Application of water-soluble rosinyl tricarboxylate in precipitation removal and enrichment recovery of heavy metal ions

Abstract

The invention discloses an application of water-soluble rosinyl tricarboxylate in precipitation removal and enrichment recovery of heavy metal ions. Natural rosin reacts with fumaric acid to obtain fumaric acid, the fumaric acid is alkalized to obtain rosinyl tricarboxylate, the rosinyl tricarboxylate and heavy metal ions such as copper, cadmium and lead in water can easily form solid precipitates at room temperature, and the heavy metal ions in the water can be adsorbed, removed or recycled after simple filtration. The product has a good effect of removing heavy metal ions in water, the removal efficiency of copper, cadmium and lead can reach 99.9% or above, and the residual quantity of the heavy metal ions in the treated water meets the standard requirement of drinking water; the product disclosed by the invention can also be used for recycling rare metals in industrial wastewater. The product can be regenerated and reused, has the characteristics of environmental protection, low cost, high adsorption efficiency, easiness in desorption, simplicity and convenience in regeneration, wide adaptability and the like when being used for treating heavy metal ion pollution in water, and has excellent application prospects and social and economic benefits when being used for treating industrial and mining enterprise wastewater containing metal ions.

Description

Technical Field

[0001] The invention relates to the technical field of sewage treatment, and in particular to application of a water-soluble rosin-based tricarboxylate in precipitation removal and enrichment recovery of heavy metal ions. Background Art

[0002] Water pollution has become one of the major environmental issues facing the world. The causes of water pollution are numerous, covering industries, agriculture, urban sewage and land development. Industrial activities are one of the main root causes of water pollution. These include harmful chemicals, heavy metals and organic pollutants. The continuous improvement of water pollution is crucial to protecting human health.

[0003] In recent years, affected by urbanization, the problem of environmental pollution in mining areas has become increasingly prominent, among which heavy metal pollution in mining areas is the most serious, such as nickel ions, lead ions, copper ions, manganese ions, cadmium ions and other heavy metals. Heavy metals cannot be metabolized and decomposed in the human body. They are a kind of pollutants that cannot be naturally decomposed in water, which has an adverse effect on human health and the natural environment. Since heavy metal ions can attach to proteins, nucleic acids and small metabolites in organisms, they can be precipitated in bones, fat, muscles and joints, causing a series of diseases and functional difficulties of organs. Some heavy metals have the triple effects of mutagenicity, carcinogenicity and teratogenicity. It will cause serious harm to the health of humans and animals, including organ atrophy, cancer, nervous system disorders, body defense system disorders and life-threatening diseases. On the other hand, many heavy metal elements have their own unique density, strength, electromagnetic and chemical properties, and are used in many fields, such as light industry and machinery, petroleum and chemical industry, electronics and electricity, energy and safety, medical and equipment, weapons and ammunition, aviation and aerospace, etc. For example, nickel has good corrosion resistance, high temperature resistance, and rust resistance, so it is widely used in steel fields such as stainless steel and alloy steel; non-ferrous metal copper has excellent electrical conductivity, thermal conductivity, ductility, corrosion resistance, wear resistance and other aspects, and is widely used in many fields such as electronics and electricity, energy and petrochemicals, light industry and chemical industry, machinery and metallurgy, transportation and transportation, and other emerging industries; cadmium is used in battery materials, electroplating, plastics, non-ferrous alloys, photovoltaic equipment, etc.; most of manganese is used in the steel industry, and a small part is used in non-ferrous metallurgy, chemical industry, electronics, batteries, agriculture, etc.; lead has good ductility and corrosion resistance, and it is easy to make alloys with other metals with excellent performance. Lead in the form of single substance, alloy or compound is widely used in batteries, cable sheaths, machinery and shipbuilding, light industry, radiation protection and other industries. Therefore, the recycling of heavy metals and rare metals in industrial wastewater or waste is also an urgent problem to be solved. However, whether it is the removal of heavy metal pollution in water or the recovery and utilization of precious metals from industrial wastewater, although the purposes are different, the treatment process and the final effect are the same. Various measures are taken to enrich the metal ions in the water and separate them from the water. So they are two sides of the same coin. Reagents that can adsorb and remove metal pollution in water can generally also be used to recover precious and rare metals in water.

