CN103667717B

CN103667717B - A kind of at CO3The method simultaneously reclaiming neodymium, praseodymium, dysprosium, cobalt, ferrum under-OH system from neodymium iron boron greasy filth

Info

Publication number: CN103667717B
Application number: CN201310692815.6A
Authority: CN
Inventors: 刘敏; 赖伟鸿; 李春燕; 尹小文; 金琼花; 岳明; 索红莉
Original assignee: Beijing University of Technology
Current assignee: Ganzhou Xihong Permanent Magnet Technology Co ltd
Priority date: 2013-12-17
Filing date: 2013-12-17
Publication date: 2016-06-29
Anticipated expiration: 2033-12-17
Also published as: CN103667717A

Abstract

A kind of at CO₃The method simultaneously reclaiming neodymium, praseodymium, dysprosium, cobalt, ferrum under-OH system from neodymium iron boron greasy filth, belongs to neodymium iron boron greasy filth recovery technology field.CO₃-OH system thermodynamic study and simulation, set up thermodynamical model, it is determined that technique applicatory and technological parameter.And at CO₃Regulate pH=6～7 under-OH system and carry out " coordinating-precipitation ", can reach to reclaim the effect of neodymium, praseodymium, dysprosium, cobalt, ferrum simultaneously.This flow process can effectively shorten early stage Process Exploration, simple to operate, concise in technology, effectively reduces waste discharge, and realizes the full recovery of neodymium in neodymium iron boron greasy filth, praseodymium, dysprosium, cobalt, ferrum.Wherein, response rate >=98% of neodymium；Response rate >=99% of praseodymium；Response rate >=89% of cobalt；Response rate >=99% of dysprosium；Response rate >=99% of ferrum.

Description

A kind of at CO3The method simultaneously reclaiming neodymium, praseodymium, dysprosium, cobalt, ferrum under-OH system from neodymium iron boron greasy filth

Technical field

The present invention relates to a kind of at CO₃The method extracting neodymium, praseodymium, dysprosium, cobalt, ferrum under-OH system from neodymium iron boron greasy filth, belongs to neodymium iron boron greasy filth recovery technology field.

Background technology

Nineteen eighty-three with American scientist, Japan has almost found that its huge magnetic energy product has refreshed existing permanent magnet material record, causes the change that permanent magnet material market, the world is huge with since (third generation) RE permanent magnetic alloy that neodymium iron boron is matrix simultaneously.The exploitation of domestic neodymium iron boron is very fast, and the yearly productive capacity of the nearly various schools of thinkers enterprise in the whole nation reaches nearly more than 100,000 ton.It is well known that in the production process of NdFeB material, have many leftover pieces, defect ware and cut the waste material got off, total losses are up to more than 30%, therefore, strengthen research and production that neodymium iron boron waste material reclaims, have important realistic meaning.

Along with from neodymium iron boron waste material, the technology of recovering rare earth is increasingly mature, increasing businessman sees abundant profit therein.According to data, being with in Zhejiang and Guangdong one, the big and small producer reclaiming neodymium iron boron waste material just has several thousand.And this wherein just has black workshop, the underground much not having qualification of production, they will obtain the greasy filth after the neodymium iron boron waste material of coming, particularly polishing and line cutting, be only carry out coarse oxidizing roasting, then through the flow process such as acid-soluble, thus extracting central rare earth element.Owing to these businessmans had not both had production permit, also without regular production flow process.In this way not only significant wastage to rare earth resources, but also local environment can be formed huge pollution.

For the object of study neodymium iron boron greasy filth of this patent, the NdFeB magnetic powder how again preparing regeneration from neodymium iron boron greasy filth is the research core of this problem.Have bibliographical information, have people just to utilize Fe-Pr and Fe-Nd rapid quenching technique successfully to prepare magnetic is long-pending can the Hard Magnetic phase of up to 40KOe.Domestic Xiao Yao good fortune and Zhou Shouzeng et al. once used reduction-diffusion process successfully to produce out neodymium iron boron.The method by by NdO powder, Fe powder, Ca powder mixing compressing after, at 860 DEG C-1180 DEG C, carry out vat blue RS, be shaped again afterwards, sinter, it is thus achieved that magnetic energy product (BH) max=200-238KJ/m³NdFeB alloy.Sun Guangfei, Chen Jufang have also prepared NdFeB alloy by using reduction fusion method.Reduction fusion method is to reduce Neodymium chloride by calcium metal, and the neodymium metal being then reduced under the high temperature conditions merges with alloy element Fe, boron and prepares NdFeB alloy.And AngshumanPal, AlexanderGabay, GeorgeC.Hadjipanayis et al. is once by preparing NdFeB alloy and rich neodymium phase by Dineodymium trioxide powder, ferroboron, calcium powder ball milling, heat-treating methods, and wherein the coercivity of NdFeB alloy is more than 12KOe.Also someone passes through successfully to have prepared that NdFeB is nanocrystalline and nanometer sheet by adding surfactant in high-energy ball milling.Therefore, preparing NdFeB alloy by this method of Mechano-chemical Synthesizing is be worth using for reference.

