阅读说明：本技术 铜铁层状双金属氢氧化物、铜铁层状双金属氢氧化物/碳基复合材料及其制备方法和应用 (Copper and iron layered double hydroxide, copper and iron layered double hydroxide/C-base composte material and its preparation method and application ) 是由 赵国萍 刘阳桥 孙盛睿 王杨杨 李娜 于 2019-09-03 设计创作，主要内容包括：本发明涉及铜铁层状双金属氢氧化物、铜铁层状双金属氢氧化物/碳基复合材料及其制备方法和应用,所述铜铁层状双金属氢氧化物的制备方法包括：(1)将金属铜盐和金属铁盐溶于去离子水中,得到混合溶液；(2)在混合溶液中加入碱性试剂,调节pH=5～7后,在60～130℃下陈化20～80小时,得到所述铜铁层状双金属氢氧化物。(The present invention relates to copper and iron layered double hydroxides, copper and iron layered double hydroxide/C-base composte material and its preparation method and application, the preparation method of the copper and iron layered double hydroxide includes: that copper salt and etal molysite are dissolved in deionized water by (1), obtains mixed solution；(2) alkaline reagent is added in mixed solution, after adjusting pH=5~7, is aged 20~80 hours at 60~130 DEG C, obtains the copper and iron layered double hydroxide.)

1. a kind of preparation method of copper and iron layered double hydroxide characterized by comprising

(1) copper salt and etal molysite are dissolved in deionized water, obtain mixed solution；

(2) alkaline reagent is added in mixed solution, after adjusting pH=5~7, is aged 20~80 hours, obtains at 60~130 DEG C To the copper and iron layered double hydroxide.

2. a kind of preparation method of copper and iron layered double hydroxide/C-base composte material characterized by comprising

(1) copper salt, etal molysite and carbon material are dissolved in deionized water, obtain mixed solution, the carbon material is oxygen At least one of graphite alkene, graphene, carbon nanotube, active carbon and Nano diamond；

(2) alkaline reagent is added in mixed solution, after adjusting pH=5~7, is aged 20~80 hours, obtains at 60~130 DEG C To the copper and iron layered double hydroxide/C-base composte material.

3. preparation method according to claim 1 or 2, which is characterized in that the copper salt is selected from copper nitrate, chlorination At least one of copper, copper sulphate, copper acetate；The etal molysite be selected from ferric nitrate, ferrous nitrate, iron chloride, frerrous chloride, At least one of ferric sulfate, ferrous sulfate, ferric acetate, ferrous acetate.

4. preparation method according to claim 1 or 2, which is characterized in that mole of the copper salt and etal molysite Than for 1:(0.2~0.5).

5. preparation method according to claim 2, which is characterized in that the mass ratio of the carbon material and copper salt is 1: (20~200).

6. preparation method according to any one of claims 1-5, which is characterized in that the alkaline reagent is sodium hydroxide At least one of solution, potassium hydroxide solution, sodium carbonate liquor and solution of potassium carbonate.

7. a kind of copper and iron layered double hydroxide of preparation method preparation according to claim 1, which is characterized in that Cu/Fe molar ratio is 1:(0.2~0.5 in the copper and iron layered double hydroxide).

8. a kind of copper and iron layered double hydroxide/carbon-based composite wood of preparation method preparation according to claim 2 Material, which is characterized in that copper and iron layered double hydroxide in the copper and iron layered double hydroxide/C-base composte material Mass ratio with carbon material is 1:(0.01~0.5)；Cu/Fe molar ratio is 1 in the copper and iron layered double hydroxide: (0.2~0.5).

9. a kind of method of photochemical catalysis removal ammonia nitrogen, which is characterized in that by copper and iron layered double hydroxide and copper and iron At least one of layered double hydroxide/C-base composte material is added together as catalyst and hypochlorite to ammonia nitrogen In pollutant solution, and pH=6.5~8.5 are adjusted, under simulated solar irradiation irradiation, removes ammonia nitrogen pollutant to degrade.

10. according to the method described in claim 9, it is characterized in that, the concentration of the ammonia nitrogen pollutant solution be 20~ 500mg/L；The dosage of the catalyst is every liter of ammonia nitrogen pollutant solution of 0.5~5 g/；The hypochlorite and ammonia and nitrogen pollution The concentration ratio of object is (6~10): 1.