[0004] There are many effective methods to remove heavy metals from water. Conventional methods include extraction, chemical precipitation, membrane filtration and adsorption. Since adsorption has the characteristics of a wide pH adaptability range, easy separation and simple operation, it has become one of the commonly used methods for water pollution treatment. The adsorption efficiency depends on the adsorbent material, so the current research hotspot in related fields is to seek low-cost, green and efficient adsorption materials. More and more materials have been found to be used as adsorbents, indicating that there is a lot of room for the development of adsorbent types. In particular, adsorbents that are easy to prepare, simple to operate and low in cost are considered to be an effective and economical material, leading the research trend of removing heavy metals from wastewater. Common adsorption materials include inorganic adsorption materials and natural or synthetic polymer adsorption materials. These solid adsorption materials involve multi-step preparation reactions from monomer raw materials to polymer adsorption material synthesis. In addition, the pore and hole structure of the polymer material must be adjusted, and there are many constraints on the generation. In addition, the metal ions in the water must first diffuse to the outer surface of the polymer adsorbent, and then penetrate into the inner surface of the solid pores through internal diffusion. The mass transfer efficiency is generally low, and the time required to fully take effect is relatively long, which sometimes cannot meet actual needs. Inorganic small molecules such as sodium sulfide can directly form compounds with metal ions and precipitate, which can quickly reduce the metal ion content in water, but are difficult to reuse. Many organic small molecules such as ethylenediaminetetraacetic acid and its sodium salt are also easy to coordinate with metal ions, with high mass transfer efficiency, but rarely form precipitates. Organic solvents must be selected for complex operations such as extraction and separation to separate them from water. The rosin-based tricarboxylate heavy metal ion precipitant provided by the present invention is a renewable natural resin acid derivative with moderate molecular weight, and the raw materials are cheap and easily available, the preparation method is simple, the product stability is good, and it can also be easily regenerated and used repeatedly. The key is that the reagent does not need to go through surface diffusion and internal diffusion processes when adsorbing, separating or enriching metal ions in water, and the mass transfer efficiency is high. It has the characteristics of easy separation and regeneration of polymer adsorbents and high efficiency of small molecule reagents. Summary of the invention

[0005] The present invention provides an application of a water-soluble rosin-based tricarboxylate in the precipitation removal and enrichment recovery of heavy metal ions. The present invention uses fumaric acid (fumaric acid) and rosin as raw materials to carry out a simple DA addition reaction to obtain fumaric rosin, and then adds potassium hydroxide and anhydrous ethanol to the dissolved fumaric rosin to prepare a rosin-based tricarboxylate. The reagent can be used to adsorb and remove metal ions (nickel ions, lead ions, copper ions, manganese ions, and cadmium ions) in water to meet drinking water standards. The application of a water-soluble rosin-based tricarboxylate in the precipitation removal and enrichment recovery of heavy metal ions provided by the present invention has the advantages of low generation and operation cost, simple, safe and convenient operation, high adsorption efficiency, etc., and has excellent application prospects and social and economic benefits in treating industrial and mining wastewater.

[0006] The technical solution of the present invention is as follows:

[0007] A water-soluble rosin-based tricarboxylate heavy metal ion precipitant, the structural formula of which is as follows:

[0008]

[0009] The present invention provides an application of a water-soluble rosin-based tricarboxylate in the precipitation removal and enrichment recovery of heavy metal ions. The specific method comprises the following steps:

[0010] Step 1: Add 0.1 g / L to 0.8 g / L of rosin-based tricarboxylate precipitant into 25 ml of metal ion solutions with concentrations of 5 mg / L, 10 mg / L, and 20 mg / L, respectively.

[0011] Step 2: Place the sample from step 1 in a constant temperature shaker and oscillate at 298K and 150r / min for 24 hours to ensure adsorption equilibrium.

[0012] Step 3: After the sample that has reached adsorption equilibrium in step 2 is passed through a microfiltration membrane, the metal ion content in the solution is determined by atomic absorption.

[0013] The rosin-based tricarboxylate precipitant is used to adsorb heavy metal ions such as nickel ions, lead ions, copper ions, manganese ions and cadmium ions.

[0014] The present invention has the following advantages:

[0015] 1. Rosin-based tricarboxylate precipitant has high adsorption efficiency and no toxic residue, and can adsorb various metal ions in water more safely and efficiently.

[0016] 2 It has the advantages of wide pH range, strong metal binding ability, easy operation, low production cost, and green environmental protection. It has excellent application prospects and social and economic benefits in treating industrial and mining wastewater. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is the infrared spectrum of rosin-based tricarboxylate before and after adsorption.

