阅读说明：本技术 聚乙二醇功能化的Fe3O4纳米粒子选择性分离富集Au(III)的方法 (Polyethylene glycol functionalized Fe3O4Method for selectively separating and enriching Au (III) from nanoparticles ) 是由 何裕建 杨旭 杨昆昊 于 2019-11-04 设计创作，主要内容包括：本发明为聚乙二醇功能化的Fe_3O_4纳米粒子选择性分离富集Au(III)的方法。将聚乙二醇对Fe_3O_4磁性纳米粒子进行功能化,通过两步反应合成了新型吸附剂(Fe_3O_4@CPTES@PEG)。该材料在pH=1.0的水溶液中对Au(III)具有特异性吸附,最大吸附量约为83 mg/g。吸附Au(III)后的材料可由硫酸亚铁选择性再生,至少可重复利用三次及以上。提供一个外部磁场即可让吸附Au(III)后的材料在水溶液中定向聚集从而达到分离的目的。除此之外,该材料也可用于金原矿、日用品及电子器件中金的富集、提取及检测,故在分离富集金领域具有巨大的应用潜力。(The invention is polyethylene glycol functionalized Fe 3 O 4 A method for selectively separating and enriching Au (III) from nanoparticles. Polyethylene glycol is added to Fe 3 O 4 Magnetic nano particles are functionalized, and a novel adsorbent (Fe) is synthesized through a two-step reaction 3 O 4 @ CPTES @ PEG). The material has specific adsorption on Au (III) in an aqueous solution with pH =1.0, and the maximum adsorption quantity is about 83 mg/g. The material after absorbing Au (III) can be selectively regenerated by ferrous sulfate and can be recycled at least three times and more. An external magnetic field is provided, so that the material adsorbed with Au (III) can be directionally aggregated in the aqueous solution, and the purpose of separation is achieved. In addition to thisThe material can also be used for enriching, extracting and detecting gold in gold raw ores, daily necessities and electronic devices, so that the material has great application potential in the field of gold separation and enrichment.)

1. Polyethylene glycol functionalized Fe₃O₄The method for selectively separating and enriching Au (III) by nanoparticles is characterized in that: the polyethylene glycol capable of specifically recognizing and adsorbing Au (III) in a strong acid (pH = 1.0) environment is successfully modified to Fe through a two-step reaction (see the steps in the specification and the attached figure 1)₃O₄Synthesis of Fe on magnetic nanoparticles₃O₄@ CPTES @ PEG composites, the synthesis steps for such adsorbents include, but are not limited to, the two-step reaction illustrated in the figures.

2. The polyethylene glycol-functionalized Fe of claim 1₃O₄The method for selectively separating and enriching Au (III) by nanoparticles is characterized in that: polyethylene glycol can specifically adsorb Au (III) in a strong acid (pH = 1.0) environment, and mainly utilizes H in an aqueous solution with pH =1.0⁺And H₂O to form H₃ ⁺After O, the O is combined with an oxygen atom in an ether bond in polyethylene glycol through a hydrogen bond to form an ionic associate { H ] with positive charge⁺·a(H₂O.b (PEG) } (a and b are coefficients), the association with negatively charged AuCl₄ ^-Combine to form a novel ionic associate { H⁺·a(H₂O)·b(PEG)···AuCl₄ ^-The principle of specific adsorption of (a and b are coefficients)Substances of au (iii) include, but are not limited to, polyethylene glycol.