Technical field

The present invention relates to copper and iron layered double hydroxides, copper and iron layered double hydroxide/C-base composte material And its preparation method and application, and in particular to a kind of copper and iron layered double hydroxide and its C-base composte material, preparation Method and photochemical catalysis remove the application of water body ammonia nitrogen, belong to water-treatment technology field.

Background technique

Ammonia nitrogen is pollutant common in water, is mainly derived from the row such as chemical fertilizer, process hides, cultivation, petrochemical industry, meat packing Waste water and the landfill leachate discharge of industry and municipal sewage and agricultural irrigation drain.The discharge of a large amount of ammonia nitrogen waste waters can cause Water eutrophication, generation stench, supplying water encounters difficulties.Currently, mainly having object for the processing method of ammonia nitrogen waste water both at home and abroad Change denitrogenation (break chlorine method, chemical precipitation method, ion-exchange etc.), biological denitrificaion method and advanced oxidation processes (ozone oxidation Method, photochemical catalytic oxidation and electrochemical oxidation process), but the above method exists that different degrees of process cycle is long, equipment requirement is high, Treatment effect is limited to be also easy to produce secondary pollution problems, it is difficult to be used widely.

Layered double hydroxide (LDHs) is emerging one kind by nominal price layers of metal hydroxides and interlayer anion The compound with ordered structure constituted, including hydrotalcite and houghite compound are a kind of important inorganic functional materials Material.The material is layer structure, and laminate band structure positive charge, interlayer is made of anion and hydrone, passes through between layers Electrostatic interaction is combined together.Its general structure are as follows: [M^I _1-X M^II _X(OH)₂]^x+(A^n-)_x/n·mH₂O (wherein M^I=Mg²⁺、Ni²⁺、 Fe²⁺、Co²⁺、Mn²⁺Deng M^Ⅱ=Al³⁺、Fe³⁺、Ti⁴⁺Deng A^n-For interlayer anion, m is intermediary water molecular number).Such one kind Structure obviously has the advantage for forming adjustable, laminate element dispersibility height and large specific surface area.For theoretically, any divalent Trivalent metal ion can be freely composed LDH, however find in actual research, bivalent cupric ion and trivalent metal ion Such as Fe³⁺It is very difficult to form LDH structure.This is because bivalent cupric ion has strong Jiang Taile effect in octahedral structure (Jahn-Teller effect).When being co-precipitated with trivalent metal ion, be preferentially produced the octahedra complex salt of deformation and The hydrotalcite structure of layer structure cannot be formed.The preparation condition of copper-based LDH material is very harsh, product prepared by conventional method General purity is not high, contains copper oxide impurity more.But copper ion is high, cheap, resourceful as a kind of catalytic stability Active constituent, it is very potential in the photocatalytic degradation application aspect of waste water.In addition, hypochlorite is usually used in water removal Ammonia nitrogen pollutant, but the living radical type dullness and limited amount that individually chemical method generates, imitate the removal of ammonia nitrogen Rate is lower.

Summary of the invention

In view of the above-mentioned problems, the object of the present invention is to provide copper and iron layered double hydroxide, copper and iron stratiform are double Metal hydroxides/C-base composte material and its preparation method and application.

In a first aspect, the present invention provides a kind of preparation methods of copper and iron layered double hydroxide, comprising:

(1) copper salt and etal molysite are dissolved in deionized water, obtain mixed solution；

(2) alkaline reagent is added in mixed solution, after adjusting pH=5~7, is aged 20~80 hours, obtains at 60~130 DEG C To the copper and iron layered double hydroxide.

Present invention firstly discovers that there are sensitive relations, pH mistakes between coprecipitation process and reacting liquid pH value for copper and ferro element Small, copper can not precipitate, and pH is excessive, then will form excessive copper oxide impurity.Further pass through pH control accurate means (pH =5~7) preparation for realizing high-purity copper and iron LDH can form copper and iron under copper ion Jiang Taile effect under the conditions of this pH The co-precipitation of hydroxide, and effectively copper oxide is inhibited to occur, form high-purity material.

