder, deionized water and hydrochloric acid solution in step S1 is 55g:550g:11mL.

[0035] Example 3: The thickening suspending agent containing modified attapulgite provided in this example differs from that in Example 1 in that the ratio of ferric sulfate heptahydrate, acidified attapulgite powder, deionized water, anhydrous ethanol and sodium borohydride solution in step S2 is 45g:41g:510mL:130mL:160mL.

[0036] Example 4: The thickening suspending agent containing modified attapulgite provided in this example differs from that in Example 1 in that the ratio of ethanol, zero-valent iron composite attapulgite powder and γ-aminopropyltriethoxysilane in step S3 is 1.6L:33g:15g.

[0037] Example 5: The thickening suspending agent containing modified attapulgite provided in this example differs from that in Example 1 in that the ratio of graphene oxide, deionized water, sodium dodecyl sulfonate, modified zero-valent iron composite attapulgite powder and deionized water in step S4 is 3g:2.3L:8g:23g:1.9L.

[0038] Example 6: This example provides a thickening and suspending agent containing modified attapulgite, which differs from Example 1 in that the ratio of the following in step S5 is 35g:0.6g:9.5g:0.6g:1.2g:0.15g:65g:fluorine amine, modified attapulgite composite powder, sodium diisooctyl succinate sulfonate, silicone defoamer, polyethylene glycol, xanthan gum, and deionized water.

[0039] Comparative Example 1: Based on Example 1, the acidified attapulgite powder in step S2 was replaced with the attapulgite powder in step S1, while the other steps remained unchanged, to prepare a thickening suspending agent containing modified attapulgite.

[0040] Comparative Example 2: Based on Example 1, the zero-valent iron composite attapulgite powder in step S3 was replaced with the acidified attapulgite powder in step S1, while the other steps remained unchanged, to prepare a thickening suspending agent containing modified attapulgite.

[0041] Comparative Example 3: Based on Example 1, sodium dodecyl sulfonate in step S4 was omitted, while the other steps remained unchanged, to prepare a thickening suspending agent containing modified attapulgite.

[0042] The performance of the thickening suspensions containing modified attapulgite prepared in Examples 1-6 and Comparative Examples 1-3 was tested. The dispersibility of the thickening suspensions containing modified attapulgite was tested according to the FAO standard CIPAC method. The thermal stability of the thickening suspensions containing modified attapulgite after 14 days of thermal storage at 54°C was tested according to GB / T 19136-2021. The change in the content of the thickening suspensions containing modified attapulgite before and after thermal storage was determined by HPLC, and the decomposition rate was calculated. The decomposition rate result was used as the test standard. According to GB / T For the test according to 14825-2023, hard water with a hardness of 342 mg / L, a calcium-magnesium ion molar ratio of 4:1, and a pH of 7.0 was used. The thickening suspending agent containing modified attapulgite was mixed with hard water at a mass ratio of 1:10 to form a suspension. The suspension was allowed to stand in a graduated cylinder for 30 minutes. The upper 9 / 10 of the suspension was removed, and the mass of the effective components in the bottom 1 / 10 of the suspension was determined by the effective component method. The suspension rate was then calculated.

[0043] Take dried sample soil, pass it through a 9.5mm sieve, and mix 2g of 200mg / L copper nitrate trihydrate, 80g of deionized water, and 200g of sample soil in a mortar mixer for 10 minutes to obtain the sample soil. Mix the thickening suspending agent containing modified attapulgite with the sample soil at a weight ratio of 24:100, mix in a mortar mixer for 10 minutes, and cure in a sealed container for 28 days. Leach heavy metals using the SW-846 TestMethod 1315 method, and then test the copper concentration using inductively coupled plasma atomic emission spectrometry (ICP). Calculate the adsorption rate. The results are shown in Table 1.