The applicant intend adopting solid liquid phase-solid phase in NdFeB greasy filth-physical method for separation greasy filth acid-soluble-neodymium ferrum co-precipitation-high-temperature calcination-mechanochemical reaction synthesis NdFeB magnetic powder technique, with the acid-soluble sedimentation method, the sulfuric acid double salt sedimentation method, full extraction these compared by the method for Separation-purification, either directly through solid liquid phase-solid phase in NdFeB greasy filth-physical method for separation greasy filth acid-soluble-neodymium ferrum co-precipitation-high-temperature calcination-mechanochemical reaction synthesis NdFeB magnetic powder technique prepares the method for NdFeB alloy and can reduce cost further, reduce numerous and diverse chemical process, human resources and material resources are saved, decrease the discharge of waste water and waste liquid simultaneously, and realize reclaiming and recycling economy truly of full element.

Possessing the element of recyclable reproduction value in neodymium iron boron greasy filth containing neodymium, praseodymium, dysprosium, cobalt, ferrum these five kinds, will prepare neodymium iron boron regeneration magnetic powder, high-recovery is settled out neodymium simultaneously, praseodymium, dysprosium, cobalt, ferrum become crucial.

Summary of the invention

In the present invention, would first, through neodymium, praseodymium, dysprosium, cobalt, these five kinds of elements of ferrum by calculating simulation, set up thermodynamical model, determined and optimize the optimal parameter of neodymium, praseodymium, dysprosium, cobalt, optimised process that ferrum reclaims simultaneously and technique by thermodynamical model.

It is contemplated that at CO₃The thermodynamical model of neodymium, praseodymium, dysprosium, cobalt, five kinds of elements of ferrum is set up under-OH system, the result using for reference simulation determines that cooperation-depositing technology that neodymium, praseodymium, dysprosium, cobalt, ferrum reclaim selects, the process program being determined by reclaims the compound of neodymium, praseodymium, dysprosium, cobalt, these five kinds of elements of ferrum simultaneously, reclaims product and can be used for regenerating the preparation of neodymium iron boron.

Present invention determine that at CO₃The method extracting neodymium, praseodymium, dysprosium, cobalt, iron process under-OH system from neodymium iron boron greasy filth, it is characterised in that be the technical scheme is that first, by searching each element at CO₃Contingent complex reaction and reaction equilibrium constant under-OH system, set up thermodynamical model (preferably by MATLAB software for calculation)；Then, the thermodynamical model by having been built up is determined and is reclaimed the selection of parameter in neodymium, praseodymium, dysprosium, cobalt, the technique of ferrum and technique: at CO₃Under-OH system, it is determined that technique is: neodymium iron boron greasy filth distillation, acid-soluble, oxidation, coordinate precipitation obtain product；

The foundation of above-mentioned thermodynamical model (i.e. thermodynamical model after sedimentation equilibrium) comprises the following steps: first, consult at CO₃Under-OH system, the equilibrium constant of neodymium, praseodymium, dysprosium, cobalt, the contingent reaction of ferrum and each reaction, is based upon CO by chemical equilibrium, mass balance, charge conservation₃Thermodynamical model under-OH system, can be obtained equation by the ionization equilibrium of water:

[H⁺]=10^-pH(1-1)

[OH^-]=Kw*10^pH(1-2)

At CO₃In-OH system, the free metal ion concentration in solution is:

[Nd³⁺]=min{(Kspnc/[CO₃ ^2-]³)^1/2,Kspnh/[OH^-]³}(1-3)[Pr³⁺]==min{(Ksppc/[CO₃ ^2-]³)^1/2,KsppH/[OH^-]³}(1-4)

[Dy³⁺]=min{(Kspdc/[CO₃ ^2-]³)^1/2,Kspdh/[OH^-]³}(1-5)

[Fe³⁺]=Kspf3h/[OH^-]³(1-6)

[Fe²⁺]=min{Kspf2c/[CO₃ ^2-],Kspf3h/[OH^-]²}(1-7)

[Co²⁺]=min{Kspcc/[CO₃ ^2-],Kspch/[OH^-]²}(1-8)

[C]=[CO₃ ^2-]+[HCO₃ ^-]+[H₂CO₃](1-9)

[C]=[CO₃ ^2-]{1+10^-pH/K_ac2+10^-2pH/(K_ac2*K_ac1)}(1-10)

Owing to each metal ion is with OH^-There is complex reaction, therefore obtain the total concentration of each metal ion in solution according to mass conservation law:

[Nd]=[Nd³⁺]+[Nd(OH)²⁺]

=[Nd³⁺]+K_nh*[Nd³⁺]*[OH^-](1-11)

[Pr]=[Pr³⁺]+[Pr(OH)²⁺]

=[Pr³⁺]+K_pH*[Pr³⁺]*[OH^-](1-12)

[Dy]=[Dy³⁺]+[Dy(OH)²⁺]

=[Dy³⁺]+K_dh*[Dy³⁺]*[OH^-](1-13)

[Fe2]=[Fe²⁺]+[Fe(OH)⁺]+[Fe(OH)₂ ⁰]+[Fe(OH)₃ ^-]+[Fe(OH)₄ ^2-]

=[Fe²⁺]{1+K_f2h1*[OH^-]+K_f2h2*[OH^-]²+K_f2h3*[OH^-]³+K_f2h4*[OH^-]⁴}(1-14)