Preferably, the copper salt is selected from least one of copper nitrate, copper chloride, copper sulphate, copper acetate；The gold Belong to molysite in ferric nitrate, ferrous nitrate, iron chloride, frerrous chloride, ferric sulfate, ferrous sulfate, ferric acetate, ferrous acetate It is at least one.

Preferably, the molar ratio of the copper salt and etal molysite is 1:(0.2~0.5).

Preferably, the alkaline reagent is sodium hydroxide solution, potassium hydroxide solution, sodium carbonate liquor and solution of potassium carbonate At least one of.

Second aspect, the present invention also provides a kind of preparations of copper and iron layered double hydroxide/C-base composte material Method, comprising:

(1) copper salt, etal molysite and carbon material are dissolved in deionized water, obtain mixed solution, the carbon material is oxygen At least one of graphite alkene, graphene, carbon nanotube, active carbon and Nano diamond；

(2) alkaline reagent is added in mixed solution, after adjusting pH=5~7, is aged 20~80 hours, obtains at 60~130 DEG C To the copper and iron layered double hydroxide.

Present invention firstly discovers that there are sensitive relations between coprecipitation process and reacting liquid pH value for copper, pH is too small, Copper can not precipitate, and pH is excessive, then will form excessive copper oxide impurity.Further pass through pH control accurate means (pH=5 ~7) preparation for realizing high-purity copper and iron LDH can form copper and iron hydrogen-oxygen under the conditions of this pH under copper ion Jiang Taile effect The co-precipitation of compound, and effectively copper oxide is inhibited to occur, form high-purity material.Since carbon material has, from a wealth of sources, price is low The advantages that honest and clean, morphosis enriches, large specific surface area and physicochemical properties are stable, with many distinctive physics, chemically Matter is with a wide range of applications in absorption, catalysis, medicine and other fields.It is mutually compound with LDH material by the way that carbon material is added, it can It is obviously improved the catalytic capability of material.

Preferably, the copper salt is selected from least one of copper nitrate, copper chloride, copper sulphate, copper acetate；The gold Belong to molysite in ferric nitrate, ferrous nitrate, iron chloride, frerrous chloride, ferric sulfate, ferrous sulfate, ferric acetate, ferrous acetate It is at least one.

Preferably, the molar ratio of the copper salt and etal molysite is 1:(0.2~0.5).

Preferably, the alkaline reagent is sodium hydroxide solution, potassium hydroxide solution, sodium carbonate liquor and solution of potassium carbonate At least one of.

Preferably, the mass ratio of the carbon material and copper salt is 1:(20~200).

The third aspect, the present invention also provides a kind of copper and iron layered bi-metal hydrogen-oxygens prepared according to above-mentioned preparation method Compound, Cu/Fe molar ratio is 1:(0.2~0.5 in the copper and iron layered double hydroxide).

Fourth aspect, the present invention also provides a kind of copper and iron layered bi-metal hydrogen-oxygens prepared according to above-mentioned preparation method Compound/C-base composte material, copper and iron layered bi-metal hydrogen-oxygen in the copper and iron layered double hydroxide/C-base composte material The mass ratio of compound and carbon material is 1:(0.01~0.5)；Cu/Fe molar ratio is in the copper and iron layered double hydroxide 1:(0.2~0.5).

5th aspect, the present invention also provides a kind of methods of photochemical catalysis removal ammonia nitrogen, by copper and iron layered bi-metal At least one of hydroxide and copper and iron layered double hydroxide/C-base composte material are used as catalyst and hypochlorite It is added together into ammonia nitrogen pollutant solution, and adjusts pH=6.5~8.5, under simulated solar irradiation irradiation, remove ammonia to degrade Nitrogen pollutant.

In the present invention, the iron-based oxidation-reduction pair of the catalyst surface is mutually complexed with copper-based oxidation-reduction pair and has Extremely strong electron-transport and transfer ability, while illumination condition can accelerate its redox cycle process, be conducive to active sites The constant regeneration of point can generate various active free radical, both enrich living radical under sodium hypochlorite synergistic effect Type, and number of free radical is improved, for when the degradation of ammonia nitrogen, ammonia nitrogen removal frank to be obviously improved in water body.