[0044] Table 1. Performance Test Table of Thickening Suspension Agents Containing Modified Attapulgite

[0045] project Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Comparative Example 1 Comparative Example 2 Comparative Example 3 Dispersion excellent excellent excellent excellent excellent excellent Difference good good Suspension rate (%) 96 95 95 94 94 94 75 83 81 Thermal storage stability (%) 1.2 1.4 1.4 1.3 1.3 1.3 5.2 2.8 2.6 Adsorption rate (%) 91.52 91.35 91.31 92.56 92.68 92.49 81.57 71.62 85.63

[0046] As can be seen from Table 1, the dispersibility, suspension rate, and cadmium removal rate of the thickening suspending agents containing modified attapulgite prepared in Examples 1-6 are significantly better than those in the comparative examples. This indicates that the thickening suspending agents containing modified attapulgite prepared in this invention have good suspension, dispersibility and thermal stability, and can chelate heavy metals to avoid the harm of heavy metals in pesticides to crops.

[0047] In Comparative Example 1, acidified attapulgite powder was replaced with unacidified attapulgite powder. The unacidified attapulgite had more impurities on its surface, a smaller specific surface area, and fewer active sites, making it unable to effectively bind iron ions through adsorption / coordination. This resulted in a significant reduction in the zero-valent iron loading rate. Furthermore, the unbound zero-valent iron easily agglomerated into large particles, causing pesticide particles in the suspension to easily collide and aggregate, significantly reducing suspension stability. During storage, it was prone to sedimentation and stratification. The insufficient zero-valent iron loading meant that the suspension could not effectively adsorb heavy metals in pesticides, and the subsequent silane modification and graphene oxide composite were affected. The unacidified attapulgite had fewer active sites on its surface, and silane molecules were also difficult to stably bind to the carrier surface, resulting in insufficient amino introduction. Consequently, the electrostatic assembly effect of graphene oxide was weakened, and graphene oxide was prone to agglomeration.

[0048] In Comparative Example 2, the zero-valent iron composite attapulgite powder was replaced with the acidified attapulgite powder in step S1. The lack of zero-valent iron load resulted in the suspension being unable to effectively adsorb heavy metals in pesticides. Without zero-valent iron, the surface structure of the acidified attapulgite alone weakened the anti-aggregation constraint on pesticide particles, making the suspension prone to stratification and reducing its dispersibility. The acidified attapulgite alone relied on hydroxyl groups to bind silanes, resulting in low modification efficiency and insufficient amino group introduction. Graphene oxide could not be uniformly composited on the carrier surface and instead agglomerated, losing both its auxiliary dispersing effect and its ability to enhance thermal stability. Ultimately, the thermal stability of the suspension decreased significantly.

[0049] In Comparative Example 3, sodium dodecyl sulfonate was omitted. Due to van der Waals forces, the graphene oxide sheets tended to stack and agglomerate tightly. Without sodium dodecyl sulfonate, the interlayer spacing of the graphene oxide was extremely small, which reduced the efficiency of the modified zero-valent iron composite attapulgite in inserting into the interlayer. It could only adhere to the surface of the graphene oxide, resulting in a decrease in the dispersibility and suspension stability of the suspending agent.

[0050] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the invention.