[Fe3]=[Fe³⁺]+[Fe(OH)²⁺]+[Fe(OH)₂ ⁺]+[Fe(OH)₃ ⁰]+[Fe(OH)₄ ^2-]

=[Fe³⁺]{1+K_f3h1*[OH^-]+K_f3h2*[OH^-]²+K_f3h3*[OH^-]³}(1-15)

[Co]=[Co²⁺]+[Co(OH)⁺]+[Co(OH)₂ ⁰]+[Co(OH)₃ ^-]+[Co(OH)₄ ^2-]+2*[Co₂(OH)₃ ^3-]+4*[Co₄(OH)₄ ^4-]

=[Co²⁺]{1+K_ch1*[OH^-]+K_ch2*[OH^-]²+K_ch3*[OH^-]³+K_ch4*[OH^-]⁴+2*K_ch21*[Co²⁺]*[OH^-]+4*K_ch44*[Co²⁺]³*[OH^-]⁴}(1-16)

Table 1 parameter is brought in (1-1)-(1-16) equation, and Simultaneous Equations (1-1)-(1-16), pH in conversion system, the value of [Nd], [Pr], [Dy], [Fe2], [Fe3], [Co] in system can be obtained after the precipitation under different condition, be based upon CO by chemical equilibrium, mass balance, charge conservation₃Thermodynamical model under-OH system, above-mentioned [Fe2] is divalent concentration of iron, and [Fe3] is 3 valency concentration of iron.

Preferred: to utilize MATLAB program calculation model:

x=0:0.5:14;

k=0.1;

p=k./[1+10.^(10.329-x)+10.^(16.781-2*x)];

a=min(sqrt(1.08*10^(-33)./p.^3),10.^(20.5-3*x));

b=min(10^(-10.50)./p,10.^(11.69-2*x));

c=10.^(3.45-3*x);

w=min(10^(-12.84)./p,10.^(13.77-2*x));

e=min(sqrt(1.08*10^(-32)./p.^3),10.^(21.17-3*x));

i=min(sqrt(1.08*10^(-31)./p.^3),10.^(21.85-3*x));

j=a.*(1+10.^(x-8.5));

g=b.*[1+10.^(x-8.44)+10.^(2*x-18.23)+10.^(3*x-32.33)+10.^(4*x-47.72)];

h=c.*[1+10.^(x-2.13)+10.^(2*x-6.83)+10.^(3*x-12.33)];

q=w.*(1+10.^(x-10.7)+10.^(2.*x-18.8)+10.^(3.*x-31.5)+10.^(4.*x-45.8)+2.*10.^(x-11.3).*w+4.*10.^(4.*x-30.4).^(w.^3));

r=e.*(1+10.^(x-9.7));

l=i.*(1+10.^(x-8.8));

y=log10(j);

m=log10(g);

n=log10(h);

o=log10(q)

t=log10(r)

z=log10(l)

plot(x,y,x,m,x,n,x,o,x,t,x,z)

Wherein, x represents pH value；K represents the concentration of total carbonic acid [C]；P represents CO in solution₃ ^2-Concentration；A, b, c, w, e, i represent the free metal ion concentration value of [Nd], [Fe2], [Fe3], [Co], [Dy], [Pr] respectively；J, g, h, q, r, l represent remaining total concentration in [Nd], [Fe2], [Fe3], [Co], [Dy], [Pr] solution respectively；What y, m, n, o, t, z then represented respectively is remaining total concentration denary logarithm value in [Nd], [Fe2], [Fe3], [Co], [Dy], [Pr] solution.

At CO₃The method extracting neodymium, praseodymium, dysprosium, cobalt, ferrum under-OH system from neodymium iron boron greasy filth, it is characterised in that comprise the following steps: after neodymium iron boron greasy filth is carried out distillation pretreatment, take hydrochloric acid respectively and pretreated neodymium iron boron greasy filth is dissolved and filters, add H₂O₂, stir fully oxidized after, add NaOH and regulate pH=3-7, and add NaHCO₃Solution, filters the precipitation obtained, washs three times, dries, namely obtain the product of the neodymium iron boron that can be used for preparation regeneration, it is preferable that add NaOH adjustment pH=6-7.

The H of hydrochloric acid 75ml, 3ml30%.wt of preferred above-mentioned every 5g neodymium iron boron greasy filth correspondence 4mol/L₂O₂, 1mol/L the NaHCO of NaOH, 1mol/L₃Solution 16ml.

As shown in Figure 1.According to Fig. 1, it is believed that should select 3 valency iron ions as far as possible, best precipitation neodymium, praseodymium, dysprosium, cobalt, ferrum pH scope in 3～7, and should can pass through that a step process obtains neodymium, praseodymium, dysprosium, cobalt, ferrum coordinate precipitated product.

At CO₃Under-OH system, reclaim the ranging for of pH value of neodymium, praseodymium, dysprosium, cobalt, ferrum: when 6～7, response rate >=98% of neodymium；Response rate >=99% of praseodymium；Response rate >=89% of cobalt；Response rate >=99% of dysprosium；Response rate >=99% of ferrum.

The beneficial effects of the present invention is:

(1) the early stage complexity exploration simultaneously reclaiming neodymium, praseodymium, dysprosium, cobalt, five kinds of elements of ferrum is overcome, it is provided that the analogy method of a kind of simplicity.