3. The polyethylene glycol-functionalized Fe of claim 1₃O₄The method for selectively separating and enriching Au (III) by nanoparticles is characterized in that: using Fe₃O₄The magnetic nano particles have the excellent properties of easy dispersion, high modifiability, easy separation and the like, are used as magnetic material cores, and the polyethylene glycol is ingeniously modified on the surface, so that the easiness of separating the adsorbed materials from a water phase is obviously improved, and the substances capable of being used as the magnetic material cores include but are not limited to magnetic ferroferric oxide (Fe)₃O₄）。

4. The polyethylene glycol-functionalized Fe of claim 1₃O₄The method for selectively separating and enriching Au (III) by nanoparticles is characterized in that: the material is not only suitable for HAuCl with pH =1.0₄The gold in the aqueous solution has excellent selective adsorption effect, and can also be used for enriching, extracting and detecting gold in gold raw ore, daily necessities and electronic devices, and substances which contain gold and can be adsorbed by the material include but are not limited to HAuCl₄Gold ores, daily necessities and electronic devices.

5. The polyethylene glycol-functionalized Fe of claim 1₃O₄The method for selectively separating and enriching Au (III) by nanoparticles is characterized in that: the material has high reusability, the material adsorbed with Au (III) can be selectively regenerated by ferrous sulfate, and can be reused at least three times or more after simple post-treatment, and the substances capable of selectively regenerating the adsorbed magnetic material include but are not limited to ferrous sulfate.

Technical Field

The invention relates to polyethylene glycol functionalized Fe₃O₄The method for selectively separating and enriching Au (III) from nanoparticles specifically refers to modification of polyethylene glycol to Fe through simple two-step reaction₃O₄On the surface of magnetic nanoparticles, for HAuCl in acidity (pH = 1.0)₄Au (III) is specifically adsorbed in the aqueous solution. The method belongs to the field of resource recycling.

Background

Gold, as a noble metal, plays an important role in various fields such as medicine, electronics, modern communications and the like. Furthermore, gold is of widespread interest to the public due to its unique physicochemical properties. Unfortunately, however, the natural reserves of gold ores have begun to decline dramatically. Therefore, the recovery of gold from secondary resources has a very important significance on the effective utilization of the resources.

In the past, research and development on gold recovery methods have been focused, and among them, adsorption methods are considered to be the most promising method for recovering gold ions from aqueous solutions because of their advantages of simplicity, low cost, simple operation, high efficiency, insensitivity to toxic substances, and the like. Adsorbents such as carbon nanotubes, chelating resins, activated carbon, chitosan, aminopropyl silica gel and cellulose have appeared. Unfortunately, the adsorption capacity, reusability, adsorption rate and selectivity of these adsorbents have been poor. Moreover, the selection of a suitable adsorbent is the key to achieving efficient adsorption of gold ions in the resource environment.

Magnetic nanoparticles have recently received much attention due to their small size, large surface area, and good dispersibility in solvents. Some researchers reported that magnetic nanoparticles were used as adsorbents for the purification of copper ions, diazonium ions, and polluted water, respectively. However, studies on the separation and enrichment of gold ions from aqueous solutions have been rarely reported. J. The Kim research team selectively and efficiently recovers gold ions from wastewater by using tannic acid as an adsorbent and using a photochemical method. Unfortunately, however, the adsorbent cannot be easily and rapidly separated from the aqueous solution because it is not well combined with the magnetic nanoparticles, which greatly reduces the application field of the adsorbent. Although some chitosan and graphite carbon nano composite materials are constructed on the basis of taking a magnetic nanoparticle structure as an inner core for separating and concentrating gold ions in an aqueous solution, the adsorption capacity, reusability and chemoselectivity of the adsorbents are poor, so that the practical application of the adsorbents in many fields is limited. Therefore, Fe was developed₃O₄The nano particles are used as the inner core and have the advantages of large adsorption capacity, high repeated utilization rate, high adsorption rate and chemical selectionThere is a great demand for new adsorbents with high performance and excellent performance.

Disclosure of Invention

The invention aims to provide a material for specifically adsorbing Au (III) in an aqueous solution, and the material can be used for specifically adsorbing Au (III) in the aqueous solution, thereby providing a reliable solution and thinking for various problems which plague the field of gold ion recovery at present.