[0018] Figure 2 , Figure 3 These are the adsorption amounts and removal rates obtained at different addition amounts of rosin-based tricarboxylate when the initial metal ion concentration in Example 1 is 5 mg / L.

[0019] Figure 4 , Figure 5 These are the adsorption amounts and removal rates obtained at different addition amounts of rosin-based tricarboxylate when the initial metal ion concentration in Example 2 is 10 mg / L.

[0020] Figure 6 , Figure 7These are the adsorption amounts and removal rates obtained at different addition amounts of rosin-based tricarboxylate when the initial metal ion concentration is 20 mg / L in Example 3.

[0021] Figure 8 These are the results of three parallel enrichment and recovery experiments on metal cadmium ion solution.

[0022] Fig. 9 This is a comparison of the infrared spectra of the regenerated rosin-based tricarboxylate and the first-prepared rosin-based tricarboxylate. DETAILED DESCRIPTION

[0023] The content of the present invention is further explained in conjunction with the following preparation and application examples. Figures 1 to 9 .

[0024] Preparation implementation example

[0025] Preparation of rosin-based tricarboxylate

[0026] In a three-necked round-bottom flask, add 24 g of fumaric acid (fumaric acid) and 80 g of rosin, heat to 210° C. under nitrogen protection for 3 h, and cool to obtain fumaric rosin.

[0027] Then, 50 g of the above-mentioned fumaric rosin was dissolved in 400 mL of anhydrous ethanol, heated to 60° C. and stirred to completely dissolve the fumaric rosin (condensation reflux).

[0028] After complete dissolution, weigh 15g of potassium hydroxide and heat it to dissolve in 150mL of anhydrous ethanol, then add them to the fumarate rosin ethanol solution and reflux for 0.5h.

[0029] After the reaction, the solution was cooled to room temperature, and then vacuum filtered and dried to obtain a crude product of rosin tricarboxylate, which was dissolved in a 50% ethanol aqueous solution, and then placed in a water bath at 80°C for 0.5 h, and then allowed to stand for 8 hours for recrystallization, and vacuum filtered and dried to obtain a high-purity rosin tricarboxylate (recrystallization was performed twice).

[0030] After detection and analysis, the infrared spectrum of the rosin-based tricarboxylate obtained in this example is as follows Figure 1 shown.

[0031] Application Example 1

[0032] Example of removing metal ions at a concentration of 5 mg / L in water

[0033] (1) Prepare metal ion standard solution and draw the corresponding metal ion concentration standard curve

[0034] Weigh 0.2025 g of nickel chloride hexahydrate into a 250 mL volumetric flask and add deionized water to make a 200 mg / L nickel ion solution.

[0035] Weigh 0.0799 g of lead nitrate into a 250 mL volumetric flask and add deionized water to make a 200 mg / L lead ion solution.

[0036] Weigh 0.1341 g of copper chloride into a 250 mL volumetric flask and add deionized water to make a 200 mg / L copper ion solution.

[0037] Weigh 0.1374 g of manganese sulfate into a 250 mL volumetric flask and add deionized water to make a 200 mg / L manganese ion solution.

[0038] Weigh 0.1372 g of cadmium nitrate tetrahydrate into a 250 mL volumetric flask and add deionized water to prepare a 200 mg / L cadmium ion solution.

[0039] Take 5mL of the above 200mg / L solution in a 200mL volumetric flask to make a 5mg / L solution, adjust the pH to 6, then take 0.2mL, 0.4mL, 0.6mL, 0.8mL, and 1mL in a colorimetric tube and dilute to 10mL with deionized water, shake well, and measure by atomic absorption. The obtained standard curve equations are:

[0040] Y=0.12633+11.37141XY=0.00081+58.32432XY=0.1901+5.35089X

[0041] Y=0.20701+3.41879XY=-0.06665+3.96941X

[0042] Where: Y: ion concentration; X: absorbance. The concentration of ions in the solution is obtained from the standard curve.

[0043] (2) Removal of metal ions at a concentration of 5 mg / L

[0044] Add 0.1g / L to 0.8g / L of rosin-based tricarboxylate metal ion precipitant and 25mL of 5mg / L metal ion solution to a batch of 50mL conical bottles. Then put the batch of conical bottles into a shaker, shake at a set temperature for 24 hours, take out and filter through a microfiltration membrane, and use an atomic absorption spectrometer to determine the residual concentration of metal ions in the aqueous solution. According to the standard curve equation, the concentration of metal ions in the solution is obtained by the formula:

[0045]

[0046] Calculate the adsorption amount qe of rosin tricarboxylate on metal ions.