(2) make valuable element in neodymium iron boron greasy filth be obtained for good recovery, decrease the waste of element；Being reclaimed by one-time process, make recovery multiple element need repeatedly the present situation of technique to get a new look, simple to operate, method is feasible.

Accompanying drawing explanation

Fig. 1 CO₃The impact that in-OH system, neodymium, ferrum, cobalt, praseodymium, dysprosium concentration are changed by pH value；

Fig. 2 CO₃Neodymium in-OH system, ferrum, cobalt, praseodymium, dysprosium the response rate with the change of pH value.

Detailed description of the invention

Below in conjunction with example, the present invention being further described, single present invention is not limited to following

Embodiment.

Embodiment 1

Table 1 " CO₃-OH " main chemical reactions that relates in system and equilibrium constant

NO.	Reactions	logK	NO.	Reactions	logK
						1	H₂O=H⁺+OH^—	logK_w=-14	16	Nd+OH^—=Nd(OH)²⁺	logK_nh=5.5
2	Co²⁺+OH^—=Co(OH)⁺	logK_ch1=3.3	17	Pr+OH^—=Pr(OH)²⁺	logK_pH=4.3
						3	Co²⁺+2OH^—=Co(OH)₂ ⁰	logK_ch2=9.2	18	Dy+OH^—=Dy(OH)²⁺	logK_dh=5.2
4	Co²⁺+3OH^—=Co(OH)₃ ^—	logK_ch3=10.5	19	Co(OH)₂(s)=Co²⁺+2OH^—	logKspch=-14.23
						5	Co²⁺+4OH^—=Co(OH)₄ ^2-	logK_ch4=10.2	20	Fe(OH)₂(s)=Fe²⁺+2OH^—	logKspf2h=-16.31
6	2Co²⁺+OH^—=Co₂(OH)³⁺	logK_ch21=2.7	21	Fe(OH)₃(s)=Fe³⁺+3OH^—	logKspf3h=-38.55
						7	4Co²⁺+4OH^—=Co₄(OH)₄ ⁴⁺	logK_ch44=25.6	22	Nd(OH)₃(s)=Nd³⁺+3OH^—	logKspnh=-21.49
8	Fe²⁺+OH^—=Fe(OH)⁺	logK_f2h1=5.56	23	Pr(OH)₃(s)=Pr³⁺+3OH^—	logKsppH=-21.17
						9	Fe²⁺+2OH^—=Fe(OH)₂ ⁰	logK_f2h2=9.77	24	Dy(OH)₃(s)=D_y ³⁺+3OH^—	logKspdh=-21.85
10	Fe²⁺+3OH^—=Fe(OH)₃ ^—	logK_f2h3=9.67	25	H₂CO₃=H⁺+HCO₃ ^—	logK_ac1=-6.352
						11	Fe²⁺+4OH^-=Fe(OH)₄ ^2-	logK_f2h4=18.58	26	HCO₃ ^—=H⁺+CO₃ ^2—	logK_ac2=-10.329
12	Fe³⁺+OH^—=Fe(OH)²⁺	logK_f3h1=11.87	27	CoCO₃(s)=Co²⁺+CO₃ ^2—	logKspcc=-12.84
						13	Fe³⁺+2OH^—=Fe(OH)₂ ⁺	logK_f3h2=21.17	28	FeCO₃(s)=Fe²⁺+CO₃ ^2—	logKspf2c=-12.84

14	Fe³⁺+3OH^—=Fe(OH)₂ ⁰	logK_f3h3=29.67	29	NdCO₃(s)=Nd²⁺+CO₃ ^2—	logKspnc=-32.97
						15	PrCO₃(s)=Pr²⁺+CO₃ ^2—	logKsppc=-27.7	30	DyCO₃(s)=Dy²⁺+CO₃ ^2—	logKspdc=-28.1

In theory part: first, consult at CO₃The equilibrium constant of neodymium, praseodymium, dysprosium, cobalt, the contingent reaction of ferrum and each reaction under-OH system, as shown in table 1.It is based upon CO by chemical equilibrium, mass balance, charge conservation₃Thermodynamical model under-OH system, can be obtained equation by the ionization equilibrium of water:

[H⁺]=10^-pH(1-1)

[OH^-]=Kw*10^pH(1-2)

At CO₃In-OH system, the free metal ion concentration in solution is:

[Nd³⁺]=min{(Kspnc/[CO₃ ^2-]³)^1/2,Kspnh/[OH^-]³}(1-3)

[Pr³⁺]==min{(Ksppc/[CO₃ ^2-]³)^1/2,KsppH/[OH^-]³}(1-4)

[Dy³⁺]=min{(Kspdc/[CO₃ ^2-]³)^1/2,Kspdh/[OH^-]³}(1-5)

[Fe³⁺]=Kspf3h/[OH^-]³(1-6)

[Fe²⁺]=min{Kspf2c/[CO₃ ^2-],Kspf3h/[OH^-]²}(1-7)

[Co²⁺]=min{Kspcc/[CO₃ ^2-],Kspch/[OH^-]²}(1-8)

[C]=[CO₃ ^2-]+[HCO₃ ^-]+[H₂CO₃](1-9)