In order to achieve the purpose, the invention provides polyethylene glycol functionalized Fe₃O₄A method for selectively separating and enriching Au (III) by nanoparticles. The method is characterized in that:

1. polyethylene glycol functionalized Fe₃O₄The method for selectively separating and enriching Au (III) by nanoparticles is characterized in that: the polyethylene glycol capable of specifically recognizing and adsorbing Au (III) in a strong acid (pH = 1.0) environment is successfully modified to Fe through a two-step reaction (see the steps in the specification and the attached figure 1)₃O₄Synthesis of Fe on magnetic nanoparticles₃O₄@ CPTES @ PEG composites, the synthesis steps for such adsorbents include, but are not limited to, the two-step reaction illustrated in the figures.

2. The polyethylene glycol-functionalized Fe of claim 1₃O₄The method for selectively separating and enriching Au (III) by nanoparticles is characterized in that: polyethylene glycol can specifically adsorb Au (III) in a strong acid (pH = 1.0) environment, and mainly utilizes H + and H2O to form H in an aqueous solution with pH =1.0₃ ⁺After O, the O is combined with an oxygen atom in an ether bond in polyethylene glycol through a hydrogen bond to form an ionic associate { H ] with positive charge₊•a(H₂B (peg) } (a and b are coefficients), the association with negatively charged AuCl₄ ^-Combine to form a novel ionic associate { H⁺•a(H₂O)•b(PEG)•••AuCl₄ ^-The specific adsorption principle of (a and b are coefficients), and the substances for specifically adsorbing Au (III) include but are not limited to polyethylene glycol.

3. The polyethylene glycol of claim 1Functionalized Fe₃O₄The method for selectively separating and enriching Au (III) by nanoparticles is characterized in that: using Fe₃O₄The magnetic nano particles have the excellent properties of easy dispersion, high modifiability, easy separation and the like, are used as magnetic material cores, and the polyethylene glycol is ingeniously modified on the surface, so that the easiness of separating the adsorbed materials from a water phase is obviously improved, and the substances capable of being used as the magnetic material cores include but are not limited to magnetic ferroferric oxide (Fe)₃O₄）。

4. The polyethylene glycol-functionalized Fe of claim 1₃O₄The method for selectively separating and enriching Au (III) by nanoparticles is characterized in that: the material is not only suitable for HAuCl with pH =1.0₄The gold in the aqueous solution has excellent selective adsorption effect, and can also be used for enriching, extracting and detecting gold in gold raw ore, daily necessities and electronic devices, and substances which contain gold and can be adsorbed by the material include but are not limited to HAuCl₄Gold ores, daily necessities and electronic devices.

5. The polyethylene glycol-functionalized Fe of claim 1₃O₄The method for selectively separating and enriching Au (III) by nanoparticles is characterized in that: the material has high reusability, the material adsorbed with Au (III) can be selectively regenerated by ferrous sulfate, and can be reused at least three times or more after simple post-treatment, and the substances capable of selectively regenerating the adsorbed magnetic material include but are not limited to ferrous sulfate.

The invention has the beneficial effects that:

1) the synthesis steps are simple, the conditions are mild, and the raw materials are easy to obtain.

2) Large adsorption capacity, high repeated utilization rate, easy magnetic separation and high chemical selectivity.

3) Provides a reliable solution and thinking for various problems which plague the gold ion recovery at present.

Drawings

The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

FIG. 1 is Fe₃O₄A synthesis method of @ CPTES @ PEG magnetic nanoparticles.

FIG. 2 is the contact time vs. Fe₃O₄@ CPTES @ PEG magnetic nanoparticles the effect of adsorbing Au (III).

FIG. 3 is Fe₃O₄The reusability of @ CPTES @ PEG magnetic nanoparticles to Au (III) adsorption.

FIG. 4 is a real sample of gold ore powder from Douglas laevis, inner Mongolia.

Fig. 5 shows a gold ion solution prepared by digesting a real sample of gold ore powder of douglas left-hand inner mongolian araffia with aqua regia and diluting the volume with a dilute hydrochloric acid solution with pH = 1.0.

Detailed Description