[0047] Wherein: qe is the adsorption amount of metal ions by rosin-based tricarboxylate (mg / g); C0 is the initial concentration of ions before adsorption (mg / L); Ce is the equilibrium concentration of ions after adsorption (mg / L); V is the volume of adsorption solution (L); m is the dosage of rosin-based tricarboxylate (g).

[0048] The concentration of metal ions in the solution was obtained according to the standard curve equation:

[0049]

[0050] Calculate the removal rate R of rosin-based tricarboxylate for metal ions.

[0051] Wherein: R is the removal rate of metal ions by rosin-based tricarboxylate (%); C0 is the initial concentration of ions before adsorption (mg / L); Ce is the equilibrium concentration of ions after adsorption (mg / L).

[0052] One batch of experiments was performed for each metal ion.

[0053] The experiment showed that the maximum adsorption capacity of nickel ions by rosin-based tricarboxylate was 25.42 mg / g and the maximum removal rate was 99.975%;

[0054] The experiment showed that the maximum adsorption capacity of lead ions by rosin-based tricarboxylate was 28.99 mg / g and the maximum removal rate was 99.984%.

[0055] The experiment showed that the maximum adsorption capacity of copper ions by rosin-based tricarboxylate was 29.06 mg / g and the maximum removal rate was 99.943%;

[0056] The experiment showed that the maximum adsorption capacity of manganese ions by rosin-based tricarboxylate was 29.63 mg / g and the maximum removal rate was 99.970%.

[0057] The experiment showed that the maximum adsorption capacity of cadmium ions by rosin-based tricarboxylate was 30.36 mg / g and the maximum removal rate was 99.983%.

[0058] For detailed results, see Figure 2 Figure 3 .

[0059] Application Example 2

[0060] Example of removing metal ions at a concentration of 10 mg / L in water

[0061] (1) Prepare metal ion standard solution and draw the corresponding metal ion concentration standard curve

[0062] Weigh 0.2025 g of nickel chloride hexahydrate into a 250 mL volumetric flask and add deionized water to make a 200 mg / L nickel ion solution.

[0063] Weigh 0.0799 g of lead nitrate into a 250 mL volumetric flask and add deionized water to make a 200 mg / L lead ion solution.

[0064] Weigh 0.1341 g of copper chloride into a 250 mL volumetric flask and add deionized water to make a 200 mg / L copper ion solution.

[0065] Weigh 0.1374 g of manganese sulfate into a 250 mL volumetric flask and add deionized water to make a 200 mg / L manganese ion solution.

[0066] Weigh 0.1372 g of cadmium nitrate tetrahydrate into a 250 mL volumetric flask and add deionized water to prepare a 200 mg / L cadmium ion solution.

[0067] Take 10mL of the above 200mg / L solution in a 200mL volumetric flask to make a 10mg / L solution, adjust the pH to 6, then take 0.1mL, 0.2mL, 0.3mL, 0.4mL, and 0.5mL in a colorimetric tube and dilute to 10mL with deionized water, shake well, and measure by atomic absorption. The obtained standard curve equations are:

[0068] Y=0.12633+11.37141XY=0.00081+58.32432XY=0.1901+5.35089X

[0069] Y=0.20701+3.41879XY=-0.06665+3.96941X

[0070] Where: Y: ion concentration; X: absorbance. The concentration of ions in the solution is obtained from the standard curve.

[0071] (2) Removal of metal ions at a concentration of 10 mg / L

[0072] Add 0.1g / L to 0.8g / L of rosin-based tricarboxylate precipitant to a 50mL conical flask, and add 25mL of a 10mg / L metal ion solution. Put it in a shaker, take it out after 24 hours, pass it through the membrane, and measure it by atomic absorption. According to the standard curve equation, the concentration of metal ions in the solution is obtained, and the adsorption amount qe and removal rate R of rosin-based tricarboxylate on metal ions are obtained by the same formula as in Application Example 1.

[0073] The experiment showed that the maximum adsorption capacity of nickel ions by rosin-based tricarboxylate was 46.44 mg / g and the maximum removal rate was 99.987%.

[0074] The experiment showed that the maximum adsorption capacity of lead ions by rosin tricarboxylate was 56.14 mg / g and the maximum removal rate was 99.992%.