[C]=[CO₃ ^2-]{1+10^-pH/K_ac2+10^-2pH/(K_ac2*K_ac1)}(1-10)

[Nd]=[Nd³⁺]+[Nd(OH)²⁺]

=[Nd³⁺]+K_nh*[Nd³⁺]*[OH^-](1-11)

[Pr]=[Pr³⁺]+[Pr(OH)²⁺]

=[Pr³⁺]+K_pH*[Pr³⁺]*[OH^-](1-12)

[Dy]=[Dy³⁺]+[Dy(OH)²⁺]

=[Dy³⁺]+K_dh*[Dy³⁺]*[OH^-](1-13)

[Fe2]=[Fe²⁺]+[Fe(OH)⁺]+[Fe(OH)₂ ⁰]+[Fe(OH)₃ ^-]+[Fe(OH)₄ ^2-]

[Fe3]=[Fe³⁺]+[Fe(OH)²⁺]+[Fe(OH)₂ ⁺]+[Fe(OH)₃ ⁰]+[Fe(OH)₄ ^2-]

=[Fe³⁺]{1+K_f3h1*[OH^-]+K_f3h2*[OH^-]²+K_f3h3*[OH^-]³}(1-15)

Table 1 parameter is brought in (1-1)-(1-16) equation, and Simultaneous Equations (1-1)-(1-16),

Available MATLAB programming:

x=0:0.5:14;

k=0.1;

p=k./[1+10.^(10.329-x)+10.^(16.781-2*x)];

a=min(sqrt(1.08*10^(-33)./p.^3),10.^(20.5-3*x));

b=min(10^(-10.50)./p,10.^(11.69-2*x));

c=10.^(3.45-3*x);

w=min(10^(-12.84)./p,10.^(13.77-2*x));

e=min(sqrt(1.08*10^(-32)./p.^3),10.^(21.17-3*x));

i=min(sqrt(1.08*10^(-31)./p.^3),10.^(21.85-3*x));

j=a.*(1+10.^(x-8.5));

g=b.*[1+10.^(x-8.44)+10.^(2*x-18.23)+10.^(3*x-32.33)+10.^(4*x-47.72)];

h=c.*[1+10.^(x-2.13)+10.^(2*x-6.83)+10.^(3*x-12.33)];

r=e.*(1+10.^(x-9.7));

l=i.*(1+10.^(x-8.8));

y=log10(j);

m=log10(g);

n=log10(h);

o=log10(q)

t=log10(r)

z=log10(l)

plot(x,y,x,m,x,n,x,o,x,t,x,z)

Wherein, x represents pH value；K represents the concentration of total carbonic acid [C]；P represents CO in solution₃ ^2-Concentration；A, b, c, w, e, i represent the free metal ion concentration value of [Nd], [Fe2], [Fe3], [Co], [Dy], [Pr] respectively；J, g, h, q, r, l represent remaining total concentration in [Nd], [Fe2], [Fe3], [Co], [Dy], [Pr] solution respectively；What y, m, n, o, t, z then represented respectively is remaining total concentration denary logarithm value in [Nd], [Fe2], [Fe3], [Co], [Dy], [Pr] solution.PH in conversion system, can obtain after the precipitation under different condition the value of [Nd], [Pr], [Dy], [Fe2], [Fe3], [Co] in system, be based upon CO by chemical equilibrium, mass balance, charge conservation₃Thermodynamical model under-OH system, above-mentioned [Fe2] is divalent concentration of iron, and [Fe3] is 3 valency concentration of iron.

At experimental section: taking after the neodymium iron boron greasy filth of five parts of respectively 5g carries out distillation pretreatment, pretreated neodymium iron boron greasy filth is dissolved and filters by the hydrochloric acid 75ml taking 4mol/L respectively, and addition 3ml content is the H of 30%.wt₂O₂, stir fully oxidized after, the NaOH adding 1mol/L regulates pH=3, and adds the NaHCO of 1mol/L₃Solution 16ml, filters the precipitation obtained, washs three times, dries, namely obtain the product of the neodymium iron boron that can be used for preparation regeneration.Take supernatant and carry out ICP-OES test, it is thus achieved that result as shown in Figure 2: the response rate of neodymium is: 18%；The response rate of ferrum is: 98%；The response rate of cobalt is: 26%；The response rate of praseodymium is: 29%；The response rate of dysprosium is: 95%.

Embodiment 2

NO.	Reactions	logK	NO.	Reactions	logK
						1	H₂O=H⁺+OH^—	logK_w=-14	15	Nd+OH^—=Nd(OH)²⁺	logK_nh=5.5
2	Co²⁺+OH^—=Co(OH)⁺	logK_ch1=3.3	16	Pr+OH^—=Pr(OH)²⁺	logK_pH=4.3