Preferably, the concentration of the ammonia nitrogen pollutant solution is 20~500mg/L；The dosage of the catalyst be 0.5~ Every liter of ammonia nitrogen pollutant solution of 5g/；The concentration of the hypochlorite and ammonia nitrogen pollutant ratio is (6~10): 1.

Preferably, the hypochlorite is sodium hypochlorite or/and postassium hypochlorite.

Beneficial effects of the present invention are as follows:

(1) copper and iron layered double hydroxide and its C-base composte material have excellent electronic transmission performance in the present invention, Light induced electron and the combined efficiency in hole pair can substantially reduce under illumination condition；

(2) preparation method that the present invention uses, preparation process is easy to operate, can carry out at room temperature, advantage of lower cost；Gained material Expect good crystallinity with high purity；Each ingredient is uniformly dispersed in composite material and interfacial bonding property is good；

(3) gained copper and iron layered double hydroxide and its C-base composte material are in the photocatalysis developed-sodium hypochlorite association With having high utilization rate and catalytic activity in catalysis technique, to the ammonia nitrogen removal significant effect in water body；

(4) gained copper and iron layered double hydroxide and its C-base composte material have large specific surface area, active site rich Feature rich, electronic transmission performance is excellent, can provide high-speed electrical transmission for copper and iron layered double hydroxide catalytic process Channel.

Detailed description of the invention

Fig. 1 is the XRD diagram of Cu-Fe LDH material prepared by 1-2 of the embodiment of the present invention and comparative example 3-4, can from figure Know compared to the obtained sample of other methods, sample purity prepared by method provided by the invention is high, and impurity is few, crystallinity It is good；

Fig. 2 is that the SEM of Cu-Fe prepared by the present invention (4:1) LDH material schemes, and typical layer structure is formed as we know from the figure, table Face is smooth, free from admixture.

Fig. 3 is the SEM figure of Cu-Fe (4:1) LDH material prepared by the embodiment of the present invention 3, as we know from the figure prepared sample purity Height, impurity is few, good crystallinity.

Specific embodiment

The present invention is further illustrated below by way of following embodiments, it should be appreciated that following embodiments are merely to illustrate this Invention, is not intended to limit the present invention.

In the disclosure, copper and iron layered double hydroxide is prepared by improving coprecipitation.Above method system Standby step is simple, and reaction condition is mild, low in cost, the purity is high and good crystallinity of product.

Illustrate to following exemplary the method for present invention preparation copper and iron layered double hydroxide.

Copper salt and etal molysite are dissolved according to a certain percentage after being completely dissolved in deionized water, addition lye (or Claim alkaline reagent), until reaction solution to certain ph 5~7, is subsequently placed in baking oven and is aged certain time under certain temperature, so After take out.Using centrifugation, washing, drying, grinding etc., copper and iron layered double hydroxide is obtained.It is preferred that being adjusted to spy After determining pH, continue stirring 1~2 hour, keeps its mixing more uniform.

In alternative embodiments, copper salt include one of copper nitrate, copper chloride, copper sulphate, copper acetate or It is several.Etal molysite includes ferric nitrate, ferrous nitrate, iron chloride, frerrous chloride, ferric sulfate, ferrous sulfate, ferric acetate, acetic acid One or more of ferrous iron.Wherein, the molar ratio of copper salt and etal molysite can be 1:(0.2~0.5).

In alternative embodiments, lye used can for sodium hydroxide solution, potassium hydroxide solution, sodium carbonate liquor, One or more of solution of potassium carbonate.The temperature of above-mentioned ageing can be 60~130 DEG C.The time of ageing can be small for 20~80 When.

In the disclosure, copper and iron layered double hydroxide/carbon-based composite wood is prepared by improving coprecipitation Material.The mass ratio of copper and iron layered double hydroxide and carbon-based material can be 1:(0.01~0.5 in composite material).This is compound Material is mainly prepared by copper and iron layered double hydroxide and carbon-based material (carbon material).Wherein, the double gold of copper and iron stratiform Belong to hydroxide to be uniformly distributed with carbon-based material, interfacial contact is good, is conducive to the quick transmission of electronics in catalytic process.It is above-mentioned Method preparation step is simple, and reaction condition is mild, low in cost, the purity is high and good crystallinity of product.Say to following exemplary Bright present invention preparation copper and iron layered double hydroxide/C-base composte material method.