[0075] The experiment showed that the maximum adsorption capacity of copper ions by rosin-based tricarboxylate was 54.27 mg / g and the maximum removal rate was 99.971%.

[0076] The experiment showed that the maximum adsorption capacity of manganese ions by rosin tricarboxylate was 56.55 mg / g and the maximum removal rate was 99.970%.

[0077] The experiment showed that the maximum adsorption capacity of cadmium ions by rosin-based tricarboxylate was 56.17 mg / g and the maximum removal rate was 99.992%.

[0078] For detailed results, see Figure 4 Figure 5 .

[0079] Application Example 3

[0080] Example of removing metal ions at a concentration of 20 mg / L in water

[0081] (1) Prepare metal ion standard solution and draw the corresponding metal ion concentration standard curve

[0082] Weigh 0.2025 g of nickel chloride hexahydrate into a 250 mL volumetric flask and add deionized water to make a 200 mg / L nickel ion solution.

[0083] Weigh 0.0799 g of lead nitrate into a 250 mL volumetric flask and add deionized water to make a 200 mg / L lead ion solution.

[0084] Weigh 0.1341 g of copper chloride into a 250 mL volumetric flask and add deionized water to make a 200 mg / L copper ion solution.

[0085] Weigh 0.1374 g of manganese sulfate into a 250 mL volumetric flask and add deionized water to make a 200 mg / L manganese ion solution.

[0086] Weigh 0.1372 g of cadmium nitrate tetrahydrate into a 250 mL volumetric flask and add deionized water to prepare a 200 mg / L cadmium ion solution.

[0087] Take 20mL of the above 200mg / L solution in a 200mL volumetric flask to make a 20mg / L solution, adjust the pH to 6, take 50mL of the 20mg / L solution in a 100mL volumetric flask and use deionized water to make a 10mg / L solution, then take 0.1mL, 0.2mL, 0.3mL, 0.4mL, and 0.5mL respectively and dilute to 10mL with deionized water, shake well, and measure by atomic absorption. The obtained standard curve equations are:

[0088] Y=0.12633+11.37141XY=0.00081+58.32432XY=0.1901+5.35089X

[0089] Y=0.20701+3.41879XY=-0.06665+3.96941X

[0090] Where: Y: ion concentration; X: absorbance. The concentration of ions in the solution is obtained from the standard curve.

[0091] (2) Removal of metal ions at a concentration of 20 mg / L

[0092] Add 0.1g / L to 0.8g / L of rosin-based tricarboxylate precipitant to a 50mL conical flask, and add 25mL of a 20mg / L metal ion solution. Put it in a shaker, take it out after 24 hours, pass it through the membrane, and measure it by atomic absorption. According to the standard curve equation, the concentration of metal ions in the solution is obtained, and the adsorption amount qe and removal rate R of rosin-based tricarboxylate on metal ions are obtained by the same formula as in Application Example 1.

[0093] The experiment showed that the maximum adsorption capacity of nickel ions by rosin-based tricarboxylate was 89.05 mg / g and the maximum removal rate was 99.994%.

[0094] The experiment showed that the maximum adsorption capacity of lead ions by rosin-based tricarboxylate was 104.42 mg / g and the maximum removal rate was 99.996%.

[0095] The experiment showed that the maximum adsorption capacity of copper ions by rosin-based tricarboxylate was 99.26 mg / g and the maximum removal rate was 99.896%.

[0096] The experiment showed that the maximum adsorption capacity of manganese ions by rosin tricarboxylate was 102.10 mg / g and the maximum removal rate was 99.990%.

[0097] The experiment showed that the maximum adsorption capacity of cadmium ions by rosin-based tricarboxylate was 94.02 mg / g and the maximum removal rate was 99.996%.

[0098] For detailed results, see Figure 6 Figure 7 .

[0099] Application Example 4

[0100] Example of recovery of metal ions in water

[0101] The precipitates generated by the adsorption of cadmium ions in Application Example 1, Application Example 2, and Application Example 3 were simply filtered and dried, and then 1 g was weighed and placed in a 25 mL conical flask, and 5 mL of a 10% H3PO4 solution was added for soaking. The metal ions in the rosin-based tricarboxylic acid heavy metal ion compound precipitate were exchanged and desorbed, and the rosin-based tricarboxylic acid formed by acidification was insoluble in water and could be filtered and separated, thus completing the enrichment and recovery operation. The recovery rates of metal ion enrichment in three parallel desorption experiments all reached more than 99.9%. For specific results, see Figure 8 .