3	Co²⁺+2OH^—=Co(OH)₂ ⁰	logK_ch2=9.2	17	Dy+OH^—=Dy(OH)²⁺	logK_dh=5.2
						4	Co²⁺+3OH^—=Co(OH)₃ ^—	logK_ch3=10.5	18	Co(OH)₂(s)=Co²⁺+2OH^—	logKspch=-14.23
5	Co²⁺+4OH^—=Co(OH)₄ ^2-	logK_ch4=10.2	19	Fe(OH)₂(s)=Fe²⁺+2OH^—	logKspf2h=-16.31
						6	2Co²⁺+OH^—=Co₂(OH)³⁺	logK_ch21=2.7	20	Fe(OH)₃(s)=Fe³⁺+3OH^—	logKspf3h=-38.55 6 -->
7	4Co²⁺+4OH^—=Co₄(OH)₄ ⁴⁺	logK_ch44=25.6	21	Nd(OH)₃(s)=Nd³⁺+3OH^—	logKspnh=-21.49
						8	Fe²⁺+OH^—=Fe(OH)⁺	logK_f2h1=5.56	22	Pr(OH)₃(s)=Pr³⁺+3OH^—	logKsppH=-21.17
9	Fe²⁺+2OH^—=Fe(OH)₂ ⁰	logK_f2h2=9.77	23	Dy(OH)₃(s)=Dy³⁺+3OH^—	logKspdh=-21.85
						10	Fe²⁺+3OH^—=Fe(OH)₃ ^—	logK_f2h3=9.67	24	H₂CO₃=H⁺+HCO₃ ^—	logK_ac1=-6.352
11	Fe²⁺+4OH^—=Fe(OH)₄ ^2-	logK_f2h4=18.58	25	HCO₃ ^—=H⁺+CO₃ ^2—	logK_ac2=-10.329
						12	Fe³⁺+OH^—=Fe(OH)²⁺	logK_f3h1=11.87	26	CoCO₃(s)=Co²⁺+CO₃ ^2—	logKspcc=-12.84
13	Fe³⁺+2OH^—=Fe(OH)₂ ⁺	logK_f3h2=21.17	27	FeCO₃(s)=Fe²⁺+CO₃ ^2—	logKspf2c=-12.84
						14	Fe³⁺+3OH^—=Fe(OH)₃ ⁰	logK_f3h3=29.67	28	NdCO₃(s)=Nd²⁺+CO₃ ^2—	logKspnc=-32.97

In theory part: first, consult at CO₃The equilibrium constant of neodymium, praseodymium, dysprosium, cobalt, the contingent reaction of ferrum and each reaction under-OH system, as shown in table 1.It is based upon CO by chemical equilibrium, mass balance, charge conservation₃Thermodynamical model under-OH system, as shown in Figure 1.According to Fig. 1, it is believed that should select 3 valency iron ions as far as possible, best precipitation neodymium, praseodymium, dysprosium, cobalt, ferrum pH scope in 3～7, and should can pass through that a step process obtains neodymium, praseodymium, dysprosium, cobalt, ferrum coordinate precipitated product.

At experimental section: taking after the neodymium iron boron greasy filth of five parts of respectively 5g carries out distillation pretreatment, pretreated neodymium iron boron greasy filth is dissolved and filters by the hydrochloric acid 75ml taking 4mol/L respectively, and addition 3ml content is the H of 30%.wt₂O₂, stir fully oxidized after, the NaOH adding 1mol/L regulates pH=4, and adds the NaHCO of 1mol/L₃Solution 16ml, filters the precipitation obtained, washs three times, dries, namely obtain the product of the neodymium iron boron that can be used for preparation regeneration.Take supernatant and carry out ICP-OES test, it is thus achieved that result as shown in Figure 2: the response rate of neodymium is: 34%；The response rate of ferrum is: 99%；The response rate of cobalt is: 20%；The response rate of praseodymium is: 43%；The response rate of dysprosium is: 96%.

Embodiment 3

NO.	Reactions	logK	NO.	Reactions	logK
						1	H₂O=H⁺+OH^—	logK_w=-14	16	Nd+OH^—=Nd(OH)²⁺	logK_nh=5.5
2	Co²⁺+OH^—=Co(OH)⁺	logK_ch1=3.3	17	Pr+OH^—=Pr(OH)²⁺	logK_pH=4.3
						3	Co²⁺+2OH^—=Co(OH)₂ ⁰	logK_ch2=9.2	18	Dy+OH^—=Dy(OH)²⁺	logK_dh=5.2
4	Co²⁺+3OH^—=Co(OH)₃ ^—	logK_ch3=10.5	19	Co(OH)₂(s)=Co²⁺+2OH^—	logKspch=-14.23
						5	Co²⁺+4OH^—=Co(OH)₄ ^2-	logK_ch4=10.2	20	Fe(OH)₂(s)=Fe²⁺+2OH^—	logKspf2h=-16.31
6	2Co²⁺+OH^—=Co₂(OH)³⁺	logK_ch21=2.7	21	Fe(OH)₃(s)=Fe³⁺+3OH^—	logKspf3h=-38.55
						7	4Co²⁺+4OH^—=Co₄(OH)₄ ⁴⁺	logK_ch44=25.6	22	Nd(OH)₃(s)=Nd³⁺+3OH^—	logKspnh=-21.49
8	Fe²⁺+OH^—=Fe(OH)⁺	logK_f2h1=5.56	23	Pr(OH)₃(s)=Pr³⁺+3OH^—	logKsppH=-21.17
						9	Fe²⁺+2OH^—=Fe(OH)₂ ⁰	logK_f2h2=9.77	24	Dy(OH)₃(s)=Dy³⁺+3OH^—	logKspdh=-21.85
10	Fe²⁺+3OH^—=Fe(OH)₃ ^—	logK_f2h3=9.67	25	H₂CO₃=H⁺+HCO₃ ^—	logK_ac1=-6.352
						11	Fe²⁺+4OH^—=Fe(OH)₄ ^2-	logK_f2h4=18.58	26	HCO₃ ^—=H⁺+CO₃ ^2—	logK_ac2=-10.329
12	Fe³⁺+OH^—=Fe(OH)²⁺	logK_f3h1=11.87	27	CoCO₃(s)=Co²⁺+CO₃ ^2—	logKspcc=-12.84
						13	Fe³⁺+2OH^—=Fe(OH)₂ ⁺	logK_f3h2=21.17	28	FeCO₃(s)=Fe²⁺+CO₃ ^2—	logKspf2c=-12.84
14	Fe³⁺+3OH^—=Fe(OH)₂ ⁰	logK_f3h3=29.67	29	NdCO₃(s)=Nd²⁺+CO₃ ^2—	logKspnc=-32.97
						15	PrCO₃(s)=Pr²⁺+CO₃ ^2—	logKsppc=-27.7	30	DyCO₃(s)=Dy²⁺+CO₃ ^2—	logKspdc=-28.1