Copper salt and etal molysite ultrasound in processed solvent is dissolved according to a certain percentage to be added to after being completely dissolved Lye, until reaction solution to certain ph 5~7, is subsequently placed in baking oven and is aged certain time under certain temperature, then take out. Again through centrifugation, washing, drying, grinding etc., copper and iron layered double hydroxide/C-base composte material is obtained.It is above-mentioned Processing solvent includes deionized water-graphene suspension, deionized water-carbon nano tube suspension, deionized water-active carbon suspension Liquid, deionized water-nanodiamond suspension.It is preferred that continuing stirring 1~2 hour after being adjusted to specific pH, make its mixing more Add uniformly.

In alternative embodiments, copper salt include one of copper nitrate, copper chloride, copper sulphate, copper acetate or It is several.Etal molysite includes ferric nitrate, ferrous nitrate, iron chloride, frerrous chloride, ferric sulfate, ferrous sulfate, ferric acetate, acetic acid One or more of ferrous iron.Wherein, the molar ratio of copper salt and etal molysite can be 1:(0.2~0.5).

In alternative embodiments, carbon material used include: graphene oxide, graphene, active carbon, carbon nanotube, Nano diamond material is one or more of.Wherein, the mass ratio of carbon material and copper salt can be 1:(20~200).

In alternative embodiments, lye used can for sodium hydroxide solution, potassium hydroxide solution, sodium carbonate liquor, One or more of solution of potassium carbonate.The temperature of above-mentioned ageing can be 60~130 DEG C.The time of ageing can be small for 20~80 When.

In embodiments of the present invention, under ultraviolet light and/or radiation of visible light, copper and iron layered double hydroxide, Copper and iron layered double hydroxide/C-base composte material cooperates with hypochlorite to generate various active free radical as catalyst, It can be used for ammonia nitrogen in photochemical catalysis removal (oxidation) water body, realize the fast degradation of water body middle and high concentration ammonia nitrogen.Specifically, Copper and iron layered double hydroxide and its C-base composte material prepared by the present invention are in ultraviolet and/or visible light illumination condition Under have regeneration advantage be continuously circulated to the quick electronics transfer of sodium hypochlorite and active site, can promote generate various active from The efficient degradation of ammonia nitrogen in water body is realized at nitrogen by base, and then by ammonium oxidation.

In the present invention, under ultraviolet light or/and radiation of visible light, with copper and iron layered double hydroxide or/and copper Iron layered double hydroxide/C-base composte material is as catalyst, under certain pH conditions (for example, pH is 6.5~8.5) It cooperates with hypochlorite (for example, sodium hypochlorite, postassium hypochlorite etc.) to generate various active free-radical oxidation ammonia nitrogen, realizes high in water body The fast degradation of concentration ammonia nitrogen, the catalyst have under illumination effect to the quick electronics transfer of sodium hypochlorite and active sites Point persistent loop regeneration advantage, and the free radical type in catalytic process can be enriched, promote to generate hydroxyl radical free radical, super oxygen freedom The one or more free radical such as base, chlorine radical, chlorine oxygen radical, chlorine radical ion, single line oxygen.

In the embodiment of science choosing, the concentration of ammonia nitrogen solution (or ammonia nitrogen pollutant solution) used can for 20~ 500mg/L.The dosage of the catalyst can be every liter of ammonia nitrogen solution of 0.5~5g/.The hypochlorite of addition is molten in ammonia nitrogen pollutant The ratio of the concentration of concentration and ammonia nitrogen pollutant ammonia nitrogen in solution pollutant in liquid can be (6~10): 1.

Enumerate embodiment further below with the present invention will be described in detail.It will similarly be understood that following embodiment is served only for this Invention is further described, and should not be understood as limiting the scope of the invention, those skilled in the art is according to this hair Some nonessential modifications and adaptations that bright above content is made all belong to the scope of protection of the present invention.Following examples are specific Technological parameter etc. is also only an example in OK range, i.e. those skilled in the art can be done properly by the explanation of this paper In the range of select, and do not really want to be defined in hereafter exemplary specific value.