[0102] Application Example 5

[0103] Regeneration of rosin-based tricarboxylate

[0104] The rosin-based tricarboxylic acid heavy metal ion compound precipitates obtained in Application Example 1, Application Example 2, and Application Example 3 were added to a 10% H3PO4 solution for full immersion treatment. The metal ions were exchanged into the solution and re-formed into water-insoluble rosin-based tricarboxylic acid. After filtering, washing, and drying, the rosin-based tricarboxylic acid was added to an ethanol solution of potassium hydroxide. A rosin-based tricarboxylate salt precipitate appeared, completing the regeneration operation of the product. The regenerated product and the initially prepared product were characterized by infrared spectroscopy. The spectra of the two were highly consistent, indicating that the regenerated product is exactly the same as the initially prepared product. For specific results, see Fig. 9 .

[0105] The technical means disclosed in the solution of the present invention are not limited to the technical means disclosed in the above technical means, but also include technical solutions composed of equivalent replacement of the above technical features. Matters not covered in the present invention belong to the common knowledge of those skilled in the art.

Claims

1. A water-soluble rosin-based tricarboxylate used for precipitation, removal and enrichment and recovery of heavy metal ions, wherein natural rosin and fumaric acid (fumaric acid) are subjected to DA addition at high temperature to obtain fumaric rosin, and then the fumaric rosin is heated and dissolved in ethanol, and then an appropriate amount of potassium hydroxide ethanol solution is added dropwise to obtain rosin-based tricarboxylate. The rosin-based tricarboxylate is added to a solution containing heavy metal ions such as copper, cadmium, and lead, and fully mixed at room temperature, so that the rosin-based tricarboxylate and the heavy metal ions form a solid compound precipitation, and after simple solid-liquid separation, the heavy metal ions in the water are adsorbed, removed or enriched and recovered, and the rosin-based tricarboxylate can be regenerated and reused.

2. The water-soluble rosin-based tricarboxylate according to claim 1 is used for precipitation removal of heavy metal ions, characterized in that: The steps include: Step a: fully mixing a rosin-based tricarboxylate precipitant with 5 mg / L to 20 mg / L of metal ions; Step b: As the reaction in step a proceeds, rosin-based tricarboxylate and heavy metal ions undergo ion exchange to form a solid compound precipitate; Step c: The solid compound precipitate appearing in the solution of step b is simply filtered to remove the heavy metal ions in the water.

3. The water-soluble rosin-based tricarboxylate according to claim 1 is used for the enrichment and recovery of heavy metal ions, characterized in that: The steps include: Step a: adding a rosin-based tricarboxylate precipitant to various water samples containing heavy metal ions and mixing them thoroughly, so that the rosin-based tricarboxylate and the heavy metal ions form a solid compound precipitate; Step b: filtering the solid compound precipitate obtained in step a, and briefly soaking the collected precipitate in an acid solution, so that the carboxyl oxygen of the rosin-based tricarboxylic acid in the solid compound is protonated and loses the ability to coordinate with heavy metal ions, and the rosin-based tricarboxylic acid form that is insoluble in water is restored, and at the same time, the heavy metal ions are exchanged into the solution; Step c: filtering out the water-insoluble rosin-based tricarboxylic acid in step b, and concentrating the solution if necessary to complete the enrichment and recovery of heavy metal ions.

4. The water-soluble rosin-based tricarboxylate according to claim 1, which can be regenerated and reused after being combined with heavy metal ions, is characterized in that The water-insoluble rosin-based tricarboxylic acid filtered out in step c of claim 3 is added to an ethanol solution of potassium hydroxide to re-form a rosin-based tricarboxylic acid potassium salt precipitate, which can be reused after simple filtration, washing and drying.

5. The water-soluble rosin-based tricarboxylate according to claim 1 is used for precipitation removal and enrichment recovery of heavy metal ions, characterized in that Rosin-based tricarboxylates have multiple adsorption sites.

6. The water-soluble rosin-based tricarboxylate according to claim 2 is used for precipitation removal and enrichment recovery of heavy metal ions, characterized in that: Used for adsorption, recovery or removal of various heavy metal ions in water.

7. A water-soluble rosin-based tricarboxylate according to claim 2 is used for precipitation and enrichment recovery of heavy metal ions, characterized in that: The heavy metal ions are metal ions greater than the third period in the periodic table, such as manganese ions, nickel ions, copper ions, cadmium ions, lead ions, and the like.

Images