At experimental section: taking after the neodymium iron boron greasy filth of five parts of respectively 5g carries out distillation pretreatment, pretreated neodymium iron boron greasy filth is dissolved and filters by the hydrochloric acid 75ml taking 4mol/L respectively, and addition 3ml content is the H of 30%.wt₂O₂, stir fully oxidized after, the NaOH adding 1mol/L regulates pH=5, and adds the NaHCO of 1mol/L₃Solution 16ml, filters the precipitation obtained, washs three times, dries, namely obtain the product of the neodymium iron boron that can be used for preparation regeneration.Take supernatant and carry out ICP-OES test, it is thus achieved that result as shown in Figure 2: the response rate of neodymium is: 85%；The response rate of ferrum is: 99%；The response rate of cobalt is: 26%；The response rate of praseodymium is: 92%；The response rate of dysprosium is: 98%.

Embodiment 4

NO.	Reactions	logK	NO.	Reactions	logK
						1	H₂O=H⁺+OH^—	logK_w=-14	16	Nd+OH^—=Nd(OH)²⁺	logK_nh=5.5
2	Co²⁺+OH^—=Co(OH)⁺	logK_ch1=3.3	17	Pr+OH^—=Pr(OH)²⁺	logK_pH=4.3
						3	Co²⁺+2OH^—=Co(OH)₂ ⁰	logK_ch2=9.2	18	Dy+OH^—=Dy(OH)²⁺	logK_dh=5.2
4	Co²⁺+3OH^—=Co(OH)₃ ^—	logK_ch3=10.5	19	Co(OH)₂(s)=Co²⁺+2OH^—	logKspch=-14.23
						5	Co²⁺+4OH^—=Co(OH)₄ ^2-	logK_ch4=10.2	20	Fe(OH)₂(s)=Fe²⁺+2OH^—	logKspf2h=-16.31
6	2Co²⁺+OH^—=Co₂(OH)³⁺	logK_ch21=2.7	21	Fe(OH)₃(s)=Fe³⁺+3OH^—	logKspf3h=-38.55
						7	4Co²⁺+4OH^—=Co₄(OH)₄ ⁴⁺	logK_ch44=25.6	22	Nd(OH)₃(s)=Nd³⁺+3OH^—	logKspnh=-21.49
8	Fe²⁺+OH^—=Fe(OH)⁺	logK_f2h1=5.56	23	Pr(OH)₃(s)=Pr³⁺+3OH^—	logKsppH=-21.17
						9	Fe²⁺+2OH^—=Fe(OH)₂ ⁰	logK_f2h2=9.77	24	Dy(OH)₃(s)=Dy³⁺+3OH^—	logKspdh=-21.85
10	Fe²⁺+3OH^—=Fe(OH)₃ ^—	logK_f2h3=9.67	25	H₂CO₃=H⁺+HCO₃ ^—	logK_ac1=-6.352
						11	Fe²⁺+4OH^—=Fe(OH)₄ ^2-	logK_f2h4=18.58	26	HCO₃ ^—=H⁺+CO₃ ^2—	logK_ac2=-10.329
12	Fe³⁺+OH^—=Fe(OH)²⁺	logK_f3h1=11.87	27	CoCO₃(s)=Co²⁺+CO₃ ^2—	logKspcc=-12.84
						13	Fe³⁺+2OH^—=Fe(OH)₂ ⁺	logK_f3h2=21.17	28	FeCO₃(s)=Fe²⁺+CO₃ ^2—	logKspf2c=-12.84

At experimental section: taking after the neodymium iron boron greasy filth of five parts of respectively 5g carries out distillation pretreatment, pretreated neodymium iron boron greasy filth is dissolved and filters by the hydrochloric acid 75ml taking 4mol/L respectively, and addition 3ml content is the H of 30%.wt₂O₂, stir fully oxidized after, the NaOH adding 1mol/L regulates pH=6, and adds the NaHCO of 1mol/L₃Solution 16ml, filters the precipitation obtained, washs three times, dries, namely obtain the product of the neodymium iron boron that can be used for preparation regeneration.Take supernatant and carry out ICP-OES test, it is thus achieved that result as shown in Figure 2: the response rate of neodymium is: 98%；The response rate of ferrum is: 99%；The response rate of cobalt is: 89%；The response rate of praseodymium is: 99%；The response rate of dysprosium is: 99%.