Claims

1. A thickening and suspending agent containing modified attapulgite, characterized in that, Prepared by the following steps: Step 1: Using the liquid-phase reduction method, acidified attapulgite powder is used as a carrier. Iron ions are reduced on the surface of acidified attapulgite powder by sodium borohydride to obtain zero-valent iron composite attapulgite powder. Step 2: The zero-valent iron composite attapulgite powder is treated with γ-aminopropyltriethoxysilane to obtain modified zero-valent iron composite attapulgite powder. Step 3: Intercalate graphene oxide with sodium dodecyl sulfonate, and then combine the obtained graphene oxide sheets with modified zero-valent iron composite attapulgite powder through electrostatic assembly to obtain modified attapulgite composite powder. Step 4: Using fluorinated amine, modified attapulgite composite powder, sodium diisooctyl succinate sulfonate, silicone defoamer, polyethylene glycol antifreeze, xanthan gum and deionized water as raw materials, high-speed shearing and grinding are carried out to obtain a thickening suspending agent containing modified attapulgite. The specific preparation steps for the zero-valent iron composite attapulgite powder are as follows: Ferric sulfate heptahydrate, acidified attapulgite powder, and deionized water were added to a reaction vessel and stirred for 40-50 minutes at 20-25℃ and 500-600 r / min. Stirring was continued for 2-3 hours under a nitrogen atmosphere. Then anhydrous ethanol was added and stirring was continued for 30-40 minutes. Then a 1 mol / L sodium borohydride solution was added and stirring was continued for 30-40 minutes. The mixture was centrifuged at 5000-6000 r / min for 5-6 minutes. The product was washed 2-4 times with deionized water and anhydrous ethanol, respectively, and then vacuum dried at 60-80℃ for 1-2 hours to obtain zero-valent iron composite attapulgite powder. The specific preparation steps for the modified zero-valent iron composite attapulgite powder are as follows: Ethanol, zero-valent iron composite attapulgite powder, and γ-aminopropyltriethoxysilane were added to a reaction vessel and stirred for 40-50 min at 20-25℃ and 500-600 r / min. The mixture was then heated to 80-90℃ and stirred for 3-4 h. After filtration, the precipitate was collected and washed 2-4 times with deionized water and anhydrous ethanol, respectively. The precipitate was then vacuum dried at 60-80℃ for 1-2 h to obtain modified zero-valent iron composite attapulgite powder. The specific preparation steps of the modified attapulgite composite powder are as follows: Graphene oxide and deionized water were added to a reaction vessel and stirred for 40-50 min at 20-25℃ and 500-600 r / min. Sodium dodecyl sulfonate was then added, and stirring was continued for 1-2 h. The mixture was then ultrasonically dispersed for 40-60 min. Modified zero-valent iron composite attapulgite powder and deionized water were then added, and stirring was continued for 2-3 h. The mixture was allowed to stand for 12-14 h, filtered, and the precipitate was collected. The precipitate was washed 2-4 times with deionized water and anhydrous ethanol, respectively, and then vacuum dried at 60-80℃ for 1-2 h to obtain modified attapulgite composite powder.

2. The thickening and suspending agent containing modified attapulgite as described in claim 1, characterized in that, The ratio of the following components is: fluorinated amine, modified attapulgite composite powder, sodium diisooctyl succinate sulfonate, silicone defoamer, polyethylene glycol, xanthan gum, and deionized water: 30-40g: 0.5-0.7g: 9-10g: 0.5-0.7g: 1-2g: 0.1-0.2g: 60-70g.

3. The thickening and suspending agent containing modified attapulgite clay according to claim 1, characterized in that, The acidified attapulgite powder is obtained by acidifying attapulgite powder with an average particle size of 5 μm with hydrochloric acid.

4. The thickening and suspending agent containing modified attapulgite as described in claim 1, characterized in that, The ratio of the amounts of ferric sulfate heptahydrate, acidified attapulgite powder, deionized water, anhydrous ethanol, and sodium borohydride solution is 40-50g: 40-42g: 500-520mL: 120-140mL: 150-170mL.

5. A thickening suspending agent containing modified attapulgite as described in claim 1, characterized in that, The ratio of ethanol, zero-valent iron composite attapulgite powder, and γ-aminopropyltriethoxysilane is 1.5-1.7L: 30-35g: 10-20g.

6. The thickening and suspending agent containing modified attapulgite as described in claim 1, characterized in that, The ratio of graphene oxide, deionized water, sodium dodecyl sulfonate, modified zero-valent iron composite attapulgite powder, and deionized water is 0.4-0.8g: 2-3L: 5-10g: 20-25g: 1.8-2L.