Embodiment 5

NO.	Reactions	logK	NO.	Reactions	logK
						1	H₂O=H⁺+OH^—	logK_w=-14	16	Nd+OH^—=Nd(OH)²⁺	logK_nh=5.5
2	Co²⁺+OH^—=Co(OH)⁺	logK_ch1=3.3	17	Pr+OH^—=Pr(OH)²⁺	logK_pH=4.3
						3	Co²⁺+2OH^—=Co(OH)₂ ⁰	logK_ch2=9.2	18	Dy+OH^—=Dy(OH)²⁺	logK_dh=5.2
4	Co²⁺+3OH^—=Co(OH)₃ ^—	logK_ch3=10.5	19	Co(OH)₂(s)=Co²⁺+2OH^—	logKspch=-14.23
						5	Co²⁺+4OH^—=Co(OH)₄ ^2-	logK_ch4=10.2	20	Fe(OH)₂(s)=Fe²⁺+2OH^—	logKspf2h=-16.31

6	2Co²⁺+OH^—=Co₂(OH)³⁺	logK_ch21=2.7	21	Fe(OH)₃(s)=Fe³⁺+3OH^—	logKspf3h=-38.55
						7	4Co²⁺+4OH^—=Co₄(OH)₄ ⁴⁺	logK_ch44=25.6	22	Nd(OH)₃(s)=Nd³⁺+3OH^—	logKspnh=-21.49 8 -->
8	Fe²⁺+OH^—=Fe(OH)⁺	logK_f2h1=5.56	23	Pr(OH)₃(s)=Pr³⁺+3OH^—	logKsppH=-21.17
						9	Fe²⁺+2OH^—=Fe(OH)₂ ⁰	logK_f2h2=9.77	24	Dy(OH)₃(s)=Dy³⁺+3OH^—	logKspdh=-21.85
10	Fe²⁺+3OH^—=Fe(OH)₃ ^—	logK_f2h3=9.67	25	H₂CO₃=H⁺+HCO₃ ^—	logK_ac1=-6.352
						11	Fe²⁺+4OH^—=Fe(OH)₄ ^2-	logK_f2h4=18.58	26	HCO₃ ^—=H⁺+CO₃ ^2—	logK_ac2=-10.329
12	Fe³⁺+OH^—=Fe(OH)²⁺	logK_f3h1=11.87	27	CoCO₃(s)=Co²⁺+CO₃ ^2—	logKspcc=-12.84
						13	Fe³⁺+2OH^—=Fe(OH)₂ ⁺	logK_f3h2=21.17	28	FeCO₃(s)=Fe²⁺+CO₃ ^2—	logKspf2c=-12.84
14	Fe³⁺+3OH^—=Fe(OH)₂ ⁰	logK_f3h3=29.67	29	NdCO₃(s)=Nd²⁺+CO₃ ^2—	logKspnc=-32.97
						15	PrCO₃(s)=Pr²⁺+CO₃ ^2—	logKsppc=-27.7	30	DyCO₃(s)=Dy²⁺+CO₃ ^2—	logKspdc=-28.1

At experimental section: taking after the neodymium iron boron greasy filth of five parts of respectively 5g carries out distillation pretreatment, pretreated neodymium iron boron greasy filth is dissolved and filters by the hydrochloric acid 75ml taking 4mol/L respectively, and addition 3ml content is the H of 30%.wt₂O₂, stir fully oxidized after, the NaOH adding 1mol/L regulates pH=7, and adds the NaHCO of 1mol/L₃Solution 16ml, filters the precipitation obtained, washs three times, dries, namely obtain the product of the neodymium iron boron that can be used for preparation regeneration.Take supernatant and carry out ICP-OES test, it is thus achieved that result as shown in Figure 2: the response rate of neodymium is: 98%；The response rate of ferrum is: 99%；The response rate of cobalt is: 99%；The response rate of praseodymium is: 99%；The response rate of dysprosium is: 99%.

In sum, considering cost and the response rate, reclaim neodymium, praseodymium, dysprosium, cobalt, ferrum optimal pH range for: 6～7.

Claims

1. at CO₃The method extracting neodymium, praseodymium, dysprosium, cobalt, ferrum under-OH system from neodymium iron boron greasy filth, it is characterised in that comprise the following steps: after neodymium iron boron greasy filth is carried out distillation pretreatment, take hydrochloric acid respectively and pretreated neodymium iron boron greasy filth is dissolved and filters, add H₂O₂, stir fully oxidized after, add NaOH and regulate pH=6-7, and add NaHCO₃Solution, filters the precipitation obtained, washs three times, dries, namely obtain and can be used for the neodymium of neodymium iron boron of preparation regeneration, praseodymium, dysprosium, cobalt, ferrum；

The H of hydrochloric acid 75ml, 3ml30%.wt of above-mentioned every 5g neodymium iron boron greasy filth correspondence 4mol/L₂O₂, 1mol/L the NaHCO of NaOH, 1mol/L₃Solution 16ml.